{"question": "A 21-year-old sexually active male complains of fever, pain during urination, and inflammation and pain in the right knee. A culture of the joint fluid shows a bacteria that does not ferment maltose and has no polysaccharide capsule. The physician orders antibiotic therapy for the patient. The mechanism of action of action of the medication given blocks cell wall synthesis, which of the following was given?", "answer": "Ceftriaxone", "options": {"A": "Chloramphenicol", "B": "Gentamicin", "C": "Ciprofloxacin", "D": "Ceftriaxone", "E": "Trimethoprim"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 5-year-old girl is brought to the emergency department by her mother because of multiple episodes of nausea and vomiting that last about 2 hours. During this period, she has had 6–8 episodes of bilious vomiting and abdominal pain. The vomiting was preceded by fatigue. The girl feels well between these episodes. She has missed several days of school and has been hospitalized 2 times during the past 6 months for dehydration due to similar episodes of vomiting and nausea. The patient has lived with her mother since her parents divorced 8 months ago. Her immunizations are up-to-date. She is at the 60th percentile for height and 30th percentile for weight. She appears emaciated. Her temperature is 36.8°C (98.8°F), pulse is 99/min, and blood pressure is 82/52 mm Hg. Examination shows dry mucous membranes. The lungs are clear to auscultation. Abdominal examination shows a soft abdomen with mild diffuse tenderness with no guarding or rebound. The remainder of the physical examination shows no abnormalities. Which of the following is the most likely diagnosis?", "answer": "Cyclic vomiting syndrome", "options": {"A": "Cyclic vomiting syndrome", "B": "Gastroenteritis", "C": "Hypertrophic pyloric stenosis", "D": "Gastroesophageal reflux disease", "E": "Acute intermittent porphyria"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 40-year-old woman presents with difficulty falling asleep, diminished appetite, and tiredness for the past 6 weeks. She says that, despite going to bed early at night, she is unable to fall asleep. She denies feeling anxious or having disturbing thoughts while in bed. Even when she manages to fall asleep, she wakes up early in the morning and is unable to fall back asleep. She says she has grown increasingly irritable and feels increasingly hopeless, and her concentration and interest at work have diminished. The patient denies thoughts of suicide or death. Because of her diminished appetite, she has lost 4 kg (8.8 lb) in the last few weeks and has started drinking a glass of wine every night instead of eating dinner. She has no significant past medical history and is not on any medications. Which of the following is the best course of treatment in this patient?", "answer": "Trazodone", "options": {"A": "Diazepam", "B": "St. John’s Wort", "C": "Paroxetine", "D": "Zolpidem", "E": "Trazodone"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 37-year-old female with a history of type II diabetes mellitus presents to the emergency department complaining of blood in her urine, left-sided flank pain, nausea, and fever. She also states that she has pain with urination. Vital signs include: temperature is 102 deg F (39.4 deg C), blood pressure is 114/82 mmHg, pulse is 96/min, respirations are 18, and oxygen saturation of 97% on room air. On physical examination, the patient appears uncomfortable and has tenderness on the left flank and left costovertebral angle. Which of the following is the next best step in management?", "answer": "Obtain a urine analysis and urine culture", "options": {"A": "Obtain an abdominal CT scan", "B": "Obtain blood cultures", "C": "Obtain a urine analysis and urine culture", "D": "Begin intravenous treatment with ceftazidime", "E": "No treatment is necessary"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 19-year-old boy presents with confusion and the inability to speak properly. The patient's mother says that, a few hours ago, she noticed a change in the way he talked and that he appeared to be in a daze. He then lost consciousness, and she managed to get him to the hospital. She is also concerned about the weight he has lost over the past few months. His blood pressure is 80/55 mm Hg, pulse is 115/min, temperature is 37.2°C (98.9°F), and respiratory rate is 18/min. On physical examination, the patient is taking rapid, deep breaths, and his breath has a fruity odor. Dry mucous membranes and dry skin are noticeable. He is unable to cooperate for a mental status examination. Results of his arterial blood gas analysis are shown.\nPco2 16 mm Hg\nHCO3–  10 mEq/L\nPo2 91 mm Hg\npH 7.1\nHis glucose level is 450 mg/dL, and his potassium level is 4.1 mEq/L. Which of the following should be treated first in this patient?", "answer": "Hypoperfusion", "options": {"A": "Hypoperfusion", "B": "Hyperglycemia", "C": "Metabolic acidosis", "D": "Hypokalemia", "E": "Hypophosphatemia"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 41-year-old woman presents to her primary care physician with complaints of fatigue and weakness. She denies any personal history of blood clots or bleeding problems in her past, but she says that her mother has had to be treated for breast cancer recently and is starting to wear her down. Her past medical history is significant for preeclampsia, hypertension, polycystic ovarian syndrome, and hypercholesterolemia. She currently smokes 1 pack of cigarettes per day, drinks a glass of wine per day, and currently denies any illicit drug use. Her vital signs include: temperature, 36.7°C (98.0°F); blood pressure, 126/74 mm Hg; heart rate, 111/min; and respiratory, rate 23/min. On physical examination, her pulses are bounding and irregular, complexion is pale, but breath sounds remain clear. On examination, the physician finds diffuse skin pallor and orders a complete blood count. Her laboratory data demonstrate a hematocrit of 27.1%, MCV of 79 fL, and a reticulocyte count of 2.0%. The patient is diagnosed with anemia. Which of the following represents the most likely etiology of her anemia.", "answer": "Iron deficiency", "options": {"A": "Vitamin B12 deficiency", "B": "Folate deficiency", "C": "Iron deficiency", "D": "Infiltrative bone marrow process", "E": "Intravascular hemolysis"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 59-year-old woman with stage IV lung cancer comes to the physician because of progressively worsening weakness in the past 3 months. She has had a 10.5-kg (23-lb) weight loss during this period. Her BMI is 16 kg/m2. She appears thin and has bilateral temporal wasting. Which of the following is the most likely primary mechanism underlying this woman's temporal muscle atrophy?", "answer": "Proteasomal degradation of ubiquitinated proteins", "options": {"A": "Lysosomal degradation of endocytosed proteins", "B": "Cytochrome c-mediated activation of proteases", "C": "Lipase-mediated degradation of triglycerides", "D": "TNF-α-mediated activation of caspases", "E": "Proteasomal degradation of ubiquitinated proteins"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 67-year-old man presents to the emergency department with a fever and altered mental status. The patient has a history of Alzheimer dementia and is typically bed bound. His son found him confused with a warm and flushed complexion thus prompting his presentation. The patient has a past medical history of dementia, diabetes, and hypertension and typically has a visiting home nurse come to administer medications. Prior to examination, he is given haloperidol and diphenhydramine as he is combative and will not allow the nurses near him. His temperature is 102.9°F (39.4°C), blood pressure is 104/64 mmHg, pulse is 170/min, respirations are 22/min, and oxygen saturation is 100% on room air. Physical exam is notable for dry and flushed skin and a confused man. There is no skin breakdown, and flexion of the patient’s neck elicits no discomfort. Laboratory studies are drawn as seen below.\n\nHemoglobin: 15 g/dL\nHematocrit: 45%\nLeukocyte count: 4,500/mm^3 with normal differential\nPlatelet count: 227,000/mm^3\n\nSerum:\nNa+: 139 mEq/L\nCl-: 100 mEq/L\nK+: 4.3 mEq/L\nHCO3-: 24 mEq/L\nBUN: 30 mg/dL\nGlucose: 97 mg/dL\nCreatinine: 1.5 mg/dL\nCa2+: 10.2 mg/dL\nAST: 12 U/L\nALT: 10 U/L\n\nUrine:\nColor: Yellow\nBacteria: Absent\nNitrites: Negative\nRed blood cells: Negative\n\nAn initial chest radiograph is unremarkable. The patient is given 3 liters of Ringer's lactate and an electric fan to cool off. Two hours later, his temperature is 99°F (37.2°C), blood pressure is 154/94 mmHg, pulse is 100/min, respirations are 17/min, and oxygen saturation is 100% on room air. The patient’s mental status is at the patient’s baseline according to the son. Which of the following is the most likely diagnosis?", "answer": "Non-exertional heat stroke", "options": {"A": "Exertional heat stroke", "B": "Neuroleptic malignant syndrome", "C": "Non-exertional heat stroke", "D": "Sepsis", "E": "Septic shock"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 32-year-old man presents to a mission hospital in Cambodia because he has had difficulty walking from his village to the market. He says that he has always been healthy other than occasional infections; however, over the last year he has been having numbness in his hands and feet. Furthermore, he has noticed weakness, muscle wasting, and pain in his lower extremities. The only change he can remember is that after having a poor harvest last year, he and his family have been subsisting on white rice. Physical exam reveals normal skin color and decreased deep tendon reflexes. The most likely cause of this patient's symptoms is associated with which of the following enzymatic reactions?", "answer": "Alpha-ketoglutarate dehydrogenase", "options": {"A": "Alpha-ketoglutarate dehydrogenase", "B": "Acyl transferases", "C": "Glycogen phosphorylase", "D": "Homocysteine methyltransferase", "E": "Succinate dehydrogenase"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 60-year-old woman presents to her primary care physician for a wellness checkup. She has a past medical history of hypertension and was discharged from the hospital yesterday after management of a myocardial infarction. She states that sometimes she experiences exertional angina. Her temperature is 99.5°F (37.5°C), blood pressure is 147/98 mmHg, pulse is 90/min, respirations are 17/min, and oxygen saturation is 98% on room air. Physical exam is within normal limits. Which of the following is the best next step in management?", "answer": "Atenolol", "options": {"A": "Atenolol", "B": "Furosemide", "C": "Hydrochlorothiazide", "D": "Nifedipine", "E": "Nitroglycerin"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 42-year-old male presents to his primary care physician complaining of abdominal pain. He reports a 5-month history of epigastric pain that improves with meals. He has lost 15 pounds since the pain started. His past medical history is significant for a prolactinoma for which he underwent transphenoidal resection. He drinks alcohol socially and has a 10 pack-year smoking history. His family history is notable for a maternal uncle with a parathyroid adenoma. His temperature is 98.8°F (37.1°C), blood pressure is 125/80 mmHg, pulse is 85/min, and respirations are 18/min. After further workup, the patient is started on octreotide, an analogue of an endogenously produced hormone. When this hormone is produced by the hypothalamus, it has which of the following effects?", "answer": "Decrease production of growth hormone", "options": {"A": "Decrease production of growth hormone", "B": "Decrease production of cholecystokinin", "C": "Decrease production of prolactin", "D": "Decrease production of gastrin", "E": "Decrease production of thyrotropin-releasing hormone"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 28-year-old female reports that, for more days than not over the past 3 years, she has felt \"down\" and, at times, \"mildly depressed.\" Over this period, she also endorses feeling fatigued, difficulty concentrating, and often sleeping more than in the past. The patient denies any manic or hypomanic periods and also reports that she did not have any periods of extreme worsening of her depressed mood beyond that described above. She also denies any suicidal ideation. What is the minimum amount of time this patient must exhibit these symptoms in order to meet the diagnostic criteria for dysthymia?", "answer": "2 years", "options": {"A": "2 months", "B": "6 months", "C": "1 year", "D": "2 years", "E": "5 years"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 42-year-old man is being treated by his female family medicine physician for chronic depression. Recently, he has been scheduling more frequent office visits. He does not report any symptoms or problems with his SSRI medication during these visits. Upon further questioning, the patient confesses that he is attracted to her and says \"You are the only one in the world who understands me\". The physician also manages his hypertension. Which of the following is the most appropriate next step in management?", "answer": "Ask closed-ended questions and use a chaperone for future visits", "options": {"A": "Re-evaluate this patient for borderline personality disorder", "B": "Ask closed-ended questions and use a chaperone for future visits", "C": "Immediately tell this patient that you can not continue to treat him and avoid any further communication", "D": "Increase the dosage of this patient’s SSRI", "E": "Petition the medical ethics committee board that you wish to date this patient"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 51-year-old female presents with intermittent right upper quadrant discomfort. The physician suspects she is suffering from biliary colic and recommends surgery. Following surgery, brown stones are removed from the gallbladder specimen. What is the most likely cause of the gallstone coloring?", "answer": "E. coli infection; beta-glucoronidase release", "options": {"A": "E. coli infection; beta-glucoronidase release", "B": "Shigella infection; HMG-CoA reductase release", "C": "Shigella infection; beta-glucoronidase release", "D": "Bile supersaturated with cholesterol; beta-glucoronidase release", "E": "Ascaris lumbricoides infection; bile supersaturated with cholesterol"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 56-year-old man with known coronary artery disease presents to the emergency department complaining of chest discomfort and palpitations for 2 hours. On arrival, the vital signs include blood pressure 122/76 mm Hg, heart rate 180/min, respiratory rate 22/min, temperature 37.0℃ (98.6℉), and blood oxygen saturation (SpO2) 98% on room air. A 12-lead electrocardiogram demonstrated ST-segment elevation in the anterolateral leads. The troponin level was 0.8 ng/mL (normal 0–0.4 ng/mL). The patient declined primary percutaneous intervention and was treated with antifibrinolytics in the coronary care unit. After 1 hour of treatment, the patient loses consciousness and the blood pressure falls to 60/40 mm Hg. Cardiac monitoring shows the electrocardiogram (ECG) pattern in lead 2 shown below. What is the most likely cause of his condition?", "answer": "Monomorphic ventricular tachycardia", "options": {"A": "Premature ventricular contractions", "B": "Monomorphic ventricular tachycardia", "C": "Mitral regurgitation", "D": "Third-degree heart block", "E": "Acute pericarditis"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 16-year-old female high school student is brought to the physician by her parents for her repeated behavioral problems at home and school during the past 10 months. Her teachers describe her behavior as uncooperative and disruptive as she persistently refuses to answer questions, insults her teachers, and annoys her classmates on a daily basis. At home, her parents try to address her frequent violations of curfew, but attempts at discussing the issue often result in their daughter losing her temper and screaming at her parents. Her grades have deteriorated over the past year. She has no history of psychiatric illness. On questioning, the patient refuses to answer and frequently disrupts the physician’s conversation with the parents. Which of the following is the most likely diagnosis in this patient?", "answer": "Oppositional defiant disorder", "options": {"A": "Reactive attachment disorder", "B": "Conduct disorder", "C": "Antisocial personality disorder", "D": "Attention-deficit hyperactivity disorder", "E": "Oppositional defiant disorder"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 22-year-old man is brought to the emergency room with a penetrating stab injury to his left chest. He appears pale, drowsy, and diaphoretic. His pulse is feeble, systolic blood pressure is 86 mm Hg, the respirations are 22/min with an oxygen saturation of 88% at room air, and the temperature is 36.6°C (98.0°F). His jugular vein is distended. Chest auscultation reveals equal breath sounds bilaterally, with muffled heart sounds. Immediate IV fluid resuscitation is initiated. Which of the following findings indicates that the cause of shock is cardiogenic?", "answer": "High central venous pressure (CPV)", "options": {"A": "Urine output < 0.5 mL/kg/h", "B": "Elevated serum creatinine", "C": "High central venous pressure (CPV)", "D": "Arterial blood gas (ABG) showing base deficit and metabolic acidosis", "E": "White blood cell (WBC) count < 4000/mm3"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 56-year-old woman is brought to the physician by her husband because of a two-day history of fever, malaise, headaches, and confusion. She recently immigrated from rural China and her immunization status is unknown. Her temperature is 39.1°C (102.4°F). Physical examination shows nuchal rigidity and photophobia. Cerebrospinal fluid analysis shows a neutrophil count of 1,500/mm3. Cerebrospinal fluid cultured on Thayer-Martin agar and normal sheep blood agar shows no growth. However, when the sheep blood agar sample is heated, numerous non-hemolytic, opaque, cream-colored colonies grow. Which of the following characteristics best describes the most likely causal pathogen?", "answer": "Gram-negative coccobacillus", "options": {"A": "Gram-negative coccobacillus", "B": "Gram-negative, facultative intracellular bacillus", "C": "Gram-positive, lancet-shaped diplococcus", "D": "Gram-negative diplococcus", "E": "Gram-positive, facultative intracellular bacillus"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 35-year-old male presents to his primary care physician complaining of a one-month history of progressively worsening fatigue. He sought medical attention because this has affected his ability to complete his work as a graduate student. As a child, he was hospitalized for hemolytic uremic syndrome. His past medical history is also notable for diabetes mellitus and obesity. He takes metformin and glyburide. He does not smoke and drinks alcohol occasionally. His family history is notable for chronic lymphocytic leukemia in his paternal uncle and stroke in his father. His temperature is 99.9°F (37.7°C), blood pressure is 100/70 mmHg, pulse is 110/min, and respirations are 18/min. Physical examination reveals diffuse pallor. Hematologic labs are shown below:\n\nHemoglobin: 8.9 g/dL\nHematocrit: 24%\nLeukocyte count: 7,500 cells/mm^3 with normal differential\nPlatelet count: 180,000/mm^3\nMean corpuscular volume: 85 µm^3\nReticulocyte count: 0.4%\n\nHead and neck imaging is negative for neck masses. The pathogen associated with this patient’s condition is also known to cause which of the following?", "answer": "Erythema infectiosum", "options": {"A": "Kaposi’s sarcoma", "B": "Erythema infectiosum", "C": "Mononucleosis", "D": "Croup", "E": "Myocarditis"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 30-year-old man is brought to the doctor's office by his wife. She complains that over the past week there have been 3 episodes where he has fallen asleep while speaking with her. She mentioned that these events began a few months ago and have been increasing in frequency. She also says that his snoring has gotten to the point where she has a hard time sleeping next to him. When asked, the patient says that he frequently falls asleep while reading or watching television in the afternoons and feels refreshed after a short nap. The patient is worried because he sometimes hears people who aren’t in the room as he falls asleep. He is worried he might be “going crazy.” He has noticed that when his friends tell him a joke or he laughs at something on the TV, he drops whatever he’s holding and feels like his legs become weak. These episodes self-resolve in a few seconds. Examination shows a morbidly obese man in no acute distress. Which of the following is the best treatment for the most likely cause for this patient’s illness?", "answer": "Modafinil", "options": {"A": "Haldol", "B": "Modafinil", "C": "Taking longer naps", "D": "Continuous positive airway pressure", "E": "Changing bedtime to earlier in the evening"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 55-year-old homeless man presents to the emergency department acutely confused. The patient was found wandering the streets with an abnormal gait. The patient has a past medical history of alcohol and IV drug abuse. His temperature is 98.5°F (36.9°C), blood pressure is 103/61 mmHg, pulse is 120/min, respirations are 16/min, and oxygen saturation is 97% on room air. Physical exam is notable for a poorly kempt man with ataxic gait. Ophthalmoplegia is noted on cranial nerve testing, and he has decreased vibration sensation in the bilateral lower extremity. Dermatologic exam reveals perifollicular hemorrhages, bleeding gums, and many bruises along the patient’s upper and lower extremities. An initial ECG is notable for sinus tachycardia and the patient is given 2L of Ringer lactate. Laboratory values are ordered as seen below.\n\nHemoglobin: 8.0 g/dL\nHematocrit: 30%\nLeukocyte count: 3,500/mm^3 with normal differential\nPlatelet count: 192,000/mm^3\nMCV: 119 fL\n\nSerum:\nNa+: 139 mEq/L\nCl-: 100 mEq/L\nK+: 4.3 mEq/L\nHCO3-: 25 mEq/L\nBUN: 20 mg/dL\nGlucose: 47 mg/dL\nCreatinine: 1 mg/dL\nCa2+: 9.2 mg/dL\nMg2+: 1.2 mEq/L\nAST: 82 U/L\nALT: 70 U/L\n\nWhich of the following is the best next treatment for this patient?", "answer": "Thiamine", "options": {"A": "Dextrose", "B": "Folate", "C": "Magnesium", "D": "Thiamine", "E": "Vitamin C"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 61-year-old woman is brought to the emergency department because of crushing substernal chest pain at rest for the past 2 hours. She is diaphoretic. Her temperature is 37.5°C (99.5°F), pulse is 110/min, respirations are 21/min, and blood pressure is 115/65 mm Hg. An ECG shows ST elevation in I, aVL, and V2–V4. Coronary angiography shows an 80% stenosis in the left anterior descending artery. Which of the following is the most likely initial step in the pathogenesis of this patient's coronary condition?", "answer": "Endothelial cell dysfunction", "options": {"A": "Intimal smooth muscle cell migration", "B": "Intimal monocyte infiltration", "C": "Platelet activation", "D": "Endothelial cell dysfunction", "E": "Fibrous plaque formation"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 4-year-old boy presents to the office with his mother. She states that the patient has been complaining of pain in his scrotum with swelling, abdominal pain, and nausea for the last 2 or 3 days. On exam, the abdomen is soft and nontender to palpation. The right scrotal sac is mildly enlarged without erythema. A tender mass is palpated in the right scrotal area. The mass does not transilluminate when a penlight is applied. The patient is afebrile and all vital signs are stable. What is the most likely etiology of this patient’s presentation?", "answer": "Patent processus vaginalis", "options": {"A": "Patent processus vaginalis", "B": "Engorgement of the pampiniform plexus", "C": "Collection of fluid in the tunica vaginalis", "D": "Infection of the epididymis", "E": "Neoplasm of the testicle"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 59-year-old man presents to his primary care physician, accompanied by his wife, who requests treatment for his “chronic pessimism.” The patient admits to feeling tired and “down” most of the time for the past several years but insists that it is “just part of getting old.” His wife believes that he has become more self-critical and less confident than he used to be. Neither the patient nor his wife can identify any stressors or triggering events. He has continued to work as a librarian at a nearby college during this time and spends time with friends on the weekends. He sleeps 7 hours per night and eats 3 meals per day. He denies suicidal ideation or periods of elevated mood, excessive irritability, or increased energy. Physical exam reveals a well-dressed, well-groomed man without apparent abnormality. Basic neurocognitive testing and labs (CBC, BMP, TSH, cortisol, testosterone, and urine toxicology) are within normal limits. What is the most likely diagnosis?", "answer": "Dysthymia", "options": {"A": "Adjustment disorder with depressive features", "B": "Bipolar disorder", "C": "Cyclothymia", "D": "Dysthymia", "E": "Major depressive disorder"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 17-month-old girl was brought to the emergency department by her mom following a fall. The mom reports that the patient was playing in the playground when she tripped and fell onto the mulch. She had an uncomplicated birth history and has been meeting developmental goals except for language delay, for which she is to receive a hearing test for further evaluation next week. Physical exam reveals bruising along the left lateral thigh, knee, and elbow; all lab tests are within normal limits. Radiograph shows a fracture of the olecranon. Serum chemistry and liver panels were within normal limits. What is the most likely explanation for the patient’s presentation?", "answer": "Defective type 1 collagen gene", "options": {"A": "Accidental trauma", "B": "Child abuse", "C": "Defective type 1 collagen gene", "D": "Low levels of phosphate", "E": "Low levels of vitamin D"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "ِA 62-year-old man comes to the emergency department because of colicky pain in the lower abdomen and abdominal distension for the past 12 hours. He has chronic constipation for which he takes lactulose and senna laxatives. His temperature is 37.1°C (98.7°F), blood pressure is 110/60 mm Hg and pulse is 85/min. On physical examination, there is diffuse abdominal distension and tenderness, and bowel sounds are faint. His plain abdominal radiograph is shown. Which of the following is the most likely diagnosis?", "answer": "Volvulus", "options": {"A": "Intussusception", "B": "Infectious colitis", "C": "Bowel adhesions", "D": "Volvulus", "E": "Acute diverticulitis"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 73-year-old African American man comes to the physician for a routine health maintenance examination. He has type 2 diabetes mellitus, hypertension, hypercholesterolemia, and coronary artery disease. His current medications include metformin, hydrochlorothiazide, amlodipine, rosuvastatin, isosorbide mononitrate, aspirin, and dipyridamole. He is 180 cm (5 ft 11 in) tall and weighs 110 kg (242 lb); BMI is 34 kg/m2. His vital signs are within normal limits. His hemoglobin A1c concentration is 6.7%. Serum lipid studies show:\nCholesterol, total 302 mg/L\nHDL-cholesterol 39 mg/dL\nLDL-cholesterol 197 mg/dL\nTriglycerides 292 mg/dL\nThe physician prescribes a drug that inhibits intestinal cholesterol absorption. The addition of this drug is most likely to increase the risk of which of the following adverse effects?\"", "answer": "Hepatotoxicity", "options": {"A": "Hepatotoxicity", "B": "Hyperkalemia", "C": "Cutaneous flushing", "D": "Hyperuricemia", "E": "Cholelithiasis"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 15-year-old girl is brought to the clinic by her mother because she is worried the patient has not yet had her period. The patient’s older sister had her first period at age 14. The mother had her first period at age 13. The patient reports she is doing well in school and is on the varsity basketball team. Her medical history is significant for asthma and atopic dermatitis. Her medications include albuterol and topical triamcinolone. The patient’s temperature is 98°F (36.7°C), blood pressure is 111/72 mmHg, pulse is 65/min, and respirations are 14/min with an oxygen saturation of 99% on room air. Her body mass index (BMI) is 19 kg/m^2. Physical exam shows absent breast development and external genitalia at Tanner stage 1. Serum follicle stimulating hormone (FSH) level is measured to be 38 mIU/mL. Which of the following is the next best diagnostic step?", "answer": "Karotype", "options": {"A": "CYP17 gene work-up", "B": "Estrogen levels", "C": "Gonadotrophin-releasing hormone stimulation test", "D": "Karotype", "E": "Luteinizing hormone levels"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 15-month-old girl is brought to the physician by her mother for grossly bloody diarrhea for 2 days. The girl has had a few episodes of blood-tinged stools over the past 3 weeks. She has not had pain, nausea, or vomiting. She is at the 55th percentile for height and 55th percentile for weight. Examination shows conjunctival pallor. The abdomen is soft and nontender. There is a small amount of dark red blood in the diaper. Her hemoglobin concentration is 9.5 g/dL, mean corpuscular volume is 68 μm3, and platelet count is 300,000/mm3. Further evaluation is most likely to show which of the following findings?", "answer": "Ectopic gastric mucosa on Technetium-99m pertechnetate scan", "options": {"A": "Cobblestone mucosa on colonoscopy", "B": "Neutrophil infiltrated crypts on colonic biopsy", "C": "Absent ganglionic cells on rectal suction biopsy", "D": "Target sign on abdominal ultrasound", "E": "Ectopic gastric mucosa on Technetium-99m pertechnetate scan"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 3855-g (8-lb 8-oz) newborn is examined shortly after birth. She was delivered at 40 weeks' gestation by cesarean delivery because of breech presentation. Pregnancy was otherwise uncomplicated. Physical examination shows asymmetric thigh creases. The left leg is shorter than the right leg and positioned in external rotation. Which of the following is the most likely underlying cause of this patient's findings?", "answer": "Abnormal development of the acetabulum", "options": {"A": "Avascular necrosis of the femoral head", "B": "Fracture of the femoral neck", "C": "Inflammation of the hip synovium", "D": "Abnormal development of the acetabulum", "E": "Displacement of the femoral epiphysis"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 27-year-old G1P0 woman at 9 weeks estimated gestational age presents for a prenatal visit. She has no current complaints and takes no medications. She is vegetarian and emigrated from Nepal 7 years ago. She does not use tobacco, alcohol or recreational drugs. The patient’s vital signs include: blood pressure 111/95 mm Hg, temperature 36.7°C (98.6°F), pulse 88/min. Laboratory results are significant for the following:\nHemoglobin 10.2 g/dL\nErythrocyte count 5.5 million/mm3\nMean corpuscular volume 65 μm3\nMean corpuscular hemoglobin 21 pg/cell\nRed cell distribution width 13.5% (ref: 11.5–14.5%)\nSerum ferritin 170 ng/mL\nWhich of the following is the most likely cause of this patient's anemia?", "answer": "Thalassemia trait", "options": {"A": "Vitamin B12 deficiency", "B": "Zinc deficiency", "C": "Gestational anemia", "D": "Iron deficiency anemia", "E": "Thalassemia trait"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 31-year-old woman presents to your clinic with a persistent headache. She reports she has suffered from headaches since the age of 27 when she gained 12 kg (26.4 lb) after the birth of her second child. The headache is generalized and throbbing in nature. It worsens in the morning and is aggravated with coughing, laughing, and sneezing. The patient’s blood pressure is 130/85 mm Hg, heart rate is 90/min, respiratory rate is 14/min, and the temperature is 36.6℃ (97.9℉). The patient’s weight is 101 kg (222.7 lb), height is 165 cm (5.4 ft), and BMI is 36.7 kg/m2. Examination reveals papilledema. Head CT scan does not reveal any abnormalities. Lumbar puncture shows an opening pressure of 32 cm H2O. The patient is prescribed a carbonic anhydrase inhibitor, acetazolamide, for idiopathic intracranial hypertension. What will be the change in the kinetics of the reaction catalyzed by carbonic anhydrase under the influence of acetazolamide?", "answer": "Activation energy (Ea) will increase", "options": {"A": "Activation energy (Ea) will increase", "B": "Activation energy (Ea) will decrease", "C": "Free energy (G) of the reaction products will increase", "D": "Free energy (G) of the reactants will increase", "E": "Increase reaction free energy change (∆G) by increasing free energy (G) of reactants and decreasing G of products"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 55-year-old man comes to the emergency department because of a dry cough and severe chest pain beginning that morning. Two months ago, he was diagnosed with inferior wall myocardial infarction and was treated with stent implantation of the right coronary artery. He has a history of hypertension and hypercholesterolemia. His medications include aspirin, clopidogrel, atorvastatin, and enalapril. His temperature is 38.5°C (101.3°F), pulse is 92/min, respirations are 22/min, and blood pressure is 130/80 mm Hg. Cardiac examination shows a high-pitched scratching sound best heard while sitting upright and during expiration. The remainder of the examination shows no abnormalities. An ECG shows diffuse ST elevations. Serum studies show a troponin I of 0.2 ng/mL (N < 0.01). Which of the following is the most likely cause of this patient's symptoms?", "answer": "Dressler syndrome", "options": {"A": "Cardiac tamponade", "B": "Constrictive pericarditis", "C": "Reinfarction", "D": "Early infarct-associated pericarditis", "E": "Dressler syndrome"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 27-year-old man presents to the physician with concern for pain in both of his knees that he is unable to attribute to any activities that he has recently performed. He had an acute episode of diarrhea 2 weeks ago, prior to the onset of symptoms. He has also been experiencing a burning sensation during urination for the past week. When questioned about any other symptoms, he notes that he has also noticed that his eyes occasionally feel irritated and painful, leading to bouts of blurry vision. On physical examination, the patient is afebrile and has conjunctival injection surrounding the iris. A synovial fluid aspiration of the knee is performed and reveals a white blood cell count of 51,000/µL. Which of the following is the most appropriate treatment for this patient’s condition?", "answer": "Indomethacin", "options": {"A": "Acetaminophen", "B": "Allopurinol", "C": "Colchicine", "D": "Indomethacin", "E": "Leflunomide"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 22-year old active duty soldier presents to your clinic with complaints of intense fatigue, fevers, abdominal pain, and a nonproductive cough. Her symptoms began a few days ago, but she returned from a tour of duty in Malawi and Mozambique four weeks ago. She endorses sleeping outside, using minimal bug spray, and swimming in rivers during her tour. On physical exam, her temperature is 101.5, and she appears exhausted. She has a hive-like rash scattered over her body. Her abdominal exam is notable for hepatosplenomegaly, and her lung exam is notable for scattered crackles. Her CBC with diff is remarkable for marked eosinophilia, and she has an elevated IgE. Of the following organisms, infection with which one is most consistent with her symptoms?", "answer": "Schistosoma mansoni", "options": {"A": "Plasmodium falciparum", "B": "Schistosoma mansoni", "C": "Plasmodium vivax", "D": "Mycobacterium tuberculosis", "E": "Trypanosoma brucei rhodesiense"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 72-year-old man comes to the emergency room because of a 4-day history of progressively worsening pain and swelling on the right side of his face. The patient was diagnosed with multiple myeloma 8 months ago and is currently undergoing treatment. His vital signs are within normal limits. Physical exam shows erythema and swelling over the right cheek and mandible. An orofacial fistula is present. Which of the following best describes the mechanism of action of the drug that is most likely responsible for this patient's symptoms?", "answer": "Binding to hydroxyapatite", "options": {"A": "Inhibition of angiogenesis", "B": "Cross-linking DNA at guanine", "C": "Inhibition of proteosome activity", "D": "Stimulation of PTH receptor", "E": "Binding to hydroxyapatite"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 12-month-old girl is brought to the physician because she is unable to sit and has not learned how to crawl. She keeps her hips and elbows flexed and her parents have to use considerable force to passively extend her joints. She attained neck control at 4 months and could roll from front to back at 5 months of age. She does not engage in play, reach for toys, or maintain eye contact. She babbles and does not mimic sounds. She does not follow simple instructions. She has difficulty swallowing solid foods and often coughs at meal times. Her maternal cousin has Down syndrome. Her vital signs are within normal limits. She is at the 25th percentile for length and 10th percentile for weight. Neurological examination shows increased muscle tone in all extremities. The ankle clonus and extensor plantar responses are present bilaterally. The Moro reflex is present. An MRI of the head shows periventricular leukomalacia. Which of the following is the most important risk factor for the development of this condition?", "answer": "Premature birth", "options": {"A": "Maternal smoking during pregnancy", "B": "Premature birth", "C": "Congenital rubella infection", "D": "Congenital CMV infection", "E": "Advanced maternal age"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 31-year-old male presents with a 2-day history of watery diarrhea that began 8 days after his arrival from Africa. None of the other members of his family became ill. He reports symptoms of malaise, anorexia, and abdominal cramps followed by watery diarrhea. He denies tenesmus, urgency, and bloody diarrhea. His temperature is 98.6°F (37°C), respiratory rate is 15/min, pulse is 107/min, and blood pressure is 90/68 mm Hg. A physical examination is performed and is within normal limits. Intravenous fluids are started, and a stool sample is sent to the lab, which comes out to be negative for any ova/parasites, blood cells, or pus cells. What is the most likely diagnosis?", "answer": "Traveler’s diarrhea due to ETEC", "options": {"A": "Giardiasis", "B": "C. difficile colitis", "C": "Irritable bowel syndrome (IBS)", "D": "Traveler’s diarrhea due to Norovirus", "E": "Traveler’s diarrhea due to ETEC"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 46-year-old woman presents to the emergency department with progressive dyspnea and chest pain. She reports that her symptoms started 1 week ago and have gotten progressively worse. The chest pain is left-sided and is exacerbated by coughing or deep breaths. She also endorses a 6-month history of joint pains involving her knees, elbows, and digits. She does not have a significant medical or surgical history. She takes ibuprofen as needed. She works as a pre-school teacher. The patient’s temperature is 99°F (37.2°C), blood pressure is 120/78 mmHg, pulse is 89/min, and respirations are 17/min with an oxygen saturation of 93% on room air. On physical examination, a friction rub upon inspiration/expiration and crackles are appreciated at the base of the left lung. She has an erythematous rash that spans the bilateral cheeks and nose. There are also scattered ecchymoses on her arms and legs. A chest radiograph shows a small left-sided pleural effusion. A complete blood count is obtained, as shown below:\n\nHemoglobin: 9 g/dL\nHematocrit: 28%\nLeukocyte count: 1,500/mm^3 with normal differential\nPlatelet count: 80,000/mm^3\n\nA urinalysis shows elevated protein levels. Serologic antibodies are pending. Which of the following is the primary cause of the patient’s lab results?", "answer": "Immune-mediated destruction", "options": {"A": "Hematologic malignancy", "B": "Immune-mediated destruction", "C": "Mechanical shearing", "D": "Splenic sequestration", "E": "Viral infection"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 48-year-old patient is recovering from acute lung injury following a diffuse pulmonary viral infection. The cell type responsible for the regeneration of the patient's alveolar epithelium is also functions in:", "answer": "Surfactant secretion", "options": {"A": "Protease release", "B": "Phagocytosis", "C": "Mucus secretion", "D": "Surfactant secretion", "E": "Recruitment of neutrophils"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 36-year-old woman comes to the physician because of fatigue for 4 months. She is unable to do her chores and complains of excessive sleepiness during the day. She has generalized itching. She has not had abdominal pain, fever, or weight loss. She has had chronic low back pain for 6 years. Her current medications include acetaminophen and vitamin supplements. Examination shows scratch marks over the trunk. The remainder of the examination shows no abnormalities. Laboratory studies show:\nHemoglobin 13.2 g/dL\nLeukocyte count 8,300/mm3\nPlatelet count 280,000/mm3\nESR 32 mm/h\nSerum\nGlucose 89 mg/dL\nCreatinine 0.7 mg/dL\nTSH 4.8 μU/ml\nBilirubin\nTotal 1.4 mg/dL\nDirect 0.9 mg/dL\nAlkaline phosphatase 480 U/L\nAspartate aminotransferase 62 U/L\nAlanine aminotransferase 32 U/L\nTotal cholesterol 288 mg/dL\nHDL-cholesterol 57 mg/dL\nLDL-cholesterol 189 mg/dL\nTriglycerides 212 mg/dL\nγ-Glutamyl transferase 92 U/L (N = 5–50)\nAntimitochondrial antibody (AMA) positive\nAntinuclear antibody (ANA) positive\nUrinalysis shows no abnormalities. Ultrasound of the abdomen shows gallbladder sludge. Which of the following is the most appropriate next step in management?\"", "answer": "Ursodeoxycholic acid", "options": {"A": "Liver biopsy", "B": "Atorvastatin", "C": "Cholestyramine", "D": "Endoscopic retrograde cholangiopancreatography", "E": "Ursodeoxycholic acid"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 40-year-old woman presents to the physician with complaints of frequent headaches and fatigue for a month. Her headaches are mild and occur at random times. They are relieved by over the counter analgesics. Furthermore, she feels tired most of the time and sometimes gets short of breath with exertion. She denies low mood, loss of interest, inability to concentrate, sleep disturbance, or suicidal ideation. She was diagnosed with Crohn’s disease 20 years ago for which she currently takes methotrexate. Additionally, she takes a folic acid-containing multivitamin daily. Her medical history is otherwise insignificant and she does not smoke, drink, or use recreational drugs. She has a pulse rate of 110/min, respiratory rate of 20/min, and temperature of 37.0°C (98.6°F). Physical examination reveals pallor in her palms and lower palpebral conjunctiva. Which of the following arterial blood findings for the partial pressure of oxygen (PaO2), oxygen saturation (SaO2), and oxygen concentration (CaO2) are expected in this patient?", "answer": "Normal PaO2, normal SaO2, low CaO2", "options": {"A": "Normal PaO2, normal SaO2, normal CaO2", "B": "Low PaO2, low SaO2, low CaO2", "C": "Low PaO2, normal SaO2, normal CaO2", "D": "Normal PaO2, normal SaO2, low CaO2", "E": "High PaO2, normal SaO2, normal CaO2"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 25-year-old woman complains of dyspnea and mild chest pain on exertion, which increases gradually with continued exertion. She had similar symptoms last year and her medical record included the following arterial blood gas findings:\npH 7.51\npO2 77 mm Hg\npCO2  32 mm Hg\nAn ECG last year demonstrated a right axis deviation. The current chest X-ray showed enlarged pulmonary arteries but no parenchymal inﬁltrates. A lung perfusion scan revealed a low probability for pulmonary thromboembolism. The current ECG showed right heart strain but no evidence of primary cardiac disease. What is the most logical diagnostic test for this patient?", "answer": "Echocardiography", "options": {"A": "PET scan of the heart", "B": "Echocardiography", "C": "Holter monitoring", "D": "Lung biopsy", "E": "Transbronchial biopsy"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 4-year-old boy is brought to the physician because of a progressive rash for 2 days. The rash started behind the ears and now involves the trunk and extremities. Over the past 4 days, he has had mild sore throat, red, itchy eyes, and headache. He was born at term and has been healthy except for recurrent episodes of tonsillitis and occasional asthma attacks. Two weeks ago, he was treated for tonsillitis that resolved with penicillin therapy. He immigrated with his family from Brazil 3 weeks ago. His immunization status is unknown. The patient appears weak and lethargic. His temperature is 38°C (100.4°F), pulse is 100/min, and blood pressure is 100/60 mm Hg. Examination shows postauricular and suboccipital lymphadenopathy. There is a non-confluent, pink maculopapular rash over the torso and extremities. His palms and soles show no abnormalities. Which of the following is the most likely diagnosis?", "answer": "Rubella", "options": {"A": "Measles", "B": "Rubella", "C": "Allergic drug reaction", "D": "Scarlet fever", "E": "Erythema infectiosum"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 66-year-old man presents to the office complaining of fatigue. He reports that for the past year he has been experiencing a progressive decrease in energy. This week he began having some difficulty breathing while climbing the stairs. He denies chest pain or palpitations. He has no other chronic medical conditions and has had no prior surgeries. The patient is found to be anemic. A fecal occult blood test is positive, and a colonoscopy is obtained. The patient is subsequently diagnosed with colorectal cancer. He undergoes a partial colectomy and is started on 5-fluorouracil as adjuvant chemotherapy. Which of the following should be monitored as the patient continues treatment?", "answer": "Neutrophil count", "options": {"A": "Creatinine", "B": "Fecal leukocytes", "C": "Monofilament testing", "D": "Neutrophil count", "E": "Peak flow"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 15-year-old girl comes to the physician for a follow-up evaluation. She has multiple erythematous pustules and nodules over her face, for which she has received erythromycin and topical benzoyl peroxide. She is concerned that the therapy is ineffective. The physician recommends a drug on the condition that the patient agrees to use oral contraceptives. The molecular structure of the drug most likely recommended by the physician closely resembles a drug used to treat which of the following conditions?", "answer": "Acute promyelocytic leukemia", "options": {"A": "EGFR-positive non-small cell lung cancer", "B": "Acute promyelocytic leukemia", "C": "BRAF-positive metastatic melanoma", "D": "HER2-positive gastric cancer", "E": "Choriocarcinoma"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 62-year-old female presents to her primary care provider complaining of a mass near her right jaw. She reports that the mass is painless and has grown very slowly over the past six months. She initially did not see a physician due to being very busy at her work as a lawyer. However, she reports that she noticed some right-sided facial weakness in the past week which prompted her to visit the physician. Her past medical history is notable for Hodgkins lymphoma as a child which required radiation therapy to the neck. She has a 20 pack-year smoking history and drinks alcohol socially. Her temperature is 98.6°F (37°C), blood pressure is 120/85 mmHg, pulse is 85/min, and respirations are 18/min. Physical examination reveals a painless firm mass at the angle of the right jaw. There is also a small palpable firm mass beneath the floor of the mouth. A right facial droop along with an inability to elevate her right eyebrow is noted. A biopsy of one of this lesion would most likely reveal which of the following?", "answer": "Cystic configurations of anaplastic squamous and mucoid cells", "options": {"A": "Cystic configurations of anaplastic squamous and mucoid cells", "B": "Non-infiltrative clusters of epithelial and mesenchymal cells", "C": "Epithelial cells with dense lymphoid stroma and germinal centers", "D": "Large basophilic binucleate cells", "E": "Uniform spindle cells with scant cytoplasm and cigar-shaped nuclei"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 29-year-old woman presents with low-grade fever, rash, and joint pain. She says her symptoms started gradually about 3 months ago and have progressively worsened. The patient describes her rash as pruritic, flat, and localized to her face. She reports a different type of rash on her shoulders and arms that are aggravated by exposure to sunlight. She describes her joint pain as moderate, dull and aching in character, and present mainly in the small bones of her wrists and hands, worse on the right than the left. She has no other relevant medical history and takes no current medications. Her family history is notable for her maternal grandmother, who had an unknown autoimmune condition. The patient denies any smoking history, alcohol use, or recreational drug use. Her temperature is 38.0℃ (100.3℉), pulse is 59/min, respiratory rate is 19/min, and blood pressure is 129/84 mm Hg. On physical examination, there is a macular, erythematous rash that involves both cheeks and the bridge of her nose, sparing the nasolabial folds. There is also a mild macular rash on the sun-exposed areas of her upper extremities and shoulders. She has moderate to severe point tenderness in the small joints of her wrists and hands, worse on the right, with minimal erythema and swelling. Multiple painless ulcers are present on the soft and hard palate. Which of the following additional findings would most likely be present in this patient?", "answer": "Swelling and proliferation of endothelial and mesangial cells in portions of each glomerulus with neutrophil infiltration", "options": {"A": "Swelling and proliferation of endothelial and mesangial cells in portions of each glomerulus with neutrophil infiltration", "B": "Immunologically mediated destruction of the salivary glands", "C": "Abnormal accumulation of fibrous tissue in the skin and multiple organs", "D": "Failure of B cell precursors to mature into B cells", "E": "Amyloid deposits within the myocardium between the muscle fibers"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 3-year-old Cuban-American male has a history of recurrent Pseudomonas and Candida infections. Laboratory analysis reveals no electrolyte abnormalities. Examination of his serum shows decreased levels of IgG and CT scan reveals the absence of a thymus. The child likely has:", "answer": "Severe combined immunodeficiency syndrome", "options": {"A": "Severe combined immunodeficiency syndrome", "B": "X-linked agammaglobinemia", "C": "DiGeorge syndrome", "D": "Isolated IgA deficiency", "E": "Common variable immunodeficiency"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 7-year-old girl is brought to the physician for evaluation of recurrent epistaxis. Her mother reports that she bruises easily while playing. Her pulse is 89/min and blood pressure is 117/92 mm Hg. Examination shows multiple bruises in the upper and lower extremities. Laboratory studies show:\nPlatelet count 100,000/mm3\nProthrombin time 12 seconds\nPartial thromboplastin time 33 seconds\nBleeding time 13 minutes\nA peripheral blood smear shows enlarged platelets. Ristocetin assay shows no platelet aggregation. Which of the following is the most likely underlying cause of the patient's condition?\"", "answer": "Glycoprotein Ib deficiency", "options": {"A": "Glycoprotein Ib deficiency", "B": "Vitamin K deficiency", "C": "Factor VIII deficiency", "D": "Von Willebrand factor deficiency", "E": "ADAMTS13 deficiency"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 38-year-old woman comes to the emergency department because of progressive headache, blurry vision, and nausea for 1 day. Four days ago, she was diagnosed with a right middle ear infection. She appears lethargic. Her temperature is 39.1°C (102.3°F), and blood pressure is 148/95 mm Hg. Ophthalmologic examination shows bilateral swelling of the optic disc. The corneal reflex in the right eye is absent. Sensation to touch is reduced on the upper right side of the face. Serum studies show increased concentrations of fibrin degradation products. Which of the following is the most likely diagnosis?", "answer": "Cerebral venous thrombosis", "options": {"A": "Cerebral venous thrombosis", "B": "Hypertensive emergency", "C": "Subarachnoid hemorrhage", "D": "Idiopathic intracranial hypertension", "E": "Viral meningitis"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 35-year-old female presents to your office for a routine physical. She informs you that she is pregnant, and that the father of her child has Waardenburg’s syndrome. She asks you about common findings in Waardenburg’s syndrome. Which of the following features are not associated of Waardenburg’s syndrome?", "answer": "Conductive hearing loss", "options": {"A": "Heterochromia", "B": "Hair hypopigmentation", "C": "Conductive hearing loss", "D": "Lateral displacement of inner canthi", "E": "Broad nasal root"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 4-year-old boy is brought to the emergency department for evaluation after falling. He has fallen multiple times in the last year. His parents report that he did not walk until he was 18 months old. Examination shows a mildly swollen right ankle with no tenderness over the medial or lateral malleolus; range of motion is full with mild pain. He has marked enlargement of both calves. When standing up, the patient uses his hands against his knees and thighs to slowly push himself up into a standing position. Which of the following is the most likely underlying mechanism of this patient's fall?", "answer": "Absence of dystrophin protein", "options": {"A": "Loss of the ATM protein", "B": "Absence of dystrophin protein", "C": "Myotonin protein kinase defect", "D": "Arylsulfatase A deficiency", "E": "SMN1 gene defect"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 25-year-old man is brought to the emergency department with second- and third-degree burns covering 30% of the surface area of his body. He is alert and active. He has no personal or family history of serious illness. His temperature is 36.5°C (97.7°F), pulse is 62/min, respirations are 18/min, and blood pressure is 105/70 mm Hg. Pulse oximetry on 2 liters by nasal cannula shows an oxygen saturation of 98%. Intravenous fluids, intravenous and topical antibiotics, and intravenous pain medications are administered in the intensive care unit. Twenty-four hours later, the patient develops respiratory distress. Respirations are 30/min. There is an inspiratory stridor. The patient requires rapid sequence intubation. Administering succinylcholine during this procedure would most likely result in which of the following complications?", "answer": "Cardiac arrhythmia", "options": {"A": "Prolonged muscle weakness", "B": "Malignant hyperthermia", "C": "Bronchospasm", "D": "Cardiac arrhythmia", "E": "Respiratory depression"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 32-year-old woman presents to the emergency department with 2 hours of left-sided weakness. Her husband reports that she had been complaining of pain and swelling in her right calf for several weeks prior to this event. The couple had recently returned from a vacation in Europe. What ausculatory finding would explain the mechanism by which her more recent complaint occurred?", "answer": "Wide, fixed splitting of S2", "options": {"A": "Holosystolic murmur radiating to the axilla", "B": "Wide, fixed splitting of S2", "C": "Crescendo-decrescendo murmur heard loudest at the right second intercostal space", "D": "Holosystolic murmur that increases on inspiration", "E": "An S2 that splits during expiration"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 41-year-old woman presents with pain in her abdomen for the last couple of hours. She says pain is intermittent and localized to the right hypochondriac region. She admits to eating fatty foods this morning before the pain started. She also complains of nausea but has not vomited yet. She describes episodes with similar symptoms in the past after a fatty meal but were less severe. Past medical history is irrelevant. The vital signs include: heart rate 85/min, respiratory rate 16/min, temperature 37.6°C (99.6°F), and blood pressure 120/80 mm Hg. Physical examination is within normal limits. An abdominal ultrasound is pending. Which of the following hormones most likely is the cause of the postprandial aggravation of this patient's symptoms?", "answer": "Cholecystokinin", "options": {"A": "Somatostatin", "B": "Cholecystokinin", "C": "Gastrin", "D": "Pepsin", "E": "Secretin"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 53-year-old man comes to the physician because of a 1-day history of fever and chills, severe malaise, and cough with yellow-green sputum. He works as a commercial fisherman on Lake Superior. Current medications include metoprolol and warfarin. His temperature is 38.5°C (101.3°F), pulse is 96/min, respirations are 26/min, and blood pressure is 98/62 mm Hg. Examination shows increased fremitus and bronchial breath sounds over the right middle lung field. An x-ray of the chest shows consolidation of the right upper lobe. Which of the following is the most likely causal pathogen?", "answer": "Streptococcus pneumoniae", "options": {"A": "Pseudomonas aeruginosa", "B": "Mycoplasma pneumoniae", "C": "Streptococcus pyogenes", "D": "Haemophilus influenzae", "E": "Streptococcus pneumoniae"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 46-year-old man presents to his physician because of persistent pelvic and scrotal pain for the past month. He also has had occasional fevers, chills, dysuria, and increased urinary frequency over the last few months. He was prescribed trimethoprim and sulfamethoxazole for the urinary symptoms, but he is still having symptoms currently. He is sexually active with multiple male and female partners and uses condoms inconsistently. The patient has hypertension and takes lisinopril.  He also takes PrEP (Truvada, which contains tenofovir and emtricitabine). On physical exam, his temperature is 36.7℃ (98.1℉), the blood pressure is 115/70 mm Hg, the pulse is 74/min, and the respirations are 14/min. A digital rectal exam reveals a mildly tender and mildly enlarged prostate. Urine specimens are sent for culture and sensitivity testing. A urine sample taken after prostate massage shows a 10-fold increase in bacteria counts. The test results for antimicrobial sensitivity include ampicillin, cefepime, gentamicin, levofloxacin, and meropenem. The patient is prescribed tamsulosin. Which of the following is the most appropriate antibiotic to pair with the tamsulosin?", "answer": "Levofloxacin", "options": {"A": "Ampicillin", "B": "Cefepime", "C": "Gentamicin", "D": "Levofloxacin", "E": "Trimethoprim and sulfamethoxazole"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 29-year-old woman comes to the emergency department because of progressive numbness and weakness in her right arm and right leg for 1 day. Two months ago, she had blurry vision and headache for a week, which resolved without treatment. She does not smoke or drink alcohol. Her temperature is 37°C (98.6°F), pulse is 78/min, respirations are 14/min, and blood pressure is 115/71 mm Hg. Muscle strength is 3/5 in the right arm and leg and 5/5 on the left side. MRI of the brain shows gadolinium-enhancing lesions in the left central sulcus, cervical spinal cord, and optic nerve. Intravenous methylprednisolone therapy is started. This drug is most likely to result in which of the following laboratory changes?", "answer": "Eosinopenia", "options": {"A": "Basophilia", "B": "Monocytosis", "C": "Lymphocytosis", "D": "Eosinopenia", "E": "Granulocytopenia"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 30-year-old male biology graduate student was dismissed from his PhD program after 8 years because he was not able to produce a thesis, claiming that his data was never exactly how he wanted it. He would spend weeks planning out a simple experiment, since everything had to be just right. For many experiments, he would start over because he felt he went out of order in adding the reagents to his media for his cells. He has had similar problems in his undergraduate courses, often failing to complete his assignments on time because he had to revise them until they were perfect. Which of the following disorders does this patient potentially suffer from?", "answer": "Obsessive compulsive personality disorder", "options": {"A": "Schizoid personality disorder", "B": "Narcissistic personality disorder", "C": "Obsessive compulsive personality disorder", "D": "Paranoid personality disorder", "E": "Obsessive compulsive disorder"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 62-year-old male presents to his primary care physician complaining of an unintended 10-pound weight loss over the last 4 months. He also reports vague abdominal discomfort, weakness, and occasional yellowing of his skin and eyes. He has a history of cirrhosis secondary to alcohol abuse and hepatitis C infection. Physical exam demonstrates hepatomegaly and abdominal distention. Which of the following serum markers is most strongly associated with this patient’s condition?", "answer": "Alpha-fetoprotein (AFP)", "options": {"A": "Carcinoembryonic antigen (CEA)", "B": "Cancer antigen 125 (CA 125)", "C": "Cancer antigen 19-9 (CA 19-9)", "D": "Alpha-fetoprotein (AFP)", "E": "Beta-human chorionic gonadotropin (ß-HCG)"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A research group designed a study to investigate the epidemiology of syphilis in the United States. The investigators examined the total number of cases of syphilis and genitourinary chlamydia in the United States using a national health survey of a nationally representative sample of US citizens conducted in 2012. The investigators ultimately found that a history of genitourinary chlamydia infection is associated with syphilis. This study is best described as which of the following?", "answer": "Cross-sectional study", "options": {"A": "Meta-analysis", "B": "Single-blind clinical trial", "C": "Double-blind clinical trial", "D": "Cross-sectional study", "E": "Case-control study"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 56-year-old African American male presents with altered mental status, abdominal pain, and a fever of 100.4F. His past medical history is significant for alcohol use and cirrhosis of the liver. Shifting dullness is noted on physical exam. Paracentesis demonstrates serum ascites albumen gradient of 1.3 g/dL, and the ascitic fluid polymorphonuclear cell count is 280 cells/mm^3. Which of the following is the best treatment for this patient’s condition while waiting for the ascitic fluid culture results?", "answer": "Cefotaxime", "options": {"A": "Nadolol", "B": "Cefotaxime", "C": "Penicillin", "D": "Levofloxacin", "E": "Gentamicin"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 4-year-old boy who recently emigrated from Ghana is brought to the physician because of a 5-day history of pain and swelling in his hands. He has had similar episodes in the past. The patient appears distressed. His temperature is 38.1°C (100.5°F). Physical examination shows pallor. The dorsum of his hands and fingers are swollen, warm, and tender to palpation. Which of the following additional findings is most likely in this patient?", "answer": "Microhematuria", "options": {"A": "Coronary artery aneurysm", "B": "Hyperuricemia", "C": "Salmon-colored macules", "D": "Thickened heart valves", "E": "Microhematuria"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 47-year-old woman is admitted to the hospital because of a 2-week history of low-grade fever, fatigue, and a 3-kg (6.6-lb) weight loss. Her temperature is 38°C (100.4°F). Physical examination shows pallor and a cardiac murmur. Her serum creatinine is 1.8 mg/dL. Urinalysis shows red cell casts and 2+ protein. A CT scan of the abdomen with contrast shows no abnormalities. Despite appropriate medical therapy, the patient dies. A photograph of the heart taken during autopsy is shown. Which of the following is the most likely explanation for the laboratory findings in this patient?", "answer": "Deposition of antigen-antibody complexes", "options": {"A": "Occlusion of renal arteries by cholesterol crystals", "B": "Deposition of antigen-antibody complexes", "C": "Intravascular fragmentation of red blood cells", "D": "Hypersensitivity to penicillin haptens", "E": "Tubular cell damage by a nephrotoxic drug"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 36-year-old woman comes to the physician because of a 2-month history of progressively worsening lower back pain and weakness in the lower extremities. The pain is worse with movement and improves with lying down on a flat surface. She was diagnosed with pulmonary tuberculosis 6 months ago and is currently taking isoniazid and rifampin. Physical examination shows sensory loss over the lateral aspect of the mid-thigh, patella, and medial aspect of the right lower leg. Strength is 2/5 with right-sided dorsiflexion and the patellar reflex is absent. An x-ray of the spine shows a paravertebral opacity with anterior wedging of the vertebral body. Which of the following nerve roots is most likely to be affected in this patient?", "answer": "L4", "options": {"A": "L5", "B": "S2", "C": "S1", "D": "L3", "E": "L4"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 24-year-old primigravid woman at 8 weeks' gestation is brought to the emergency department because of a 5-day history of nausea and vomiting. She has not been able to tolerate much food or drink. Her symptoms are worse in the morning. She has tried multiple oral antiemetics with limited relief. She has not had fevers, chills, abdominal pain, urinary symptoms, or diarrhea. She appears tired. Her temperature is 37°C (98.6°F), pulse is 105/min, and blood pressure is 108/60 mm Hg. Examination shows dry mucous membranes and cool extremities, with delayed capillary refill time. Arterial blood gas analysis on room air shows:\npH 7.56\nPCO2 40 mm Hg\nPO2 94 mm Hg\nHCO3- 30 mEq/L\nMeasurement of which of the following is the most appropriate next step in diagnosis?\"", "answer": "Urine chloride concentration", "options": {"A": "Serum osmolal gap", "B": "Urine anion gap", "C": "Serum anion gap", "D": "Urine albumin to urine creatinine ratio", "E": "Urine chloride concentration"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 34-year-old pregnant woman, gravida 2, para 0, at 28 weeks of gestation presents to the physician for a prenatal visit. She has not had regular prenatal care. Her most recent abdominal ultrasound was at 20 weeks of gestation, and it confirmed accurate fetal dates and appropriate fetal development. She takes levothyroxine for hypothyroidism. She used to work as a nurse before she emigrated from Brazil 13 years ago. She lost her immunization records during the move and cannot recall all of her vaccinations. She appears well. Her vital signs are within normal limits. The physical examination reveals a fundal height of 26 cm. No abnormalities are found during the physical exam. An ELISA test conducted for HIV is negative. Serology test results for hepatitis B surface antibody and hepatitis C antibody are positive for both. The laboratory test results for hepatitis B core antibody, hepatitis B surface antigen, and hepatitis A antibody are negative. The polymerase chain reaction analysis of hepatitis C RNA is positive for genotype 1. Which of the following is the most appropriate recommendation at this time?", "answer": "Hepatitis A vaccination", "options": {"A": "Hepatitis A vaccination", "B": "Plan to formula feed the newborn", "C": "Schedule a cesarean delivery", "D": "Start combination therapy with interferon α and ribavirin", "E": "Undergo liver biopsy"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 36-year-old man presents with a 3-week history of fever, enlarged lymph nodes, fatigue, and a dry cough. The patient’s wife says she has noticed that he lost a lot of weight over the last 6 months and seems very pale. Over the last week, he has noticed a worsening non-productive cough and night sweats. His blood count shows anemia and low lymphocyte count. He tells the physician that he had multiple unprotected sexual relationships with women other than his wife about 6 years ago and is fearful this may be related to his current health concerns. A test is performed which screens for the cause of this patient's immunodeficiency. Which of the following does this screening test detect?", "answer": "p24 antigen", "options": {"A": "Anti-HCV antigen", "B": "Lactic dehydrogenase", "C": "p24 antigen", "D": "HIV viral load", "E": "CCR5 mutation"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "Seven days after initiation of induction chemotherapy for acute myeloid leukemia, a 56-year-old man develops leukopenia. He feels well. He has no history of serious cardiopulmonary disease. His temperature is 36.7°C (98.1°F), blood pressure is 110/65 mm Hg, pulse is 72/min, and respiratory rate is 14/min. Examination of the skin, head and neck, heart, lungs, abdomen, and perirectal area reveals no abnormalities. Laboratory studies show:\nHemoglobin 9 g/dL\nLeukocyte count 1,500/mm3\nPercent segmented neutrophils 50%\nPlatelet count 85,000/mm3\nTo reduce the likelihood of complications, it is most appropriate to administer which of the following?", "answer": "Ciprofloxacin", "options": {"A": "Caspofungin", "B": "Ciprofloxacin", "C": "Granulocyte colony-stimulating factor", "D": "Vancomycin", "E": "No pharmaco-prophylaxis at this time"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 40-year-old man undergoes an elective cholecystectomy for repeated attacks of cholelithiasis over the last 5 years. In the operating room, rapid sequence intubation is performed using a certain muscle relaxant to prevent aspiration of gastric contents. During the procedure, atracurium is administered to maintain muscle relaxation and, 1.5 hours after the operation, the anesthesiologist administers neostigmine to reverse the paralysis. The patient, however, continues to remain paralyzed and cannot be extubated. Which of the following drugs most likely caused prolonged muscle paralysis in this patient?", "answer": "Succinylcholine", "options": {"A": "Dantrolene", "B": "Midazolam", "C": "Pancuronium", "D": "Succinylcholine", "E": "Tubocurarine"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 12-year-old boy is brought to the emergency department by ambulance after he was struck by a car while crossing the road. He is found to have a femur fracture and multiple bruises on presentation, but he is alert and hemodynamically stable. He says that the car \"came out of nowhere\" and that he has had multiple similar near misses in recent months. He has no past medical history but says that he has been having headaches that he describes as dull and continuous. He has also noticed that he has been waking up at night several times to go to the restroom. Otherwise, he has been healthy with no major concerns. A basic metabolic panel shows mild hypernatremia. The most likely pathology underlying this patient's symptoms is derived from which of the following embryonic layers?", "answer": "Surface ectoderm", "options": {"A": "Endoderm", "B": "Mesoderm", "C": "Neural crest", "D": "Neuroectoderm", "E": "Surface ectoderm"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 40-year-old man presents with left hip pain. He says that symptoms started a month ago and have progressively worsened. He says the pain has rendered him unable to report to work for the last 2 weeks. The pain was initially 4/10 in intensity, dull with no radiation and was aggravated to 5/10 in intensity upon weight-bearing. Initially, it improved with rest and Tylenol. He initially attributed it to heavy work and took a few days off work, but he did not seek medical attention. However, it worsened over time to its present 8/10 intensity and does not respond to Tylenol anymore. The patient denies any history of injury, weight loss, change in appetite, or recent travel. His past medical history is significant for Crohn's disease, managed with a combination of prednisone and mesalamine and presently in remission. On physical examination, there is limited flexion and extension at the left hip. The rest of the examination, including a complete neurological examination, is unremarkable. On abdominal imaging of the left hip joint, a transcervical fracture is noted in the left hip with surrounding bony sclerosis. A DEXA scan shows a T-score of  -2.5 at the hips and -1.5 at the lumbar spine (normal T-score ≥ -1.0). Which of the following is most likely to be the underlying cause for the fracture in this patient?", "answer": "Chronic steroid use", "options": {"A": "Trauma", "B": "Chronic steroid use", "C": "Pott's disease", "D": "Metastatic lesion", "E": "Sciatica"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 78-year-old woman with a history of breast cancer, status-post bilateral mastectomy, presents to the emergency department with progressive difficulty breathing, worsening fatigue, and 5 pounds of unintended weight loss over the past month. A portable chest x-ray reveals a massive right pleural effusion. The ED resident performs thoracentesis with chest tube placement and admits her to the floor. Overnight, the patient requests multiple pain medications for right upper abdominal pain and is found to have increasingly sanguinous drainage. Where was the thoracentesis needle most likely placed?", "answer": "Lower border of the 10th rib at the right midaxillary line", "options": {"A": "Lower border of the 10th rib at the right midaxillary line", "B": "Lower border of the 9th rib at the right midaxillary line", "C": "Upper border of the 7th rib at the right midclavicular line", "D": "Upper border of the 9th rib at the right midaxillary line", "E": "Upper border of the 10th rib at the right midaxillary line"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "While studying the metabolism of a novel drug, the researcher identifies a molecule that inhibits its metabolism by binding with enzyme E. Molecule A inhibits the enzyme E by reversibly binding at the same active site on the enzyme where the drug binds. Which of the following statements best describes the effects of molecule A on Vmax and Km on the metabolic reactions of the novel drug?", "answer": "Value of Vmax is unchanged but value of Km is increased", "options": {"A": "Value of Vmax is unchanged but value of Km is increased", "B": "Value of Vmax is decreased but value of Km is unchanged", "C": "Values of both Vmax and Km are unchanged", "D": "Value of Vmax is decreased but value of Km is increased", "E": "Value of Vmax is unchanged but value of Km is decreased"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 70-year-old man presents to a physician’s office with shortness of breath for 1 month. He is “easily winded” and is unable to keep up with his grandchildren when playing in the park. Over the last few weeks, he had to increase the number of pillows under his head to sleep comfortably. He denies a cough and fever. The medical history includes hypercholesterolemia and hypertension. His current medications are aspirin, carvedilol, and rosuvastatin. The vital signs are as follows: blood pressure 150/90 mm Hg, pulse 90/min, and respiratory rate 14/min. The physical examination reveals distended jugular veins, bilateral pitting edema of the lower limbs, and fine crackles at the base of the lungs. An echocardiogram reveals an ejection fraction of 40%. Inhibition of which of the following hormones would be most beneficial for this patient?", "answer": "Angiotensin II", "options": {"A": "Angiotensin II", "B": "Prostaglandin E1", "C": "Aldosterone", "D": "Epinephrine", "E": "Antidiuretic hormone (ADH)"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 51-year-old man comes to the physician because of severe pain while urinating for 4 days. He has also had to urinate more often than usual. Three weeks ago, he underwent surgery for an incarcerated hernia. While recovering, he developed septic shock and was treated in the intensive care unit. He was discharged 6 days ago. He has a history of hypertension. Current medications include amlodipine and oxycodone. He appears anxious. His temperature is 37.8°C (100°F), pulse is 96/min, and blood pressure is 122/80 mm Hg. Examination shows tenderness to palpation in the suprapubic area; no guarding is present. There is a well-healed surgical scar in the right inguinal region. There is no costovertebral angle tenderness. Urinalysis shows:\nBlood 1+\nProtein 1+\nNitrite positive\nLeukocyte esterase positive\nRBC 1–2/hpf\nWBC 20–25/hpf\nWhich of the following would have most likely prevented this complication?\"", "answer": "Intermittent catheterization", "options": {"A": "Intermittent catheterization", "B": "Prophylactic oral ciprofloxacin", "C": "Topical mupirocin application", "D": "Use of a hydrophilic catheter", "E": "Screening for bacteriuria"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 40-year-old woman with HIV infection comes to the emergency department because of a 4-week history of progressively worsening fatigue and headache. On mental status examination, the patient is somnolent and oriented only to person. Her CD4+ lymphocyte count is 80/mm3 (N ≥ 500). Analysis of this patient's cerebrospinal fluid (CSF) shows a leukocyte count of 30/mm3 (60% lymphocytes), a protein concentration of 52 mg/dL, and a glucose concentration of 37 mg/dL. An India ink stain of the CSF is shown. Which of the following is the most appropriate pharmacotherapy for this patient's neurological symptoms?", "answer": "Amphotericin B and flucytosine", "options": {"A": "Pyrimethamine, sulfadiazine, and folinic acid", "B": "Isoniazid, rifampin, pyrazinamide, and ethambutol", "C": "Cefotaxime and ampicillin", "D": "Amphotericin B and flucytosine", "E": "Fluconazole"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 64-year-old man comes to the physician because of a 2-week history of intermittent epigastric discomfort. He reports that his urine has been very dark, and his stools have been pale for the past week. His appetite has decreased, and he has had a 4.5-kg (10-lb) weight loss during this period. He has smoked 1 pack of cigarettes daily for 30 years. He drinks a few shots of vodka daily. He has no history of severe illness. He has chronic left knee pain, for which he takes acetaminophen. Vital signs are within normal limits. Examination shows jaundice of the skin and scleral icterus. There are scratch marks on the extremities. Abdominal examination shows a nontender, palpable mass in the right upper quadrant. The remainder of the examination is normal. Laboratory studies show:\nHemoglobin 11.6 g/dL\nLeukocyte count 8,700/mm3\nPlatelet count 172,000/mm3\nSerum\nUrea nitrogen 17 mg/dL\nCreatinine 1.1 mg/dL\nBilirubin\nTotal 6 mg/dL\nDirect 5.2 mg/dL\nAlkaline phosphatase 220 IU/L\nUltrasonography shows dilated extrahepatic and pancreatic ducts and a distended gall bladder. Which of the following is the most likely cause of these findings?\"", "answer": "Malignant biliary tract obstruction", "options": {"A": "Malignant biliary tract obstruction", "B": "Acetaminophen-induced liver injury", "C": "Primary sclerosing cholangitis", "D": "Hemolysis", "E": "Chronic pancreatitis"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 27-year-old woman is brought to the physician after passing out at home. Her husband reports that she suddenly lost consciousness for approximately 30 seconds while shoveling snow in the driveway. Immediately before the episode, she felt light-headed and short of breath. Two months ago, she experienced a similar episode while running in her yard with her children. She has no history of serious illness. Her father died of sudden cardiac death at the age of 44 years. Vital signs are within normal limits. Cardiac examination shows a systolic ejection murmur best heard along the left sternal border that decreases with hand grip. The remainder of the examination shows no abnormalities. Which of the following is the most appropriate treatment for this patient?", "answer": "Metoprolol", "options": {"A": "Septal myectomy", "B": "Verapamil", "C": "Amlodipine", "D": "Cardiac pacemaker", "E": "Metoprolol"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 7-month-old male infant is brought to the physician because of a 2-month history of fatigue and weakness. His mother reports that he has difficulty feeding. He is at the 20th percentile for height and 3rd percentile for weight. Physical examination shows an enlarged tongue. Crackles are heard at both lung bases. The liver is palpated 1 cm below the right costal margin. Neurologic examination shows decreased muscle tone in the extremities. Serum glucose is 105 mg/dL. An x-ray of the chest shows cardiomegaly. The patient most likely has a deficiency of which of the following enzymes?", "answer": "Acid maltase", "options": {"A": "Acid maltase", "B": "Myophosphorylase", "C": "Iduronate sulfatase", "D": "Glucose-6-phosphatase", "E": "Alpha-galactosidase"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 43-year-old man presents to a medical office for follow-up of hypertension. He was recently diagnosed and has been managing his condition with diet modification and moderate-intensity exercise. Today, he brings a list of his recent at-home morning blood pressure readings. The systolic blood pressure readings over the last 5 days are as follows:\nDay 1: 130 mm Hg\nDay 2: 132 mm Hg\nDay 3: 128 mm Hg\nDay 4: 132 mm Hg\nDay 5: 128 mm Hg\nWhat is the standard deviation for the systolic blood pressure readings?", "answer": "2 mm Hg", "options": {"A": "1 mm Hg", "B": "1.5 mm Hg", "C": "4 mm Hg", "D": "2 mm Hg", "E": "2.5 mm Hg"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "An 11-year-old boy is brought to the physician by his mother because of worsening fatigue. His mother reports that he seems to have trouble keeping up with his older brothers when playing outside. Physical examination shows conjunctival pallor. A hemoglobin electrophoresis is performed. This patient's results are shown in comparison to those of a patient with known sickle cell anemia and a child with normal hemoglobin. Based on this electrophoresis, which of the following types of hemoglobin are dominant in this patient's blood?", "answer": "HbS and HbC", "options": {"A": "HbA and HbC", "B": "HbS only", "C": "HbA and HbF", "D": "HbA only", "E": "HbS and HbC"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 55-year-old African American man presents to the emergency department with central chest pressure. His symptoms started 1 day before. The pain was initially intermittent in nature but has become constant and radiates to his jaw and left shoulder. He also complains of some difficulty breathing. The patient was diagnosed with essential hypertension 1 year ago, but he is not taking any medications for it. The patient denies smoking, alcohol, or drug use. Family history is unremarkable. His blood pressure is 230/130 mm Hg in both arms, the temperature is 36.9°C (98.4°F), and the pulse is 90/min. ECG shows diffuse T wave inversion and ST depression in lateral leads. Laboratory testing is significant for elevated troponin. Which of the following is the most likely diagnosis?", "answer": "Hypertensive emergency", "options": {"A": "Aortic dissection", "B": "Hypertensive urgency", "C": "Hypertensive emergency", "D": "Aortic aneurysm", "E": "Malignant hypertension"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 38-year-old woman comes to the physician for the evaluation of progressive weakness and numbness for 3 months. The symptoms started in her lower legs and gradually moved to her upper legs and arms. During the last 5 days, she has also had bilateral facial weakness with headaches. She has hepatitis B and Graves' disease. She is sexually active with one male partner and they use condoms inconsistently. Her current medications include methimazole and a multivitamin. Vital signs are within normal limits. She is alert and fully oriented. She has bilateral upper and lower facial paralysis. There is generalized weakness of the muscles. Sensation to light touch is decreased throughout and is absent in her fingertips and toes. Deep tendon reflexes are 1+ bilaterally. Further evaluation of this patient is most likely to show which of the following findings?", "answer": "Positive GM1 ganglioside autoantibodies", "options": {"A": "Positive GM1 ganglioside autoantibodies", "B": "Positive Lyme ELISA test", "C": "Low vitamin B12 level", "D": "Elevated TSH and decreased FT4 levels", "E": "Elevated HbA1c level"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 32-year-old G2P1 at 32 weeks gestation presents to the emergency department with complaints of severe abdominal pain, fatigue, and nausea. Physical examination is significant for profound jaundice and tenderness to palpation of the right upper quadrant of the abdomen. The patient returned 2 weeks ago from a 1 month-long trip to India. She received sporadic pre-natal care while traveling and reports no known complications in her current pregnancy to date. She denies any past medical problems and states that her prior pregnancy proceeded as a normal vaginal birth without any complications. Infection with which of the following organisms would portend the worst prognosis with the highest mortality rate for this patient?", "answer": "Hepatitis E", "options": {"A": "Hepatitis A", "B": "Hepatitis B", "C": "Hepatitis C", "D": "Hepatitis D", "E": "Hepatitis E"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 42-year-old woman comes to the physician because of an episode of coughing with bloody sputum. Over the past 5 months, she has had a persistent nonproductive cough, excessive fatigue, and a 5.6-kg (12.3-lb) weight loss. She does not smoke. Physical examination shows no abnormalities. An x-ray of the chest shows a 2.0-cm nodule with irregular borders at the upper lobe of the left lung. A CT-guided biopsy of the lung nodule is performed. Pathologic examination of the biopsy specimen is most likely to show which of the following?", "answer": "Adenocarcinoma", "options": {"A": "Small cell lung carcinoma", "B": "Large cell lung carcinoma", "C": "Bronchial carcinoid tumor", "D": "Squamous cell lung carcinoma", "E": "Adenocarcinoma"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A group of researchers is conducting a prospective study to examine if dietary fiber intake is protective against coronary heart disease. Specifically, they are looking at the frequency of coronary heart incidents in a group of middle-aged men taking various daily amounts of water-insoluble fiber. The Pearson correlation coefficient that was obtained regarding the relationship between the amount of daily water-insoluble fiber intake and the frequency of coronary heart incidents in their study was 0.11 with a p-value of 0.006. Which of the following statements is correct regarding this study result?", "answer": "There is no correlation between fiber intake and the frequency of coronary heart incidents because the correlation coefficient is significant.", "options": {"A": "There is a significant correlation between the daily fiber intake and the frequency of coronary heart incidents because the correlation coefficient is significant.", "B": "There is a significant correlation between fiber intake and the frequency of coronary heart incidents because the correlation coefficient is not significant.", "C": "There is a significant correlation between fiber intake and the frequency of coronary heart incidents because the value of the correlation coefficient shows a very good and robust correlation.", "D": "There is no correlation between fiber intake and the frequency of coronary heart incidents because the correlation coefficient is significant.", "E": "There is no correlation between fiber intake and the frequency of coronary heart incidents because the correlation coefficient is not significant."}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 24-year-old man comes to the physician because of a painful swelling above his buttocks for 1 week. He is unable to sit for extended periods because of the pain. He has obstructive sleep apnea and type 2 diabetes mellitus. His only medication is metformin. He appears anxious. He is 175 cm (5 ft 9 in) tall and weighs 114 kg (251 lb); BMI is 37 kg/m2. His temperature is 38.1°C (100.6°F), pulse is 96/min and blood pressure is 124/86 mm Hg. Examination shows facial acne. A cyst is seen above the natal cleft. There is tenderness to palpation at the cyst and surrounding tissue. The skin around the cyst is warm and erythematous. Which of the following is the most appropriate next step in management?", "answer": "Incision and drainage", "options": {"A": "Tract curettage", "B": "Coccygectomy", "C": "Incision and drainage", "D": "Retinoid therapy", "E": "Surgical resection and primary wound closure"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 17-year-old girl comes to the physician because of a 3-year history of acne on her face and chest. She has no itching or scaling. She is concerned about the possibility of facial scarring and has never sought treatment. She has no history of serious illness. She takes no medications. She is 160 cm (5 ft 3 in) tall and weighs 58 kg (130 lb); BMI is 23 kg/m2. Her vital signs are within normal limits. Examination shows several open comedones on the face and chest. Which of the following is the most appropriate initial treatment?", "answer": "Topical benzoyl peroxide", "options": {"A": "Oral antibiotics", "B": "Topical benzoyl peroxide", "C": "Combined oral contraceptive", "D": "Topical antibiotic", "E": "Oral isotretinoin"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 12-year-old boy is brought to the emergency department by his mother because he has been having difficulty breathing. He started having symptoms about 3 days ago when he started experiencing persistent coughing, runny nose, and a low grade fever. Since then he has been experiencing dyspnea that grew worse until he felt that he could no longer breathe. His mom says that this has happened many times before. On presentation, physical exam reveals an anxious, thin boy who is using his accessory muscles to breathe. Prolonged expiratory wheezes are heard on auscultation of his lungs bilaterally. During stabilization, he is prescribed a drug for treatment of his condition. The patient's mother recognizes the drug since her father, a 40-pack-year smoker, also takes the medication and she is told that the drug is able to beneficially inhibit a receptor on smooth muscle in both cases. Which of the following drugs most likely has a similar mechanism of action as the drug prescribed to this patient?", "answer": "Glycopyrrolate", "options": {"A": "Cortisol", "B": "Glycopyrrolate", "C": "Isoproterenol", "D": "Theophylline", "E": "Zileuton"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 35-year-old taxi driver presents to his physician with complaints of itchy, watery eyes and excessive sneezing that have become more severe with the change of the seasons. He has previously taken an over-the-counter medication in the past with moderate relief of his symptoms, but it made him very drowsy. He asks to switch to a medication that will not cause drowsiness that may impair his driving. Which of the following medications would you prescribe for this patient?", "answer": "Cetirizine", "options": {"A": "Cetirizine", "B": "Chlorpheniramine", "C": "Diphenhydramine", "D": "Hydroxyzine", "E": "Promethazine"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 19-year-old female college student comes to the physician for a sudden loss of visual acuity of her right eye. She noticed that she was unable to read the time on the alarm clock when she woke up in the morning. When she closes her right eye, she is able to see sharply. When she closes her left eye, she has blurry double vision. She does not recall trauma to her eye but has been working long nights on her honors thesis. She has a history of occasional shoulder luxation. She is 180 cm (5 ft 11 in) tall, and weighs 62 kg (136 lbs); her BMI is 19.1 kg/m2. Her vital signs are within normal limits. On physical examination, slender and long fingers are noted. She has several flat, demarcated brownish nevi on her left cheek. Ocular examination shows upward temporal subluxation of her right lens. Which of the following is the most likely diagnosis in this patient?", "answer": "Marfan syndrome", "options": {"A": "Joint hypermobility syndrome", "B": "Multiple endocrine neoplasia 2B", "C": "Sturge-Weber syndrome", "D": "Ehlers-Danlos syndrome", "E": "Marfan syndrome"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 62-year-old man presents to his primary care provider complaining of abdominal pain. He reports a 6-month history of gradually progressive epigastric pain and 10 pounds of unexpected weight loss. He has also noticed that his skin feels itchier than usual. His past medical history is notable for gout, hypertension, and diabetes mellitus. He takes allopurinol, enalapril, and glyburide. He has a 10-pack-year smoking history and a distant history of cocaine abuse. His temperature is 100.1°F (37.8°C), blood pressure is 135/85 mmHg, pulse is 100/min, and respirations are 20/min. On exam, he has notable hepatomegaly and a palpable gallbladder. A right upper quadrant ultrasound reveals an irregular extrahepatic mass originating from the gallbladder wall. Which of the following serum markers is most likely elevated in this patient?", "answer": "CA 19-9", "options": {"A": "Bombesin", "B": "CA-125", "C": "CA 19-9", "D": "S-100", "E": "Tartrate-resistant acid phosphatase"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 4-year-old girl from a recently immigrated family presents to the emergency department with episodes of severe coughing lasting up to several minutes followed by vomiting. She had a low grade fever and runny nose over the last 2 weeks but these coughing episodes just began one day prior to presentation. A complete blood count shows a lymphocytic infiltrate and Gram stain reveals a gram-negative coccobacillus. The emergency department physician explains that this organism causes disease by toxin-mediated inactivation of an inhibitory signaling molecule. Which of the following could be used to culture the most likely cause of this disorder?", "answer": "Regan-Lowe medium", "options": {"A": "Charcoal yeast with iron and cysteine", "B": "Eaton agar", "C": "Loffler medium", "D": "Regan-Lowe medium", "E": "Thayer-Martin agar"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 28-year-old man presents with episodic abdominal pain and bloody diarrhea for the past week. He says that the abdominal pain is diffusely localized to the periumbilical region and is dull and cramping in character. He also reports episodes of painful, bloody diarrhea up to 7 times per day. A colonoscopy is performed and shows continuous erythema, superficial ulcers, and pseudopolyps in the rectum and sigmoid colon. A biopsy is taken and sent for histological evaluation. One of the slides from the biopsy is shown in the image below. Which of the following histopathologic findings characteristic of this patient’s most likely diagnosis is marked by the yellow circle?", "answer": "Crypt abscess", "options": {"A": "Goblet cell hyperplasia", "B": "Paneth cells metaplasia", "C": "Crypt abscess", "D": "Enterocyte dysplasia", "E": "Granuloma"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 14-year-old boy is brought to the emergency department because of a 2-day history of fatigue. He reports that during this time he has had occasional palpitations and shortness of breath. He has sickle cell disease. Current medications include hydroxyurea and folic acid. He appears fatigued. His temperature is 38.3°C (100.9°F), pulse is 120/min, respirations are 24/min, and blood pressure is 112/74 mm Hg. Examination shows pale conjunctivae. Cardiac examination shows a midsystolic ejection murmur. Laboratory studies show:\nHemoglobin 6.4 g/dl\nLeukocyte count 6,000/mm3\nPlatelet count 168,000/mm3\nMean corpuscular volume 84 μm3\nReticulocyte count 0.1%\nWhich of the following is the most likely underlying cause of these findings?\"", "answer": "Parvovirus B19", "options": {"A": "Parvovirus B19", "B": "Medication-induced hemolysis", "C": "Defect in erythrocyte membrane proteins", "D": "Splenic vaso-occlusion", "E": "Hemolytic crisis"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 44-year-old woman comes to the office because of 4 episodes of loss of consciousness over the past 2 weeks. She recovered immediately and was not confused following the episodes. For the past 6 months, she has also had increased shortness of breath, palpitations, and chest tightness that resolves with rest. She immigrated with her family from India 10 years ago. Pulse is 115/min and irregular and blood pressure is 108/70 mm Hg. Cardiac examination shows an accentuated and split S2. There is an opening snap followed by a low-pitched diastolic murmur in the fifth left intercostal space at the midclavicular line. An ECG shows atrial fibrillation and right axis deviation. Which of the following is the most likely underlying mechanism of these findings?", "answer": "Increased pulmonary capillary wedge pressure", "options": {"A": "Increased pulmonary capillary wedge pressure", "B": "Increased central venous pressure", "C": "Increased oxygenated blood in the right ventricle", "D": "Increased mean arterial pressure", "E": "Increased left ventricular end diastolic pressure"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 43-year-old woman is brought to the emergency department because of severe central chest pain, mild shortness of breath, and one episode of coughing up blood since waking up that morning. The pain worsens on inspiration, and she describes it as 8 out of 10 in intensity. Three months ago, she underwent a left modified radical mastectomy for invasive ductal carcinoma. Her temperature is 37.8°C (100°F), pulse is 103/min, respirations are 20/min, and blood pressure is 102/74 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 93%. The lungs are clear to auscultation. Cardiac examination shows no abnormalities. The left lower extremity is swollen and erythematous. Laboratory studies show a normal complete blood count, creatinine of 1.0 mg/dL, and a creatinine clearance of 81 mL/min (N = 75–115). Arterial blood gas analysis on room air shows:\npH 7.49\nPCO2 29 mm Hg\nPO2 69 mm Hg\nHCO3- 22 mEq/L\nAn x-ray of the chest shows no abnormalities. Which of the following is the most appropriate next step in management?\"", "answer": "Low molecular weight heparin therapy", "options": {"A": "CT pulmonary angiography", "B": "D-dimer levels", "C": "Catheter embolectomy", "D": "Alteplase therapy", "E": "Low molecular weight heparin therapy"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 58-year-old Caucasian male with a history of peripheral vascular disease is admitted to the hospital with a painful, pulseless foot. He is prescribed antiplatelet and anticoagulant drugs. Which of the following matches a drug with its correct characteristic?", "answer": "Heparin: activates antithrombin 3", "options": {"A": "Warfarin: directly inhibits thrombin", "B": "Heparin: activates antithrombin 3", "C": "Aspirin: reversibly inhibits COX-1", "D": "Clopidogrel: antagonizes ADP receptors on endothelial cells", "E": "Prasugrel: reduced risk of bleeding compared to other drugs in its class"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 64-year-old woman comes to the physician because of several episodes of dizziness during the last month. The episodes last between 30–40 seconds and during the episodes she feels as though she is spinning. Episodes usually occur immediately after lying down or suddenly sitting up from a reclined position. They also sometimes happen when she suddenly turns her head to look at something. She has no nausea. Last month, she had an upper respiratory tract infection that resolved spontaneously. She has hypertension treated with hydrochlorothiazide. Otoscopic examination shows no abnormalities. There is no lateralization when a vibrating 512 Hz tuning fork is placed in the middle of the forehead. Which of the following is the most likely diagnosis?", "answer": "Benign paroxysmal positional vertigo", "options": {"A": "Benign paroxysmal positional vertigo", "B": "Persistent postural-perceptual dizziness", "C": "Meniere disease", "D": "Acoustic neuroma", "E": "Vestibular neuritis"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 31-year-old woman presents to her primary care physician because she has been experiencing diarrhea over the last several days. She returned from a cruise ship vacation 3 days ago and has recently been to many countries in Central and South America. After returning, she developed bloody diarrhea, nausea, and right-upper quadrant abdominal pain. Stool examination shows blood and neutrophils and imaging reveals abscesses in the liver. Which of the following findings would most likely be seen in this patient?", "answer": "Ulcers that are flask-shaped", "options": {"A": "Acid fast cysts", "B": "Motile bacteria", "C": "Non-invasive trophozoites", "D": "Non-motile bacteria", "E": "Ulcers that are flask-shaped"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 35-year-old woman that is currently being treated for chronic hepatitis C comes to the physician because of progressive fatigue for 10 days. Examination shows pale conjunctivae. Her hemoglobin concentration is 10.1 g/dL, serum total bilirubin concentration is 1.9 mg/dL, and LDH is 259 U/L (N = 45–90 U/L). Which of the following mechanisms most likely contributes to the efficacy of this patient's pharmacotherapy?", "answer": "Decreased GMP synthesis", "options": {"A": "Activation of leukocytes", "B": "Decreased release of progeny virus", "C": "Inhibition of reverse transcriptase", "D": "Inhibition of RNA polymerase", "E": "Decreased GMP synthesis"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 7-year-old boy is brought to a pediatrician by his parents. The parents say that the patient accidentally instilled a drop from a bottle of medicated eye drops into his right eye. According to them, the patient’s grandfather uses the eye drops which were prescribed for him by an ophthalmologist. The parents have brought the eye drops with them. The pediatrician notes that the eye drops contain an α1 adrenergic agonist drug. He examines the patient’s eye and finds that the eye drops have produced their expected effects. He reassures the parents about the self-limited effect of the drug and the absence of any risk of long-term complications. Which of the following effects are most likely to have occurred in this child’s eye from these eye drops?", "answer": "Contraction of the pupillary dilator muscle with no effect on the ciliary muscle", "options": {"A": "Relaxation of the pupillary sphincter muscle with no effect on the ciliary muscle", "B": "Contraction of the pupillary dilator muscle with no effect on the ciliary muscle", "C": "Relaxation of the pupillary dilator muscle with no effect on the ciliary muscle", "D": "Relaxation of the pupillary sphincter muscle with contraction of the ciliary muscle", "E": "Contraction of the pupillary dilator muscle with contraction of the ciliary muscle"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 21-year-old female comes to the physician’s office because of insomnia. For the past 9 months, the patient has been having a hard time falling asleep because she “can’t turn her mind off.” She is a student in a nearby university and spends hours at the end of each day worrying about her classes as well as her upcoming tests. When she doesn’t have tests, she worries about her family and her boyfriend even though admits she has no specific concerns about them. This constant worrying has led to insomnia and an inability to focus in class. She has also been fatigued and hasn’t had the energy to go the gym as she usually does. The most effective medication for her disorder has what mechanism of action?", "answer": "Inhibit reuptake of serotonin", "options": {"A": "Stimulates serotonin receptors", "B": "Inhibit reuptake of serotonin", "C": "Inhibition of monoamine oxidase", "D": "Increase norepinephrine and dopamine", "E": "Block dopamine receptors"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 7-year-old girl is brought to the physician because of a slightly itchy rash that first appeared 3 days ago. Her mother says she has also been complaining of headaches and achy muscles since yesterday evening. The girl went on a camping trip for school 10 days ago. She recalls being bitten several times by mosquitoes. She has a history of atopic dermatitis. She lives in Massachusetts with both parents and her 4-year-old sister. Her temperature is 39°C (102.2°F). Physical examination shows a 3-cm, nontender rash on her left upper torso. A photograph of the rash is shown. There are also multiple 5 to 8-mm erythematous papules over the lower legs and forearms. Which of the following is the most appropriate pharmacotherapy?", "answer": "Amoxicillin", "options": {"A": "Amoxicillin", "B": "Ceftriaxone", "C": "Clotrimazole", "D": "Penicillin G", "E": "Azithromycin"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 45-year-old man presents to the clinic for the third time in the past 3 weeks asking for an MRI of his lower back. He had initially gone to the gym as advised by his wife and had started doing some back exercises. The next day, he developed soreness in his lower back and spent the whole day online trying to figure out what was wrong with him. He has been to the emergency department a few times and subsequently has been redirected to the clinic where each time he was thoroughly examined and investigated for all the possible causes. The patient still exhibits worry and would like to get an MRI to make sure everything is ‘okay.’ Which of the following is the most likely diagnosis in this patient?", "answer": "Illness anxiety disorder", "options": {"A": "Illness anxiety disorder", "B": "Delusional disorder", "C": "Somatic symptom disorder", "D": "Factitious disorder", "E": "Munchausen syndrome"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 25-year-old woman presents to the urgent care clinic for cough for the past five days. She recently moved to the area and has not yet established a primary care doctor. She has noticed worsening runny nose with congestion, sneezing, and tearing over the past few days. She initially thought that it was just due to dust from moving boxes into her new apartment, but her symptoms did not improve after cleaning her belongings and vacuuming her floor. She feels some relief after splashing her face with cold water, but her symptoms recur within ten minutes. She has no pets and does not take any medications. Her physical exam reveals examples of findings shown in Figures A-C. No rales or wheezes are appreciated on lung auscultation, but bronchial breath sounds are heard at the bases. The patient states that she will need to drive back home after this visit. What is the best initial step in management?", "answer": "Intranasal corticosteroids", "options": {"A": "Oral loratadine", "B": "Intranasal corticosteroids", "C": "Intravenous diphenhydramine", "D": "Sublingual oseltamivir", "E": "Oral montelukast"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 73-year-old woman with atrial fibrillation presents to your clinic to discuss the need for anticoagulation. Her PMH is significant for high blood pressure, diabetes mellitus type II, osteoporosis, and depression. She previously smoked but quit about 16 years ago. She has never had a stroke or TIA. Her physical examination is remarkable for an irregular heart rate. She has a blood pressure of 136/94 mm Hg and a heart rate of 74/min. What is her CHADS2 score?", "answer": "2", "options": {"A": "1", "B": "2", "C": "3", "D": "4", "E": "Too little information to tell"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 26-year-old woman is admitted to the hospital because of a 3-day history of tingling and weakness in the lower extremities. Neurologic examination shows areflexia of the ankle and knee joints bilaterally. Motor strength is 1/5 in both lower legs. Over the next 3 weeks, the patient's condition progresses to involve both upper extremities, and she requires ventilatory support. Six weeks after admission, deep tendon reflexes are 1+ in the ankles, and she is able to wiggle her toes. Which of the following is most likely responsible for the improvement in this patient's neurological status?", "answer": "Remyelination of peripheral nerves", "options": {"A": "Synthesis of monoamine neurotransmitters", "B": "Remyelination of peripheral nerves", "C": "Replication of oligodendrocyte precursor cells", "D": "Accumulation of S-adenosylmethionine", "E": "Lymphocytic infiltration in the endoneurium\n\""}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 42-year-old woman presents to her primary care physician for fatigue and blurry vision. She is a refugee from Syria who arrived in the United States 1 week ago. She has lived for the last 8 months in a refugee camp. She worked at a grocery store in Syria before being displaced from her home. She has one son who is 9 years old and was seen by a pediatrician the day prior. She reports that while she was in the refugee camp, she ate very little and gave most of her food to her son to ensure that he stayed healthy. She denies any past medical history and takes no medications. She does not smoke or drink alcohol. Her temperature is 97.8°F (36.6°C), blood pressure is 108/68 mmHg, pulse is 102/min, and respirations are 18/min. On exam, she appears fatigued but is fully cooperative with the examination. There are fissures at the corners of her mouth. A funduscopic examination reveals corneal vascularization in both eyes. Her tongue is darkly erythematous. This patient is most likely deficient in a vitamin that has which of the following functions?", "answer": "Precursor to FAD and FMN", "options": {"A": "Cofactor for homocysteine methyltransferase", "B": "Cofactor for pyruvate dehydrogenase enzyme", "C": "Precursor to FAD and FMN", "D": "Constituent of NAD+ and NADP+", "E": "Component of coenzyme A"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 70-year-old man was first evaluated for an enlarging neck mass with complaints of night sweats, fever, and weight loss. Excisional biopsy confirms the diagnosis of Burkitt lymphoma. The patient is started on a CODOX-M/IVAC chemotherapy regime. The physician notes a marked improvement, but is concerned about a common complication of chemotherapy. The patient is prescribed rasburicase in response to this complication. Which of the following statements describing the patient’s current state is most accurate?", "answer": "Rasburicase converts uric acid to allantoin, increasing its secretion", "options": {"A": "Rasburicase is a xanthine oxidase inhibitor", "B": "The development of hyperuricemia is gradual", "C": "This complication only occurs in response to radiation", "D": "Rasburicase converts uric acid to allantoin, increasing its secretion", "E": "Hypophosphatemia is expected to develop in this patient"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A previously healthy 41-year-old man is brought to the emergency department 30 minutes after collapsing at home. Cardiopulmonary resuscitation is attempted for 10 minutes without success. A photograph of sections of the heart obtained at autopsy is shown. The patient's condition is most likely associated with which of the following pathophysiologic changes?", "answer": "Marked noncompliance of the left ventricular wall", "options": {"A": "Retrograde blood flow from the aorta into the left ventricle", "B": "Significantly reduced myocardial contraction force", "C": "Fixed obstruction of the left ventricular outflow tract", "D": "Marked noncompliance of the left ventricular wall", "E": "Severe narrowing of the left anterior descending artery"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 68-year-old woman comes to the physician with increasing fatigue and shortness of breath for 2 weeks. She has only passed very small amounts of urine over the past few days. During this time, she has also noticed that her feet appear unusually puffy for a few hours every morning. Three weeks ago, she had a sore throat that resolved spontaneously after several days without antibiotic therapy. She has a 6-month history of lower back and thoracic pain, for which she takes ibuprofen daily. Her only other medication is a laxative for constipation, which she first experienced 8 months ago. Her sister has systemic lupus erythematosus. Her temperature is 37.9°C (98.9°F), pulse is 110/min, respirations are 22/min, and blood pressure is 150/100 mm Hg. Examination shows pedal edema and conjunctival pallor. There is tenderness to palpation over the lumbar spine and the 8th rib on the right. Cardiac examination shows no abnormalities. Laboratory studies show:\nHemoglobin 9.8 mg/dL\nSerum\nUrea nitrogen 50 mg/dL\nCreatinine 2.8 mg/dL\nCalcium 12.9 mg/dL\nUrine\nProtein negative\nBlood negative\nWhich of the following is the most likely underlying cause of this patient's symptoms?\"", "answer": "Immunoglobulin light chains", "options": {"A": "Antiglomerular basement membrane antibodies", "B": "Renal deposition of AL amyloid", "C": "Immunoglobulin light chains", "D": "Decreased cardiac ejection fraction", "E": "Anti-streptococcal antibodies"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 13-month-old male needs to have surgery for an undescended testicle. The child lives with his 16-year-old mother only. His 19-year-old father is not involved. From whom should the surgeon get consent for the procedure?", "answer": "The mother", "options": {"A": "The mother", "B": "The father", "C": "A grandparent", "D": "The hospital's medical ethics committee", "E": "A judge"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 7-year-old boy is brought to the emergency department after he was bitten by a dog. The patient was at a friend's house, and he was bitten when he pulled the dog's tail while it was eating. The patient is currently doing well and has a dog bite on his right distal forearm. His temperature is 98.2°F (36.8°C), blood pressure is 100/60 mmHg, pulse is 123/min, respirations are 19/min, and oxygen saturation is 98% on room air. The wound is thoroughly irrigated in the emergency department. Which of the following is the best next step in management?", "answer": "Quarantine and observe the animal", "options": {"A": "Ciprofloxacin and metronidazole", "B": "Closure of the wound via sutures", "C": "Euthanasia of the animal", "D": "Quarantine and observe the animal", "E": "Rabies vaccine and rabies immunoglobulin"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 35-year-old woman, otherwise healthy, presents with frequent nosebleeds and bruising on her legs. She says that her symptoms started about 6 months ago and have not improved. She remembers that her 8-year-old son had similar symptoms about a month ago following a viral respiratory infection, but his symptoms quickly resolved without treatment. No significant past medical history and no current medications. Family history is significant for her father dying at age 65 of myocardial infarction. Review of systems is significant for her last period 2 weeks ago being a bit heavier than usual. Her vital signs include: temperature 37.0°C (98.6°F), blood pressure 100/75 mm Hg, pulse 98/min, respirations 15/min, and oxygen saturation 99% on room air. On physical examination, the patient is alert and cooperative. Cardiac exam is normal. Lungs are clear to auscultation. There is non-palpable purpura present on the lower extremities bilaterally. Which of the following set of laboratory results and peripheral blood smear findings would most likely be seen in this patient?", "answer": "Platelets: Decreased | Bleeding time: Increased | PT: Normal| PTT: Normal| Blood smear: Schistocytes absent", "options": {"A": "Platelets: Decreased | Bleeding time: Increased | PT: Normal | PTT: Normal | Blood smear: Schistocytes present", "B": "Platelets: Decreased | Bleeding time: Increased | PT: Increased| PTT: Increased | Blood smear: Schistocytes present", "C": "Platelets: Increased | Bleeding time: Decreased| PT: Normal| PTT: Normal | Blood smear: Schistocytes absent", "D": "Platelets: Decreased | Bleeding time: Increased | PT: Decreased| PTT: Normal| Blood smear: Schistocytes present", "E": "Platelets: Decreased | Bleeding time: Increased | PT: Normal| PTT: Normal| Blood smear: Schistocytes absent"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 65-year-old woman comes to the physician because of urinary straining and delayed flow of urine for 1 month. She has a medical history significant for long-standing asthma. Recently, she has been taking albuterol more frequently on an as-needed basis. She was diagnosed with major depression last year. Currently, her symptoms of depression are under control. Her medications include inhaled salmeterol and fluticasone propionate and oral amitriptyline, the dose of which was increased recently due to uncontrolled depressive symptoms. The vital signs include: temperature 37.1°C (99.8°F), pulse rate 80/min, respiratory rate 14/min, and blood pressure 110/70 mm Hg. On examination, she has dry oral mucous membranes. The remainder of the examination shows no abnormalities. Which of the following is the most appropriate modification in this patient’s drug therapy?", "answer": "Switching amitriptyline to fluoxetine", "options": {"A": "Adding ipratropium bromide inhaler", "B": "Adding oral oxybutynin", "C": "Reducing the dose of albuterol", "D": "Switching amitriptyline to fluoxetine", "E": "No change is required at this time"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "An 8-year-old girl is brought by her mother to her pediatrician’s office for a follow-up visit. She was diagnosed with asthma about 4 years ago and has been on medications ever since. She came into the doctor’s office about a month ago with an escalation of her symptoms. She told her doctor that she has been struggling to breathe almost every single day. This difficulty increased when she played outdoors with her friends. She said that she used to wake up at least 3 times a week from sleep to use her inhaler. She uses a short-acting β-agonist inhaler to control her symptoms. At the previous visit, her doctor had started her on a small dose of fluticasone (inhaled) as well as a long-acting β-agonist inhaler. She has some improvement in her symptoms. On physical examination, she doesn’t seem to be in distress, and currently, the lungs are clear on auscultation. Her forced expiratory volume in one second is about 70% of the predicted value. Based on the description of these patients symptoms and current treatment regime, which of the following categories describes the severity of this child’s symptoms?", "answer": "Moderate persistent", "options": {"A": "Status asthmaticus", "B": "Mild intermittent", "C": "Mild persistent", "D": "Moderate persistent", "E": "Severe persistent"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "An 18-year-old woman presents with recurrent headaches. The pain is usually unilateral, pulsatile in character, exacerbated by light and noise, and usually lasts for a few hours to a full day. The pain is sometimes triggered by eating chocolates. These headaches disturb her daily routine activities. The physical examination was within normal limits. She also has essential tremors. Which drug is suitable in her case for the prevention of headaches?", "answer": "Propranolol", "options": {"A": "Ergotamine", "B": "Verapamil", "C": "Valproic", "D": "Sumatriptan", "E": "Propranolol"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 26-year-old man is brought to the emergency department by the police after threatening to harm his roommate earlier today. He reports that someone on the radio told him to do so. His family reports that, during the past two years, the patient has become increasingly more withdrawn from family and friends. He states that he has spent the majority of the last year alone in his room “working on a project at home to save the earth from an evil alien power.” There is no family history of serious illness. He has smoked marijuana on a daily basis since he was thirteen. Vital signs are within normal limits. On mental status examination, he has a flat affect and his speech is disorganized. An MRI scan of the head is most likely to show which of the following?", "answer": "Enlarged cerebral ventricles", "options": {"A": "Periventricular plaques and white matter lesions", "B": "Nucleus caudatus atrophy", "C": "Ring-enhancing lesion", "D": "Hyperintense temporal lobe lesion", "E": "Enlarged cerebral ventricles"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 46-year-old anesthesiologist is found placing several syringes of amobarbital in his backpack prior to leaving the hospital. When confronted, the anesthesiologist admits that he began abusing the medication the previous year, after his divorce was finalized. He has been using it on a daily basis since then, and his most recent usage was 8 hours ago. Which of the following is the most life-threatening complication of amobarbital withdrawal?", "answer": "Cardiovascular collapse", "options": {"A": "Internal bleeding", "B": "Respiratory depression", "C": "Hypothermia", "D": "Cardiovascular collapse", "E": "Self-inflicted violence"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 55-year-old man is brought to the emergency department for 1 episode of bloody emesis. He reports feeling lightheaded this morning and shortly after breakfast, he felt nauseous and had an episode of bloody emesis. He denies any trauma, fever, abnormal ingestions, or recent infections. He endorses black stools over the past few days. His past medical history is significant for alcohol abuse and cirrhosis. A physical examination demonstrates mild jaundice and ascites. What is the mechanism of action of the medication that can be used in the management of this patient’s condition?", "answer": "Somatostatin analog leading to constriction of the splanchnic vessels", "options": {"A": "Antagonists of ß1 and ß2 adrenergic receptors", "B": "Inhibition of gastric parietal cell H+/K+ ATPase", "C": "Reversible block of histamine H2 receptors", "D": "Somatostatin analog leading to constriction of the splanchnic vessels", "E": "Stimulation of cGMP production leading to vascular smooth muscle relaxation"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "Shortly after undergoing a bipolar prosthesis for a displaced femoral neck fracture of the left hip acquired after a fall the day before, an 80-year-old woman suddenly develops dyspnea. The surgery under general anesthesia with sevoflurane was uneventful, lasting 98 minutes, during which the patient maintained oxygen saturation readings of 96–100% on 8 L of oxygen. She has a history of hypertension, osteoporosis, and osteoarthritis of her right knee. Her medications include ramipril, naproxen, ranitidine, and a multivitamin. She appears cyanotic, drowsy, and is oriented only to person. Her temperature is 38.6°C (101.5°F), pulse is 135/minute, respirations are 36/min, and blood pressure is 155/95 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 81%. There are several scattered petechiae on the anterior chest wall. Laboratory studies show a hemoglobin concentration of 10.5 g/dL, a leukocyte count of 9,000/mm3, a platelet count of 145,000/mm3, and a creatine kinase of 190 U/L. An ECG shows sinus tachycardia. Which of the following is the most likely diagnosis?", "answer": "Fat embolism", "options": {"A": "Traumatic rhabdomyolysis", "B": "Fat embolism", "C": "Thyrotoxic crisis", "D": "Malignant hyperthermia", "E": "Meningitis\n\""}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 34-year-old woman presents to her primary care physician complaining of weakness and rash for the past 2 months. She says her symptoms had a gradual onset at first, but over the past 2 weeks she has grown more concerned as she now has difficulty going up and down the stairs in her apartment. Her rash is nonpruritic and confined to her knuckles. She denies fever, chills, and changes in bowel habits, cough, or shortness of breath. Up until the onset of her symptoms she had been an avid hiker in upstate New York. Temperature is 98.0°F (36.7°C) blood pressure is 110/72 mmHg, pulse is 88/min, and respirations are 20/min. Physical examination demonstrates 4-/5 strength in the proximal lower extremities. The patient's cutaneous findings are demonstrated in figure A. Laboratory studies will most likely demonstrate the following in this patient?", "answer": "Anti-histidyl tRNA synthetase antibodies", "options": {"A": "Anti-endomysial antibodies", "B": "Anti-histidyl tRNA synthetase antibodies", "C": "Anti-histone antibodies", "D": "Anti-HMG CoA reductase antibodies", "E": "Anti-mitochondrial antibodies"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 4-day-old, full-term infant born by uncomplicated vaginal delivery is brought to a pediatrician by his mother, who notes that her son's skin appears yellow. She reports that the child cries several times per day, but sleeps 7-8 hours at night, uninterrupted. She has been breastfeeding exclusively and feels that he has been feeding well. He has been having a bowel movement on average once every 3 days. Which of the following is the most likely etiology of the patient's presentation?", "answer": "Breastfeeding jaundice", "options": {"A": "Breastfeeding jaundice", "B": "Breast milk jaundice", "C": "Glucose-6-phosphate dehydrogenase deficiency", "D": "Crigler-Najjar syndrome", "E": "Hepatitis A"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 23-year-old female comes to the office because of a 3-week history of vaginal discharge and itching despite cleaning her genitals with a vaginal douche. Her last menstrual period was one week ago. She is sexually active with her new boyfriend. She has an intrauterine device and does not use barrier protection. She was treated for a sore throat infection one month ago. Speculum examination shows erythema around the vaginal introitus and copious white discharge. Vaginal pH is 4.3 and a KOH test shows multiple pseudohyphae on microscopy. Which of the following is the strongest predisposing factor for this patient's condition?", "answer": "Suppression of vaginal bacterial flora", "options": {"A": "Intrauterine pregnancy", "B": "Suppression of vaginal bacterial flora", "C": "Increased vaginal pH", "D": "Intrauterine device", "E": "Unprotected sexual intercourse"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 3-year-old boy who has no known past medical or family history is brought by his parents to his pediatrician for new symptoms. Specifically, his parents state that he has suffered from a fever associated with diarrhea and conjunctivitis over the past week or so. His parents note that he has never had an episode of diarrhea like this previously, but that several other children at his daycare had been ill recently. The blood pressure is 112/70 mm Hg, heart rate is 94/min, respiratory rate is 14/min, and temperature is 37.0°C (98.6°F). The physical exam is significant for preauricular adenopathy. Which of the following interventions would have been most effective to prevent this condition?", "answer": "Better hand-washing practices", "options": {"A": "Appropriate immunization", "B": "Giving antibiotics", "C": "Better hand-washing practices", "D": "Keeping all food stored in the refrigerator", "E": "Avoiding undercooked seafood"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 24-year-old woman with no past medical history presents to her PCP for a routine checkup. She feels generally healthy but has noticed a new vaginal discharge that has a strange odor. The patient has been in a long-term relationship and denies any new sexual partners. She denies vaginal itching, abnormal menstruation, or dyspareunia. Vital signs are within normal limits. The physical exam reveals thin, greyish-white vaginal discharge but is otherwise unremarkable. A sample of this discharge is collected. What would be the most likely finding on wet mount?", "answer": "Epithelial cells with stippling", "options": {"A": "Blue-green pigmented bacteria", "B": "Motile, flagellated protozoans", "C": "Long, branching filamentous structures", "D": "Epithelial cells with stippling", "E": "Large mucoid capsules"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 50-year-old African-American woman comes to the physician because of right elbow pain for the past 12 hours. The pain is currently at 7 out of 10 in intensity. She has not had any trauma to the right elbow. She also reports general malaise. She had a miscarriage at the age of 37 years. One year ago, she had carpal tunnel syndrome that was treated with a volar splint. Three months ago, she was diagnosed with thrombophlebitis, which responded well to treatment with ibuprofen and compression therapy. She runs 5 km (3.1 miles) per week. She works as an accountant. She drinks 1–2 glasses of wine on weekends. She is 171 cm (5 ft 7 in) tall and weighs 70 kg (154 lbs); BMI is 23.9 kg/m2. Her pulse is 110/min, blood pressure is 130/80 mm Hg, and temperature is 38.3°C (101°F). On physical examination, the skin above her right elbow is erythematous and severely tender to palpation. Laboratory studies show:\nHemoglobin 13.5 g/dL\nLeukocyte count 9,520/mm3\nPlatelet count 853,000/mm3\nSerum\nNa+ 136 mEq/L\nK+ 3.7 mEq/L\nCl- 96 mEq/L\nCa2+ 11.0 mg/dL\nHCO3- 25 mEq/L\nGlucose 102 mg/dL\nCreatinine 1.0 mg/dL\nUric acid 10.5 mg/dL\nFurther evaluation of this patient is most likely to show which of the following?", "answer": "Mutation in Janus kinase 2 gene", "options": {"A": "Mutation in Janus kinase 2 gene", "B": "Howell-Jolly bodies", "C": "Antibodies against citrullinated peptides", "D": "Calcium pyrophosphate dihydrate deposits", "E": "Anti-phospholipid antibodies"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 64-year-old man is brought to his primary care physician by his daughter for forgetfulness. The patient’s daughter reports that over the past 2 weeks the patient has become more confused. He did not remember to pick up his car from the body shop last week, and yesterday, he did not show up to his grandson’s birthday party. When she went over to the patient’s house to check on him, she noticed the mailbox was stuffed with unopened letters. The patient says “I’m fine. I just have a headache.” The patient’s daughter adds, “I just hope you’re not drinking again dad. Your neighbor saw you fall outside the house a few weeks ago, and the other day you said you were nauseous and vomited.” The patient’s medical history is significant for a history of alcohol abuse, hypertension, hyperlipidemia, and atrial fibrillation. He takes aspirin, amlodipine, metoprolol, atorvastatin, and warfarin. He smokes cigars, but denies alcohol use since he started psychotherapy 7 months ago. The patient’s temperature is 97°F (36.1°C), blood pressure is 144/92 mmHg, and pulse is 82/min. On physical examination, there is a 3 cm ecchymosis on the right scalp. No focal neurological deficits are appreciated. Gait is normal. An initial complete blood count shows normocytic anemia. The patient’s INR is 2.5. Imaging is pending. Which of the following is a treatment option for the patient’s most likely diagnosis?", "answer": "Burr hole", "options": {"A": "Alteplase", "B": "Burr hole", "C": "Donepezil", "D": "Thiamine supplementation", "E": "Vitamin B12 supplementation"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 60-year-old man presents to the physician for a follow-up examination. During the previous visit, splenomegaly was detected on the abdominal exam, which has been confirmed by abdominal ultrasound. He has no complaints other than fatigue for several months. There is no history of serious illness. His only medication is acetaminophen for knee pain. The temperature is 36.7℃ (98.1℉), pulse is 68, respirations are 12/min, and blood pressure is 125/70 mm Hg. On physical examination, the spleen size on percussion is 16 cm (6.2 in). Otherwise, the physical examination shows no abnormalities. The laboratory test results are as follows:\nHemoglobin 10 g/dL\nMean corpuscular volume 90 μm3\nLeukocyte count 80,000/mm3\nPlatelet count 450,000/mm3\nThe peripheral blood smear shows a predominance of neutrophils and the presence of band cells, myelocytes, promyelocytes, and blasts (< 5%). The cytogenetic study shows t(9;22). Which of the following is the most likely diagnosis?", "answer": "Chronic myeloid leukemia", "options": {"A": "Acute lymphoid leukemia", "B": "Chronic myeloid leukemia", "C": "Classical Hodgkin’s lymphoma", "D": "Hairy cell leukemia", "E": "Burkitt lymphoma"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 55-year-old man comes to the physician because of balance problems. He follows a vegan diet and does not eat meat, eggs, or dairy. Physical examination shows pale oral mucosa and conjunctivae. Neurologic examination shows normal strength in all extremities and decreased sense to vibration in his lower extremities bilaterally. A peripheral blood smear is shown. Which of the following enzymes is most likely impaired?", "answer": "Methylmalonyl-CoA mutase", "options": {"A": "Succinate dehydrogenase", "B": "Propionyl-CoA carboxylase", "C": "Pyruvate carboxylase", "D": "Methylmalonyl-CoA mutase", "E": "Dopamine beta-hydroxylase"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 32-year-old woman presents to her primary care physician for generalized fatigue. She states that she is doing well but that she always feels tired. She started exercising to have more energy, finds that she tires easily, and has not felt motivated to return to the gym. She is doing well and is excelling at her job. She recently started a vegan diet in order to try and become healthy. She is currently struggling with dating and is unable to find a compatible mate and feels hopeless about this. The patient has a past medical history of uterine leiomyomas. Her temperature is 99.5°F (37.5°C), blood pressure is 100/68 mmHg, pulse is 80/min, respirations are 14/min, and oxygen saturation is 98% on room air. Laboratory values are ordered as seen below.\n\nHemoglobin: 10 g/dL\nHematocrit: 32%\nMCV: 78 µm^3\nFerritin: 10 mg/mL\nTotal iron binding capacity: 620 mcg/dL\nLeukocyte count: 6,500/mm^3 with normal differential\nPlatelet count: 190,000/mm^3\n\nSerum:\nNa+: 141 mEq/L\nCl-: 102 mEq/L\nK+: 4.1 mEq/L\nHCO3-: 24 mEq/L\nBUN: 20 mg/dL\nGlucose: 99 mg/dL\nCreatinine: 1.1 mg/dL\nCa2+: 10.2 mg/dL\nTSH: 4.7 mIU/mL\nAST: 12 U/L\nALT: 10 U/L\n\nWhich of the following is the next best step in management?", "answer": "Iron", "options": {"A": "Vitamin B9", "B": "Vitamin B12", "C": "Iron", "D": "Assess for depression", "E": "Order a complete iron studies panel"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 28-year-old woman, gravida 1, para 0, at 24 weeks' gestation comes to the physician for a prenatal visit. She feels well. She has no history of medical illness and takes no medications. Her fasting serum glucose is 91 mg/dL. One hour after drinking a concentrated glucose solution, her serum glucose concentration is 94 mg/dL. The hormone responsible for the observed laboratory changes most likely increases glucose transport into which of the following types of cells?", "answer": "Adipocytes", "options": {"A": "Spermatocytes", "B": "Islet cells", "C": "Adipocytes", "D": "Placental cells", "E": "Erythrocytes"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 27-year-old woman presents to the emergency department with weakness of her legs which has progressed to an inability for her to stand. The patient works as a school teacher in Alaska and regularly goes hiking and camping. She recently returned from a camping trip where she hiked through tall brush and drank from mountain streams. The patient was also involved in a motor vehicle accident 2 days ago but did not seek treatment. The patient has a medical history that is unremarkable and is currently taking multivitamins and other than a recent bout of diarrhea is generally healthy. Her temperature is 99.5°F (37.5°C), blood pressure is 120/68 mmHg, pulse is 120/min, respirations are 17/min, and oxygen saturation is 98% on room air. Physical exam is notable for a very anxious woman with 1/5 strength of the patient’s lower extremities and 2/5 strength of her trunk muscles with diminished sensation. Laboratory studies are ordered as seen below.\n\nHemoglobin: 15 g/dL\nHematocrit: 43%\nLeukocyte count: 6,500/mm^3 with normal differential\nPlatelet count: 194,000/mm^3\n\nSerum:\nNa+: 138 mEq/L\nCl-: 102 mEq/L\nK+: 4.4 mEq/L\nHCO3-: 24 mEq/L\nBUN: 20 mg/dL\nGlucose: 120 mg/dL\nCreatinine: 1.0 mg/dL\nCa2+: 10.2 mg/dL\npH: 7.44\nPaCO2: 10 mmHg\nPaO2: 90 mmHg\nAST: 12 U/L\nALT: 10 U/L\n\nThe patient complains about difficulty breathing. Repeat laboratory values are notable for the findings below.\n\npH: 7.35\nPaCO2: 30 mmHg\nPaO2: 80 mmHg\n\nThe patient is intubated and sent to the MICU. Which of the following risk factors is associated with the most likely diagnosis?", "answer": "Consuming meats cooked over a campfire", "options": {"A": "Female sex living in a Northern latitude", "B": "Hiking in tick-infested woods", "C": "Consuming meats cooked over a campfire", "D": "Pelvic trauma", "E": "Central cervical spine trauma"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "An 18-year-old male presents to the emergency room smelling quite heavily of alcohol and is unconscious. A blood test reveals severe hypoglycemic and ketoacidemia. A previous medical history states that he does not have diabetes. The metabolism of ethanol in this patient's hepatocytes resulted in an increase of the [NADH]/[NAD+] ratio. Which of the following reaction is favored under this condition?", "answer": "Oxaloacetate to malate", "options": {"A": "Pyruvate to acetyl-CoA", "B": "Citrate to isocitrate", "C": "Oxaloacetate to malate", "D": "Oxaloacetate to phosphoenolpyruvate", "E": "Fumarate to malate"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A previously healthy 7-year-old girl is brought to the physician for a well-child examination. She feels well. She emigrated from India 3 months ago. There is no family history of serious illness. Her immunizations are up-to-date. She is at 60th percentile for height and weight. Her temperature is 37°C (98.6°F), pulse is 90/min, and respirations are 26/min. Examination shows no abnormalities. Laboratory studies show:\nHemoglobin 13.2 g/dL\nLeukocyte count 8900/mm3\nPlatelet count 310,000/mm3\nSerum\nHepatitis B surface antigen negative\nHepatitis B antibody positive\nInterferon-γ release assay positive\nAn x-ray of the chest shows no abnormalities. Which of the following is the most appropriate next step in management?\"", "answer": "Administer isoniazid", "options": {"A": "Perform acid-fast stain on induced sputum", "B": "Administer isoniazid", "C": "Reassurance and follow up", "D": "Perform tuberculin skin test", "E": "Administer isoniazid, rifampin, ethambutol and pyrazinamide"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "Please refer to the summary above to answer this question\nAn 8-year-old boy is brought to the physician by his mother for a well-child examination at a clinic for low-income residents. Although her son's elementary school offers free afterschool programming, her son has not been interested in attending. Both the son's maternal and paternal grandmothers have major depressive disorder. The mother is curious about the benefits of afterschool programming and asks for the physician's input. Based on the study results, which of the following statements best addresses the mother's question?\"", "answer": "High-quality afterschool programming for low-income 8-year-olds may correlate with decreased ADHD risk in adults.\n\"", "options": {"A": "The patient's family history of psychiatric illness prevents any conclusions from being drawn from the study.", "B": "High-quality afterschool programming for low-income 8-year-olds may correlate with decreased bipolar disorder risk in adults.", "C": "High-quality afterschool programming would decrease this patient's risk of developing major depressive disorder.", "D": "High-quality afterschool programming should be free of charge for low-income children to improve adult mental health.", "E": "High-quality afterschool programming for low-income 8-year-olds may correlate with decreased ADHD risk in adults.\n\""}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "Two days after delivery, a 2450-g (5-lb 6-oz) male newborn has three episodes of green vomitus. He has passed urine twice a day, but has not yet passed stool. He was born at 34 weeks' gestation. He appears irritable. His temperature is 37.3°C (99.1°F), pulse is 161/min, respirations are 56/min, and blood pressure is 62/44 mm Hg. Examination shows a distended abdomen; there is diffuse tenderness to palpation over the abdomen. Bowel sounds are decreased. Digital rectal examination is unremarkable. The remainder of the examination shows no abnormalities. An x-ray of the abdomen shows dilated bowel loops. Contrast enema demonstrates inspissated meconium plugs in the distal ileum and microcolon. Which of the following is the child most likely to develop?", "answer": "Infertility", "options": {"A": "Type 1 diabetes mellitus", "B": "Infertility", "C": "Alzheimer's disease", "D": "Asthma", "E": "Necrotizing enterocolitis"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 6-week-old boy is brought to see his pediatrician. His mother says that he has not been feeding well and forcefully vomited after every feed over the past 4 days. The infant was born at 39 weeks gestation via spontaneous vaginal delivery. He is up to date on all vaccines and is meeting all developmental milestones. However, a week after delivery he developed a respiratory infection involving an aggressive cough followed by a high-pitched intake of breath. Respiratory cultures were positive for a gram-negative coccobacilli for which he received erythromycin. Since then he has remained healthy until now. On examination, the infant’s vitals are normal but he appears lethargic and mildly dehydrated with depressed fontanelles and decreased skin turgor. A firm non-tender mass is palpated in the epigastric region. Which of the following is most likely a cause of this baby’s symptoms?", "answer": "Antibiotic use", "options": {"A": "Deficiency of nitric oxide synthase", "B": "Antibiotic use", "C": "Inadequate myenteric plexus innervation", "D": "Telescoping of the proximal bowel into a distal segment", "E": "Incomplete endodermal proliferation of the gut"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 67-year-old man presents to his primary care physician because he has been feeling increasingly short of breath. Specifically, after retirement he has been going on daily morning walks with his wife; however, over the last year he feels that his endurance has decreased. His medical history is significant for well-controlled hypertension but is otherwise unremarkable. When asked, he reveals that he worked in a variety of industries throughout his life. Testing demonstrates decreased forced vital capacity (FVC) and a normal forced expiratory volume (FEV) to FVC ratio. Pathology demonstrates changes primarily in the upper lobes where macrophages can be seen with dark round ingested particles. Which of the following is most likely associated with the cause of this patient's symptoms?", "answer": "Lung rheumatoid nodules", "options": {"A": "Diabetes insipidus", "B": "Increased risk of lung cancer", "C": "Increased risk of tuberculosis", "D": "Mesothelioma", "E": "Lung rheumatoid nodules"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 75-year-old woman is brought to the emergency department because of vomiting, abdominal pain, and constipation for the past 2 days. She has urinated frequently over the past week and has become excessively thirsty during this time. She has no significant past medical history. She is a 30-pack-year smoker. She appears confused. Her blood pressure is 95/70 mm Hg, pulse is 110/min, respirations are 25/min, and temperature is 37.1°C (98.8°F). She has dry oral mucosa. Lung auscultation shows rhonchi and wheezing localized to the right middle lobe area. An electrocardiogram (ECG) shows a shortened QT interval. A computed tomography scan is shown. Which of the following is the most likely cause of this patient’s recent condition?", "answer": "Squamous cell carcinoma", "options": {"A": "Adenocarcinoma", "B": "Bronchoalveolar carcinoma", "C": "Large-cell carcinoma", "D": "Small-cell lung cancer", "E": "Squamous cell carcinoma"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 23-year-old woman comes to the physician because of a painless lesion on the arm that first appeared 5 days after she visited a petting zoo. The lesion began as a small papule and then became a blister that has since ulcerated. Her temperature is 38.3°C (101°F). Examination shows a black eschar with edematous borders on the left upper arm. There is axillary lymphadenopathy. The virulence factor responsible for the edema seen in this patient has a mechanism of action similar to which of the following enzymes?", "answer": "Adenylate cyclase", "options": {"A": "IgA protease", "B": "Adenylate cyclase", "C": "Catalase", "D": "Guanylate cyclase", "E": "SNARE protein"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 54-year-old man with a history of hypertension presents 6 days after being admitted for new-onset atrial fibrillation with the rapid ventricular rate with a painful lesion on his left leg. He says his heart rate has been well-controlled since starting metoprolol and warfarin in the hospital but says he has developed a painful lesion on his left leg. His blood pressure is 114/78 mm Hg, the heart rate is 84/min, and the respiratory rate is 15/min. On physical examination, there is a large, dark lesion on his left leg that feels cold (see image). A genetic defect, in which of the following proteins is most likely responsible for this patient’s condition?", "answer": "Protein C", "options": {"A": "Factor V", "B": "von Willebrand factor", "C": "Factor XII", "D": "Protein C", "E": "Factor VIII"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 35-year-old patient presents to the dermatologist with a new skin rash. The patient has noticed new bumps on her arm over the past 1 month. The bumps are about 0.5 cm in diameter and are filled with a clear fluid. They extend on both arms but are not in her mouth or torso. The lesions do not pop with pressure but remain tense. Her skin does not slough off with rubbing. The patient denies any other symptoms including joint pain or fever. The patient has no other medical history. The patient’s condition is most likely caused by antibodies against which of the following compounds?", "answer": "Hemidesmosomes", "options": {"A": "E-cadherin", "B": "Desmoglein", "C": "Hemidesmosomes", "D": "Double-stranded DNA", "E": "U1 ribonucleotide polypeptide"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 59-year-old woman presents to the emergency department because of shortness of breath. She has been experiencing an increasing inability to breathe following strenuous activity. This includes climbing stairs and walking a few blocks down the street. During the day, her breathing becomes more pronounced when she takes her a nap or lies down to sleep at night. Another concerning symptom is the increased swelling in her legs. She has a history of few episodes of syncope. Her past medical history is otherwise unremarkable. The vital signs include: blood pressure 110/70 mm Hg, pulse 90/min, and respiratory rate 18/min. An electrocardiogram (ECG) shows low voltage. Echocardiography shows granular speckling with concentric thickening of the ventricular walls, more prominently of the right wall. Which of the following confirmatory tests is most appropriate?", "answer": "Biopsy of cardiac tissue", "options": {"A": "Pulmonary function test", "B": "Biopsy of cardiac tissue", "C": "Cardiac stress test", "D": "Chest X-ray", "E": "No further testing required"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 30-year-old previously healthy male presents to your office with complaints of facial pressure and rhinorrhea for the past 3 weeks. The patient reports that several weeks prior, he had a “common cold” which resolved. However, he has since developed worsening facial pressure, especially over his cheeks and forehead. He reports over 1 week of green tinged rhinorrhea. His temperature is 100.1 deg F (37.8 deg C), blood pressure is 120/70 mmHg, pulse is 85/min, and respirations are 15/min. Nasal exam reveals edematous turbinates and purulent discharge. What is the most likely diagnosis?", "answer": "Acute bacterial rhinosinusitis", "options": {"A": "Acute viral rhinosinusitis", "B": "Acute bacterial rhinosinusitis", "C": "Subacute bacterial rhinosinusitis", "D": "Allergic rhinitis", "E": "Chronic rhinosinusitis"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 25-year-old man is brought to the emergency department 30 minutes after he was involved in a motorcycle collision. Physical examination shows a deep laceration on the volar surface of the distal left forearm. Neurological examination shows loss of abduction and opposition of the left thumb. The radial and ulnar pulses are palpable. Based on these findings, which of the following nerves is most likely injured in this patient?", "answer": "Median nerve", "options": {"A": "Posterior interosseous nerve", "B": "Axillary nerve", "C": "Radial nerve", "D": "Median nerve", "E": "Ulnar nerve"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 70-year-old man presents to the emergency department after several episodes of bloody stools that started 6 hours ago. The patient denies nausea, vomiting, or diarrhea. On examination, he is pale and cachectic. The patient’s abdomen is nontender to palpation on the exam. His heart rate is 120/min and blood pressure is 80/60 mm Hg. A stool sample from the patient shows stools with bright red blood, and a hemoccult test is positive. Which of the following is the most likely location of his intestinal bleeding?", "answer": "Sigmoid colon", "options": {"A": "Ascending colon", "B": "Sigmoid colon", "C": "Duodenum", "D": "Stomach", "E": "Ileum"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 48-year-old man comes to the physician because of a 4-month history of persistent cough productive of white phlegm. He coughs consistently throughout the day, and he has not noticed any particular triggers that make it worse. He has also recently experienced some shortness of breath with exertion. He has not had any weight loss, fever, or chills. He had similar symptoms last year, which lasted about 6 months. He has hypertension, for which he takes amlodipine. He has worked in construction for the past 10 years. He has smoked a pack of cigarettes per day for 30 years. Vital signs are within normal limits. Examination shows an end-expiratory wheeze throughout all lung zones. Which of the following is the most likely diagnosis?", "answer": "Chronic bronchitis", "options": {"A": "Asbestosis", "B": "Hypersensitivity pneumonitis", "C": "Asthma", "D": "Chronic bronchitis", "E": "Adenocarcinoma"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 26-year-old female with no significant past medical history presents to the emergency department complaining of chest pain. She states that she was visiting her boyfriend in the hospital and, approximately 10 minutes ago, she developed chest pain associated with sweating, palpitations, nausea, and chills. She appears very nervous and states that she is scared that she is dying. Vital signs reveal tachycardia, hypertension, and tachypnea. An EKG is obtained that is unremarkable besides tachycardia. TSH and free T4 are within normal limits. A urine drug screen is obtained and it is negative. What is the best immediate treatment for this patient?", "answer": "Alprazolam, reassurance, encouraging patient to slow breathing", "options": {"A": "Morphine, oxygen, nitrogylcerin, aspirin, beta blockers, ACE inhibitor, and heparin", "B": "Alprazolam, reassurance, encouraging patient to slow breathing", "C": "Albuterol breathing treatment", "D": "SSRI therapy", "E": "Cognitive behavioral therapy"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 36-year-old woman is brought to the emergency department by her sister 1 hour after she was found unconscious at home. She appears lethargic. Her temperature is 37°C (98.6°F), pulse is 80/min, respirations are 5/min, and blood pressure is 120/70 mm Hg. Urine toxicology screening is positive for alcohol, benzodiazepines, and barbiturates. The patient's condition improves with supportive treatment, and she is admitted for psychiatric evaluation. Three days later, a physician colleague approaches the physician who treated the patient in the lobby of the hospital and states, “I just want to know what happened. I'm her neighbor and childhood friend, and I'm worried about her.” Which of the following responses by the treating physician is the most appropriate?", "answer": "\"\"\"I understand your concern, but I am unable to provide information about this situation.\"\"\"", "options": {"A": "\"\"\"You can find the information in the electronic medical record.\"\"\"", "B": "\"\"\"Why don't you go ahead and ask her directly? She is currently in the psychiatric ward.\"\"\"", "C": "\"\"\"Her urine toxicology screening was positive for alcohol, benzodiazepines, and barbiturates.\"\"\"", "D": "\"\"\"I'm not the right person to ask. Please ask her primary care physician.\"\"\"", "E": "\"\"\"I understand your concern, but I am unable to provide information about this situation.\"\"\""}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 40-year-old man presents to a clinic for a regular follow-up. He was diagnosed with Wilson’s disease 20 years ago and underwent a human leukocyte antigen–matched liver transplant 15 years ago. Today he is feeling fine and has no complaints except for a new, mild jaundice that his wife noticed a few weeks ago. He denies any changes in stool or urine color and is not having any abdominal pain. On physical examination, his vital signs are within normal limits, and only mild scleral icterus is noticed. Which of the following best describes the mechanism of rejection that happened in this patient?", "answer": "Donor allogeneic MHC molecules are taken up by recipient APCs and processed into peptides, and then the peptides are presented by recipient MHC molecules to recipient T cells.", "options": {"A": "Donor allogeneic MHC molecules are taken up by recipient APCs and processed into peptides, and then the peptides are presented by recipient MHC molecules to donor T cells.", "B": "Donor allogeneic MHC molecules are taken up by donor APCs and processed into peptides, and then the peptides are presented by unprocessed donor allogeneic MHC molecules to recipient T cells.", "C": "Donor allogeneic MHC molecules are shed from graft cells, inserted into recipient APCs, loaded with recipient peptides, and presented to recipient T cells.", "D": "Donor allogeneic MHC molecules are taken up by recipient APCs and processed into peptides, and then the peptides are presented by recipient MHC molecules to recipient T cells.", "E": "Recipient MHC molecules are taken up by donor APCs and processed into peptides, and then the peptides are presented by donor allogeneic MHC molecules to recipient T cells."}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 6-year-old boy is brought to his pediatrician due to increased shortness of breath. His mother is particularly disturbed because her son wakes up breathless one or 2 nights every week. He was diagnosed with asthma 2 years ago. Over the past few months, he has not been able to participate in any sport and is also using his inhaler more than 3 times a week. On examination, the patient appears to be in slight distress and seems pale and fatigued. There are slight expiratory wheezes and crackles in both lungs. The pediatrician starts him on a low dose of another inhaler which needs to be taken once daily. She asks his mother to avoid any conditions that might aggravate her son’s symptoms and make it difficult for him to breathe. Three months later, the mother is back with her son at the same pediatrician’s office. She is concerned about a painless white plaque on his tongue. When the physician scrapes the lesion it reveals a red base with minimal bleeding. A photograph of the lesion is shown. Which of the following was most likely prescribed during the previous visit?", "answer": "Inhaled beclomethasone", "options": {"A": "Nebulized albuterol", "B": "Inhaled beclomethasone", "C": "Inhaled ipratropium bromide", "D": "Nebulized theophylline", "E": "Inhaled salmeterol"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 25-year-old medical student enrolls in an exercise research study. Spirometry testing, along with arterial and venous blood gases, are performed immediately before and after 15 minutes of exercising on a stationary bicycle. How do you expect the venous pH, arterial pCO2, and venous pCO2 to respond?", "answer": "Venous pH decreases, arterial pCO2 stays the same, venous pCO2 increases", "options": {"A": "Venous pH decreases, arterial pCO2 decreases, venous pCO2 decreases", "B": "Venous pH decreases, arterial pCO2 increases, venous pCO2 increases", "C": "Venous pH increases, arterial pCO2 decreases, venous pCO2 increases", "D": "Venous pH increases, arterial pCO2 increases, venous pCO2 increases", "E": "Venous pH decreases, arterial pCO2 stays the same, venous pCO2 increases"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 38-year-old imprisoned man is brought to the physician after going on a hunger strike for 36 hours. During this time, he has only had two cups of water. Physical examination shows dry mucous membranes. His serum glucose concentration is 70 mg/dL. Which of the following enzymes contributes most to maintaining a normal serum glucose level in this patient?", "answer": "Phosphoenolpyruvate carboxykinase", "options": {"A": "Phosphoenolpyruvate carboxykinase", "B": "Hydroxymethylglutaryl-CoA lyase", "C": "Glycogen phosphorylase", "D": "Phosphofructokinase-1", "E": "Glucose-6-phosphate dehydrogenase"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 27-year-old man presents to the emergency department with a chief concern of abdominal pain and diarrhea. The patient states that for the past 4 days he has experienced abdominal pain, diarrhea, weakness and a subjective fever. He also endorses a weight loss of 11 pounds during this time. The patient has a past medical history of celiac disease, constipation, and depression. His current medications include fish oil, a multivitamin, sodium docusate, and fluoxetine. His temperature is 98.5°F (36.9°C), blood pressure is 110/75 mmHg, pulse is 90/min, respirations are 13/min, and oxygen saturation is 98% on room air. Physical exam is notable for a young man in mild distress. Cardiac and pulmonary exams are within normal limits. Abdominal exam is notable for generalized tenderness and increased bowel sounds. Oral exam is notable for multiple shallow painful ulcers. Laboratory values are ordered as seen below:\n\nHemoglobin: 12 g/dL\nHematocrit: 36%\nLeukocyte count: 8,000 cells/mm^3 with normal differential\nPlatelet count: 227,500/mm^3\n\nSerum:\nNa+: 141 mEq/L\nCl-: 101 mEq/L\nK+: 4.5 mEq/L\nHCO3-: 24 mEq/L\nBUN: 17 mg/dL\nGlucose: 82 mg/dL\nCreatinine: 1.0 mg/dL\nCa2+: 10.1 mg/dL\nAST: 12 U/L\nALT: 11 U/L\n\nA stool guaiac test is performed which returns positive. The patient is started on IV fluids and morphine. Which of the following best describes the most likely diagnosis?", "answer": "ASCA positivity", "options": {"A": "ANCA positivity", "B": "ASCA positivity", "C": "Bleeding arteriovenous malformation", "D": "Dilated vascular structure in the anal canal", "E": "Mucosal disruption"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A previously healthy 31-year-old man is rushed to the emergency department after an all-night binge that included smoking, alcohol, and cocaine. He complains of chest fluttering, fatigue, and lightheadedness. His past medical and family history are noncontributory. Social history is positive for occasional smoking and social drinking. At the hospital, the blood pressure is 110/70 mm Hg and the heart rate of 160/min and regular. The electrocardiogram (ECG) is shown. A physical maneuver involving massage of the neck is attempted without improvement. The patient is given the appropriate medication that improves his heart rate and returns his ECG to normal. Which of the following is the mechanism of action of the medication?", "answer": "Slowing of the atrioventricular (AV) node conduction time", "options": {"A": "Gamma-aminobutyric acid receptor agonist", "B": "Competitive antagonism of opiate receptors within the central nervous system", "C": "Slowing of the atrioventricular (AV) node conduction time", "D": "Blocking of sodium/potassium adenosine triphosphatase pump", "E": "Prolongation of repolarization phase of cardiac action potential"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A scientist is studying how animals regulate their blood pressure in response to various stimuli. In particular, she is interested in how much a novel compound that binds to both alpha-1 and beta-1 adrenergic receptors will affect blood pressure. She studies this question in non-human primates, but finds that her results are confounded by the fact that the animals' heart rates start to decrease several minutes after administration of this novel compound. She therefore decides to pretreat these animals with a drug that is known to prevent this decrease in heart rate. Which of the following drugs would most likely achieve the desired effect?", "answer": "Hexamethonium", "options": {"A": "Dobutamine", "B": "Hexamethonium", "C": "Physostigmine", "D": "Metoprolol", "E": "Scopolamine"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A hepatologist has learned about the survival benefit of Noxbinle (tumorolimus) in hepatocellular carcinoma (HCC) patients from a fellow physician. She is looking at a list of HCC patients on her hospital's hepatology consult service and trying to identify candidates who might derive more survival benefits from Noxbinle as opposed to Metalimus. Based on the information provided in the drug advertisement, which of the following patients with HCC would be an appropriate treatment candidate and benefit the most from treatment with Noxbinle 100 mg in comparison to Metalimus 100 mg?", "answer": "Patient with severe cirrhosis, history of hepatitis C, and asthma", "options": {"A": "Non-cirrhotic patient with a history of hepatitis B and alcohol dependence", "B": "Alcoholic patient with severe cirrhosis on immunosuppressive therapy", "C": "Patient with severe cirrhosis, history of hepatitis C, and kidney stones", "D": "Patient with severe cirrhosis, history of hepatitis C, and asthma", "E": "Alcoholic patient with moderate cirrhosis and a necrotic foot ulcer"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "An error occurs during the embryologic development of the kidney. It is found that the fetus lacks proper ureters, major and minor calyces, and renal pelvises. In this fetus, what other renal structure would be expected to be absent?", "answer": "Collecting ducts", "options": {"A": "Glomeruli", "B": "Collecting ducts", "C": "Ductus deferens", "D": "Distal convoluted tubule", "E": "Bowman's capsule"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "An investigator is studying the effects of tissue hypoxia on skeletal muscles. Skeletal muscle hypoxia is induced by decreasing oxygen delivery to peripheral tissues. Which of the following is most likely to achieve this desired effect?", "answer": "Decrease the serum 2,3-bisphosphoglycerate concentration", "options": {"A": "Decrease the serum 2,3-bisphosphoglycerate concentration", "B": "Increase the serum hydrogen ion concentration", "C": "Decrease the proportion of fetal hemoglobin", "D": "Increase the arterial partial pressure of carbon dioxide", "E": "Increase the serum temperature"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 48-year-old woman presents to the doctor’s office complaining of frequent episodes of severe heartburn and chest pain. It feels like food is getting stuck in her throat somewhere. She wakes up at night in fits of coughing and in pain. Antacids and other over the counter remedies do not improve the discomfort. The physician feels that the patient has acid reflux and recommends upper gastrointestinal endoscopy and a trial of omeprazole. Several biopsies are taken during the endoscopy: one from the distal esophagus, one from the gastroesophageal junction, and one from the body of the stomach. Which histological finding would place her at the highest risk of developing esophageal adenocarcinoma in the near future?", "answer": "The presence of high grade dysplasia at the Z line", "options": {"A": "The presence of stratified squamous epithelium at the Z line", "B": "The presence of inflammatory cells in the body of the stomach", "C": "The presence of metaplasia at the Z line", "D": "The presence of goblet cells at the Z line", "E": "The presence of high grade dysplasia at the Z line"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 26-year-old man comes to the physician because of a 3-week history of malaise and recurrent fever. He has also had a 4.5-kg (10-lb) weight loss over the past 3 months. He came back from his honeymoon in Kenya 6 months ago. He appears ill. His temperature is 39°C (102.2°F). He is alert and oriented to person, time, and place. Physical examination shows generalized lymphadenopathy and hepatosplenomegaly. Laboratory studies show a hemoglobin concentration of 9.1 g/dL, leukocyte count of 2,900/mm3, and platelet count of 108,000/mm3. Which of the following is the most likely vector of this patient's condition?", "answer": "Sand fly", "options": {"A": "Tsetse fly", "B": "Sand fly", "C": "Freshwater snail", "D": "Anopheles mosquito", "E": "Triatomine bug"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 68-year-old Caucasian male presents to your office complaining of urinary hesitancy and decreased urinary flow. His blood pressure is measured to be 168/95. You prescribe prazosin. Which best describes the principal action(s) of prazosin?", "answer": "Relaxation of urinary sphincter and reduction of peripheral vascular resistance", "options": {"A": "Relaxation of urinary sphincter and reduction of peripheral vascular resistance", "B": "Relaxation of urinary sphincter and suppression of renin release", "C": "Relaxation of urinary bladder wall smooth muscle and decreased cardiac contractility", "D": "Contraction of urinary bladder wall smooth muscle and suppression of renin release", "E": "Contraction of urinary bladder wall smooth muscle and reduction of peripheral vascular resistance"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 4-year-old boy is referred to the infectious disease clinic for recurrent pneumonia. Although he has had several previous hospital admissions and received multiple courses of antibiotic therapy, he continues to get sick. On his most recent hospital admission, the boy presented with mild fever, right-sided chest pain, and yellow-colored sputum. He had difficulty breathing and diminished breath sounds on the right side of the chest. A CT scan of the thorax revealed multiple right-sided ground-glass opacities. Sputum cultures grew Aspergillus galactomannan. The boy’s medical history is significant for neonatal sepsis and recurrent episodes of pyoderma and otitis media. His younger brother had recurrent purulent skin infections before he died of an otogenic brain abscess at the age of 2. His mother says that skin infections are common in the male members of her family. The patient’s HIV status is negative and his complete blood count, T cell and B cell counts, immunoglobulin profile, and complement tests are within normal limits. Which of the following is the next best step in the management of this patient?", "answer": "Dihydrorhodamine (DHR) test", "options": {"A": "CD4+ cell count", "B": "Bone marrow biopsy", "C": "Dihydrorhodamine (DHR) test", "D": "Flow cytometry for CD18+ cell deficiency", "E": "Adenosine deaminase levels"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 72-year-old man is being transported by emergency medical services to the emergency department for a stroke code. He was found on the ground by his daughter earlier today, and he was last known to be without neurological deficits two hours prior to presentation. His temperature is 99°F (37.2°C), blood pressure is 185/105 mmHg, pulse is 102/min, and respirations are 18/min. A non-contrast head CT is performed, which demonstrates a hypodense lesion affecting the left medial frontal and parietal lobe. Which of the following will most likely be found on physical exam?", "answer": "Contralateral lower extremity weakness", "options": {"A": "Contralateral hemiparesis", "B": "Contralateral lower extremity weakness", "C": "Contralateral upper extremity weakness", "D": "Hemineglect", "E": "Wernicke aphasia"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 33-year-old G1P0 at 39 weeks gestation is admitted to the labor and delivery floor for induction of labor. She feels well and is no acute distress. She is accompanied by her husband. Her past medical history is notable for major depressive disorder and generalized anxiety disorder. She takes sertraline. Her temperature is 99.2°F (37.3°C), blood pressure is 120/75 mmHg, pulse is 95/min, and respirations are 18/min. To initiate labor induction, the obstetrician injects the patient with a hormone that is endogenously made in the hypothalamus and released by the posterior pituitary. This medication is associated with an increased risk of which of the following complications?", "answer": "Placental abruption", "options": {"A": "Placental abruption", "B": "Vasa previa", "C": "Placenta accreta", "D": "Preeclampsia", "E": "Oligohydramnios"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 57-year-old Caucasian male presents to your office with heart palpitations and shortness of breath. On exam, he is tachycardic and his rhythm is irregularly irregular. He fails standard pharmacologic therapy and you refer to cardiology, where he is started on an antiarrhythmic medication. The action of this agent results in a longer action potential duration, an increased effective refractory period, and a longer QT interval. Which drug has been prescribed?", "answer": "Sotalol", "options": {"A": "Flecanide", "B": "Propafenone", "C": "Mexiletine", "D": "Diltiazem", "E": "Sotalol"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 2-year-old girl is brought to the physician because of abdominal distention and twitching of her feet, which her mother noticed a week ago. The patient has also had a low-grade fever for 5 days. She has not had a bowel movement in 3 days. She was born at term and has been healthy since. She is at the 40th percentile for height and 20th percentile for weight. Her temperature is 38.1°C (100.6°F), pulse is 128/min, and blood pressure is 135/82 mm Hg. Examination shows an irregular palpable mass that crosses the midline of the abdomen. The liver is palpated 3 cm below the right costal margin. There are erratic movements of the eyes. A 24-hour urine collection shows elevated homovanillic acid and vanillylmandelic acid levels. Which of the following is the most likely diagnosis?", "answer": "Neuroblastoma", "options": {"A": "Hodgkin lymphoma", "B": "Pheochromocytoma", "C": "Hepatoblastoma", "D": "Nephroblastoma", "E": "Neuroblastoma"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 53-year-old man is brought to the emergency department by his wife after the sudden onset of dizziness, nausea, and left-sided weakness. His blood pressure is 165/95 mm Hg. Neurological examination shows decreased muscle tone and hyperreflexia in the right upper and lower extremities. His gait is unsteady, and he falls to the left when attempting to walk. Finger-to-nose testing shows dysmetria on the left side. A CT scan of the head shows a small lesion in the left lateral pons that involves the nucleus of a cranial nerve that exits the brain at the middle cerebellar peduncle. Which of the following additional findings is most likely in this patient?", "answer": "Difficulty chewing and deviation of the jaw to the left", "options": {"A": "Ptosis and inability to look up with the right eye", "B": "Deviation of the tongue to the left when protruded", "C": "Winging of the left scapula and weakness turning the head to the right", "D": "Difficulty chewing and deviation of the jaw to the left", "E": "Inability to smell vanilla or coffee"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 38-year-old African American female presents to her primary care physician with uveitis, cough, and arthralgias in her ankles and legs. Bloodwork reveals elevated angiotensin converting enzyme levels, and skin PPD testing shows no observable induration after 48 hours. The patient demonstrates reduced FEV1 and FVC upon spirometry. FEV1/FVC is 85%. Which of the following would you expect to see upon chest X-ray:", "answer": "Enlarged hilar lymph nodes", "options": {"A": "Enlarged hilar lymph nodes", "B": "Kerley B Lines", "C": "Bilateral diaphragmatic elevation.", "D": "Pleural effusion", "E": "Fluid in alveolar walls"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A previously healthy 41-year-old man comes to the physician for evaluation of a 1-month history of painless, intermittent bleeding on defecation, which he discovered while wiping. His younger sister was recently diagnosed with endometrial cancer, and his mother was diagnosed with gastric cancer at 58 years of age. Physical examination shows no abnormalities. Test of the stool for occult blood is positive. Colonoscopy shows a tumor in the ascending colon. Histopathologic examination of the tumor shows a mucinous, poorly-differentiated adenocarcinoma. A mutation of which of the following genes is most likely responsible for this patient's condition?", "answer": "MLH1", "options": {"A": "MLH1", "B": "TP53", "C": "DCC", "D": "KRAS", "E": "APC"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 49-year-old woman presents to her pulmonologist for a follow-up visit. She reports a longstanding history of chronic dyspnea and fatigue. Her past medical history is notable for asthma. She has a known mutation in the BMPR2 gene. She was recently trialed on nifedipine but stopped due to severe lower extremity edema. She does not smoke and does not drink alcohol. Her temperature is 99.4°F (37.4°C), blood pressure is 135/80 mmHg, pulse is 80/min, and respirations are 20/min. Physical examination reveals an increased P2 on cardiac auscultation. Her physician recommends starting a medication to slow the patient’s clinical worsening that requires regular monitoring of liver function tests. This medication has which of the following mechanisms of action?", "answer": "Endothelin-1 receptor antagonist", "options": {"A": "Endothelin-1 receptor antagonist", "B": "Beta-2-adrenergic receptor agonist", "C": "Phospholipase A2 antagonist", "D": "Phosphodiesterase type 5 antagonist", "E": "Prostacyclin agonist"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 14-year-old girl is brought to the physician by her mother for the evaluation of recurrent episodes of nose bleeding for several months. The episodes occur unexpectedly and stop after a few minutes by elevating the upper body and bending the head forward. Menses occur at regular 27-day intervals with heavy flow. Her last menstrual period was 3 weeks ago. Vital signs are within normal limits. Physical examination shows no abnormalities. Laboratory studies show:\nHemoglobin 11 g/dL\nHematocrit 34%\nLeukocyte count 7,000/mm3\nPlatelet count 180,000/mm3\nProthrombin time 13 sec\nPartial thromboplastin time 45 sec\nFibrin split products negative\nThe bleeding time is 10 minutes. Which of the following is the most appropriate next step in treatment?\"", "answer": "Desmopressin", "options": {"A": "Oral prednisone", "B": "Intravenous immunoglobulins", "C": "Vitamin K injection", "D": "Tranexamic acid", "E": "Desmopressin"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 29-year-old G3P2 undergoes a cesarean section at 38 weeks gestation and delivers a boy weighing 4570 g with Apgar scores of 5 and 8 at 1 and 5 minutes, respectively. The current pregnancy was complicated by gestational diabetes with poor glycemic control. The newborn’s heart rate is 122/min, the respiratory rate is 31/min, and the temperature 36.4℃ (97.5℉). On examination, the newborn is pale, lethargic, diaphoretic, and has poor muscular tone. The liver is 2 cm below the right costal margin. Which of the following is the most probable cause of the newborn’s condition?", "answer": "Hyperinsulinemia", "options": {"A": "Microangiopathy", "B": "Hyperinsulinemia", "C": "Hyperglycemia", "D": "Hyperbilirubinemia", "E": "Polycythemia"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 19-year-old woman is brought to the emergency department by ambulance after experiencing a first-time seizure. She as preparing for an exam at her college’s library, in her normal state of health and collapsed. When she regained consciousness she was surrounded by students and staff. The emergency personnel assessed her condition and brought her in. Past medical history is significant for major depressive disorder. Her primary care physician prescribed a medication for her depression, but she has not taken it for several days because she was concerned about weight gain. Family medical history is insignificant for neurological disorders. Instead, for the past 10 days, she has been taking her roommate’s antidepressant medication instead. Today her blood pressure is 100/80 mm Hg, pulse 102/min, respirations 12/min and he BMI is 15 kg/m2. Physical examination reveals pale and dry mucosa and conjunctiva, and lanugo on her arms and legs. What medication is the patient most likely taking?", "answer": "Bupropion", "options": {"A": "Paroxetine", "B": "Bupropion", "C": "Gabapentin", "D": "Selegiline", "E": "Amitriptyline"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 59-year-old man with long-standing hypertension is brought to the emergency department because of vomiting and headache for 2 hours. He reports that he has been unable to refill the prescription for his antihypertensive medications. His blood pressure is 210/120 mm Hg. Fundoscopy shows bilateral optic disc swelling. An ECG shows left ventricular hypertrophy. Treatment with intravenous fenoldopam is begun. Which of the following intracellular changes is most likely to occur in renal vascular smooth muscle as a result of this drug?", "answer": "Increased production of cyclic adenosine monophosphate", "options": {"A": "Increased activity of myosin light-chain kinase", "B": "Increased activity of protein kinase C", "C": "Increased activity of guanylate cyclase", "D": "Increased production of cyclic adenosine monophosphate", "E": "Increased intracellular concentration of calcium"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 4-year-old boy is referred to the transfusion clinic with malaise, fever, bilateral conjunctivitis, erythema of the oral mucosa, macular rash of the trunk, and inguinal lymphadenopathy following several days of loose stool. The boy was born at 39 weeks gestation via spontaneous vaginal delivery. He is up to date on all vaccines and is meeting all developmental milestones. Kawasaki’s disease is suspected and therapy with intravenous immunoglobulin and aspirin is initiated. Later that day, the patient develops trouble breathing, facial flushing, and rapidly evolving pruritic abdominal rash. He is rushed to the emergency department where his blood pressure is 85/48 mm Hg, heart rate is 120/min, respiratory rate is 26/min, and temperature is 37.0°C (98.6°F). On physical examination, the patient has severe facial edema and severe stridor, which can be heard without a stethoscope. A complete blood count is normal. Of the following options, which underlying condition could cause this reaction?", "answer": "IgA deficiency", "options": {"A": "Bruton's agammaglobulinemia", "B": "IgA deficiency", "C": "Hyper-IgM syndrome", "D": "Common variable immunodeficiency", "E": "Hyper-IgD syndrome"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 19-year-old man presents to the physician due to progressively worsening weakness. He also notes that he has been getting tired easily and frequently feels short of breath. Additionally, he notes a protuberant belly that he cannot seem to reduce with diet and exercise. His past medical history is significant for easy bruising since he was very young, requiring at least one transfusion when he was younger. He takes no medications. His blood pressure is 125/92 mm Hg, pulse is 90/min, respiratory rate 12/min, and temperature is 36.6°C (97.9°F). Physical examination reveals hepatomegaly and splenomegaly. Several bruises can be seen on the inside of his arms and legs. Laboratory testing shows:\nHematocrit 23%\nErythrocyte count 2.2 million/mm3\nThrombocyte count  25,000/mm3\nA bone marrow biopsy shows decreased trilineage hematopoiesis and macrophages with a crinkled tissue-paper appearance. What is the mode of inheritance for this patient's disease?", "answer": "Autosomal recessive", "options": {"A": "Autosomal dominant", "B": "X-linked recessive", "C": "Autosomal recessive", "D": "Mitochondrial inheritance", "E": "X-linked dominant"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 1-day-old boy is brought to the emergency room by his parents for difficulty breathing. He was delivered at home via vaginal birth with no complications. The mom received minimal prenatal care as she wanted the most natural process for her child. The mom reports that he has been relatively healthy expect for when he feeds he gets a little fussy. However, these episodes self-resolve after he curls up his legs. A physical examination demonstrates a baby in acute distress with subcostal retractions and cyanosis at the distal extremities. A 5/6 systolic ejection murmur is heard at the left upper sternal border. What is the best next step in terms of managing this patient?", "answer": "Give prostaglandin E1", "options": {"A": "Administer warming blankets", "B": "Give prostaglandin E1", "C": "Give antibiotics", "D": "Immediate surgical repair", "E": "Obtain lumbar puncture for CSF analysis"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 40-year-old woman schedules an appointment for a routine medical check-up. She admits to being careless about her health, but is motivated to improve. She is working with a personal trainer at the gym and is following a weight reduction diet plan. Despite a 20 kg (44 lb) weight loss over the last year, she still feels that she is fat. She was a frequent binge drinker, but now she has reduced her alcohol consumption to a single glass of wine with dinner and an occasional beer on the weekend. She also has a 15 pack-year smoking history, but quit 6 months ago after she developed a cough and shortness of breath that later improved. She admits to trying various recreational drugs in the past. On her last visit, she was started on rosuvastatin for an elevated cholesterol level. She is sexually active with her partner and they have 2 children. She is uncertain about her family history as she was raised in foster care. The vital signs include: pulse 80/min, respirations 16/min, and blood pressure 122/80 mm Hg. The physical examination reveals a visibly overweight woman with a body mass index (BMI) of 34 kg/m2. The remainder of the examination yields no significant findings. An electrocardiogram (ECG) and chest X-ray are both normal. Lab tests show the following:\nSerum glucose (fasting) 95 mg/dL\n    Serum electrolytes:\nSodium 140 mEq/L\nPotassium 3.8 mEq/L\nChloride 101 mEq/L\nSerum creatinine 0.8 mg/dL\nBlood urea nitrogen 10 mg/dL\nCholesterol, total 180 mg/dL\nHDL-cholesterol 42 mg/dL\nLDL-cholesterol 70 mg/dL\nTriglycerides 365 mg/dL\n    Urinalysis:  \nGlucose negative\nKetones negative\nLeucocytes negative\nNitrites negative\nRBC negative\nCasts negative\nWhich medication would most likely further improve her lipid profile?", "answer": "Fenofibrate", "options": {"A": "Niacin", "B": "Cholestyramine", "C": "Orlistat", "D": "Fenofibrate", "E": "Ezetimibe"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 59-year-old man presents to the emergency department with abdominal pain. He states that it seemed to come on abruptly, though he does endorse feeling pain the past several days. He has been experiencing bloody diarrhea as well as a subjective fever. His past medical history is notable for an ST elevation myocardial infarction (STEMI) treated 1 year ago, an abdominal aortic aneurysm (AAA) treated 1 week ago, chronic obstructive pulmonary disease (COPD), asthma, obesity, hypertension, stroke treated 5 years ago, an atrial arrhythmia, diabetes, constipation, and post-traumatic stress disorder (PTSD). His temperature is 102.0°F (39°C), blood pressure is 197/128 mmHg, pulse is 135/min, respirations are 22/min, and oxygen saturation is 92% on room air. On physical exam, you note an obese man in distress. Cardiopulmonary exam is notable for bilateral wheezes and a systolic murmur. There is bilateral lower extremity pitting edema and venous stasis ulcers. Abdominal exam reveals diffuse tenderness which the patient describes as 10/10 in severity. Laboratory values are ordered as seen below.\n\nHemoglobin: 14 g/dL\nHematocrit: 42%\nLeukocyte count: 15,500/mm^3 with normal differential\nPlatelet count: 199,000/mm^3\n\nSerum:\nNa+: 139 mEq/L\nCl-: 100 mEq/L\nK+: 4.4 mEq/L\nHCO3-: 22 mEq/L\nBUN: 32 mg/dL\nGlucose: 189 mg/dL\nCreatinine: 1.9 mg/dL\nCa2+: 10.2 mg/dL\nLactate: 4.5 mg/dL\nAST: 12 U/L\nALT: 10 U/L\n\nWhich of the following is the most likely explanation for this patient's presentation?", "answer": "Abdominal aortic aneurysm repair complication", "options": {"A": "Abdominal aortic aneurysm repair complication", "B": "Atheromatous plaque rupture", "C": "Atrial fibrillation", "D": "Obstruction of the small bowel", "E": "Ruptured appendix"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "An investigator is studying an experimental treatment for HIV infection that inhibits the maturation of new HIV virions. Patients who are taking the drug are observed for several years and side effects are recorded. A correlation is established between the drug and the development of impaired glucose tolerance. In addition, a significant portion of the patients who take the drug for several years shows increased fat accumulation in the neck with loss of subcutaneous fat in the face and extremities. Which of the following processes is most likely targeted by this drug?", "answer": "Viral polypeptide cleavage", "options": {"A": "Viral entry into host cell", "B": "Viral polypeptide cleavage", "C": "Viral DNA integration into host DNA", "D": "Viral budding from host cells", "E": "Reverse transcription of viral RNA"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 30-year-old G1P1 woman gives birth to a healthy infant at 39 weeks gestation. The mother attended all her prenatal visits and took all her appropriate prenatal vitamins. Her past medical history is notable for diabetes mellitus, for which she takes metformin. Apgar scores were 8 and 9 at 1 and 5 minutes, respectively. The infant's temperature is 99.2°F (37.3°C), blood pressure is 65/40 mmHg, pulse is 110/min, and respirations are 22/min. On exam, the child has ambiguous genitalia. A karyotype analysis demonstrates the presence of a Y chromosome. Further workup reveals internal testes with normal levels of serum luteinizing hormone and testosterone. Which of the following additional findings would most likely be seen in this patient?", "answer": "Testosterone-to-dihydrotestosterone ratio > 20", "options": {"A": "Decreased androgen receptor responsiveness", "B": "Impaired sense of smell", "C": "Long extremities", "D": "Testosterone-to-dihydrotestosterone ratio < 1", "E": "Testosterone-to-dihydrotestosterone ratio > 20"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "An investigator is studying the pharmacokinetic properties of two novel inhalational anesthetics and reports the following findings.\nBlood-gas partition coefficient Minimum alveolar concentration\nDrug A 0.42 3.20%\nDrug B 2.31 7.45%\nWhich of the following statements best describes the properties of drug A when compared to drug B?\"", "answer": "More lipid-soluble and faster recovery from anesthesia", "options": {"A": "More blood soluble and faster induction of anesthesia", "B": "More potent and slower recovery from anesthesia", "C": "More lipid-soluble and faster recovery from anesthesia", "D": "Less lipid soluble and slower induction of anesthesia", "E": "Less potent and faster induction of anesthesia"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 56-year-old man presents to an initial visit to his primary care physician complaining of excessive fatigue, weight loss, and increased abdominal girth. He drinks about 2–4 glasses of wine with dinner and recalls having abnormal liver enzymes in the past. He has a remote history of intravenous drug use. Physical examination reveals shifting dullness, firm liver, and splenomegaly. The skin lesion in this photo is present in on the face, arms, and upper trunk of the patient. Which of the following best describes the mechanism of development of these skin lesions in this patient?", "answer": "Hormonal imbalance", "options": {"A": "Anastomoses between portal vein tributaries and the arterial system", "B": "Hormonal imbalance", "C": "Decreased oncotic pressure", "D": "Coagulation defects", "E": "Increase in serum ammonia"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 44-year-old man presents to the emergency department due to sudden chest pain and difficulty breathing for the past 3 hours. The pain is felt in the retrosternal area and radiates up to his left shoulder and arm; it worsens on inspiration, and is relieved when he is leaning forward. His heart rate is 61/min, respiratory rate is 16/min, temperature is 36.5°C (97.7°F), and blood pressure is 115/78 mm Hg. Physical examination shows no abnormalities. Pericardial friction rub is heard on auscultation. Laboratory results show elevated erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) levels. An ECG is performed. Which of the following is the most likely diagnosis?", "answer": "Acute pericarditis", "options": {"A": "Acute pericarditis", "B": "Angina pectoris", "C": "Aortic stenosis", "D": "Infective endocarditis", "E": "Myocardial infarction"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 27-year-old woman comes to the physician because of a rash and headache. She recently returned from a camping trip in North Carolina. She has a severe allergy to doxycycline. Her temperature is 38.2°C (100.8°F). Physical examination shows a blanching erythematous rash and petechiae over both ankles and the soles of her feet. A drug is prescribed that can cause fatal aplastic anemia. The bacteriostatic effect of this drug is most likely due to which of the following mechanisms?", "answer": "Inactivation of bacterial peptidyltransferase at the 50S ribosomal subunit", "options": {"A": "Inhibition of initiation complex formation at the 30S ribosomal subunit", "B": "Inactivation of prokaryotic topoisomerase II and IV", "C": "Inhibition of tRNA binding site at the 30S ribosomal subunit", "D": "Inhibition of peptide translocation at the 50S ribosomal subunit", "E": "Inactivation of bacterial peptidyltransferase at the 50S ribosomal subunit"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "The research of an academic physician helps to discover a novel small molecule that improves outcomes after myocardial infarction in animal models due to decreasing the severity of reperfusion injury. A pharmaceutical company then approached the university of this physician in order to sign an agreement allowing the molecule to proceed to clinical trials. After several years of work, the physician has obtained a wealth of new data from human trials and has published several high profile papers.\n\nA major national conference then invites this physician to give a keynote presentation on his work with the novel small molecule. In order to prepare for this speech, the pharmaceutical company offers:\n1. A speaking honorarium\n2. Compensation for travel expenses\n3. Help with preparing slides for the speech\n\nWhich of these benefits can the physician ethically accept?", "answer": "1 and 2", "options": {"A": "1 only", "B": "3 only", "C": "1 and 2", "D": "1 and 3", "E": "1, 2, and 3"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 6-year-old boy is brought to the pediatrician with swelling around the eyes, lower extremity edema, and abdominal distension for the past 3 days. There is no history of hematuria or decreased urine output. His temperature is 36.9°C (98.4°F), pulse rate is 88/min, blood pressure is 98/70 mm Hg, and respiratory rate is 20/min. On physical examination, 2+ pitting edema is present in the lower limbs and the periorbital region. The abdomen is distended with a positive fluid wave. Laboratory studies show:\nSerum creatinine 0.8 mg/dL\nSerum albumin 1.5 g/dL\nSerum cholesterol 260 mg/dL\nSerum C3 and C4 Normal\nUrine protein/creatinine ratio 3.1 mg/mg\nThe patient is diagnosed with minimal change disease. Which of the following options best describes the pathogenesis of edema in this patient?", "answer": "Decreased oncotic pressure gradient across capillary", "options": {"A": "Increased capillary hydrostatic pressure", "B": "Increased capillary permeability", "C": "Increased interstitial oncotic pressure", "D": "Decreased oncotic pressure gradient across capillary", "E": "Lymphatic obstruction"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 73-year-old woman is brought to the physician by her son because of a 2-year history of increasing forgetfulness. She does not remember her children's names; she cannot go outside the house unaccompanied because she forgets where she is and what she is supposed to do. Her son reports that over the past year, she has withdrawn herself from social gatherings and avoids making conversation. Mental status examination shows both impaired short- and long-term memory. She is oriented only to person. Her abstract reasoning is impaired. She appears indifferent about her memory lapses and says this is normal for someone her age. This patient's condition is most likely associated with decreased production of which of the following substances?", "answer": "Acetylcholine", "options": {"A": "Gamma-aminobutyric acid", "B": "Acetylcholine", "C": "Norepinephrine", "D": "Serotonin", "E": "Dopamine"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "During an emergency room shift, you encounter a disheveled looking man claiming that he is President Kennedy’s love child and the FBI is out to get him. He also endorses that the aliens are responsible for his fathers death and that the aliens implanted a chip in his head to constantly speak to him. Upon review of his medical record, you notice that he made a previous visit to the ER for a similar episode about 8 months ago. Besides his eccentric demeanor and disorganized speech, his vitals and physical exam are all within in normal range. No illicit substances were identified following a urinary toxicology screening. What type of medication would be best long-term for our patient?", "answer": "Quetiapine", "options": {"A": "Quetiapine", "B": "Lithium", "C": "Fluoxetine", "D": "Chlorpromazine", "E": "Escitalopram"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 20-year-old man presents to an outpatient clinic with complaints of fever and sweating for 2 months. He says that he does not have the same appetite as before. He lost 2.7 kg (6.0 lb) in the last 2 months. He also complains of pleuritic chest pain and difficulty breathing, which is not nocturnal and is unrelated to position. He has had a mild cough for several months. On examination, the patient is afebrile with normal auscultatory findings. A chest X-ray reveals a right upper lobe homogeneous density. Ziehl-Neelsen staining of sputum shows Mycobacterium tuberculosis. What is the most likely pathological process seen in this type of infection?", "answer": "Caseous necrosis", "options": {"A": "Coagulative necrosis", "B": "Caseous necrosis", "C": "Liquefactive necrosis", "D": "Fat necrosis", "E": "Fibrinoid necrosis"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 19-year-old man presents with a 10-day history of progressive lower back pain and leg weakness, followed by severe lower abdominal pain for the past 12-hours. He describes the back pain as moderate in intensity which radiates to both legs. The weakness has progressively increased, and he cannot ambulate without support. He is also complaining of fever but never checks it. He is a captain of the college basketball team and the back pain and lower limb weakness is preventing him from participating in practices or games. Past medical history is significant for schizophrenia and a suicide attempt. His vital signs include: blood pressure 128/84 mm Hg, temperature 38.8°C (101.8°F). A mass is palpable in the lower abdomen. Strength is 5 out of 5 in the upper limbs bilaterally and 3 out of 5 in the lower limbs bilaterally. Deep tendon reflexes are 2+ in the upper limbs while they are reduced in the lower limbs. Sensitivity to pinprick is absent from below the umbilicus. 1270 mL of urine is collected after placing a Foley catheter. Which of the following is the next best step in the management of this patient?", "answer": "Spinal magnetic resonance imaging (MRI)", "options": {"A": "Intravenous steroids", "B": "Nerve conduction studies", "C": "Psychiatric consultation", "D": "Spinal magnetic resonance imaging (MRI)", "E": "Ultrasound of kidneys, ureters, and bladder"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 72-year-old man is diagnosed with multiple myeloma. His blood work shows mild anemia and urinalysis detects proteinuria at a level of 670 mg/24 h. A kidney biopsy is performed. Which of the following deposits would most likely be detected on the renal biopsy in this patient?", "answer": "AL amyloid", "options": {"A": "Аβ amyloid", "B": "Calcitonin", "C": "AL amyloid", "D": "Mutated transthyretin", "E": "Amylin"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 29-year-old woman, gravida 1, para 0 at 11 weeks' gestation, comes to the physician because of a 2-day history of left lower-extremity pain and swelling. Her temperature is 37.9°C (100.2°F). She denies any trauma but says she has not been ambulating due to swelling and the pain in her lower extremities. Physical examination shows diffuse pain on palpation and swelling of the left leg, as well as warmth and tenderness. Compression ultrasound shows poor compressibility of the femoral vein. Which of the following options would be most appropriate for the management of this patient?", "answer": "Heparin", "options": {"A": "Aspirin", "B": "Dipyridamole", "C": "Fondaparinux", "D": "Heparin", "E": "Warfarin"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 65-year-old woman presents to the emergency department with a new-onset seizure. The patient was at home watching television when she suddenly began jerking her limbs and not responding according to her partner. The patient works as a gardener is often dehydrated but drinks large volumes of water to compensate for her work. She does not wear protective gear or sunscreen while working. She has smoked 1.5 packs of cigarettes per day for the past 40 years. She drinks liquor before bed every night. The patient has a past medical history of hypertension and diabetes and recently lost 9 pounds. Physical exam is within normal limits. Which of the following is the most likely underlying diagnosis in this patient?", "answer": "Small cell carcinoma of the lung", "options": {"A": "Glioblastoma multiforme", "B": "Hyponatremia", "C": "Infiltrating ductal carcinoma of the breast", "D": "Primary seizure disorder", "E": "Small cell carcinoma of the lung"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 32-year-old man presents to the emergency department after puncturing his foot while working on his garage last week. His past medical history is significant for bronchial asthma and seasonal allergies. On examination, the patient’s jaw seems rigid, and his temperature is 38.3°C (100.9°F). The puncture on the sole of his foot is 2 cm deep and 0.5 cm long. The patient is immediately given tetanus immunoglobulin. What is inoculation of the tetanus vaccine able to stimulate the production of?", "answer": "Allotype antibodies", "options": {"A": "Anti-tetanus antibodies", "B": "Allotype antibodies", "C": "Hypersensitive reaction type III", "D": "Idiotype antibodies", "E": "Isotype antibodies"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 28-year-old woman presents to the clinic with 2 months of palpitations, tremor, heat intolerance, insomnia, and loose bowel movements. She has lost 20 kg (44 lb). A physical examination indicates that the body temperature is 37.8°C (100.0°F), the heart rate is 120/min, and the blood pressure is 130/80 mm Hg. The examination also reveals that a moderately-sized diffuse goiter and a bruit were present. She was agitated and experienced a fine tremor with warm moist palms; she also had increased deep tendon reflexes. No exophthalmos was noted. The laboratory tests revealed TSH < 0.01 mIU/L (normal: 0.5–4.0 mIU/L), T4: 57 pmol/L (normal: 10–25 pmol/L), T3: 24 pmol/L (normal 3.1–5.4 pmol/L). Complete blood count was normal. A thyroid scan demonstrated diffusely increased uptake. A high level of thyroid-stimulating immunoglobulin antibodies was detected. Which of the following explains these findings?", "answer": "Graves’ disease", "options": {"A": "Exogenous thyroxine intake", "B": "Graves’ disease", "C": "Hashimoto’s thyroiditis", "D": "Pregnancy", "E": "De Quervain thyroiditis"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 45-year-old woman comes to the physician because of fatigue and irregular menstrual cycles for the past year. She also complains of recurrent sinus infections. During the past 6 months, she has had increased urinary frequency and swelling of her feet. She has also had difficulty lifting her 3-year-old niece for the past 3 weeks. She was recently diagnosed with depression. She works as a medical assistant. The patient has smoked one half-pack of cigarettes daily for 25 years and drinks four beers on the weekends. Her only medication is escitalopram. She is 160 cm (5 ft 3 in) tall and weighs 79 kg (175 lb); BMI is 31 kg/m2. She appears tired. Her temperature is 37°C (98.6°F), pulse is 80/min, respirations are 18/min, and blood pressure is 140/82 mm Hg. Physical examinations shows neck obesity and an enlarged abdomen. Examination of the skin shows multiple bruises on her arms and legs. There is generalized weakness and atrophy of the proximal muscles. Laboratory studies show:\nSerum\nNa+ 150 mEq/L\nK+ 3.0 mEq/L\nCl- 103 mEq/L\nHCO3- 30 mEq/L\nUrea nitrogen 19 mg/dL\nCreatinine 0.9 mg/dL\nGlucose 136 mg/dL\nA 1 mg overnight dexamethasone suppression test shows a serum cortisol of 167 nmol/L (N < 50) and a 24-hour urinary cortisol is 425 μg (N < 300 μg). Serum ACTH is 169 pg/mL (N = 7–50). Subsequently, a high-dose dexamethasone suppression test shows a serum cortisol level of 164 nmol/L (N < 50). Which of the following is the most likely underlying cause of this patient's symptoms?\"", "answer": "Small cell lung cancer", "options": {"A": "Adrenal carcinoma", "B": "Hypothyroidism", "C": "Pheochromocytoma", "D": "Small cell lung cancer", "E": "Adrenal adenoma"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 39-year-old woman, gravida 3, para 2, at 39 weeks' gestation is admitted to the hospital with leakage of fluid and contractions. She noticed the fluid leak about an hour ago and has no associated bleeding. Contractions have been about 20 minutes apart. On admission, she is dilated 2 cm, 50% effaced, and at -2 station. Spontaneous rupture of membranes is confirmed and she is monitored by external tocodynamometer. Repeat evaluation after 2 hours shows dilation of 6 cm , 70% effacement, and -1 station. Four hours later, her pelvic exam shows no changes and she has 4 strong contractions every 10 minutes. The fetal heart rate is 120/min, with moderate accelerations and no late or variable decelerations. Which of the following is the most appropriate next step in management?", "answer": "Cesarean delivery", "options": {"A": "Cesarean delivery", "B": "Assisted vaginal delivery", "C": "Oxytocin infusion", "D": "Amnioinfusion", "E": "Intrauterine pressure catheter\n\""}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 32-year-old homeless man presents to the emergency department with dyspnea, left-sided chest pain, chills, and a productive cough over the last week or so. He does not have medical insurance and has not seen a doctor for many years. His chest pain increases with inspiration. The pain does not radiate or worsen with movement. He states that has a productive cough with yellow sputum with flecks of blood. He drinks 6 beers a night and does not smoke or take illicit drugs. Temperature is 37.8°C (100.0°F), blood pressure is 124/90 mm Hg, pulse is 92/min, and respiration rate is 16/min. On physical examination, tactile fremitus is increased and there is a dullness to percussion over the lower part of the left lung. No murmurs are heard. Oral examination reveals poor dentition. Chest X-ray reveals a large left lobar opacification with extensive pleural effusion. Which of the following is the best initial management for this patient?", "answer": "IV antibiotics and thoracentesis", "options": {"A": "Supplemental oxygen", "B": "IV antibiotics", "C": "IV antibiotics and thoracentesis", "D": "Inhaled bronchodilators", "E": "Upper endoscopy"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 43-year-old woman presents with left calf pain. She denies any previous episodes of such pain. Past medical history is significant for cervical carcinoma treated with cryosurgery with no evidence of recurrence. Current medications are an estrogen-containing oral contraceptive and a multivitamin. The patient reports a 40-pack-year smoking history, but no alcohol or recreational drug use. The patient is afebrile and her vital signs are within normal limits. On physical examination, her left calf is swollen, erythematous, and tender to palpation. A D-dimer level is positive. Which of the following is the most likely etiology of this patient’s condition?", "answer": "Oral contraceptives", "options": {"A": "Fibromyalgia", "B": "Occult malignancy", "C": "Oral contraceptives", "D": "Protein C deficiency", "E": "Protein S deficiency"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 53-year-old woman with hypertension and hyperlipidemia comes to the physician because of a 3-month history of progressively worsening shortness of breath. Her pulse is 92/min, respirations are 22/min, and blood pressure is 110/70 mm Hg. Cardiac examination shows a grade 3/6 holosystolic murmur at the apex that radiates to the axilla and an extra heart sound during early diastole. Assuming all other parameters remain constant, which of the following is most likely to decrease the volume of retrograde blood flow in this patient?", "answer": "Decrease in systemic vascular resistance", "options": {"A": "Increase in atrioventricular orifice size", "B": "Decrease in left atrial systolic pressure", "C": "Increase in left ventricular inotropy", "D": "Decrease in systemic vascular resistance", "E": "Increase in left ventricular end-diastolic pressure"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 66-year-old man presents to his primary care physician with abdominal pain in the setting of progressively worsening constipation. He complains of epigastric pain that waxes and wanes, and expressed concern that he has not defecated for the past 5 days. Upon further questioning, he relates that he has been taking three of his wife's multivitamins each day for the past three weeks to \"combat a cold.\" Vital signs are within normal limits. Physical exam reveals an abdomen with nonspecific tenderness to deep palpation without rebound tenderness, hyperpercussion, or flank tenderness. What is the most likely cause of his symptoms?", "answer": "Iron overdose", "options": {"A": "Magnesium overdose", "B": "Iron overdose", "C": "Potassium overdose", "D": "Folic acid overdose", "E": "Zinc overdose"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "Two days after undergoing transsphenoidal removal of a pituitary macroadenoma, a 35-year-old woman reports increased thirst and frequent urination. The surgery was uncomplicated. Neurologic examination shows no abnormalities. Her serum sodium concentration is 153 mEq/L and serum glucose concentration is 92 mg/dL. Which of the following findings in the nephron best describes the tubular osmolality, compared with serum, in this patient?", "answer": "Collecting duct is hypotonic", "options": {"A": "Distal ascending loop of Henle is hypertonic", "B": "Distal descending loop of Henle is hypotonic", "C": "Proximal convoluted tubule is hypertonic", "D": "Collecting duct is hypotonic", "E": "Distal convoluted tubule is hypertonic"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 67-year-old woman comes to the physician because of a 5-day history of episodic abdominal pain, nausea, and vomiting. She has coronary artery disease and type 2 diabetes mellitus. She takes aspirin, metoprolol, and metformin. She is 163 cm (5 ft 4 in) tall and weighs 91 kg (200 lb); her BMI is 34 kg/m2. Her temperature is 38.1°C (100.6°F). Physical examination shows dry mucous membranes, abdominal distension, and hyperactive bowel sounds. Ultrasonography of the abdomen shows air in the biliary tract. This patient's symptoms are most likely caused by obstruction at which of the following locations?", "answer": "Distal ileum", "options": {"A": "Third part of the duodenum", "B": "Distal ileum", "C": "Hepatic duct", "D": "Proximal jejunum", "E": "Pancreatic duct"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 47-year-old man presents to his ophthalmologist for abnormal vision. The patient was discharged from the hospital 2 weeks ago after a motor vehicle accident where he was given 1L of blood. He also underwent several surgical procedures including enucleation of the right globe and exploratory abdominal laparotomy to stop internal bleeding. Currently, he states that he has noticed decreased vision in his left eye. The patient has a past medical history of poorly controlled diabetes, asthma, and atopic dermatitis. His temperature is 98.9°F (37.2°C), blood pressure is 167/108 mmHg, pulse is 90/min, respirations are 14/min, and oxygen saturation is 97% on room air. Physical exam is notable for 20/200 vision in the patient's left eye, which is worse than usual. The patient's left eye appears red and irritated. Which of the following is the most likely diagnosis?", "answer": "Sympathetic ophthalmia", "options": {"A": "Anterior uveitis", "B": "Diabetic retinopathy", "C": "Normal post-operative visual adaptations", "D": "Seasonal allergies", "E": "Sympathetic ophthalmia"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 26-year-old female presents to her primary care physician with several months of mood swings, which she feels are affecting her work and personal relationships. She states that on roughly a quarter of days each month, she feels highly irritable, sensitive to criticism and rejection, and easily saddened. She also feels that her appetite varies greatly, and on the days when she is particularly emotional, she also feels especially hungry. As a result of these symptoms, her performance at work has suffered, and her boyfriend has been complaining that she is difficult to live with. She is anxious that she cannot “get my mood under control.” The patient has no past medical history, regular periods every 28 days, and no obstetric history. She uses condoms for contraception. Her mother has major depressive disorder, and her father has hypertension and coronary artery disease. At this visit, the patient’s temperature is 98.4°F (36.9°C), pulse is 75/min, blood pressure is 130/76 mmHg, and respirations are 13/min. She appears slightly anxious but has overall normal affect and is pleasantly conversational. Physical exam is unremarkable. Which of the following is the best next step in management?", "answer": "Selective serotonin reuptake inhibitor", "options": {"A": "Reassurance", "B": "Selective serotonin reuptake inhibitor", "C": "Combined oral contraceptive therapy", "D": "Serotonin-norepinephrine reuptake inhibitor", "E": "Cognitive behavioral therapy"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 63-year-old male presents to the emergency department complaining of worsening nausea. He reports that the nausea began several months ago and is accompanied by occasional bloating and heartburn. He reports that he frequently feels full even after eating only a little at each meal, and occasionally he will vomit if he eats too much. The vomit is non-bloody and contains bits of undigested food. A review of systems is notable for occasional headaches, tingling in his distal extremities, and constipation. His medical history is significant for Parkinson’s disease diagnosed 3 years ago, hypertension diagnosed 8 years ago, and type II diabetes mellitus diagnosed 10 years ago. The patient reports that he was given prescriptions for both his blood pressure and diabetes medications, but he has not taken either for months because one of them was causing erectile dysfunction. He reports he regularly takes his levodopa. An endoscopy is performed, which rules out cancer. In addition to restarting medications for his hypertension and diabetes, what of the following is most appropriate treatment for the patient’s symptoms?", "answer": "Erythromycin", "options": {"A": "Ondansetron", "B": "Metoclopramide", "C": "Scopolamine", "D": "Proton-pump inhibitor", "E": "Erythromycin"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 27-year-old Japanese man presents to the emergency department with diarrhea. The patient states that whenever he goes out to eat he experiences bloating, flatulence, abdominal cramps, and watery diarrhea. Today, his symptoms started after he went out for frozen yogurt. The patient is otherwise healthy and is not currently taking any medications. His temperature is 98.0°F (36.7°C), blood pressure is 122/80 mmHg, pulse is 81/min, respirations are 13/min, and oxygen saturation is 99% on room air. Physical exam demonstrates a nontender abdomen and an unremarkable rectal exam with guaiac-negative stools. Which of the following is the most appropriate next step in management?", "answer": "Lactose-free diet", "options": {"A": "Colonoscopy", "B": "Hydrogen breath test", "C": "Lactose-free diet", "D": "Loperamide", "E": "Stool osmotic gap"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 29-year-old woman presents to her primary care physician with worsening fatigue and lightheadedness over the past several months. She states that she has felt easily fatigued and has experienced several falls during this time frame as well. She drinks 5 to 8 drinks per day and works as a waitress. Her temperature is 98.2°F (36.8°C), blood pressure is 114/64 mmHg, pulse is 98/min, respirations are 12/min, and oxygen saturation is 98% on room air. Laboratory studies are ordered as seen below.\n\nHemoglobin: 9.0 g/dL\nHematocrit: 29%\nLeukocyte count: 6,700/mm^3 with normal differential\nPlatelet count: 199,400/mm^3\nMethylymalonic acid: 1.0 umol/L (normal < 0.40 umol/L)\n\nWhich of the following is the most likely etiology of this patient's symptoms?", "answer": "Vitamin B12 deficiency", "options": {"A": "Alcohol use", "B": "Folate deficiency", "C": "Hypothyroidism", "D": "Iron deficiency", "E": "Vitamin B12 deficiency"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 32-year-old man from the Czech Republic is brought to the emergency department by his girlfriend with a 2-day history of yellowing of the skin. His girlfriend also reports a several-week history of anorexia, nausea without vomiting, and diffuse low-grade abdominal pain. He is a frequent injection drug user. His temperature is 38.1°C (100.6°F). He is grossly confused and somnolent. Physical examination is notable for scleral icterus and diffuse jaundice; when asked to hold his hands in wrist extension, a flapping movement is observed. Liver function tests show alanine aminotransferase 1,830 U/L, aspartate aminotransferase 1,377 U/L, and direct bilirubin 15 mg/dL. Coagulation studies reveal an international normalized ratio of 3.8. On serological testing, HBsAg is positive, and HBsAb is negative. Which of the following laboratory tests should be performed in this patient prior to initiating treatment?", "answer": "Hepatitis D serologies", "options": {"A": "Hepatitis C serologies", "B": "Hepatitis D serologies", "C": "HIV ELISA", "D": "PPD skin test", "E": "Lumbar puncture"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 63-year-old woman with a history of adult polycystic kidney disease and COPD presents to her optometrist after having difficulty watching a movie. She has no other complaints. She is accompanied by her daughter, who notes that her mother hasn’t been able to look at her since the previous day. On exam, her right eye has full range of motion, but her left eye is fixed in a down and outward position. What is the most likely cause of her symptoms?", "answer": "Vascular abnormality", "options": {"A": "Brainstem tumor", "B": "Vascular abnormality", "C": "Seizure", "D": "Demyelinating disease", "E": "Impaired dopaminergic neurons"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "An 11-year-old boy presents to the office with his mother for the evaluation of weight loss, rash, and several weeks of bloating and diarrhea. The mother states that the patient’s father had similar symptoms at his age. On physical examination, the patient is pale with dry mucous membranes. There is a vesicular rash on the bilateral lower extremities which he says is ‘very itchy’. Which of the following laboratory findings would confirm the most likely diagnosis in this patient?", "answer": "Anti-tTG or gliadin antibodies", "options": {"A": "Anti-histone antibodies", "B": "HLA-DQ2", "C": "Anti-tTG or gliadin antibodies", "D": "Anti-lactase antibodies", "E": "HLA-B27"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 23-year-old African American G1P0 woman at 18 weeks estimated gestational age presents with fatigue and lethargy. She says the symptoms onset gradually about 1 week ago and have progressively worsened. She has been otherwise healthy. Past medical history is unremarkable. She denies smoking, drug or alcohol use. The patient is afebrile and vital signs are within normal limits. Her physical examination is unremarkable. Her blood count shows the following:\nHemoglobin 10.8 g/dL\nRed blood cell count 5.7 million/mm3\nMean corpuscular volume (MCV) 76 μm3\nRed cell distribution width 12.4% (ref: 11.5–14.5%)\nShe is empirically started on ferrous gluconate tablets. Five weeks later, she shows no improvement in her hemoglobin level. Hemoglobin electrophoresis is normal. Which of the following is the most likely diagnosis in this patient?", "answer": "Alpha-thalassemia trait", "options": {"A": "Iron deficiency anemia", "B": "Beta-thalassemia trait", "C": "Alpha-thalassemia trait", "D": "Folate deficiency anemia", "E": "Pure red cell aplasia"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 26-year-old woman comes to the physician for a follow-up examination 1 week after undergoing rotator cuff repair surgery. Physical examination of the right shoulder shows decreased sensation to pinprick and light touch over the lateral shoulder. There is normal passive range of motion of the shoulder, but she has difficulty externally rotating and abducting her right arm. Which of the following structures was most likely injured during the surgery?", "answer": "Axillary nerve", "options": {"A": "Radial nerve", "B": "Upper trunk of the brachial plexus", "C": "Axillary nerve", "D": "Lower trunk of the brachial plexus", "E": "Long thoracic nerve"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 25-year-old man presents to his primary care physician with complaints of coughing up blood in his sputum and dark-colored urine for 1 week. There are streaks of blood intermixed with phlegm. He also expresses concerns about his urine being grossly dark brown. He denies any history of major bleeding from minor injuries. He is currently not taking any medications. His family history is negative for bleeding disorders. The vital signs include blood pressure 160/100 mm Hg, pulse 88/min, temperature 36.8°C (98.2°F), and respiratory rate 11/min. On physical examination, there are no significant clinical findings. The urinalysis results are as follows:\npH 6.7\nColor dark brown\nRed blood cell (RBC) count 12–14/HPF\nWhite blood cell (WBC) count 3–4/HPF\nProtein absent\nCast RBC and granular casts\nGlucose absent\nCrystal none\nKetone absent\nNitrite absent \n24 hours of urine protein excretion 1 g\n    His renal function test showed:\nSodium 136 mEq/L\nPotassium 5.1 mEq/L\nChloride 101 mEq/L\nBicarbonate 22 mEq/L\nAlbumin 3.5 mg/ dL\nUrea nitrogen 28 mg/dL\nCreatinine 2.5 mg/dL\nUric Acid 6.8 mg/ dL\nCalcium 8.7 mg/ dL\nGlucose 111 mg/dL\nHPF: high-power field\nA kidney biopsy is obtained and the immunofluorescence shows linear immunoglobulin G (IgG) deposition in the glomeruli. Which of the following antibodies is most likely responsible for this patient’s condition?", "answer": "Anti-glomerular basement membrane antibody (anti-GBM)", "options": {"A": "Anti-neutrophil cytoplasmic antibody (c-ANCA)", "B": "Anti-phospholipid antibody", "C": "Anti-neutrophil perinuclear antibody (p-ANCA)", "D": "Anti-glomerular basement membrane antibody (anti-GBM)", "E": "Anti-dsDNA antibody"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "The lung of a 45-year-old Caucasian male who died from Mycobacterium tuberculosis infection reveals the following at autopsy (Image A). Of the steps leading to the formation of this structure, which occurs first?", "answer": "Bacterium-mediated inhibition of phagosome-lysosome fusion", "options": {"A": "Activation of macrophages by T-lymphocytes", "B": "Th1 cell activation", "C": "Bacterium-mediated inhibition of phagosome-lysosome fusion", "D": "Formation of epithelioid cells", "E": "Formation of giant cells"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 57-year-old man comes to the physician because of a 3-month history of bloating and nausea after eating food. He has also had episodic abdominal pain during this period. He has osteoarthritis of the left knee. There is no family history of serious illness. He has smoked one pack of cigarettes daily for 21 years. He drinks two to three beers daily. Current medications include ibuprofen. He is allergic to amoxicillin and latex. Vital signs are within normal limits. The lungs are clear to auscultation. Cardiac examination shows no abnormalities. The abdomen is soft; there is mild tenderness to palpation over the epigastrium. Rectal examination shows no abnormalities. An esophagogastroduodenoscopy is performed and shows 3 shallow ulcers of the gastric mucosa. Biopsy shows chronic inflammation of the gastric mucosa and Helicobacter pylori. He is prescribed a 2-week course of antibiotics and omeprazole to treat the H. pylori infection. Which of the following recommendations is most appropriate at this time?", "answer": "Avoid drinking alcohol for the next 2 weeks", "options": {"A": "Avoid drinking alcohol for the next 2 weeks", "B": "Return for repeat endoscopy in 2 weeks", "C": "Begin prophylactic steroid therapy for anaphylaxis", "D": "Check liver enzymes in 2 weeks", "E": "Perform urea breath test in 2 weeks"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 72-year-old man presents to his physician’s office with difficulty breathing and chronic fatigue. Over the past few months, he has felt that it is difficult to retain his energy throughout the day. He is disturbed because he has to skip many social events because of his inability to participate. He also says that lately, he has had difficulty catching his breath after walking for just a few blocks. Other than well-controlled diabetes, his past medical history is insignificant. On physical examination, moderate conjunctival pallor is noted. His recent blood count shows a hemoglobin level of 10.3 g/dl, hematocrit of 24%, serum ferritin level of 10 ng/ml, and a red cell distribution width of 16.5%. Which of the following would be the best next step in the management of this patient?", "answer": "Colonoscopy", "options": {"A": "Colonoscopy", "B": "Ultrasound", "C": "Vitamin B12 levels", "D": "Endoscopy", "E": "Iron supplementation"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 17-year-old rugby player limped into the emergency room and says he “rolled his ankle” while running during a game. You conclude that the mechanism involved ankle plantar flexion and inversion. There is no medial or lateral malleolus point tenderness. Anterior drawer test of the ankle is positive. Talar tilt test is negative. What is the most likely injury?", "answer": "Anterior talofibular ligament (ATFL) sprain", "options": {"A": "Anterior talofibular ligament (ATFL) sprain", "B": "Calcaneofibular ligament (CFL) sprain", "C": "Deltoid ligament sprain", "D": "Tibia fracture", "E": "Fibula fracture"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "Which of the following statements concerning positive predictive value (PPV) is correct?", "answer": "PPV is the proportion of tests that are true positives; if disease prevalence is low, then PPV will be low.", "options": {"A": "PPV is the proportion of tests that are true positives; if disease prevalence is low, then PPV will be low.", "B": "PPV is the proportion of tests that are true positives; if disease prevalence is high, then PPV will be low.", "C": "PPV is the proportion of tests that are true positives; disease prevalence has no effect on PPV.", "D": "PPV is the proportion of tests that are false positives; if disease prevalence is low, then PPV will be low.", "E": "PPV is the proportion of tests that are false positives; if disease prevalence is high then PPV will be low."}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 32-year-old man presents to the emergency department with fever, weight loss, and right upper quadrant pain. He says that he started experiencing nausea and fatigue after he returned from a honeymoon trip to Asia with his wife. Notably, she is 5 months pregnant with their first child. On presentation, his temperature is 100.8°F (38.2°C), blood pressure is 118/79 mmHg, pulse is 81/min, and respirations are 14/min. Physical exam reveals a jaundiced patient with a palpable liver edge as well as splenomegaly. Labs are sent in order to confirm the diagnosis. After confirmation, the patient's wife is immediately tested as well because she is at a much higher risk of fatal complications from this infection. The organism that is most likely responsible for this patient's symptoms has which of the following structures?", "answer": "Non-enveloped (+) RNA hepevirus", "options": {"A": "Enveloped dsDNA virus", "B": "Enveloped (-) RNA virus", "C": "Enveloped (+) RNA virus", "D": "Non-enveloped (+) RNA hepevirus", "E": "Non-enveloped (+) RNA picornavirus"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 59-year-old man presents to the emergency room with shortness of breath and swelling of his feet and legs. He denies any past medical problems, surgeries, medications, or illicit drug use. He reports drinking a few beers each night. He is diagnosed with a first episode of congestive heart failure and is admitted to the hospital. The next day, the nurse notices that his hands are shaky when he extends his arms. The patient says that he couldn’t sleep the night before and that he feels restless, anxious, and slightly nauseated. On the second night of admission the patient becomes agitated. He is disoriented, cannot remember where he is, and appears globally confused. His pulse is 125/min, blood pressure is 170/110 mmHg, and temperature is 101.7°F (38.7°C). He is diaphoretic and his hands are shaking at rest. He cries out in fear reporting voices whispering in his room and strange shadows passing over the walls. What medication should be administered to this patient?", "answer": "Benzodiazepines", "options": {"A": "Flumazenil", "B": "Naloxone", "C": "Benzodiazepines", "D": "Dantrolene", "E": "Fomepizole"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 49-year-old woman otherwise healthy presents to the outpatient department with swelling of the neck. Family history is negative for any thyroid disorders. Physical examination shows a nontender thyroid gland with a nodule on the right side. The thyroid gland is mobile on deglutition. Cervical lymphadenopathy is present. Fine needle aspiration and cytology show empty appearing nuclei with central clearing, nuclear grooves and branching structures interspersed with calcific bodies. Which of the following is the most likely diagnosis in this patient?", "answer": "Papillary carcinoma", "options": {"A": "Follicular carcinoma", "B": "Papillary carcinoma", "C": "Medullary carcinoma", "D": "Anaplastic carcinoma", "E": "Follicular adenoma"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 33-year-old woman comes to the physician because of a 2-year history of intermittent episodes of pain in all her fingers bilaterally. The episodes are worse during the winter. The fingers become white when exposed to cold weather, then severely painful and numb once they warm up. She has started wearing gloves at all times to prevent these episodes. She has generalized anxiety disorder. Her mother has systemic lupus erythematosus. Current medications include lorazepam and fluoxetine. She appears anxious. Her temperature is 37.3°C (99.1°F), pulse is 92/min, and blood pressure is 116/72 mm Hg. Examination of both hands shows no abnormalities. Allen's test is negative. Her hemoglobin concentration is 14.4 g/dL, leukocyte count is 9,800/mm3, and platelet count is 156,000/mm3. Serum electrolyte concentrations are within normal limits. Nailfold capillary microscopy is normal. Which of the following is the most appropriate pharmacotherapy?", "answer": "Oral nifedipine", "options": {"A": "Oral aspirin", "B": "Topical nitroglycerin", "C": "Oral nifedipine", "D": "Oral epoprostenol", "E": "Oral prednisone"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 43-year-old man comes to the physician because of redness and swelling of his right leg. He reports that it is very painful to touch. He has had fever and chills. He has no chest pain or shortness of breath. He has a history of type 2 diabetes mellitus and underwent saphenous vein stripping and ligation in his right leg 3 years ago. He works as a security guard. He does not smoke or drink alcohol. His medications include metformin and sitagliptin. His temperature is 38.7°C (101.7°F), pulse is 99/min, and blood pressure is 138/72 mm Hg. Examination shows an 8-cm, indurated, tender, warm, erythematous skin lesion with sharply demarcated margins. There is no inguinal lymphadenopathy. Toe web intertrigo is noted. Which of the following is the most appropriate next step in management?", "answer": "Intravenous cefazolin therapy", "options": {"A": "Oral cephalexin therapy", "B": "Intravenous cefazolin therapy", "C": "Symptomatic relief only", "D": "Intravenous ciprofloxacin therapy", "E": "Subcutaneous heparin injection"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 52-year-old thoracic surgeon presents to his primary care physician with an eczematous dermatitis overlying his hands and forearms. He notes that he has recently started using a new type of surgical gloves. He notes that he washes his hands frequently, but he has never had issues with skin irritation before. On physical examination, there are erythematous plaques with areas of vesicles on his bilateral hands and dorsal forearms. Of the following options, which is the next best step in patient management?", "answer": "Patch testing", "options": {"A": "Bacterial culture", "B": "Patch testing", "C": "KOH examination", "D": "Skin biopsy", "E": "Radioallergosorbent test"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 43-year-old woman presents to a new primary care physician complaining of anxiety. She has been worrying non-stop recently about the possibility that her husband will lose his job as a teacher. Her husband, who is present, assures the physician that his job is entirely secure and states that she has \"fretted\" for their entire marriage, though the exact topic causing her anxiety varies over time. She also worries excessively about everyday tasks, such as whether she will catch the train on time and whether their house in Southern California is sufficiently earthquake-proof. She has no way to overcome these worries. She endorses other symptoms including poor sleep (associated with racing thoughts about her various worries), fatigue, and impaired concentration at work, all of which have been present for at least the past year. Her vital signs are within normal limits and there are no abnormalities on physical exam. What is the most likely diagnosis?", "answer": "Generalized anxiety disorder", "options": {"A": "Acute stress disorder", "B": "Social phobia", "C": "Agoraphobia", "D": "Posttraumatic stress disorder", "E": "Generalized anxiety disorder"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 60-year-old woman comes to the physician because of palpitations and a 5.4-kg (11.9-lb) weight loss over the past 3 months. She appears anxious. Her pulse is 104/min and blood pressure is 148/101 mm Hg. Physical examination shows warm skin, mild tremor, and an enlarged thyroid gland. A thyroid scintigraphy scan shows several focal areas with increased uptake. A biopsy of one of these areas of affected thyroid tissue is most likely to show which of the following?", "answer": "Patches of enlarged follicular cells distended with colloid", "options": {"A": "Sheets of parafollicular cells surrounded by amyloid stroma", "B": "Inflammatory infiltrate with multinucleated giant cells and granuloma formation", "C": "Follicle destruction with lymphocytic infiltrate and germinal center formation", "D": "Patches of enlarged follicular cells distended with colloid", "E": "Crowded follicular cells with scalloped colloid"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 47-year-old man is brought to the emergency department 1 hour after his neighbor found him collapsed on his front porch in a pool of vomitus. On arrival, he is oriented only to self. His pulse is 103/min and respirations are 30/min. Neurologic examination shows muscle spasms in the arms and jaw. Serum studies show:\nNa+ 137 mEq/L\nCl- 99 mEq/L\nHCO3- 8 mEq/L\nOsmolality 328 mOsm/kg\nThe difference between the calculated and observed serum osmolality is 32 mOsm/kg. Urinalysis shows oxalate crystals. This patient is most likely experiencing toxicity from which of the following substances?\"", "answer": "Ethylene glycol", "options": {"A": "Methanol", "B": "Ethylene glycol", "C": "Parathion", "D": "Isopropyl alcohol", "E": "Aspirin"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 13-year-old boy presents to the clinic for evaluation of pain, swelling, and redness in the left knee. This began a month ago and has been progressively worsening. He thinks his pain is due to playing soccer. He is frustrated that the pain does not respond to Tylenol. History is non-contributory. The vital signs are unremarkable. On examination, there is tenderness and warmth present over the knee with limitation of movement. The laboratory values show a normal white blood cell (WBC) count and elevated alkaline phosphatase. A radiograph of the knee shows mixed lytic and blastic lesions. Which of the following is the most probable cause of his complaints?", "answer": "Osteosarcoma", "options": {"A": "Osteomyelitis", "B": "Osteosarcoma", "C": "Ewing’s sarcoma", "D": "Histiocytosis", "E": "Chondrosarcoma"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 55-year-old woman presents to the emergency department because of palpitations and generalized weakness. She has a history of type 2 diabetes, for which she has been receiving medication for the past 15 years. Consequently, her recent medical history involves diabetic retinopathy as well as end-stage renal disease. She is advised dialysis; however, she does not attend her regular dialysis sessions. The physical examination shows motor strength of 3/5 in the upper limbs and 4/5 in the lower limbs. Cranial nerve capacity is intact. Her electrocardiogram (ECG) is shown. Medical management is initiated for the patient. Which of the following is the most likely explanation for this patient’s clinical findings?", "answer": "Skipped dialysis appointment", "options": {"A": "Skipped dialysis appointment", "B": "Hyperglycemia", "C": "Insulin supplementation", "D": "Administration of α-agonist", "E": "Alkalosis"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 59-year-old man presents to the emergency department with diffuse abdominal pain that radiates to his back, nausea, and vomiting. The vital signs include: temperature 36.7°C (98.0°F), blood pressure 126/74 mm Hg, heart rate 74/min, and respiratory rate 14/min. The laboratory evaluation on admission is significant for a serum glucose 241 mg/dL, aspartate aminotransferase (AST) 321 IU/dL, and leukocyte count 21,200/mL. Within 3 days of admission with supportive care in the intensive care unit, the patient’s clinical condition begins to improve. Based on Ranson’s Criteria, what is this patient’s overall risk of mortality, assuming all other relevant factors are negative?", "answer": "20%", "options": {"A": "< 10%", "B": "20%", "C": "40%", "D": "80%", "E": "100%"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 68-year-old male presents to your office for his annual physical exam. He has no complaints at this time and his chronic hypertension is well controlled. You notice a .5cm papule on the patient's eyelid that has a pink pearly appearance, rolled borders, and overlying telangiectasias. On further questioning, you find out the patient was a door-to-door salesman and spent a lot of time outdoors, and he did not wear sunscreen. He has fair skin and blonde hair. The patient states that he first noticed the lesion about 6 months prior, and it has grown slightly since then. What is the most likely diagnosis?", "answer": "Basal cell carcinoma", "options": {"A": "Squamous cell carcinoma", "B": "Keratoacanthoma", "C": "Verrucous carcinoma", "D": "Basal cell carcinoma", "E": "Actinic keratosis"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 67-year-old woman is brought to the emergency room after complaining of back pain with a gradual loss of sensation in her lower extremities. She was recently diagnosed with radiosensitive metastatic breast cancer and was scheduled to receive chemotherapy and palliative surgery. Her temperature is 99.0°F (37.2°C), blood pressure is 133/81 mmHg, pulse is 82/min, respirations are 15/min, and oxygen saturation is 98% on room air. Physical exam is notable for decreased sensation bilaterally over the patient's lower extremities. She demonstrates 2/5 strength of leg extension on the left and 1/5 on the right which is slightly worse than her baseline neurological exam taken 2 months ago. Pain to her lumbar region worsens with coughing. An initial CT scan of the spine does not demonstrate any unstable fractures of the spine. A MRI of the spine is ordered and pending. Which of the following is the most appropriate next step in management?", "answer": "Radiation therapy", "options": {"A": "Biopsy", "B": "Chemotherapy", "C": "Palliative pain management", "D": "Radiation therapy", "E": "Surgical decompression"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "An obese 50-year-old woman presents to the emergency department of a rural hospital due to chest pain for the last 12 hours. The pain is substernal, crushing in nature, radiating into her neck, and accompanied by profuse sweating. Her history is significant for hypertension, and she admits poor compliance with her medications. An ECG done at the clinic confirmed the presence of STEMI, and the patient was given aspirin. The ambulance was in an accident on the way to the hospital and by the time the patient reached the angiography suite, the cardiologist decided intervention should be delayed due to the late presentation. Also, the patient’s pain has improved. The patient is admitted and is stable for 3 nights with no dyspnea or edema. Her blood pressure is kept under control while in the hospital. On the fourth night, the patient becomes quite agitated and soon thereafter she is unresponsive. Her pulse cannot be palpated. She has an elevated JVP and upon auscultation, heart sounds are distant. What is the most likely diagnosis for this patient?", "answer": "Left ventricular free wall rupture", "options": {"A": "Acute pericarditis", "B": "Ventricular septal rupture", "C": "Left ventricular free wall rupture", "D": "Papillary muscle rupture", "E": "Pulmonary embolism"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 20-year-old woman presents to the emergency department with painful swelling in the middle of her neck for the past 3 days. She is not experiencing pain during swallowing, difficulty in breathing, or changes in her voice. On examination, a red, 5 x 5 cm, exquisitely tender, non-pulsatile, fluctuating mass is present in the midline on the anterior aspect of the neck. The patient is prepared for an incision and drainage of the neck abscess. Which of the following is responsible for the exact mechanism of diapedesis that allows for inflammatory cells to enter the tissue space of this patient?", "answer": "Transmigration and chemotaxis", "options": {"A": "Phagocytosis", "B": "Adhesion", "C": "Margination", "D": "Transmigration and chemotaxis", "E": "Rolling"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 45-year-old G2P2 presents with episodes of urgency accompanied by an involuntary passage of urine. These symptoms take place during the day and night. The symptoms are not linked with physical exertion, laughing, or coughing. Her occupation does not involve weight lifting, but she says that sometimes it is very stressful for her. She denies any other genitourinary symptoms. She had  1 vaginal delivery and 1 cesarean section. She does not have a history of genitourinary or neurologic disorders. The weight is 91 kg (200.6 lb) and the height is 172 cm (5 ft 60 in). The vital signs are as follows: blood pressure, 128/75 mmHg; heart rate, 77/min; respiratory rate, 13/min; and temperature, 36.6℃ (97.9℉). The physical examination shows no abdominal masses and no costovertebral angle or suprapubic tenderness. On gynecologic examination, there are no vulvar lesions. The external urethral orifice appears normal. A Q-tip test is negative. The cervix is normally positioned, non-tender, movable, and without visible lesions. The uterus is not enlarged and the ovaries are not palpable. A urinalysis, urine culture, and ultrasound examination of the bladder were all normal. Cystometric studies show the following findings:\n  Measured value Normal range\nResidual volume 10 ml < 50 ml\nSensation-of-fullness volume 190 ml 200–225 ml\nUrge-to-void volume 700 ml 400–500 ml\nInvoluntary contractions present absent\nWhich of the following treatment strategies would be most appropriate for this patient?", "answer": "Start her on a muscarinic antagonist", "options": {"A": "Instillation of the urethral mesh sling", "B": "Topical estrogen therapy", "C": "Augmentation cystoplasty", "D": "Sacral nerve stimulation", "E": "Start her on a muscarinic antagonist"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 4-year-old girl is brought to the physician with progressively worsening fever, malaise, and a sore throat. Her parents say “Our daughter has not received vaccinations because her body has to learn how to fight infections.” Her temperature is 38.5˚C (101.3 F). Physical examination shows marked cervical lymphadenopathy. There are gray-white membranes over the tonsils and posterior pharynx that bleed when scraped off. The patient's symptoms are most likely caused by disruption of which of the following steps in protein synthesis?", "answer": "Translocation of the ribosome along the mRNA", "options": {"A": "Folding of completed proteins", "B": "Translocation of the ribosome along the mRNA", "C": "Binding of tRNA to the A site", "D": "Interference of post-translational modifications", "E": "Release of completed protein from ribosome"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 56-year-old man presents to his family physician for issues with his back that have persisted since he was in his 20’s. For the last 6 months, his neck has been very stiff and he has been unable to tilt his head backwards. He also has severe kyphosis and feels limited in his range of motion. He tries to get at least 8 hours of sleep each night, but he says he rarely feels rested. On examination, the patient has no pain on active and passive movements. His cervical spine is moderately stiff; limitations are in extension, flexion, and rotation. There is also evidence of mild swelling of his wrist joints. The patient is sent for an X-ray of his lumbar spine. Unfortunately, he did not seek medical care for years due to financial hardships. Which of the following therapies would have been first line for improving this patient’s symptoms early in the course of this disease?", "answer": "Indomethacin", "options": {"A": "Infliximab", "B": "Indomethacin", "C": "Ceftriaxone", "D": "Methotrexate", "E": "Sulfasalazine"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 24-year-old woman visits the health services of her university for vaginal itching, dysuria, pelvic discomfort, and foul-smelling vaginal discharge. She states this is the eighth time she has had such symptoms within the last year, for which she and her sexual partners have received multiple courses of doxycycline and ceftriaxone or azithromycin and ceftriaxone. A pelvic examination showed a mucopurulent cervical discharge with cervical friability. A vaginal wet-mount showed an elevated number of polymorphonuclear leukocytes. What is the most likely cause of this patient’s cervicitis?", "answer": "Mycoplasma genitalium", "options": {"A": "Chlamydia trachomatis", "B": "Streptococcus agalactiae", "C": "Mycoplasma hominis", "D": "Mycoplasma genitalium", "E": "Neisseria gonorrhoeae"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A previously healthy 11-month-old boy is brought to the emergency department for the evaluation of abdominal pain and vomiting. His mother states that over the past 6 hours he has been having intermittent episodes of inconsolable crying, during which he “grabs his abdomen and draws up his legs.” These episodes have been accompanied by nonbloody, nonbilious vomiting and reddish, mucoid bowel movements. He appears sleepy. His temperature is 38.1°C (100.6°F), blood pressure 100/60 mm Hg, pulse is 110/min, and respirations are 24/min. He cries when his abdomen is palpated. The remainder of the examination shows no abnormalities. A complete blood count shows a leukocyte count of 12,000/mm3. Serum electrolyte levels are within normal limits. An abdominal x-ray shows no free air. An abdominal ultrasonography is shown. Which of the following is the most appropriate next step in management?", "answer": "Air enema", "options": {"A": "Air enema", "B": "Appendectomy", "C": "Technetium-99m pertechnetate scan", "D": "Pyloromyotomy", "E": "Therapy with ampicillin, tobramycin, and metronidazole"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 68-year-old man comes to the physician because of a 4-month history of bad breath and progressive difficulty swallowing solid food. Physical examination shows no abnormalities. An upper endoscopy is performed and a photomicrograph of a biopsy specimen obtained from the mid-esophagus is shown. Which of the following best explains the findings in this patient?", "answer": "Neoplastic proliferation of squamous epithelium", "options": {"A": "Well-differentiated neoplastic glandular proliferation", "B": "Atrophy and fibrosis of the esophageal smooth muscle", "C": "Metaplastic transformation of esophageal mucosa", "D": "Neoplastic proliferation of squamous epithelium", "E": "Eosinophilic infiltration of the esophageal walls\n\""}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 43-year-old woman comes to the physician because of a 2-month history of progressive muscle pain and stiffness that worsens with exercise. She also has difficulty climbing stairs, getting out of chairs, and putting things on shelves or in cupboards. She has had constipation, occasional headaches, and a 9-kg (20-lb) weight gain during the past year. She has hypertension controlled with atenolol and amlodipine. She has used calamine lotion for the past 6 months for dry skin. Her pulse is 80/min and her blood pressure is 138/76 mm Hg. Physical examination shows weakness of the proximal muscle groups. She has delayed tendon reflex relaxation, with a mounding of the muscle surface occurring just before relaxation. Creatine kinase level is 3,120 U/L. Which of the following is the most appropriate next step in diagnosis?", "answer": "Serum TSH levels", "options": {"A": "Serum TSH levels", "B": "Acetylcholine receptor antibody testing", "C": "Serum potassium levels", "D": "Anti-voltage-gated calcium channel antibody testing", "E": "Temporal artery biopsy"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 34-year-old woman comes to the physician because of a rapidly growing lump in her right breast. Eight months ago, she underwent excision of a liposarcoma from the dorsum of her right forearm. Her brother was diagnosed with osteosarcoma of the maxilla at the age of 22 years. Her mother died at the age of 43 years from complications of acute myeloid leukemia. She has smoked a pack of cigarettes daily for 7 years. Examination shows a fixed, firm mass in the right breast with axillary lymphadenopathy. A biopsy of the mass confirms the diagnosis of invasive ductal carcinoma. Which of the following genetic principles is most likely responsible for this patient's condition?", "answer": "Loss of heterozygosity in tumor suppressor gene", "options": {"A": "Loss of heterozygosity in tumor suppressor gene", "B": "Methylation of a previously normal gene copy", "C": "Oncogenic transformation of a previously normal gene", "D": "Chronic exposure to carcinogenic material", "E": "Exposure to an oncogenic microbial infection"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 31-year-old woman comes to the doctor because of episodic nosebleeds and gingival bleeding for the past 2 weeks. She has no history of serious illness and takes no medications. She is sexually active with two male partners and uses condoms inconsistently. Vital signs are within normal limits. Examination shows punctate, non-blanching macules on the chest. The remainder of the examination shows no abnormalities. The hemoglobin concentration is 13.1 g/dL, leukocyte count is 6600/mm3, and platelet count is 28,000/mm3. A peripheral blood smear shows reduced platelets with normal morphology. HIV test is negative. Which of the following is the most appropriate next step in management?", "answer": "Hepatitis C antibody testing", "options": {"A": "Blood cultures", "B": "D-dimer testing", "C": "Hepatitis C antibody testing", "D": "Anti-platelet antibody testing", "E": "Platelet aggregation testing"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 40-year-old woman presents to the clinic for hair loss. She was in her usual state of health until earlier this month when she started noticing more and more hair on her pillow in the morning. The problem has only been getting worse since then; she's even started pulling out clumps of hair when she shampoos in the morning. She has no other symptoms, and her past medical history is unremarkable. The physical exam is notable for smooth, circular, non-scarring, hairless patches across her scalp. A firm tug on a bundle of hair causes almost all of the hair to be removed. Which of the following is the most likely diagnosis?", "answer": "Alopecia areata", "options": {"A": "Alopecia areata", "B": "Discoid lupus erythematosus (DLE)", "C": "Secondary syphilis", "D": "Tinea capitis", "E": "Trichotillomania"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 2-day-old girl born at 32 weeks gestation to a 42-year-old woman is being examined by a resident. The examination reveals a very small head circumference with low set ears, a prominent occiput, and a comparatively small mandible. A picture of the infant’s fist is given below. A bilateral foot deformity is present. Which of the following is the most likely karyotype abnormality in this infant?", "answer": "Trisomy 18", "options": {"A": "47, XXX", "B": "Trisomy 13", "C": "Trisomy 21", "D": "Trisomy 18", "E": "47, XXY"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 44-year-old male is brought to the physician by his father. Over the past year, the patient has become progressively forgetful and withdrawn. He frequently has trouble remembering names of acquaintances, and has been requiring increasing amounts of assistance with getting dressed, cooking, and personal hygiene. He was diagnosed with a genetic disorder during infancy. Physical examination shows prominent epicanthal folds, low-set small ears, and a protruding tongue. Mental examination shows significant deficits in short- and long-term memory. This patient's cognitive symptoms are most likely the result of which of the following neuropathologic changes?", "answer": "Extracellular accumulation of amyloid plaques", "options": {"A": "Intracellular aggregations of alpha-synuclein", "B": "Multifocal deposition of excess copper", "C": "Synaptic build-up of abnormal prion protein", "D": "Cytoplasmic inclusions of ubiquinated TDP-43", "E": "Extracellular accumulation of amyloid plaques"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A previously healthy 75-year-old man comes to the physician with a 6-month history of fatigue, weight loss, and abdominal pain. He drinks 2 oz of alcohol on the weekends and does not smoke. He is retired but previously worked in a factory that produces plastic pipes. Abdominal examination shows right upper quadrant tenderness; the liver edge is palpable 2 cm below the ribs. A liver biopsy specimen shows pleomorphic spindle cells that express PECAM-1 on their surface. Which of the following is the most likely diagnosis?", "answer": "Angiosarcoma", "options": {"A": "Cavernous hemangioma", "B": "Kaposi sarcoma", "C": "Angiosarcoma", "D": "Hepatocellular carcinoma", "E": "Cholangiocarcinoma\n\""}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 28-year-old man is brought to the emergency department 20 minutes after being involved in a bicycling accident. He complains of severe pain over the front of his right shoulder. He refuses to move his right arm. Physical examination shows supraclavicular swelling and bruising. The shoulder's range of motion is limited by pain. An x-ray of the shoulder shows a fracture of the middle third of the clavicle with complete superior displacement of the medial clavicular segment. Which of the following muscles is responsible for the displacement of this segment?", "answer": "Sternocleidomastoid", "options": {"A": "Trapezius", "B": "Deltoid", "C": "Subclavius", "D": "Pectoralis major", "E": "Sternocleidomastoid"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 49-year-old woman presents to her oncologist with progressive difficulty breathing at rest, decreased exercise tolerance, and ankle swelling bilaterally for the past 2 weeks. She was diagnosed with breast cancer 4 years ago which was treated with radical mastectomy, radiation, and aggressive chemotherapy. She does not smoke or drink alcohol. Her family history is positive for breast cancer in her elder sister. Vital signs include: blood pressure 85/50 mm Hg, temperature 36.7°C (98.1°F), and a regular pulse of 110/min. The physician notices that, with inspiration, the radial pulse becomes weak. On physical examination, she looks anxious and tachypneic. Jugular venous pressure is 14 cm and heart sounds are distant. Lungs are clear and 1+ pedal edema is noted. Her chest X-ray is shown in the exhibit. Echocardiography of this patient will most likely show which of the following?", "answer": "Impairment of both early and late diastolic filling with respiratory variation of ventricular filling", "options": {"A": "Rapid early diastolic filling and impaired late diastolic filling", "B": "Impairment of both early and late diastolic filling with respiratory variation of ventricular filling", "C": "Abnormal myocardial texture, and restrictive diastolic dysfunction", "D": "Dilated left and/or right ventricle and low ejection fraction", "E": "Left ventricular hypokinesis, dyskinesis, or akinesis"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 5-year-old boy is brought to the physician because of high-grade fever and generalized fatigue for 5 days. Two days ago, he developed a rash on his trunk. He returned from a family hiking trip to Montana 1 week ago. His immunization records are unavailable. His temperature is 39.8°C (103.6°F), pulse is 111/min, and blood pressure is 96/60 mm Hg. Examination shows injection of the conjunctivae bilaterally. The tongue and pharynx are erythematous. Tender cervical lymphadenopathy is present on the left. There is a macular rash over the trunk and extremities. Bilateral knee joints are swollen and tender; range of motion is limited by pain. Cardiopulmonary examination shows no abnormalities. Which of the following is the most likely diagnosis?", "answer": "Kawasaki disease\n\"", "options": {"A": "Staphylococcal scalded skin syndrome", "B": "Juvenile idiopathic arthritis", "C": "Scarlet fever", "D": "Granulomatosis with polyangiitis", "E": "Kawasaki disease\n\""}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 61-year-old female presents to the emergency room for a headache and vision loss. She reports a 3-hour history of acute-onset dull headache. She also says she cannot see out of part of her eye. Her past medical history is notable for hypertension, hyperlipidemia, and a prior myocardial infarction. She takes enalapril, atorvastatin, aspirin, and metoprolol. On exam, she is alert and oriented to person, place, and time. She has 5/5 strength and full sensation to light touch in her bilateral upper and lower extremities. Her brachioradialis, triceps, patellar, and Achilles reflexes are symmetric and 2+ bilaterally. Fundoscopic examination reveals a normal retina. Visual field examination demonstrates an inability to see in the superior right visual field. This patient’s condition is likely due to a lesion in which of the following locations?", "answer": "Temporal lobe", "options": {"A": "Optic nerve", "B": "Optic tract", "C": "Pituitary gland", "D": "Parietal lobe", "E": "Temporal lobe"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 37-year-old G2P1001 presents to her obstetrician’s office at 31 weeks gestation for decreased fetal movement over the last day. She states that although she occasionally feels some movement, it is decreased from baseline. She denies any gush of fluid, vaginal bleeding, or painful contractions. This pregnancy has been complicated by gestational diabetes for which the patient was prescribed insulin. She reports not always taking postprandial fingersticks; therefore, she infrequently uses her insulin. She also had a urinary tract infection in the first trimester that was successfully treated with nitrofurantoin. The patient has a past medical history of obesity and rosacea, and she had an uncomplicated spontaneous vaginal delivery six years ago. At this visit, the patient’s temperature is 98.6°F (37.0°C), blood pressure is 148/71 mmHg, pulse is 75/min, and respirations are 14/min. The patient appears comfortable and has a fundal height of 33 centimeters. An initial attempt with Doppler ultrasound is unable to detect fetal heart tones. Which of the following is the best next step in management?", "answer": "Non-stress test", "options": {"A": "Non-stress test", "B": "Biophysical profile", "C": "Contraction stress test", "D": "Intravenous labetalol", "E": "Cervical exam"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 59-year-old man is brought to the emergency department by his wife because of fever, chills, night sweats, and generalized fatigue for 2 weeks. His temperature is 39.1°C (102.4°F). He appears ill. Physical examination shows a grade 3/6 mid-diastolic murmur at the left sternal border, and crackles at both lung bases. A transesophageal echocardiography shows a 12 mm vegetation on the aortic valve. Blood cultures show gram-positive, catalase-negative, gamma-hemolytic cocci in chains that are unable to grow in a 6.5% NaCl medium. Which of the following is the most likely predisposing factor for this patient’s current condition?", "answer": "Colon cancer", "options": {"A": "Periodontal disease", "B": "Colon cancer", "C": "Congenital heart defect", "D": "Valve replacement", "E": "Urinary tract infection"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 65-year-old woman presents to her family doctor to reestablish care since her retirement from her corporate job and loss of her employer-sponsored health insurance. She states that she has not had time for regular check-ups. She exercises 3-4 times a week and consumes red meat sparingly. She drank and smoked cigarettes socially with coworkers but never at home or on vacation. She wakes up with achy wrists and elbows that she suspects is from years of using a computer keyboard. She completed menopause at age 52. Her family history is notable for coronary artery disease on her father's side and colon cancer on her mother's side. She last had a colonoscopy 5 years ago that revealed no abnormal findings. Her vital signs are within normal limits and her physical exam is grossly unremarkable. What diagnostic test should this patient receive?", "answer": "Mammography", "options": {"A": "Chest radiograph", "B": "Colonoscopy", "C": "Mammography", "D": "Pelvic ultrasound", "E": "Vitamin D level"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 52-year-old woman comes to the physician because of mild fatigue and dizziness for the past 2 days. She has not been to work since yesterday due to her symptoms. She says she has \"\"very high blood sugar” and has had similar episodes often in the past 2 years, for which she has visited multiple doctors around the city. She has also purchased a home glucose monitoring device, which she uses daily. Since the symptoms began, she has become socially withdrawn and spends much of her time at home researching diabetes on the internet. One week ago, she took a day off work because of her symptoms. She is not on any treatment. She has had 3 laboratory test reports that all show normal fasting and post-meal blood glucose levels. Her father and brother have diabetes mellitus type 2. She appears anxious. Vital signs are normal. Physical examination shows no abnormalities. Random serum glucose is 128 mg/dL. Which of the following is the most likely explanation for this patient's symptoms?\"", "answer": "Illness anxiety disorder", "options": {"A": "Somatic symptom disorder", "B": "Malingering", "C": "Unipolar major depression", "D": "Illness anxiety disorder", "E": "Impaired glucose homeostasis"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 4800 g (10.6 lb) male newborn is delivered at term to a 35-year-old woman, gravida 1, para 1. Significant lateral neck traction is required during delivery. Apgar scores are 9 and 9 at 1 and 5 minutes, respectively. Vital signs are within normal limits. At rest, his right shoulder is adducted and internally rotated. The baby cries with passive movement of the arm. Laboratory studies show:\nHematocrit 66%\nLeukocyte count 9000/mm3\nSerum\nNa+ 142 mEq/L\nCl- 103 mEq/L\nK+ 5.1 mEq/L\nHCO3- 20 mEq/L\nUrea nitrogen 8 mg/dL\nGlucose 34 mg/dL\nCreatinine 0.6 mg/dL\nWhich of the following is most likely to have prevented this infant's condition?\"", "answer": "Administration of insulin", "options": {"A": "Avoidance of soft cheeses", "B": "Administration of insulin", "C": "Abstinence from cocaine", "D": "Avoidance of cat feces", "E": "Vaccination against rubella"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 30-year-old woman comes to the physician for evaluation of successful conception. She and her husband are trying to conceive, and they have had frequent sexual intercourse over the past month. Her menstrual cycles occur at regular 28-day intervals, and her last menstrual period began 25 days ago. Which of the following is the most sensitive test for diagnosing pregnancy at this time?", "answer": "Serum testing", "options": {"A": "Serum testing", "B": "Diagnosis is not yet possible", "C": "Transvaginal ultrasound", "D": "Transabdominal Doppler ultrasound", "E": "Urine testing"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 25-year-old healthy man presents to the physician for an annual checkup. He doesn’t have any concerns and feels completely healthy. He recently started a new job and has been working out at a gym regularly. He does not smoke cigarettes, drinks occasionally, and does not use illicit substances. His vital signs include: pulse 80/min, respirations 14/min, and blood pressure 120/80 mm Hg. Physical examination is significant for a splitting of the second heart sound heard on inspiration but not on expiration. Which of the following is also most likely associated with the auscultatory findings in this patient?", "answer": "Increased right ventricular output", "options": {"A": "Decreased pulmonary blood volume", "B": "Decreased venous return", "C": "Increased intrapleural pressure", "D": "Increased right ventricular output", "E": "Increased systemic blood pressure"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 79-year-old man presents to his primary care physician complaining of progressive shortness of breath on exertion for the past 2 months. He was first aware of having to catch his breath while gardening, and he is now unable to walk up the stairs in his house without stopping. He has had type 2 diabetes mellitus for 30 years, for which he takes metformin and sitagliptin. His blood pressure is 110/50 mm Hg, the temperature is 37.1°C (98.8°F), and the radial pulse is 80/min and regular. On physical examination, there is a loud systolic murmur at the right upper sternal border with radiation to the carotid arteries. Which of the following will increase the intensity of this patient’s murmur?", "answer": "Squatting", "options": {"A": "Squatting", "B": "Standing up from a sitting position", "C": "Diuretics", "D": "Valsalva maneuver", "E": "Volume depletion"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 47-year-old woman presents with intermittent throbbing headaches. She says that she has had at least 1–2 every week for the last 3 months. She describes the pain as severe, pulsatile, and localized to the right frontotemporal and periorbital areas. She says the headaches usually last for several hours and are made worse by the presence of light. She endorses nausea with occasional vomiting during the most severe episodes. She denies any seizures, loss of consciousness, or focal neurologic deficits. Her past medical history is significant for myocardial infarction (MI) 1 year ago, status post percutaneous transluminal coronary angioplasty complicated by residual angina, and severe asthma, managed medically. The patient is afebrile, and the vital signs are within normal limits. A physical examination is unremarkable. A noncontrast computed tomography (CT) scan of the head appears normal. Which of the following is the best prophylactic treatment for this patient’s most likely diagnosis?", "answer": "Valproic acid", "options": {"A": "Sumatriptan", "B": "Amitriptyline", "C": "Valproic acid", "D": "Propranolol", "E": "Ibuprofen"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 37-year-old 11-week primigravida will soon undergo a prenatal evaluation. The doctor wants to exclude chromosomal abnormalities with a test. He tells her that the test includes extracting a blood sample to determine the chances of having certain genetic conditions. This process involves analyzing fetal DNA in the mother’s blood. What conditions can the given test predict?", "answer": "Trisomy 21, trisomy 13, trisomy 18, fetal sex", "options": {"A": "Trisomy 21, Ebstein anomaly", "B": "Trisomy 21, trisomy 13, trisomy 18, fetal sex", "C": "Trisomy 21, trisomy 13, spina bifida", "D": "Trisomy 21, spina bifida", "E": "Trisomy 21, spina bifida, fetal sex"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 41-year-old man presents with progressive fatigue, pain in the front of the chest, and difficulty breathing with minimal exertion while trying to sleep. He reports having a flu-like illness consisting of fatigue, muscle pain, and cough 10 days ago that resolved spontaneously without seeking a medical help. He has no past medical history. He does not smoke cigarettes or drink alcohol. His vital signs include a blood pressure of 100/70 mm Hg, a temperature of 37.5°C (99.5°F), and a regular radial pulse of 105/min. On physical examination, the patient looks tired, the jugular venous pressure is elevated, pulmonary rales are present on both sides, and an S3 gallop is audible. His ECG shows nonspecific ST-segment and T-wave abnormalities. A 2-dimensional echocardiogram shows global left ventricular motion abnormalities and dilatation of the left ventricle. Troponin I  and Creatine Kinase-MB are elevated. Which of the following is the most likely mechanism of the patient illness?", "answer": "Viral-mediated inflammation with local and systemic immunological activation", "options": {"A": "Incomplete filling of the cardiac chambers due to thickening of the pericardium", "B": "Rupture of an atherosclerotic plaque in the coronary artery", "C": "Viral-mediated inflammation with local and systemic immunological activation", "D": "Infection of the endocardial surface of the heart with microembolization and immune complex deposition", "E": "Immune-mediated inflammation of the heart triggered by a preceding streptococcal infection"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A group of epidemiologists is studying the rates of cardiac surgeries performed in several Southeast Asian countries compared to the United States. Results show a significant increase in the number of mitral valve replacements performed in Vietnam in adults aged 30–50 years compared to the same age group in the United States. Which of the following public health interventions is most likely to decrease this number?", "answer": "Prompt antibiotic treatment for bacterial pharyngitis", "options": {"A": "Prompt antibiotic treatment for bacterial pharyngitis", "B": "Improved access to drug rehabilitation centers", "C": "Genetic screening program for FBN1 gene mutation", "D": "Childhood vaccination against Corynebacterium diphtheriae", "E": "Screening echocardiography for prolapsed anterior mitral valve leaflets"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 31-year-old male presents to his primary care physician complaining of low back pain and fevers. He reports a four-day history of intermittent fevers, chills, and low back pain. He denies trauma or recent illness. His past medical history is notable for recurrent renal stones, diabetes mellitus, and alcohol abuse. He takes metformin but admits to missing several doses. He has had multiple sexual partners and uses condoms intermittently. His temperature is 100.6°F (38.1°C), blood pressure is 110/70 mmHg, pulse is 110/min, and respirations are 21/min. On examination, he demonstrates mild tenderness to palpation along his lower back. Sensation to touch is intact in the bilateral lower extremities. Strength in leg and hip flexion and extension is 5/5 bilaterally. The physician is unable to perform a digital rectal examination due to pain. A urinalysis demonstrates leukocytes. Which of the following treatment regimens is most appropriate in this patient?", "answer": "Ceftriaxone and doxycycline", "options": {"A": "Piperacillin and tazobactam", "B": "Ampicillin and gentamicin", "C": "Ciprofloxacin and trimethroprim-sulfamethoxazole", "D": "Terazosin", "E": "Ceftriaxone and doxycycline"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 12-year-old boy is brought to his pediatrician in order to be medically cleared for playing baseball. On presentation, the boy’s only complaint is that he has never been able to completely keep up with his classmates during gym or on the playground because he feels fatigued and short of breath. A review of his prior medical history reveals that he hit all his developmental milestones as expected and has otherwise been healthy. He lives with his parents and eats a diet consisting of mostly fast food and soda. Physical exam reveals a thin, pale boy with decreased color under his eyelids. A panel of hematologic tests are obtained with the following results:\n\nHemoglobin: 11 g/dL\nLeukocyte count: 4,250/mm^3\nPlatelet count: 185,000/mm^3\nMean corpuscular volume: 116 µm^3\nBlood smear: neutrophils with extra lobes\n\nCrystals are also found within this patient's urine. Which of the following treatments would be effective for this patient’s most likely condition?", "answer": "Administration of uridine", "options": {"A": "Administration of uridine", "B": "Administration of purine", "C": "Cobalamin supplementation", "D": "Folate supplementation", "E": "Low protein diet"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 27-year-old woman presents to her primary care physician for a follow-up appointment. At her previous visit she had missed her previous two menses and also had a blood pressure of 147/100 mmHg. The patient has a past medical history of anxiety, depression, bulimia nervosa and irritable bowel syndrome. Her physician prescribed her an exercise program as well as started her on hydrochlorothiazide and ordered lab work. The results of the patient's lab work are below:\n\nSerum:\nNa+: 145 mEq/L\nK+: 2.9 mEq/L\nCl-: 100 mEq/L\nHCO3-: 30 mEq/L\nBUN: 18 mg/dL\nCa2+: 10.9 mg/dL\nMg2+: 2.0 mEq/L\nCreatinine: 1.2 mg/dL\nGlucose: 110 mg/dL\n\nThe patient's blood pressure at this visit is 145/100 mmHg and she has still not experienced her menses. Her cardiac, abdominal, and pulmonary exams are within normal limits. Inspection of the patient's oropharynx is unremarkable as is inspection of her extremities. The patient is started on furosemide and sent home. Which of the following is the most likely cause of this patient's presentation?", "answer": "Increased mineralocorticoid production", "options": {"A": "Increased mineralocorticoid production", "B": "Vomiting", "C": "Obesity", "D": "Increased reabsorption at the collecting duct", "E": "Decreased renal artery blood flow"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 59-year-old man is brought to the emergency room by his wife. Thirty minutes ago, he was carrying heavy moving boxes from his house to a truck when he felt short of breath and suddenly lost consciousness. His wife states that he fell to the ground and was unresponsive for 15 seconds before he regained consciousness. He was not confused after this episode. He does not have chest pain. On questioning, he recalls experiencing episodic shortness of breath and chest tightness while playing tennis over the past year. These symptoms resolved with rest. He has no personal history of serious illness and takes no medication. Vital signs are within normal limits. His temperature is 36.7°C (98°F), heart rate is 95/min and pulse is delayed but regular, respirations are 20/min, and blood pressure is 104/80 mm Hg. Which of the following is most likely to confirm the diagnosis?", "answer": "Echocardiogram", "options": {"A": "CT angiography", "B": "Echocardiogram", "C": "Cardiac enzymes", "D": "Carotid duplex ultrasonography", "E": "Electroencephalogram\n\""}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A previously healthy 2-year-old girl is brought to the physician by her mother because of a dry, harsh cough for 2 days that worsens at night. She has also had mild rhinorrhea and fever. Her older brother has asthma and had a cold last week. Immunizations are up-to-date. She appears to be in mild distress. Her temperature is 38.1°C (100.5°F), pulse is 140/min, respirations are 35/min, and blood pressure is 99/56 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 96%. Examination shows clear rhinorrhea and a dry, hoarse cough. There is mild inspiratory stridor upon agitation that resolves with rest. The remainder of the examination shows no abnormalities. Which of the following is the most appropriate initial step in treatment?", "answer": "Cool mist and dexamethasone", "options": {"A": "Ceftriaxone", "B": "Bronchoscopy", "C": "Chest x-ray", "D": "Cool mist and dexamethasone", "E": "Noninvasive positive pressure ventilation"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 78-year-old man comes to the physician for evaluation of progressive hearing loss in both ears over the past year. He has difficulties understanding conversations in crowded places and when more than one person talks at the same time. He has no dizziness, ear discharge, ringing noise, or ear pain. He has a history of hypertension, hypercholesterolemia, and type 2 diabetes mellitus. Medications include enalapril, metformin, and atorvastatin. Vital signs are within normal limits. Otoscopic examination shows pearly gray, translucent tympanic membranes with a normal light reflex. A vibrating 512 Hz tuning fork is placed on the left mastoid process. Once the patient no longer hears a tone, the fork is held over the ipsilateral ear and the patient reports to hear the tone again. The same test is repeated on the right side with similar results. There is no lateralization when a vibrating 512 Hz tuning fork is placed in the middle of the forehead. Which of the following is the most likely diagnosis?", "answer": "Presbycusis", "options": {"A": "Cerumen impaction", "B": "Ototoxicity", "C": "Cholesteatoma", "D": "Vestibulocochlear nerve damage", "E": "Presbycusis"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 35-year-old woman, gravida 3, para 2, at 37 weeks' gestation comes to the physician for a prenatal visit. She feels well. She states that she did not follow up with her gynecologist on a regular basis due to a busy work schedule. Pregnancy and delivery of her first two children were uncomplicated. Her blood pressure was 127/75 mm Hg at her initial obstetrics appointment. Her temperature is 37.2°C (99°F), pulse is 90/min, and blood pressure is 145/95 mm Hg. Pelvic examination shows a uterus consistent in size with a 37-week gestation. Physical examination shows 2+ edema in the lower extremities. Urinalysis shows:\nBlood negative\nProtein 3+\nRBC 1–2/hpf\nRBC casts negative\nAfter four hours of observation, her vital signs are unchanged. Which of the following is the most appropriate next step in management?\"", "answer": "Induce labor", "options": {"A": "Induce labor", "B": "Administration of methyldopa", "C": "Reassurance", "D": "Fetal monitoring with continuous cardiotocography", "E": "Perform C-section\n\""}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 31-year-old presents with self-described complaints of being \"fidgety and irritable\" that is unlike his \"calm personality a few years ago\". What is concerning to him is that his father was diagnosed with a similar condition at the age of 38. His father began a progressive decline - losing interest in his life and family, becoming messy, experiencing involuntary movements, and worsening dementia as he grew older. Genetic tests were performed on the patient which confirmed that he has a larger number of repeats than his father. He is concerned that the disease may begin earlier for him or may have already started. Which of the following trinucleotide repeats is found in this disease?", "answer": "CAG", "options": {"A": "CAG", "B": "CGG", "C": "CTG", "D": "GAA", "E": "UGA"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 48-year-old woman comes to the physician because of a 3-month history of low-grade fever, unintentional weight loss, night sweats, and a right-sided neck mass. Examination shows pallor. There is a non-tender and immobile right-sided cervical mass and enlarged axillary and inguinal lymph nodes. The liver is palpated 4 cm below the right costal margin, and the spleen is palpated 3 cm below the left costal margin. Histopathologic examination of a cervical lymph node biopsy specimen shows a nodular proliferation of centrocytes and centroblasts that stain positive for CD20. Genetic analysis shows a reciprocal translocation of chromosomes 14 and 18. This patient's condition is most likely caused by mutation of an oncogene that encodes for a protein involved in which of the following cellular processes?", "answer": "Inhibition of programmed cell death", "options": {"A": "Hydrolysis of guanosine triphosphate", "B": "Upregulation of cytokine receptor binding", "C": "Transfer of phosphate from ATP to cellular protein", "D": "Inhibition of DNA break repair", "E": "Inhibition of programmed cell death"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 59-year-old man is brought to the emergency department for changes in mental status. His wife noticed that since lunch time today, he has been “zoning out” and forgetting simple things such as where the bathroom is. She decided to call the ambulance as he got uncharacteristically violent during dinner when he threw his plate to the floor. The patient denies fevers, weight loss, chills, chest pain, or shortness of breath, but reports mild abdominal discomfort and some dark stools that he attributes to iron supplements. A physical examination demonstrates a moderate fluid wave of the abdomen and shaking of the hands while the wrists are extended. What is the mechanism of action of the medication that can treat this patient’s condition?", "answer": "Trapping of ammonia in the colon", "options": {"A": "Antagonist against 5-HT3", "B": "Inhibition of the Na+/K+/2Cl- cotransporter at the loop of Henle", "C": "Long-acting somatostatin analog", "D": "Mu-opioid receptor agonist", "E": "Trapping of ammonia in the colon"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "An otherwise healthy 49-year-old man presents to his primary care doctor for routine screening. He does not have any symptoms and take no medications. He has smoked 15–20 cigarettes daily for the past 9 years. His father died of diabetes complications and his mother has been recently diagnosed with proliferative diabetic retinopathy. His blood pressure is 160/95 mm Hg, temperature is 36.9°C (98.4°F), pulse is 90/min, body mass index is 36 kg/m², fasting blood sugar 170 mg/dL, and A1c is 9%. Which of the following manifestations is more specific for this patient’s condition?", "answer": "Acanthosis nigricans", "options": {"A": "Kussmaul respiration", "B": "Unintentional weight loss", "C": "Acanthosis nigricans", "D": "Polydipsia", "E": "Polyurea"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 30-year-old woman is brought to the emergency department because of severe headache and vomiting that started after she was hiking in the mountains at high altitude. She normally lives in a city that is close to sea level. Therapy is initiated with a drug that alkalinizes the urine. Which of the following is the most likely site of action of this drug in the kidney?", "answer": "Proximal convoluted tubule", "options": {"A": "Proximal convoluted tubule", "B": "Ascending loop of Henle", "C": "Glomerulus", "D": "Collecting ducts", "E": "Early distal convoluted tubule"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 35-year-old woman comes to employee health services 30 minutes after a work-related incident. She works as a phlebotomist and reports that blood splashed into her right eye when she was drawing blood from a 30-year-old male patient. Immediately following the incident, she flushed her eye with water for several minutes. The patient from whom she drew blood was admitted for hemoptysis, weight loss, and night sweats. He is an intravenous drug user and is sexually active with several male and female partners. The phlebotomist has no history of serious illness and takes no medications. Her immunizations are up-to-date. Physical examination shows no abnormalities. In addition to drawing her blood for viral serologies, which of the following is the most appropriate next step?", "answer": "Start raltegravir, tenofovir, and emtricitabine", "options": {"A": "Start raltegravir, tenofovir, and emtricitabine", "B": "Start zidovudine", "C": "Start tenofovir and emtricitabine", "D": "Start sofosbuvir and velpatasvir", "E": "Administer hepatitis B immune globulin and vaccine"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 65-year-old Asian woman comes to the physician for a routine health maintenance examination. On questioning, she has had occasional night sweats during the past 2 months. She has not had fevers or weight loss. Seven months ago, she had an acute myocardial infarction and was treated with percutaneous coronary intervention. She has hypertension, hyperlipidemia, and gastroesophageal reflux disease. She has smoked one pack of cigarettes daily for 37 years. Current medications include aspirin, atorvastatin, ramipril, metoprolol, and esomeprazole. She is 178 cm (5 ft 10 in) tall and weighs 89 kg (207 lbs); BMI is 29.7 kg/m2. Her temperature is 37.4°C (99.3°F), pulse is 84/min, respirations are 18/min, and blood pressure is 145/80 mm Hg. The lungs are clear to auscultation. Cardiac examination shows an S4. There is a nontender skin lesion near the right large toenail. A photograph of the lesion is shown. The remainder of the examination shows no abnormalities. Which of the following is the most likely diagnosis?", "answer": "Malignant melanoma", "options": {"A": "Cholesterol embolism", "B": "Traumatic subungual hemorrhage", "C": "Malignant melanoma", "D": "Onychomycosis", "E": "Squamous cell carcinoma"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 12-year-old girl brought to the clinic by her mother has a 3-day history of fever and sore throat and hematuria since this morning. The patient’s mother says she had a fever up to 39.5℃ (103.1℉) for the last 3 days and a severe sore throat, which has improved slightly. The mother states that she noticed her daughter had red urine today. The patient’s temperature is 39.3℃ (102.8℉), pulse is 89/min, respiratory rate is 25/min, and blood pressure is 109/69 mm Hg. On physical examination, her pharynx is erythematous. There is significant swelling of the tonsils bilaterally, and there is a white exudate covering them. Ophthalmologic examination reveals evidence of conjunctivitis bilaterally. Otoscopic examination is significant for gray-white tympanic membranes bilaterally. The remainder of the exam is unremarkable. A urine dipstick is performed and shows the following results:\nUrine Dipstick\nSpecific Gravity 1.019\nGlucose None\nKetones None\nNitrites Negative\nLeukocyte Esterase Negative\nProtein None\nBlood 3+\n Which of the following microorganisms is the most likely cause of this patient’s symptoms?", "answer": "Adenovirus", "options": {"A": "Streptococcus pyogenes", "B": "Adenovirus", "C": "Epstein-Barr virus", "D": "Escherichia coli O157:H7", "E": "Proteus mirabilis"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 73-year-old woman with a past medical history of diabetes, hypertension, and hyperlipidemia presents to the emergency department with swelling in her left neck. The onset was a few months ago. She has lost 6.8 kg (15.0 lb) over the same duration. She denies any fever, night sweats or itching. Physical examination reveals a painless swelling in front of her left ear. There is painless lymphadenopathy below the ear. Biopsy of the lymph nodes reveals mucoepidermoid carcinoma of the parotid gland. Surgery is planned and the tumor is removed while trying to preserve a nerve that could be involved. What physical finding would suggest involvement of the nerve in its course through the parotid gland?", "answer": "Inability to smile on the left side", "options": {"A": "Loss of taste on the left anterior 2/3 of the tongue", "B": "Hypersensitivity to sound in the left ear", "C": "Inability to smile on the left side", "D": "Numbness of the left cheek", "E": "Reduced production of tears in the left eye"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 43-year-old man is brought to the emergency department by his wife after a near-syncopal episode. He was doing yard work when he began feeling dizzy and had to lie down. Earlier in the day, he was started on lisinopril. On arrival, he is fully oriented. His pulse is 100/min and blood pressure is 92/60 mm Hg. Serum electrolytes are within normal limits. An ECG shows no evidence of ischemia. Concurrent treatment with which of the following agents most likely predisposed the patient to this episode?", "answer": "Hydrochlorothiazide", "options": {"A": "Atorvastatin", "B": "Ibuprofen", "C": "Hydrochlorothiazide", "D": "Lithium", "E": "Trimethoprim/sulfamethoxazole"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 4-year-old Caucasian girl previously diagnosed with asthma presents with recurrent sinusitis, otitis media, and clubbing of the nail bed. Family history is significant for a distant cousin with cystic fibrosis. A \"sweat test\" is performed and comes back normal. What additional diagnostic test would be helpful in establishing a diagnosis?", "answer": "Nasal transepithelial potential difference", "options": {"A": "Nasal transepithelial potential difference", "B": "Chest radiograph", "C": "Skeletal survey", "D": "Complete blood cell count", "E": "Urinalysis"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 35-year-old woman presents with a complaint of oral ulcers. It is the third recurrence of ulcers in the last 8 months. She is sexually active and complains of dyspareunia. Examination shows the presence of a uveitis. Which of the following would most likely be positive in this patient?", "answer": "HLA-B51", "options": {"A": "Anti-double stranded (Ds) DNA", "B": "HLA-B51", "C": "ANCA", "D": "HLA-B27", "E": "ANA"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 22-year-old female software analyst presents to a medical clinic for evaluation of tingling and numbness in both hands for the past 2 months. Her symptoms are usually aggravated by the end of the work day and absent on most off days. She has been a type I diabetic for 2 years and is currently on insulin. She admits to being sexually active but has had irregular periods for the past 3 months. A urine pregnancy test is negative. What is the most likely cause of this patient’s symptoms?", "answer": "Hypothyroidism", "options": {"A": "Hypothyroidism", "B": "Acute intermittent porphyria", "C": "Amyotrophic lateral sclerosis", "D": "Diabetic neuropathy", "E": "Multiple sclerosis"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 60-year-old male presents to his primary care physician complaining of fatigue. He reports a six-month history of gradually worsening tiredness. More recently, he has experienced intermittent fevers and night sweats. His temperature is 99.5°F (37.5°C), blood pressure is 115/80 mmHg, pulse is 80/min, and respirations are 18/min. On examination, painless cervical lymphadenopathy is noted. A lymph node biopsy is performed and karyotypic analysis of the biopsy reveals an 11;14 translocation. What is the normal function of the protein that is overexpressed due to the translocation seen in this patient?", "answer": "Mediate cell cycle transition to S phase", "options": {"A": "Inhibit apoptosis", "B": "Promote cell growth", "C": "Mediate cell cycle transition to mitosis", "D": "Mediate cell cycle transition to G2 phase", "E": "Mediate cell cycle transition to S phase"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "An 8-year-old boy presents with abdominal pain and constipation. The patient’s mother says that the symptoms gradually onset 2 months ago. The patient describes the pain as moderate to severe, gnawing and diffusely localized. No significant past medical history and no current medications. The patient lives in a house built in the 1990s with his parents and has a sister who goes to daycare. His mother mentioned that he is a good student but has been irritable lately, and his homework has been full of careless mistakes. The vital signs include: temperature 37.0°C (98.6°F), blood pressure 100/65 mm Hg, pulse 82/min, respiratory rate 19/min, and oxygen saturation 99% on room air. On physical examination, the patient is alert and cooperative. The abdomen is diffusely tender to palpation with no rebound or guarding. There is a left wrist drop. A nontender, flat bluish line above the gums is noted. Laboratory results are significant for the following:\nSodium 141 mEq/L\nPotassium 4.1 mEq/L\nChloride 101 mEq/L\nBicarbonate 25 mEq/L\nBlood urea nitrogen (BUN) 27 mg/dL\nCreatinine 1.7 mg/dL\nGlucose (fasting) 80 mg/dL\n    White blood cell (WBC) count 8,700/mm3\nRed blood cell (RBC) count 4.20 x 106/mm3\nHematocrit 41.5%\nHemoglobin 10.3 g/dL\nPlatelet count 190,000/mm3\nMean corpuscular volume (MCV) 65 mm3\nLead 72 mcg/dL\nWhich of the following is the most appropriate next step in the management of this patient?", "answer": "Chelation therapy with dimercaprol and calcium disodium edetate (EDTA)", "options": {"A": "Measure hair lead level", "B": "Chelation therapy with dimercaptosuccinic acid (succimer)", "C": "Chelation therapy with dimercaprol", "D": "Chelation therapy with dimercaprol and calcium disodium edetate (EDTA)", "E": "Plain abdominal radiographs"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "Two days after undergoing a left total hip replacement, a 68-year-old man has increasing shortness of breath and chest pain for 30 minutes. He has type 2 diabetes mellitus and bilateral osteoarthritis of the hips. Prior to admission to the hospital, his medications were metformin and naproxen. His temperature is 37.8°C (100°F), pulse is 110/min, respirations are 30/min, and blood pressure is 106/70 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 89%. The lungs are clear to auscultation. Cardiac examination shows no abnormalities. The right lower extremity is swollen. Right foot flexion in an upward direction causes pain in the right calf. Pedal pulses are palpable. Supplemental oxygen and intravenous fluid resuscitation are begun. His hematocrit is 30%. Arterial blood gas analysis on room air shows:\npH 7.48\npCO2 27 mm Hg\npO2 68 mm Hg\nHCO3- 23 mEq/L\nAn electrocardiogram shows sinus tachycardia and right axis deviation. Which of the following is the most appropriate next step in management?\"", "answer": "Obtain a spiral CT angiogram", "options": {"A": "Perform compression ultrasonography", "B": "Administer alteplase", "C": "Obtain a spiral CT angiogram", "D": "Obtain an x-ray of the chest", "E": "Perfom an echocardiography"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "An 11-month-old male presents to the emergency department with his father after “passing out” at home. His father reports that the patient started crying after his older brother took a toy away from him. The patient was difficult to soothe and then suddenly stopped breathing. His father reports that his lips turned slightly blue, and the patient’s entire body became limp. The episode lasted a few seconds, and the patient seemed to act normally afterwards. The patient’s father notes that the patient’s older brother had similar episodes as a child. He denies any family history of neurological disease. The patient’s temperature is 98.5°F (36.9°C), blood pressure is 86/64 mmHg, pulse is 98/min, and respirations are 26/min. On physical exam, the patient is in no acute distress playing on his father’s lap. The patient's neurological exam is unremarkable. Which of the following is the best next step in management?", "answer": "Observation and reassurance", "options": {"A": "Arterial blood gas", "B": "Echocardiogram", "C": "Electroencephalogram (EEG)", "D": "Electrocardiogram (ECG)", "E": "Observation and reassurance"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 27-year-old woman presents to the emergency department for pain in multiple joints. She states that she has had symmetric joint pain that started yesterday and has been worsening. It is affecting her wrists, elbows, and shoulders. She also endorses a subjective fever and some fatigue but denies any other symptoms. The patient works as a schoolteacher and is generally healthy. She is currently sexually active with 2 male partners and uses condoms occasionally. Her temperature is 100°F (37.8°C), blood pressure is 122/85 mmHg, pulse is 88/min, respirations are 14/min, and oxygen saturation is 99% on room air. Her laboratory values are within normal limits. Physical exam is notable for joint stiffness and pain in particular of the metacarpophalangeal (MCP), proximal interphalangeal (PIP), and the wrist. The patient is discharged with ibuprofen. Four weeks later, the patient follows up at her primary doctor and notes that her symptoms have improved and she is no longer taking any medications for symptom control. Which of the following is the most likely diagnosis?", "answer": "Parvovirus B19", "options": {"A": "Gonococcal arthritis", "B": "Parvovirus B19", "C": "Rheumatoid arthritis", "D": "Systemic lupus erythematosus", "E": "Transient synovitis"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 57-year-old man with HIV and GERD comes to the emergency department because of productive cough with malodorous phlegm and night sweats for the past week. He has smoked 1 pack of cigarettes daily for 30 years and he drinks 8–10 beers daily. His temperature is 38.9°C (102.0°F). Physical examination shows coarse crackles and dullness to percussion at the right lung base. Scattered expiratory wheezing is heard throughout both lung fields. The CD4+ T-lymphocyte count is 280/mm3 (N ≥ 500). An x-ray of the chest is shown. Which of the following is the most likely cause of this patient's symptoms?", "answer": "Aspiration pneumonia", "options": {"A": "Bronchiectasis", "B": "Pneumocystis pneumonia", "C": "Adenocarcinoma in situ", "D": "Tuberculosis", "E": "Aspiration pneumonia"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 20-year-old woman is brought to the emergency department by her boyfriend for right arm and leg weakness, numbness, and tingling that has been resolving gradually. The symptoms started 4 hours ago after she had an argument with her boyfriend during which she slapped and kicked him. She says she has been limping and cannot use her right arm anymore. She has never had similar symptoms in the past. She has a history of genital herpes and trichotillomania. She is alert and oriented. Physical examination shows upper and lower face symmetry and normal speech. She has 5/5 strength in all extremities and 5/5 right ankle plantar flexion when lying down. She has 4/5 strength in the right arm and leg when ambulating. She cannot stand on her toes when asked. Her deep tendon reflexes are 2+ bilaterally. She has normal proprioception, light touch sensation, and two-point discrimination in all extremities. She has a negative Spurling test. CT of the head without contrast shows no abnormalities. Which of the following is the most appropriate next step in management?", "answer": "Provide patient education", "options": {"A": "Administer alteplase", "B": "Provide patient education", "C": "Start physical therapy", "D": "Prescribe aspirin", "E": "Start biofeedback therapy\n\""}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 14-year-old female presents to her psychiatrist in hopes that she can find help in dealing with the sexual abuse that occurred in her childhood. While retelling her story of the numerous encounters the patient had with her abuser, the psychiatrist begins to feel protective and parental towards the client, wishing that he could have somehow helped the young girl. Which of the following best describes the feelings that the psychiatrist has for the patient?", "answer": "Countertransference", "options": {"A": "Transference", "B": "Countertransference", "C": "Identification", "D": "Sublimation", "E": "Projection"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "Which of the following trinucleotide DNA sequences would initiate protein translation when converted to mRNA?\nNote: sequences are written 3'-->5'", "answer": "TAC", "options": {"A": "TAC", "B": "ACT", "C": "ATC", "D": "ATT", "E": "AAA"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 47-year-old woman visits the emergency department due to painful, swollen fingers in both of her hands. She has worked as a bus driver for the county school system for the last 20 years. Her past medical history is significant for a transient ischemic attack 5 years ago. She reports that she has lost weight in the last 2 months although there have been no changes in her diet. She also says that she generally feels fatigued all day. On examination, nodules are seen over her Achilles tendon and both wrists are erythematous, swollen, and tender to touch. Laboratory tests are presented below:\nHemoglobin: 11.0 g/dL\nHematocrit: 40.5%\nLeukocyte count: 7400/mm3\nMean corpuscular volume: 80.1 μm3\nPlatelet count: 210,000/mm3\nErythrocyte sedimentation rate: 55 mm/h\nAnti-cyclic citrullinated peptide antibody: 45 (Normal reference values: < 20)\nWhich side-effect is associated with the drug of choice for the treatment of this patient’s condition?", "answer": "Pneumonitis", "options": {"A": "Retinopathy", "B": "Osteoporosis", "C": "Arterial hypertension", "D": "Pneumonitis", "E": "Reactivation of latent tuberculosis"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 37-year-old man comes to the emergency room with fever, chills, and left lower leg pain for 2 days. He was recently discharged from the hospital after arthroscopic knee surgery. Physical examination shows an erythematous lesion with poorly defined margins over the left shin but no fluctuance. Treatment with an intravenous antibiotic is begun. Shortly after starting the infusion, the patient develops flushing, erythema, and pruritus of the upper body. The symptoms resolve after discontinuation of the infusion. Before the next dose with the same agent, the patient is given diphenhydramine and ranitidine and the antibiotic is subsequently given at a slower infusion rate without complications. The patient was most likely treated with an antibiotic that binds to which of the following?", "answer": "D-alanyl-D-alanine", "options": {"A": "Transpeptidase", "B": "Topoisomerase II", "C": "30S subunit", "D": "Dihydrofolate reductase", "E": "D-alanyl-D-alanine"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 55-year-old man presents with worsening weakness of the left hand and progressive difficulty in walking for the last 2 months. He says he was previously healthy and active, hiking every weekend, but because of his increasing weakness and incoordination while walking, he stopped his weekly hiking excursion. His past medical history is unremarkable. Current medications are a daily multivitamin and occasional acetaminophen for headaches. He has no significant family history. The patient denies smoking, recreational drug use, or drinking. His vitals include: pulse 70/min, respirations 14/min, temperature 37.0°C (98.6°F), and blood pressure 130/80 mm Hg. Physical examination reveals fasciculations in the tongue and distal extremities. The left forearm shows significant atrophy, and mild lower limb muscle atrophy is also seen bilaterally. Hyporeflexia (1+) is present in the left arm, while hyperreflexia (3+) is seen in the legs bilaterally. Babinski’s sign is positive bilaterally. The patient's speech is notably slow but no evidence of productive or expressive aphasia is present. The cranial nerves are intact. Which of the following pathologies most likely underlies this patient’s condition?", "answer": "Loss of the pyramidal tract neurons and anterior horn cells of the spinal cord", "options": {"A": "Demyelination of neurons in various parts of the brain", "B": "Degeneration of the dorsal columns of the spinal cord", "C": "Infarction of the posterior limb of the internal capsule", "D": "Loss of the anterior horn cells of the spinal cord", "E": "Loss of the pyramidal tract neurons and anterior horn cells of the spinal cord"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 14-year-old male who is a recent immigrant from India visits your office complaining of difficulty walking. Physical examination reveals weakness upon right leg extension and absent right patellar tendon reflex. PCR of a stool sample and a swab of the pharynx both yield viral RNA. Which of the following best describes the likely causal virus of this patient’s symptoms?", "answer": "Non-enveloped, positive stranded, icosahedral virus", "options": {"A": "Enveloped, positive stranded, helical virus", "B": "Non-enveloped, positive stranded, icosahedral virus", "C": "Enveloped, positive stranded, icosahedral virus", "D": "Enveloped, negative stranded, helical virus", "E": "Non-enveloped, negative stranded, helical virus"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 21-year-old woman is brought to the emergency department because of the sudden onset of left-sided back pain with radiation to the groin that began 2 hours ago. She has had similar episodes in the past. Her pulse is 103/min. Examination shows a soft and non-tender abdomen. Left costovertebral angle tenderness is present. Leukocyte count is 11,000/mm3. Urine dipstick is positive for blood and a urinary cyanide nitroprusside test is positive. An x-ray of the abdomen shows no abnormalities. Further evaluation of this patient's urine is most likely to show which of the following?", "answer": "Hexagon-shaped crystals", "options": {"A": "pH of 7.8", "B": "Urease-producing bacteria", "C": "Low citrate concentration", "D": "High uric acid concentration", "E": "Hexagon-shaped crystals"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 45-year-old man presents to the emergency department with sudden left lower back pain and bloody urine. The pain is dull and constant. He can not localize exactly where it is. Over the past 2 weeks, he has also gained 3 kg (7 lb) and his shoes feel tight. He denies a history of any chronic medical conditions, recent abdominal trauma or illness, and has never noticed blood in his urine before. In the hospital, his temperature is 36.8°C (98.2°F), the heart rate is 98/min, the respiratory rate is 15/min, and the blood pressure is 135/85 mm Hg. A review of medical records shows that his blood pressure was 115/75 mm Hg 6 months ago. On physical exam, he appears distressed. There are bruises on his left upper arm, chest, and right thigh. The patient does not remember when he got them. His heart has a regular rate and rhythm and his lungs are clear to auscultation bilaterally. He has 2+ pitting edema in both legs up to the knee and his hands appear edematous. A urine dipstick shows 3+ blood and 4+ protein. Additional specimens are sent to chemistry for analysis. What will be most helpful in diagnosing sequelae resulting from the patient’s underlying condition?", "answer": "CT angiogram with contrast", "options": {"A": "CT angiogram with contrast", "B": "Non-contrast CT", "C": "Retrograde urethrogram", "D": "Cystoscopy", "E": "Renal biopsy"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 21-year-old man visits his primary care provider complaining of visual disturbance in both eyes for a month and an episode of abnormal uncontrollable shaking that occurred twice last week. He was previously healthy and did not take any medication. His mother has intermittent muscle weakness and his maternal uncle developed hemiplegia at the age of 35. Neuroimaging shows bilateral occipital lobe infarcts and a skeletal muscle biopsy reveals atypical muscle fibers that stain positive for subsarcomelar structures. The physician suspects a maternally inherited genetic disorder. The difference in the level of severity of this disorder among family members in best explained by which of the following?", "answer": "Heteroplasmy", "options": {"A": "Heteroplasmy", "B": "Mosaicism", "C": "Variable penetrance", "D": "Anticipation", "E": "Uniparental disomy"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "Your hospital administrators want to provide you with a tool to analyze the usage of emergency department visits by patients in your high-risk practice. The following graph is displayed on the dashboard of your electronic medical record to show you how often your patients utilize the ED so that you can provide higher quality and more cost-effective care. The X-axis indicates the number of times a patient has been to the ED in the last year. The Y-axis indicates the number of patients who fit into that category. How would you describe the data shown below?", "answer": "It is positively-skewed, with mean > median > mode.", "options": {"A": "It is positively-skewed, with mean > median > mode.", "B": "It is positively-skewed, with mode > median > mean.", "C": "It is positively-skewed, with median > mode > mean.", "D": "It is negatively-skewed, with mode > median > mean.", "E": "It is negatively-skewed, with mean > median > mode."}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 27-year-old G1P0000 at 17 weeks of gestation is interested in participating in a clinical trial for nausea management during pregnancy. The trial will be evaluating the effects of moderate ginger consumption on nausea symptoms. Prior to enrolling in the trial, the investigators explain to the patient that they will be doing a full exam and some special testing to make sure she is experiencing a healthy pregnancy. Which of the following findings would most likely be abnormal during pregnancy?", "answer": "Hypertension", "options": {"A": "Hypertension", "B": "Increased cardiac output", "C": "Increase in factor VII", "D": "Anemia", "E": "Respiratory alkalosis"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 14-year-old Caucasian male of normal weight presents for a well-child checkup. During physical examination, his parents state that their son has been frequenting the bathroom more often than usual and his weight has decreased despite an increase in his caloric intake. Which of the following is most consistent with their son's symptoms?", "answer": "Self-reactive T-cells", "options": {"A": "Increased insulin production by beta-cells", "B": "Self-reactive T-cells", "C": "Amyloid deposits in pancreatic islet cells", "D": "Absence of leukocytic infiltrates in the pancreas", "E": "Hypoglycemia"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 56-year-old woman with a history of stage IIA cervical cancer presents to your office after her 5th episode of a complicated urinary tract infection. She complains of easy fatigability, weakness, and has noted that her shoes no longer fit. The physical examination is unremarkable, except for a blood pressure of 165/90 mm Hg and mild pitting lower extremity edema. The rectovaginal exam revealed no masses. Given the patient’s medical history, the specialist makes a stage IIIB diagnosis; however, to confirm this, he orders abdominal and transvaginal ultrasounds and renal function tests. Which of the following findings would you most likely expect to be reported in the ultrasound?", "answer": "Hydronephrosis", "options": {"A": "Bladder or rectum mucosa invasion", "B": "Distant metastasis", "C": "Involvement of lower third of vagina", "D": "Parametrial invasion by cancer", "E": "Hydronephrosis"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 77-year-old man is brought to the physician because of a 2-day history of increasing shortness of breath and ankle swelling. He has type 2 diabetes mellitus, hypertension, coronary artery disease, and congestive heart failure. Current medications include lisinopril, metformin, and aspirin. He has smoked half a pack of cigarettes daily for 50 years. His temperature is 37.2°C (98.9°F), pulse is 100/min and regular, respirations are 20/min, and blood pressure is 100/65 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 91%. There are jugular venous pulsations 5 cm above the sternal angle. Crackles are heard at both lung bases. Cardiac examination shows an S3 gallop. There is edema from the mid-tibia to the ankle bilaterally. Laboratory studies show:\nHemoglobin 14.1 g/dL\nLeukocyte count 7100/mm3\nSerum\nNa+ 129 mEq/L\nCl- 99 mEq/L\nK+ 4.8 mEq/L\nUrea nitrogen 48 mg/dL\nGlucose 196 mg/dL\nCreatinine 2.1 mg/dL\nWhich of the following is the most appropriate next step in management?\"", "answer": "Discontinue metformin therapy", "options": {"A": "Discontinue metformin therapy", "B": "Begin vancomycin therapy", "C": "Discontinue aspirin therapy", "D": "Begin nitroprusside therapy", "E": "Begin hydrochlorothiazide therapy"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 32-year-old woman, gravida 2, para 1, at 40 weeks' gestation is admitted to the hospital 30 minutes after spontaneous rupture of membranes without labor pains. She delivered her first child vaginally at 38 weeks' gestation. Pregnancy was complicated by hypothyroidism. She has no other history of serious illness. Medications include levothyroxine and a multivitamin. Her pulse is 90/min, respirations are 16/min, and blood pressure is 134/76 mm Hg. Pelvic examination shows a uterus consistent in size with a 40 week gestation. A cardiotocography reading is shown. Which of the following is the most likely cause of the cardiotocography findings?", "answer": "Umbilical cord compression", "options": {"A": "Umbilical cord compression", "B": "Fetal hypothyroidism", "C": "Fetal head compression", "D": "Uteroplacental insufficiency", "E": "Fetal CNS depression"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 55-year-old man presents for a routine check-up. He currently has no complaints, and his last physical and laboratory studies were unremarkable. His past medical history is significant for hypercholesterolemia, well managed with rosuvastatin, and hypertension, well managed with hydrochlorothiazide. His current medications also include aspirin. The patient is afebrile and his vital signs are within normal limits. Physical examination reveals some generalized lymphadenopathy. Laboratory findings are significant for the following:\nWBC 38,000/mm3\nRBC 4.20 x 106/mm3\nHematocrit 27.3%\nHemoglobin 8.3 g/dL\nPlatelet count 355,000/mm3\nA peripheral blood smear and differential shows 92% small normocytic lymphocytes.\nWhich of the following is the most likely diagnosis in this patient?", "answer": "Chronic lymphocytic leukemia", "options": {"A": "Acute myelogenous leukemia", "B": "Acute lymphocytic leukemia", "C": "Chronic myelogenous leukemia", "D": "Chronic lymphocytic leukemia", "E": "Asymptomatic multiple myeloma"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 72-year-old man with a history of diabetes, dyslipidemia, and hypertension presents to the emergency department with sudden-onset right-sided facial paresthesia, word-finding difficulty, and lightheadedness. He was at a restaurant, in general good health, enjoying a dinner with friends when the 1st symptoms started. He takes atorvastatin, lisinopril, hydrochlorothiazide, and a multivitamin every day. A review of symptoms was negative. His symptoms spontaneously resolved after 5 minutes. In the emergency department, the vital signs included: blood pressure of 132/80 mm Hg, heart rate of 86/min, respiratory rate of 20/min, and oxygen saturation of 99% on room air. The laboratory results included:\nHemoglobin 11.3 g/dL\nHematocrit 33%\nWBC count 9,800/mm3\nPlatelet count 247,000/mm3\nInternational normalized ratio (INR) 1.1\nProthrombin time (PT) 11.5 seconds\nPartial thromboplastin time (PTT) 32 seconds\nHis electrocardiogram (ECG) and his head computed tomography (CT) scan were normal. A duplex ultrasound scan shows 70–89% stenosis in the left carotid artery and 50% in the right. In the course of evaluation, his aphasia recurred for 3 minutes. A brain magnetic resonance imaging (MRI) scan was negative for areas of ischemia or intracranial hemorrhage. His symptom recurrence prompted his hospital admission for inpatient care. What is the next step in management?", "answer": "Carotid endarterectomy", "options": {"A": "IV unfractionated heparin", "B": "Enoxaparin", "C": "Thrombolysis", "D": "Carotid endarterectomy", "E": "Carotid artery stenting"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 70-year-old woman visits her physician complaining of dry mouth and dry eyes. She states that she has recently been having difficulty wearing her dentures on account of her dry mouth. She also says that her tongue sticks to the roof of her mouth, making it difficult to speak and swallow food. Her eyes have also been burning, and she has had to use over the counter eye drops much more often. These symptoms have persisted for several months. On physical exam, mild bilateral enlargement of the parotid glands was noted, and an intraoral examination revealed a red, dry, and smooth mucosal surface on the dorsum of the tongue and buccal mucosa. The patient has a history of hypertension, for which she takes lisinopril. Which of the following is the best 1st step in this patient’s management?", "answer": "Perform a Schirmer test and obtain anti-Ro/anti-La titers", "options": {"A": "Administer prednisone", "B": "Obtain an electrocardiogram (ECG)", "C": "Perform a Schirmer test and obtain anti-Ro/anti-La titers", "D": "Perform a parotid gland biopsy", "E": "Refer the patient to an ophthalmologist"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 61-year old obese nulliparous female presents to your office with right lower quadrant abdominal pain. Her medical history is significant for breast cancer and past use of postmenopausal estrogen replacement therapy. This patient most likely has elevated levels of which of the following?", "answer": "CA 125", "options": {"A": "hCG", "B": "AFP", "C": "CA 19-9", "D": "CA 15-3", "E": "CA 125"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 28-year-old man comes to the physician because of a swollen, tender left knee for the past 4 days. During this period, the patient has had pain with urination. The patient has no history of serious illness and takes no medications. He is sexually active with two male partners and they use condoms inconsistently. His older sister has systemic lupus erythematosus. He is 180 cm (5 ft 11 in) tall and weighs 98 kg (216 lb); BMI is 30.1 kg/m2. His temperature is 37°C (98.6°F), pulse is 83/min, and blood pressure is 140/75 mm Hg. Examination shows conjunctivitis bilaterally. The left knee is warm, erythematous, and tender to touch; range of motion is limited. Laboratory studies show an erythrocyte sedimentation rate of 62 mm/h. Urinanalysis shows WBCs. Further evaluation of this patient is most likely to reveal which of the following?", "answer": "HLA-B27 positive genotype", "options": {"A": "HLA-B27 positive genotype", "B": "Hiking trip two months ago", "C": "Positive anti-dsDNA antibodies", "D": "Intravenous drug use", "E": "Chondrocalcinosis of the left knee"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 21-year-old man comes to the physician because of nervousness and difficulty sleeping over the past 2 weeks. Three months ago, he started a new team project at his job. He says that he has trouble falling asleep at night because he thinks about the project. He insists on checking the work of his teammates and spends several hours each week making elaborate lists and schedules. He refuses to let others take on more tasks because he thinks that only he can complete them satisfactorily. The project deadline has already been postponed once. He says, “My teammates never understand how important it is to do things the right way.” Ever since high school, he has used the majority of his time to plan out assignments and does not have time to regularly participate in social activities. Which of the following is the most likely diagnosis?", "answer": "Obsessive-compulsive personality disorder", "options": {"A": "Obsessive-compulsive personality disorder", "B": "Obsessive-compulsive disorder", "C": "Generalized anxiety disorder", "D": "Schizoid personality disorder", "E": "Adjustment disorder with mixed anxiety and depressed mood\n\""}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 52-years-old man presents with a history of recurrent episodes of unilateral headaches. He says the episodes are short-lived (usually lasting for a few seconds to 3-4 minutes), and he describes them as a severe throbbing orbital headache, accompanied by ipsilateral conjunctival injection and lacrimation. He says that often the episodes seem to be triggered by a cutaneous stimulus touching the face or while chewing food. Sometimes, he says he experiences countless attacks during a single day. The headaches do not respond to indomethacin and any other non-steroidal anti-inflammatory drug (NSAID). Which of the following drugs is most likely to be effective as a preventive therapy in this patient?", "answer": "Lamotrigine", "options": {"A": "Ibuprofen", "B": "Acetaminophen", "C": "Lamotrigine", "D": "Nifedipine", "E": "Amitriptyline"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 55-year-old obese man presents to the emergency department with abdominal pain. His pain started 2 days ago and has been worsening steadily. His only current medication is allopurinol. His temperature is 101.0°F (38.3°C), blood pressure is 157/98 mmHg, pulse is 120/min, respirations are 17/min, and oxygen saturation is 98% on room air. Physical exam is notable for left lower quadrant abdominal tenderness and rectal exam is unremarkable. A CT scan is performed demonstrating inflamed outpouchings of the colonic mucosa with a 4-cm abscess. Which of the following is appropriate treatment of this patient?", "answer": "CT-guided percutaneous drainage", "options": {"A": "Ciprofloxacin and gentamicin", "B": "CT-guided percutaneous drainage", "C": "Laparoscopy and drainage", "D": "Piperacillin-tazobactam and vancomycin", "E": "Supportive therapy and observation until symptoms abate"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 32-year-old G2P2 woman gives birth to a boy at 39 weeks gestation. The mother recently immigrated from Somalia and had no prenatal care. She refused all intrapartum medications. The boy’s Apgar scores were 7 and 9 at 1 and 5 minutes, respectively. His height and weight were in the 20th and 15th percentiles, respectively. Mother and child were discharged the day after birth. However, 7 days later, the mother presents to the pediatrician because she noticed redness and discharge in her baby's eyes. His temperature is 98.8°F (37.1°C), blood pressure is 105/65 mmHg, pulse is 120/min, and respirations are 22/min. On exam, the boy has scant non-purulent mucoid bilateral eye discharge and conjunctival hyperemia. Which of the following is the most appropriate treatment for this patient?", "answer": "Oral and topical erythromycin", "options": {"A": "Intramuscular ceftriaxone", "B": "Intravenous acyclovir", "C": "Oral and topical erythromycin", "D": "Sterile lubricant with artificial tear preparation", "E": "Topical bacitracin"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 21-year-old woman presents to her physician for a regular follow-up visit. She was diagnosed with relapsing-remitting multiple sclerosis 2 months ago when she suffered a second episode of optic neuritis. She was successfully treated with methylprednisolone pulse therapy and discharged. Today, she only complains of slight fatigue with upper and lower extremity weakness. Her blood pressure is 120/80 mm Hg, her heart rate is 63/min, her respiratory rate is 14/min, and her temperature is 36.7°C (98.0°F). Neurological examination reveals brisk deep reflexes (3+ equal) and decreased strength (4/4) in the upper limbs. The rest of the examination is unremarkable. The patient is prescribed a drug that is an inhibitor of ɑ4-integrin (CD49d) for the prevention of relapses. She is concerned about the side effects of this drug, among which is increased susceptibility to the upper respiratory tract and urinary tract infections. Inhibition of which of the following processes is the best explanation for such adverse effects?", "answer": "Tight adhesion of leukocytes to the endothelial cells", "options": {"A": "Tight adhesion of leukocytes to the endothelial cells", "B": "Expression of selectins on the surface of endothelial cells", "C": "Formation of tight bounds between leukocytes and endothelial selectins", "D": "Chemotaxis of leukocytes", "E": "Inhibition of interaction between platelet endothelial cell adhesion molecules (PECAMs) on the surfaces of leukocytes and endothelial cells"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 64-year-old man presents to the clinic complaining of low back pain. He was diagnosed with benign prostatic hypertrophy several years ago, which worsened last year. A hard nodule was felt on a digital rectal exam, which led to a prostate biopsy that revealed high-grade adenocarcinoma. A bone scan at that time showed small, focal abnormalities in the lumbar spine. He subsequently underwent radiation therapy to his prostate and pelvic lymph nodes. He was then placed on leuprolide and an anti-androgen. He was doing well until 2 months ago when he developed low back pain, which has worsened since then. He reports that the pain is 8/10 and nearly constant. He states that the pain not only affects his ability to fall asleep but also wakes him up at night. The pain is mildly alleviated by ibuprofen. In addition to prostate cancer, his medical history is significant for hypertension, hyperlipidemia, recurrent nephrolithiasis, and gastroesophageal reflux disease. He takes aspirin, lisinopril, rosuvastatin, and pantoprazole. Upon physical examination, there is midline tenderness within the lumbar region. Magnetic resonance imaging of the spine is obtained, which shows bony metastasis to the L2 and L3 spine without evidence of fracture or spinal cord compression. His prostate-specific antigen is 17.5 ng/mL. Which of the following is the best next step in management?", "answer": "External radiation therapy", "options": {"A": "Calcium and vitamin D supplementation", "B": "External radiation therapy", "C": "Flutamide", "D": "Kyphoplasty", "E": "Zoledronic acid"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "Two days after undergoing internal fixation of a displaced right femoral fracture sustained during a motor vehicle accident, a 34-year-old woman develops sudden shortness of breath. On examination, she is oriented only to person. Her temperature is 38.3°C (100.9°F), pulse is 122/min, respiratory rate is 31/min, and blood pressure is 152/90 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 83%. There are several scattered petechiae on the anterior chest wall. Her hemoglobin concentration is 10.3 g/dL, leukocyte count is 9,500/mm3, and platelet count is 140,000/mm3. Which of the following is the most likely cause of her current condition?", "answer": "Fat globules entering the circulation", "options": {"A": "Platelet thrombus obstructing the pulmonary artery", "B": "Fat globules entering the circulation", "C": "Rupture of a coronary plaque", "D": "Damage to the alveolar capillary endothelium", "E": "Bacterial invasion of the pulmonary parenchyma"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 15-year-old girl comes to the physician for the evaluation of a painless swelling under the left lower jaw for 5 months. Her 18-year-old sister has a history of acute lymphoblastic leukemia that has been in remission for 11 years. The patient's temperature is 37°C (98.6°F) Physical examination shows a 3 × 2 cm swelling on the left side, 4 cm below the base of the mandible and anterior to the sternocleidomastoid muscle. The swelling is soft and fluctuant. It does not move with swallowing, and forced exhalation against a closed glottis does not increase the size of the swelling. Ultrasound shows a round mass with uniform low echogenicity and no internal septations. Which of the following is the most likely diagnosis?", "answer": "Branchial cleft cyst", "options": {"A": "Cystic hygroma", "B": "Lymphadenopathy", "C": "Branchial cleft cyst", "D": "Laryngocele", "E": "Infantile hemangioma"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 70-year-old man is brought to the emergency department by staff of the group home where he resides because of fever, a productive cough, and blood-tinged sputum for 2 days. The staff report that he developed myalgia, headache, and rhinorrhea 7 days ago, which improved initially before worsening again. He has hypertension and Alzheimer disease. Current medications include enalapril and donepezil. On arrival, he is obtunded. His temperature is 39.8°C (103.6°F), pulse is 120/min, respirations are 22/min and shallow, and blood pressure is 100/60 mm Hg. Pulse oximetry on 10 L/min of oxygen via nasal cannula shows an oxygen saturation of 92%. Examination shows scattered crackles and rhonchi throughout both lung fields. An x-ray of the chest shows bilateral lung opacities and multiple small, thin-walled cystic spaces within the basal pulmonary parenchyma. Which of the following is the most likely cause of this patient’s current condition?", "answer": "Infection with Staphylococcus aureus", "options": {"A": "Infection with Staphylococcus aureus", "B": "Pulmonary embolism", "C": "Infection with Aspergillus fumigatus", "D": "Foreign body aspiration", "E": "Granulomatosis with polyangiitis"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 55-year-old man presents to his primary care physician with ear pain. The patient states he has had worsening ear pain for the past 2 days. He describes his pain as 9/10. The patient has a past medical history of diabetes, obesity, and hypertension. His current medications include insulin, metformin, lisinopril, aspirin, and atorvastatin. His temperature is 100.5°F (38.1°C), blood pressure is 177/99 mmHg, pulse is 100/min, respirations are 19/min, and oxygen saturation is 98% on room air. Physical exam reveals a purulent drainage from the ear canal. Manipulation of the ear causes severe pain. Which of the following is the most likely infectious agent?", "answer": "Pseudomonas aeruginosa", "options": {"A": "Haemophilus influenzae", "B": "Moraxella catarrhalis", "C": "Pseudomonas aeruginosa", "D": "Staphylococcus aureus", "E": "Streptococcus pneumoniae"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 19-year-old male college student with no significant medical history presents to the emergency department with altered mental status. His girlfriend said that he drank multiple shots of vodka and gin throughout the weekend and was found slumped on the couch with some vomit on his shirt. He is afebrile, with a blood pressure of 128/60 mmHg, pulse of 100/min, respirations at 25/min, and SpO2 of 95% on room air. His pupils are equal and reactive to light bilaterally. He exhibits no tremors or myoclonus. The remainder of the physical exam is unremarkable. His basic metabolic panel is displayed below:\n\nSerum:\nNa+: 138 mEq/L\nCl-: 90 mEq/L\nK+: 4.0 mEq/L\nHCO3-: 20 mEq/L\nBUN: 30 mg/dL\nGlucose: 100 mg/dL\nCreatinine: 0.8 mg/dL\n\nAn arterial blood gas reveals the following:\n\npH: 7.32\npCO2: 34 mmHg\npO2: 89 mmHg\n\nThe girlfriend is concerned that the patient's breathing appears uncomfortable. How do you respond?", "answer": "His breathing suggests that he needs some fluids", "options": {"A": "His breathing is concerning for hepatic encephalopathy", "B": "His breathing requires evaluation for a pulmonary embolism", "C": "His breathing suggests that he needs some fluids", "D": "His breathing suggests that he has major depression disorder", "E": "You are not his healthcare proxy and I cannot speak to you"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 56-year-old man presents to his primary care provider for a check-up. His past medical history is significant for type 2 diabetes mellitus for 20 years and insomnia.  He takes metformin and insulin NPH. Both of his parents died in a car accident several years ago. He smokes a half of a pack of cigarettes every day and drinks 1-2 beers a day and more on the weekends. Today, his blood pressure is 130/80 mm Hg, pulse is 76/min, respiratory rate is 18/min, and temperature is 36.5°C (97.7°F). On physical exam, he appears obese. His heart has a regular rate and rhythm and his lungs are clear to auscultation bilaterally. A foot exam is performed and is unremarkable. A urinalysis reveals  glucose (++), and protein (+++). Which of the following explains these findings?", "answer": "Glomerular hyperfiltration", "options": {"A": "Glomerular hyperfiltration", "B": "Renal artery stenosis", "C": "Subendothelial immune-complex deposits", "D": "Interstitial atrophy", "E": "Nephrocalcinosis"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 64-year-old man comes to the physician because of a 1-month history of progressively worsening back pain that wakes him up at night. He also reports symptoms of urinary urgency and a weak urine stream. He has no history of serious illness and takes no medications. Rectal examination shows an enlarged and hardened prostate with a nodular surface. After further evaluation and confirmation of the diagnosis, he is started on a new drug. Initially, there is an increase in serum testosterone and dihydrotestosterone levels, followed by a sustained decrease in both serum hormone levels. Treatment with which of the following drugs was most likely initiated in this patient?", "answer": "Leuprolide", "options": {"A": "Leuprolide", "B": "Finasteride", "C": "Ketoconazole", "D": "Cyproterone acetate", "E": "Anastrozole"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 46-year-old man presents to a physician three days after arriving in Morocco. He endorses acute onset of painless, profuse watery diarrhea that appears white and cloudy. The patient denies bloody stool, vomiting, or subjective fevers. Vital signs are T 98.6, HR 120, RR 17, and BP 85/50. On physical exam, the patient has dry mouth, decreased skin turgor, and cold clammy skin. His peripheral pulse is rapid and thready. The toxin responsible for this clinical presentation has a mechanism of action that is most similar to which other toxin?", "answer": "Edema toxin", "options": {"A": "Diphtheria toxin", "B": "Exotoxin A", "C": "Botulinum toxin", "D": "Edema toxin", "E": "Shiga-like toxin"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 25-year-old woman presents to the urgent care center with a one month history of intermittent chest pain that occurs about 2-3 times per week in the early mornings. She does not smoke and has never suffered from chest pain before. She has no family history of early MI. A 12 lead ECG does not show any abnormalities. Creatine kinase and troponin I enzymes are within normal limits. What test will most likely be positive?", "answer": "Ergonovine", "options": {"A": "Ergonovine", "B": "Immediately repeat ECG", "C": "Exercise stress test", "D": "Tilt test", "E": "Kehr's sign"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 28-year-old man is scheduled for skin grafting of the right leg. Four weeks earlier, he underwent open reduction and internal fixation of an open right tibial fracture. The postoperative period at that time was complicated by necrosis of the overlying skin. In the operating room, he is placed on continuous hemodynamic monitoring and anesthetized with intrathecal bupivacaine injected into the L3–L4 spinal interspace. Thirty minutes later, he has severe shortness of breath and lightheadedness and loses consciousness. His temperature is 37.1°C (98.8°F), pulse is 38/min, respirations are 24/min, and palpable systolic blood pressure is 58 mmHg. The skin is diaphoretic and flushed. He withdraws the upper extremities to painful stimuli above the navel. The lungs are clear to auscultation. Heart sounds are not audible. Which of the following is the most likely underlying cause of this patient's symptoms?", "answer": "Loss of sympathetic vascular tone", "options": {"A": "Loss of sympathetic vascular tone", "B": "Obstructive thrombus in the pulmonary artery", "C": "Intravascular volume depletion", "D": "Bone marrow embolism to the lungs", "E": "Type I hypersensitivity reaction"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 42-year-old man with no significant medical history presents to the emergency department with complaints of headache, nausea, and dizziness. He states that he was at home working on his car when he started to feel dizzy and experienced a headache. This progressed to him feeling nauseous. The patient states he went inside and drank some water and felt better; however, when he started working on his car again his symptoms returned. Upon presentation, he states his symptoms have mostly improved except for a persistent headache. His temperature is 98.1°F (36.7°C), blood pressure is 125/84 mmHg, pulse is 87/min, respirations are 18/min, and oxygen saturation is 98% on room air. Neurologic exam is unremarkable. Which of the following is the best next step in management?", "answer": "100% oxygen", "options": {"A": "100% oxygen", "B": "CT", "C": "Hydroxocobalamin", "D": "Ibuprofen and acetaminophen", "E": "MRI"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 19-year-old woman comes to the physician because of severe headaches for the past 3 months. The headaches are pulsating in nature and she describes the pain as 8 out of 10 in intensity. She has visited the emergency department for headaches twice in the past month; during both visits, her blood pressure was elevated. She has polycystic ovarian disease. Her medications include metformin and an oral contraceptive pill. She is 162 cm (5 ft 4 in) tall and weighs 86 kg (190 lb); BMI is 32.8 kg/m2. Her temperature is 37°C (98.6°F), pulse is 99/min, and blood pressure is 168/98 mm Hg. Examination shows hirsutism. Cardiopulmonary examination shows no abnormalities. The abdomen is soft and nontender. An abdominal bruit is heard on the left side. Neurologic examination shows no focal findings. A complete blood count and serum concentrations of electrolytes, urea nitrogen, and creatinine are within the reference range. Plasma free metanephrines are within the reference range. An abdominal ultrasound shows an increased peak systolic velocity in the distal portion of the left renal artery. A contrast-enhanced CT scan of the abdomen shows alternating stenosis and dilation in an 8-mm distal segment of the left renal artery with approximately 75% reduction in the diameter of the vessel. A CT scan of the brain shows no abnormalities. Which of the following is the most appropriate next step in management?", "answer": "Ramipril and percutaneous transluminal angioplasty without stent placement", "options": {"A": "Combination therapy with captopril and valsartan", "B": "Percutaneous transluminal angioplasty without stent placement", "C": "Ramipril and percutaneous transluminal angioplasty without stent placement", "D": "Enalapril and aortorenal bypass with a vein graft", "E": "Aortorenal bypass with a vein graft\n\""}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 28-year-old male is found to have 93% HbA, 2% HbF, and 5% HbA2 on hemoglobin electrophoresis. Which of the following is the most likely diagnosis?", "answer": "Beta-thalassemia minor", "options": {"A": "Sickle cell trait", "B": "Alpha thalassemia major with Hb Bart's", "C": "Beta-thalassemia minor", "D": "Beta-thalassemia major", "E": "Diabetes mellitus"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 76-year-old female is brought to the emergency department for altered mental status. She is accompanied by a nurse from her nursing home. The nurse says that usually the patient is interactive even though she is sometimes forgetful. In the last two days, the patient has been increasingly lethargic and doesn’t respond to the staff’s questions. She also has not been able to get up and use the restroom so the staff has had to change multiple soiled sheets. Her temperature is 102.1°F (38.9°C), blood pressure is 100/74 mmHg, pulse is 120/min, and respirations are 24/min. The patient is combative on arrival but can be subdued with reorientation by the care team. She is not oriented to person, place, or time. Urinalysis shows positive leukocyte esterase and nitrites. Urine culture grows >100,000 CFU of E. coli. The physician team would like to consent this patient for a Foley catheter. Which of the following is the best assessment of the patient’s capacity to make healthcare decisions?", "answer": "Capacity cannot be determined at this time", "options": {"A": "The patient does not have capacity to make decisions", "B": "The patient does have capacity to make decisions", "C": "The patient’s family should be contacted to evaluate her capacity", "D": "The hospital ethics board should be consulted", "E": "Capacity cannot be determined at this time"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 19-year-old woman is brought to the emergency department by ambulance 1 hour after a motor vehicle accident. She has no history of serious illness. She is on mechanical ventilation without any sedation. Her vital signs are within a normal range. Her Glasgow Coma Scale (GCS) is 3. Examination by the attending trauma surgeon and neurologist shows brain death. Laboratory studies show no abnormalities. A search on the state donor registry shows that she has registered as an organ donor. Her father is shocked at the suggestion of organ donation and says that “life is still circulating in her body because it is warm, and she has a normal heartbeat!” While the physician empathizes with the family, which of the following is the most appropriate response?", "answer": "“Brain death is considered legal death just as if her heart was not beating.”", "options": {"A": "“Only after your consent will her organs be removed.”", "B": "“Brain death is considered legal death just as if her heart was not beating.”", "C": "“She is kept alive to preserve her organs.”", "D": "“She is very unlikely to recover.”", "E": "“She will be dead once she is disconnected from advanced life-support.”"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 58-year-old male has had long-term involvement in the world of organized crime. He very recently retired from his post within this organization. This former mafia boss has now suddenly started making large contributions to several local charities. Which of the following ego defenses best characterizes this gentleman's behavior?", "answer": "Altruism", "options": {"A": "Altruism", "B": "Denial", "C": "Displacement", "D": "Sublimation", "E": "Atonement"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 45-year-old man presents with a chronic productive cough that he has had for the past few years. He admits to having smoked 1 pack of cigarettes a day for the past 25 years. A chest radiograph reveals an enlarged heart. The patient's pulmonary function tests would be similar to that seen in a patient with:", "answer": "Emphysema", "options": {"A": "Asymptomatic asthma", "B": "Silicosis", "C": "Emphysema", "D": "Coal worker's pneumonitis", "E": "Prior lung radiation"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 69-year-old gentleman presents to his primary care physician for a general checkup. He states that overall he is doing well. Ever since he retired, he has been working on projects at home, and taking time to exercise every day. He eats a balanced diet, and has been spending time with his wife every evening. Despite this, the patient claims that he feels less well rested when he awakes in the morning. The patient states that he used to sleep nine hours a night in his youth and felt excellent. Now he sleeps seven hours a night and doesn’t feel as well rested as he used to. The patient’s wife states that he seems to sleep peacefully. On physical exam the patient’s neurological exam is within normal limits. The patient is muscular and has a healthy weight and has a pleasant demeanor. He denies feeling fatigued or tired currently. Which of the following physiological changes is most likely in this patient?", "answer": "Decreased melatonin", "options": {"A": "Decreased orexin", "B": "Decreased melatonin", "C": "Increased norepinephrine", "D": "Increased dopamine", "E": "Increased acetylcholine"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 7-year-old boy with sickle cell disease is brought into the clinic by his mother for knee and hip pain. The child has been admitted several times in the past for pain crises managed with fluids and hydromorphone. He started complaining of worsening hip pain over the last several days and now walks with a limp. His temperature is 97.9°F (36.6°C), blood pressure is 84/54 mmHg, pulse is 100/min, respirations are 19/min, and oxygen saturation is 99% on room air. On physical exam, the hip appears normal and is cool to the touch. There is decreased range of motion at the hip and pain with ambulation. Which of the following is the most appropriate next step in management?", "answer": "Radiograph", "options": {"A": "Arthrocentesis", "B": "CT", "C": "Ibuprofen and acetaminophen", "D": "MRI", "E": "Radiograph"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 65-year-old asian man presents to his primary care physician because of abdominal distension, right upper quadrant (RUQ) abdominal pain, decreased appetite, and weight loss for several weeks. He denies smoking or excess alcohol intake. His temperature is 37.1°C (98.7°F), blood pressure is 120/80 mm Hg, and pulse is 85/min. Physical examination reveals a cachectic man with jaundice, palmar erythema, ascites, and a palpable mass in the RUQ. Abdominal ultrasound shows a 3 cm hypoechoic mass in the right lobe of the liver. Alpha fetoprotein (AFP) is 500 μg/L. Which of the following is a risk factor for this patient condition?", "answer": "Chronic hepatitis C infection", "options": {"A": "Exposure to nitrosamines  ", "B": "Cyclophosphamide use", "C": "Exposure to arsenic", "D": "Clonorchis sinensis infection", "E": "Chronic hepatitis C infection"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 71-year-old man from Puerto Rico presents to the emergency department with a 2-week history of abdominal pain. He does not speak much English so his family explains that he has been complaining of intermittent pain that is not associated with any particular actions. Furthermore, his family is concerned because he has been having weight loss and blood in his stool for 3 months. The physician explains that there is a concern for colon cancer and that a colonoscopy is required to evaluate his condition further. The family is afraid that the news will upset the patient so they ask that they be allowed to make healthcare decisions on the patient's behalf. They explain that this is the way that their culture handles medical decisions. What should the physician do in this situation?", "answer": "Call for a Spanish-speaking interpreter to speak with the patient", "options": {"A": "Ask the family to translate the plan for the patient and ask for questions", "B": "Call for a Spanish-speaking interpreter to speak with the patient", "C": "Respect the family's cultural wishes and not discuss the plan with the patient", "D": "Speak directly with the patient in English to ascertain their wishes", "E": "Transfer the care of the patient over to a Spanish-speaking colleague"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 45-year-old man presents to a physician with recurrent episodes of palpitations over the last 3 months. The episodes are self-limiting but cause significant distress and discomfort to the patient. After a detailed electrophysiological workup, the physician concludes that the symptoms occur mainly due to abnormal function of the cardiac ion channels, which primarily produce the plateau phase of the action potential in cardiac myocytes in healthy patients. Which of the following ion channels is dysfunctional in this patient?", "answer": "L-type voltage-gated calcium channels", "options": {"A": "HCN-channels", "B": "Fast sodium channels", "C": "L-type voltage-gated calcium channels", "D": "T-type voltage-gated calcium channels", "E": "Inward rectifier IK1 channels"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 23-year-old man comes to the physician because of severe daytime sleepiness and random episodes of falling asleep during the day for short periods of time. When he wakes up from these episodes, he feels refreshed. He sleeps 6–7 hours at night. He reports that sometimes he is unable to move for a few minutes when he first wakes up in the morning. Last week, he suddenly “lost control” of his legs and neck for about 30 seconds after his classmate had told him a joke. An analysis of this patient's cerebral spinal fluid is most likely to show which of the following findings?", "answer": "Decreased orexin-A", "options": {"A": "Oligoclonal bands", "B": "Decreased orexin-A", "C": "Increased neuron-specific enolase", "D": "Increased 14-3-3 protein", "E": "Anti-ganglioside antibodies"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 73-year-old man is brought to the emergency department 30 minutes after he lost consciousness for 5 minutes while watching a game of summer league football in a seat from the stands in the afternoon. On arrival, he is lethargic and oriented only to person. Three weeks ago, he was treated for hepatitis A. He has type 2 diabetes mellitus and hypothyroidism. Current medications include metformin and levothyroxine. His temperature is 41.5 °C (106.7 °F), pulse is 106/min, respirations are 26/min, and blood pressure is 128/70 mm Hg. Examination shows hot, dry skin. The pupils are equal and reactive to light. Neurologic examination shows no focal findings. Fundoscopy shows proliferative diabetic retinopathy. Cardiopulmonary examination shows no abnormalities. His abdomen is soft and nontender. There is no costovertebral angle tenderness. His serum glucose concentration is 160 mg/dL. An ECG shows a normal sinus rhythm. Which of the following is the most likely underlying cause of this patient's symptoms?", "answer": "Inadequate hypothalamic response", "options": {"A": "Inadequate hypothalamic response", "B": "Accumulation of ammonia due to liver dysfunction", "C": "Metabolic acidosis with ketosis", "D": "Elevation of serum thyroxine levels", "E": "Central dopamine receptor blockade"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 3-year-old boy is brought to the physician for a well-child examination. He feels well. He was born at 38 weeks' gestation and weighed 2766 g (6 lb 2 oz). He now weighs 14 kg (31 lbs). There is no personal or family history of serious illness. His immunizations are up-to-date. He is at 60th percentile for height and 55th percentile for weight. Vital signs are within normal limits. The lungs are clear to auscultation. A grade 3/6 systolic ejection murmur is heard along the upper left sternal border. S2 is widely split and does not vary with respiration. There is a grade 2/6 mid-diastolic murmur along the lower left sternal border. The abdomen is soft and nontender; there is no organomegaly. Which of the following is the most likely diagnosis?", "answer": "Atrial septal defect", "options": {"A": "Patent ductus arteriosus", "B": "Benign heart murmur", "C": "Atrial septal defect", "D": "Pulmonary valve stenosis", "E": "Coarctation of the aorta\n\""}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 30-year-old man presents to the emergency department after being attacked by 2 men a few minutes ago. He was suddenly approached by 2 men holding knives while he was walking on the street nearby. While trying to escape, he was stabbed once in the neck. He is complaining of difficulty breathing and chest pain. He is in apparent distress. His temperature is 36.8°C (98.2°F), the blood pressure is 100/60 mm Hg, the pulse is 110/min, the respirations are 28/min, and the SaO2 is 85% on 4 L oxygen by nasal cannula. Examination of the neck reveals a deep penetrating injury on the right side and distended neck veins. The respiratory exam shows severe tenderness in the right chest, decreased inspiration in the right lung, and tracheal deviation to the left. What is the next best step in the management of this patient?", "answer": "Needle thoracostomy", "options": {"A": "Pericardiocentesis", "B": "Intravenous fluids", "C": "Dobutamine", "D": "Needle thoracostomy", "E": "Pain relief and observation"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "An 8-month-old male presents to your office with a 5-day history of blood in his stool. Abdominal pain is notably absent on history obtained from his parents. Past medical history and physical exam findings are not remarkable. Laboratory findings are significant for mild iron deficiency. Which of the following is characteristic of this patient’s diagnosis?", "answer": "Diagnostic studies localize ectopic gastric tissue.", "options": {"A": "The defect is 4 inches long.", "B": "It may affect neonates but is more common in adolescents.", "C": "It is rare, affecting less than 1% of the population.", "D": "Both males and females are equally affected.", "E": "Diagnostic studies localize ectopic gastric tissue."}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 19-year-old man is brought to a psychiatrist by his mother. The patient’s mother has become increasingly concerned about him since his high school graduation. Although she says that he had been an excellent student in high school, his grades have begun slipping in his second year in college, and he no longer socializes with friends. When she asked him why he no longer talks to his friends, she states that he told her, “They already know where I am. They can see me. They watch me from my bedroom window, so they already know what I’m doing. We don’t need to talk.” She found this to be bizarre, as nearly all of his friends live hours away. The patient states that he feels fine and doesn’t understand why everyone thinks he is crazy. The psychiatrist notices reduced spontaneous movements while the patient is speaking and that he speaks in a monotone with a voice that is soft in volume. He also appears suspicious and defensive, asking the psychiatrist “why are you asking me that?” after each evaluative question. His mood is generally flat with little reactivity or engagement during the course of his interview, but he denies any symptoms of depression or psychosis. No significant past medical history. Family history is not available as he was adopted. Which of the following is the most likely diagnosis in this patient?", "answer": "Schizophrenia", "options": {"A": "Schizoaffective disorder", "B": "Paranoid personality disorder", "C": "Schizophrenia", "D": "Drug abuse", "E": "Brain tumor"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 26-year-old woman comes to the physician because of progressively worsening episodic pelvic pain for 2 years. The pain starts a few days before her menstrual period and lasts about 10 days. She has tried taking ibuprofen, but her symptoms do not improve. Menses have occurred at regular 29-day intervals since menarche at the age of 11 years and last for 5–7 days. The first day of her last menstrual period was 2 weeks ago. She is sexually active with her boyfriend and has noticed that intercourse is often painful; they use condoms inconsistently. Vital signs are within normal limits. Pelvic examination shows a normal vagina and cervix. Bimanual examination shows a normal-sized uterus and no palpable adnexal masses. Urine pregnancy test is negative. Which of the following is the most appropriate next step in management?", "answer": "Prescribe estrogen-progestin contraceptives", "options": {"A": "Perform cervical and urethral swab", "B": "Perform MRI of the pelvis", "C": "Prescribe gonadotropin-releasing hormone agonists", "D": "Prescribe androgenic steroids", "E": "Prescribe estrogen-progestin contraceptives"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A research group has developed a new screening test for HIV that can detect infection 2 weeks earlier than the current gold standard. A rigorous clinical study of this new screening test involving n subjects yields a false-positive probability α, and a false-negative probability, β. Which of the following will most likely reduce the type II error of this screening test?", "answer": "Increasing α", "options": {"A": "Decreasing n", "B": "Increasing α", "C": "Increasing β", "D": "Increasing the specificity of the test", "E": "Decreasing the sensitivity of the test"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 70-year-old female underwent a right total knee arthroplasty without complication. She was discharged to a rehab facility on post-operative day 3. Two days after her discharge from the hospital, she began experiencing pain and swelling of the right leg. Doppler ultrasound imaging at this time revealed a deep venous thrombosis in the right popliteal and tibial veins. The patient was re-admitted and started on an unfractionated heparin infusion. Five days later, doppler ultrasonography of the lower extremities revealed extension of the clot in the right lower extremity to include the common femoral, superficial femoral, popliteal, tibial, and saphenous veins. In addition, a thrombus was noted in the left common femoral vein as well. CBC showed a decrease in platelet count from 195,000/uL on admission to 83,000/uL. Which of the following is the pathophysiology of this patient's presentation?", "answer": "Formation of antibodies to heparin-platelet factor-4 complex", "options": {"A": "Excessive irreversible inactivation of the cyclo-oxygenase enzyme", "B": "Formation of antibodies to heparin-platelet factor-4 complex", "C": "Decreased hepatic synthetic function leading to antithrombin deficiency", "D": "Deposition of immune complex nuclear antigens in kidneys", "E": "Inherited mutation in clotting factor V, which cannot be degraded by activated protein C"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "Three days after surgical repair of a distal right radius fracture, a 62-year-old man develops severe wound pain and fever. His temperature is 39.1°C (102.4°F). Physical examination shows erythema and edema of the right arm that extends up to the elbow. Yellow pus drains from the surgical wound. Cultures from the wound fluid grow gram-positive bacteria in grape-like clusters that are resistant to nafcillin. While treating the patient's condition, the hospital also wants to eradicate the causal pathogen in asymptomatic carriers. Which of the following measures would be most effective?", "answer": "Mupirocin nasal ointment", "options": {"A": "Alcohol-based oral rinse", "B": "Permethrin hair wash", "C": "Colistin nebulized aerosol", "D": "Chlorhexidine hand disinfection", "E": "Mupirocin nasal ointment"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A research group from Europe is investigating a potential link between certain lifestyle risk factors and the development of potentially fatal renal disease. They designed a cohort study that included 68 individuals: 34 exposed and 34 unexposed to given risk factors, who were followed up for 4 years in total. During this time, the renal disease of interest was seen in 6 individuals among the exposed group and 6 individuals among the unexposed group; thus, the risk ratio (RR) of the disease development (exposed vs. unexposed) was 1. During the initial 2 years, there was 1 death in the exposed group, and another death in the unexposed group. A survey administered for the last 2 years of the study showed that the prevalence ratio of disease between exposed and unexposed individuals was in fact 0.5 (at 2 years of follow-up there was only 1 case of the disease in the 34 exposed individuals, with a resulting prevalence of 2.94%; and only 2 cases of the disease in the 34 unexposed individuals, with a resulting prevalence of 5.88%), a value that deviates from the true RR (i.e. 1). For this reason (and to accurately answer the research question), the risk of the disease should be estimated in terms of which of the following?", "answer": "Incidence", "options": {"A": "Incidence", "B": "Prevalence", "C": "Mortality", "D": "Survival rates", "E": "Lethality rates"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 55-year-old male with fever, fatigue, generalized weakness, and bleeding gums for the past 3 weeks presents to his family physician. On exam, he has bilateral submandibular lymphadenopathy and hepatosplenomegaly. CBC demonstrates decreased RBCs and mature WBCs. The patient is referred to an oncologist, and a bone marrow aspiration is performed, demonstrating >20% myeloblasts with Auer rods that are myeloperoxidase positive. What is the most likely chromosomal translocation that is responsible for this patient's clinical presentation and lab results?", "answer": "15;17", "options": {"A": "15;17", "B": "9;22", "C": "14;18", "D": "11;14", "E": "8;14"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 59-year-old man with Parkinson disease is brought to the emergency department 1 hour after he had a syncopal episode. Over the past two weeks, the patient has felt light-headed upon standing and has noticed that his legs have been swollen. He was started on a medication for early symptoms of Parkinson disease one month ago. Vital signs show blood pressure 114/70 mm Hg when supine and 92/38 mm Hg upon standing. Examination of the lower extremities shows a lacy, purple rash and 2+ pitting edema. Neurologic examination shows an ataxic gait. The physician decreases the dose of medication. The patient is most likely experiencing adverse effects caused by a drug that works through which of the following mechanisms of action?", "answer": "Increased dopamine release from central neurons", "options": {"A": "Increased dopamine release from central neurons", "B": "Inhibition of acetylcholine activity in the basal ganglia", "C": "Selective inhibition of monoamine oxidase type B", "D": "Decreased peripheral conversion of levodopa to dopamine", "E": "Inhibition of central methylation of dopamine"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 50-year-old woman presents to her primary care physician for muscle weakness. Her symptoms have progressively worsened over the course of several months, where she has experienced difficulty getting up from a chair, climbing the stairs, and placing her groceries on the top shelves of her kitchen. She also reports feeling tired lately and is unsure when this began. Physical examination is notable for muscle weakness in the deltoids and hip flexors with 2+ biceps, triceps, patellar, and ankle tendon reflexes. Laboratory testing demonstrates a creatine kinase level of 4,200 U/L (normal is 10-70 U/L), lactate dehydrogenase level of 150 U/L (normal is 45-90 U/L), and thyroid-stimulating hormone level of 1.5 µU/mL (normal is 0.5-5.0 µU/mL). Which of the following is the best initial treatment for this patient?", "answer": "Prednisone", "options": {"A": "Azathioprine", "B": "Intravenous immunoglobulin", "C": "Physostigmine", "D": "Prednisone", "E": "Thyroxine"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 22-year-old woman comes to the physician because of a 5-kg (11-lb) weight gain and hair loss over the past 4 months. Menarche occurred at the age of 12 years and menses occurred at irregular intervals until she stopped having periods 2 months ago. She is 165 cm (5 ft 5 in) tall and weighs 82 kg (180 lb); BMI is 30 kg/m2. Physical examination shows a receding hairline and hair loss over the vertex of the head. Serum studies show:\nThyroid-stimulating hormone 2 μU/mL\nLuteinizing hormone 32 mIU/mL\nProlactin 11 ng/mL\nUrine pregnancy test is negative. Withdrawal bleeding occurs after a progestin challenge test. The most likely cause of amenorrhea in this patient is an increase in production of which of the following hormones?\"", "answer": "Estrogen in adipose tissue", "options": {"A": "Progesterone in corpus luteum", "B": "Androgens in the adrenal gland", "C": "Estrogen in adipose tissue", "D": "Follicle stimulating hormone in the adenohypophysis", "E": "Dopamine in the hypothalamus"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 70-year-old man with chronic myopia comes to the physician because of a 4-month history of difficulty seeing distant objects, especially at night, despite wearing glasses. Examination shows bilateral narrowing of peripheral visual fields, cupping of the optic discs, and elevated intraocular pressure. Gonioscopy shows no abnormalities. He is prescribed a drug. At a follow-up examination several months later, intraocular pressure is normal, but darkening of the iris and an increase in the length of the eyelashes is observed. Which of the following drugs was most likely prescribed?", "answer": "Latanoprost", "options": {"A": "Timolol", "B": "Acetazolamide", "C": "Pilocarpine", "D": "Apraclonidine", "E": "Latanoprost"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 3-week-old female presents with her parents to her pediatrician for a routine visit. The parents report that the child is sleeping in regular two-hour intervals and feeding and stooling well. They are concerned because they have on occasion noticed a “swelling of the belly button.” Cord separation occurred at seven days of age. The parents report that the swelling seems to come and go but is never larger than the size of a blueberry. They deny any drainage from the swelling. On physical exam, the child is in no acute distress and appears developmentally appropriate for her age. Her abdomen is soft and non-tender with a soft, 1 cm bulge at the umbilicus. The bulge increases in size when the child cries and can be easily reduced inside the umbilical ring without apparent pain.\n\nWhich of the following is the best next step in management?", "answer": "Expectant management", "options": {"A": "Expectant management", "B": "Histopathologic evaluation", "C": "Thyroid hormone replacement", "D": "Elective surgical management", "E": "Immediate surgical management"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 25-year-old man presents to the emergency department after a motor vehicle collision. He is currently complaining of chest pain and shortness of breath and seems rather confused. His temperature is 97.7°F (36.5°C), blood pressure is 94/54 mmHg, pulse is 170/min, respirations are 12/min, and oxygen saturation is 90% on room air. A 14-gauge needle is placed in the 2nd intercostal space on the patient’s left, and his blood pressure increases to 104/74 mmHg and his pulse decreases to 100/min. Which of the following is the best next intervention for this patient?", "answer": "Tube thoracostomy", "options": {"A": "Chest radiograph", "B": "Pericardiocentesis", "C": "Supportive therapy and observation", "D": "Thoracotomy", "E": "Tube thoracostomy"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 13-year-old girl presents with a rash on her left hand and forearm. She went hiking with friends the day before yesterday and awoke this morning to find her hand and forearm red and itchy. She denies any swelling of the face or throat, difficulty breathing, dizziness, or palpitations. She has no significant past medical history or known allergies. She is afebrile and her vital signs are within normal limits. On physical examination, there are multiple erythematous papules and fluid-filled vesicles in a linear pattern on her left hand and forearm as shown in the exhibit (see image). Which of the following is the best course of treatment for this patient?", "answer": "Topical clobetasol", "options": {"A": "Oral prednisone", "B": "Topical clobetasol", "C": "Topical tacrolimus", "D": "Phototherapy", "E": "Azathioprine"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 12-year-old boy is brought to the physician for multiple bruises. He has fallen multiple times over the past 4 months and has difficulty walking without assistance. His speech is slow and difficult to understand. Neurological examination shows bilateral nystagmus, decreased muscle strength, 1+ reflexes bilaterally, and a wide-based gait with irregular and uneven steps. His proprioception and vibration senses are absent. The remainder of the examination shows kyphoscoliosis and foot inversion with hammer toes. This patient is most likely to die from which of the following complications?", "answer": "Heart failure", "options": {"A": "Renal cell carcinoma", "B": "Heart failure", "C": "Posterior fossa tumors", "D": "Hypoglycemia", "E": "Aspiration pneumonia\n\""}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 28-year-old nulligravid woman comes to the physician for a routine health maintenance examination. Upon questioning, she reports that she and her husband have been trying to conceive for more than 1 year; they have unprotected sexual intercourse 3–4 times per week. Recently, she has not been enjoying sexual intercourse with her husband because of painful penetration. She also reports episodic back and pelvic pain over the past 6 months that lasts for 2–3 days; she has missed several days of work each month because of the pain. Menarche was at the age of 13 years, and menses occur at 26–28 day intervals. Pelvic examination shows a normal-appearing vulva and vagina. There is rectovaginal tenderness. Ultrasonography of the pelvis shows a retroverted normal-sized uterus. Further evaluation is most likely to show which of the following findings?", "answer": "Reddish-black peritoneal lesions on laparoscopy", "options": {"A": "Endometrial tisssue within the myometrium on biopsy", "B": "Multiple bilateral ovarian cysts on ultrasonography", "C": "Reddish-black peritoneal lesions on laparoscopy", "D": "Concentric, solid myometrial tumors on MRI", "E": "Intracellular organisms on endocervical culture\n\""}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 2-year-old Caucasian male presents with recurrent diaper rash and oral thrush. He has also experienced recurrent episodes of otitis media from repeat Streptoccous pneumoniae. He notably has reduced T and B cell counts. What disease is the child suffering from?", "answer": "Severe combined immunodeficiency", "options": {"A": "X-linked agammaglobulinemia", "B": "Isolated IgA deficiency", "C": "Severe combined immunodeficiency", "D": "DiGeorge syndrome", "E": "MHC class II deficiency"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 42-year-old primigravida woman presents to her gynecologist for a routine prenatal visit at 11 weeks of gestation. Her pregnancy has been uneventful so far. She denies smoking, using alcohol, or any illicit drugs. Past medical history is significant for Hashimoto’s thyroiditis which is well-controlled with levothyroxine. Her blood pressure is 110/70 mm Hg, a heart rate of 95/min, a respiratory rate of 20/min, and a temperature of 36.4°C (97.5°F). Physical examination is unremarkable. A transvaginal ultrasound reveals increased nuchal translucency. Laboratory studies show decreased levels of PAPP-A and increased levels of β-hCG. If the pregnancy is continued to term, the child is at an increased risk of developing which of the following conditions?", "answer": "Alzheimer’s disease", "options": {"A": "Vaginal adenosis", "B": "Huntington disease", "C": "Alzheimer’s disease", "D": "Ebstein anomaly", "E": "Ulcerative colitis"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "An 18-month-old boy is brought to the emergency department by his babysitter because of lethargy and fever for 3 hours. He has not fully recovered from a middle ear infection that started a few days ago. The parents cannot be reached for further information. His temperature is 39.1°C (102.3°F). Physical examination shows nuchal rigidity. A pathogen is isolated from the patient's cerebrospinal fluid that does not grow on regular blood agar plate but produces colonies when cocultured with Staphylococcus aureus. Vaccination against the causal pathogen of this patient's current disease is most likely to also prevent which of the following conditions?", "answer": "Epiglottitis", "options": {"A": "Bacterial rhinosinusitis", "B": "Influenza", "C": "Epiglottitis", "D": "Chancroid", "E": "Impetigo"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 20-month-old boy is brought to the physician for the evaluation of intellectual and behavioral abnormalities and abnormal movements of his extremities. His mother reports that he often hits his head and limbs against furniture. He is unable to walk without support and speaks in unclear 2-word phrases. Examination shows multiple bruises on the forehead and several healing wounds over the fingers. There is increased muscle tone in all extremities. Laboratory studies show an increased serum uric acid concentration. The serum concentration of which of the following substances is most likely to also be increased in this patient?", "answer": "Phosphoribosyl pyrophosphate", "options": {"A": "Phenylalanine", "B": "Deoxyadenosine trisphosphate", "C": "Branched-chain amino acids", "D": "Phosphoribosyl pyrophosphate", "E": "Cytosine monophosphate"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 24-year-old man presents to the office for a physical exam and drug screening requested by his parole officer. He has a history of multiple run-ins with the law, including theft, destruction of property, and assault and battery. Patient confesses that he has always been the 'problem child' in his home and always got into trouble with authority figures. Past medical records reveal testimonies from his mother describing episodes of physically aggressive behavior in school starting at before 12. Although a single parent, his mother states there were no stressful changes or issues at home. Today's urine toxicology screens are negative. Which of the following is most likely this patient’s diagnosis?", "answer": "Antisocial personality disorder", "options": {"A": "Substance use-related aggression", "B": "Oppositional defiant disorder", "C": "Conduct disorder", "D": "Antisocial personality disorder", "E": "Borderline personality disorder"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 47-year old woman is referred to a nephrologist due to hematuria over the last week and lower extremity edema. She first noticed her feet and legs would swell in the mornings about 2 weeks ago. Her past medical history is significant for systemic lupus erythematosus for the past 24 years. This causes her mild joint and muscle pain on most day and she manages her symptoms with ibuprofen and acetaminophen. Today, her heart rate is 90/min, the respiratory rate is 17/min, the blood pressure is 140/90 mm Hg, and the temperature is 37.1°C (98.8°F). Urine analysis shows 6-10 dysmorphic RBCs per high powered field and occasional cellular casts. Serum creatinine is 2.4 mg/dL and a 24 hour urine collection reveals 550mg of excreted protein. A kidney biopsy shows findings consistent with diffuse proliferative glomerulonephritis. Which of the following is the best initial therapy for this patient?", "answer": "Cyclophosphamide and prednisolone", "options": {"A": "Methotrexate and folic acid", "B": "Hydroxychloroquine", "C": "Intravenous immunoglobulin", "D": "Plasmapheresis", "E": "Cyclophosphamide and prednisolone"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 6-year-old girl presents to your clinic two weeks after receiving a routine immunization in preparation for a trip overseas. Periorbital edema is present on exam, and 24 hour urine collection shows excretion of 4.3 grams of protein/day. Which pathological change would likely be seen on microscopy?", "answer": "Podocyte effacement on electron microscopy", "options": {"A": "Linear IgG deposition on light microscopy", "B": "IgA-immune complexes in the mesangium on electron microscopy", "C": "“Tram-track” appearance on light microscopy", "D": "Subepithelial deposits with “spike and dome” appearance on electron microscopy", "E": "Podocyte effacement on electron microscopy"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 9-year-old girl is brought to the physician by her father for evaluation of intermittent muscle cramps for the past year and short stature. She has had recurrent upper respiratory tract infections since infancy. She is at the 5th percentile for weight and 10th percentile for height. Physical examination shows nasal polyps and dry skin. An x-ray of the right wrist shows osteopenia with epiphyseal widening. Which of the following sets of laboratory findings is most likely in this patient's serum?\n $$$ Calcium %%% Phosphorus %%% Parathyroid hormone %%% Calcitriol $$$", "answer": "↓ ↓ ↑ ↓", "options": {"A": "↓ ↓ ↑ ↓", "B": "↓ ↑ ↑ ↓", "C": "↓ ↑ ↓ ↓", "D": "↑ ↓ ↑ ↑", "E": "Normal ↓ ↑ ↓"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 24-year-old medical student presents to urgent care with cough and rhinorrhea. He has been learning about HIV and immunosuppression in medical school, and he is worried that he is seriously ill. He has no significant medical history, and he is sexually active with his girlfriend. He consumes alcohol on weekends but does not use tobacco or other recreational drugs. He candidly reports that, in microbiology lab, he cultured his own sputum on Sabouraud agar, and Candida grew on the agar. Examination of the oropharynx does not show any abnormalities. You perform a nasal viral swab, which confirms that he has a rhinovirus infection. Which of the following is the most likely explanation for his positive Candida culture?", "answer": "Benign Candida colonization", "options": {"A": "HIV virus infection", "B": "Squamous oral cancer", "C": "Xerostomia", "D": "Surreptitious drug use", "E": "Benign Candida colonization"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 57-year-old woman comes to her physician with a persistent cough. She has observed an increase in the frequency of her cough over the past few months and also the production of yellowish sputum on several occasions. She says that sputum production is greater in the morning compared to the rest of the day. She has been a chain smoker for about 35 years now, smoking close to 3 packs a day. She has never had the will to quit. Over the last 2 years, she has had this cough and doesn't recall being free of it for 3 months at a stretch. On examination, there is a slight expiratory wheeze in the lower lung fields. Her respiratory rate is 18/min, pulse is 85/min, and blood pressure is 110/70 mm Hg. Her forced expiratory volume in the first second is 83% at this time. Her FEV1/FVC post-bronchodilator ratio is 0.65. Based on these findings, her physician recommends that she quit smoking. She is also advised to take pneumococcal and influenza vaccinations over the next few months. Which of the following medications would be most appropriate to assist the patient with her symptoms at this time?", "answer": "Albuterol", "options": {"A": "Salmeterol", "B": "Albuterol", "C": "Fluticasone", "D": "Doxycycline", "E": "Prednisone"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 56-year-old woman presents to her primary care physician for dizziness. She says that her symptoms began approximately 1 month prior to presentation and are associated with nausea and ringing of the ears. She describes her dizziness as a spinning sensation that has a start and end and lasts approximately 25 minutes. This dizziness is severe enough that she cannot walk or stand. Her symptoms are fluctuating, and she denies any tunnel vision or feelings of fainting. However, she has abruptly fallen to the ground in the past and denied losing consciousness. Medical history is significant for a migraine with aura treated with zolmitriptan, type 2 diabetes managed with metformin, and hypertension managed with lisinopril. Her blood pressure is 125/75 mmHg, pulse is 88/min, and respirations are 16/min. On physical exam, when words are whispered into her right ear, she is unable to repeat the whispered words aloud; however, this is normal in the left ear. Air conduction is greater than bone conduction with Rinne testing, and the sound of the tuning fork is loudest in the left ear on Weber testing. Which of the following is most likely the diagnosis?", "answer": "Meniere disease", "options": {"A": "Benign paroxysmal positional vertigo", "B": "Meniere disease", "C": "Migraine", "D": "Transient ischemic attack", "E": "Vestibular neuritis"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 3086-g (6-lb) male newborn is delivered at 39 weeks' gestation to a 29-year-old woman. Initial examination shows micrognathia, a broad nasal bridge, short philtrum, and a cleft palate. Intermittent muscle spasms are seen predominantly in the hands and feet. A harsh systolic murmur is heard over the lower left sternal border. Which of the following is the most likely cause of this infant’s symptoms?", "answer": "Deletion in chromosome 22", "options": {"A": "Deletion in chromosome 7", "B": "Deletion in chromosome 22", "C": "Nondisjunction of chromosome 21", "D": "Nondisjunction of chromosome 13", "E": "Deletion in chromosome 5"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 37-year-old woman comes to the emergency department because her eyes have had a yellow discoloration and she has had dark urine for the past 3 days. She has also had fever, itching, and severe fatigue. She reports having symptoms of the stomach flu a week ago, which resolved with over-the-counter medication. She does not have diarrhea but says her stools are whitish in appearance. She has no personal history of serious illness. She does not smoke and drinks an average of 2 beers on weekends. She does not use illicit drugs. She has been sexually active with the same partner for 12 years and uses condoms consistently. She works as a flight attendant for an international airline. She appears ill. Her temperature is 39.3°C (102.7°F), pulse is 64/min, and blood pressure is 132/82 mm Hg. Examination shows scleral icterus, excoriation marks over her extremities, and parched lips. The liver is tender on palpation; there is no splenomegaly. Cardiopulmonary examination is normal. Laboratory studies show:\nHemoglobin 11.6 g/dL\nLeukocyte count 10,300/mm3\nPlatelet count 256,000/mm3\nESR 19 mm/hr\nProthrombin time 13 seconds\nSerum\nUrea nitrogen 28 mg/dL\nGlucose 89 mg/dL\nCreatinine 0.7 mg/dL\nBilirubin\nTotal 8 mg/dL\nDirect 4 mg/dL\nALP 80 U/L\nAST 312 U/L\nALT 569 U/L\nAn ultrasound of the abdomen shows no abnormalities. Serum studies are most likely to show which of the following findings?\"", "answer": "Anti-HAV IgM", "options": {"A": "Anti-mitochondrial antibodies", "B": "Perinuclear anti-neutrophil cytoplasmic antibodies", "C": "Anti-HAV IgM", "D": "Anti-HEV IgG", "E": "HBsAg"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 27-year-old man presents with diarrhea, fatigue and weight loss. He says he has been having occasional loose stools and abdominal pain for the past month, but he did not seek any medical attention because of work deadlines. He says the diarrhea is associated with cramping lower abdominal pain and an urgency to defecate. His stool is loose, occasionally blood-tinged, and contains mucus. He also says he feels fatigued and has lost 11 kg (24 lb) over the last 2 months. The patient denies any fever, sick contacts, or a history of recent travel. No significant past medical history. Family history is significant for colon cancer in his father, who died at the age of 50. On physical examination, the patient has generalized pallor. Abdominal exam reveals mild tenderness to palpation in the left lower quadrant. Laboratory investigations reveal microcytic anemia with an elevated ESR. A colonoscopy with biopsy is performed, which shows inflammation of the sigmoid colon and rectum. Biopsy shows a predominantly lymphoid infiltration of the mucosa and submucosa with multiple crypt abscesses. No evidence of granulomatous disease. What is the mechanism of action of the drug which typically induces remission of this patient’s most likely condition?", "answer": "Inhibition of prostaglandins and inflammatory cytokines", "options": {"A": "Inhibition of prostaglandins and inflammatory cytokines", "B": "Antibody against tumor necrosis factor", "C": "Inhibition of cellular metabolism", "D": "Acts on intestinal smooth muscle to decrease motility", "E": "Suppression of polymorphonuclear cell migration"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 61-year-old woman presents to your office complaining of mild fatigue and weight loss over the past 6 months. She states she has felt generally unwell and has had decreased appetite during this time frame. Her temperature is 98.1°F (36.7°C), blood pressure is 122/80 mmHg, pulse is 88/min, respirations are 16/min, and oxygen saturation is 98% on room air. Physical exam reveals splenomegaly and a nontender abdomen. A complete blood count with differential shows the following:\n\nHemoglobin: 10 g/dL\nHematocrit: 30%\nLeukocyte count: 166,500/mm^3\nSegmented neutrophils 92%\nLeukocyte alkaline phosphatase: Low\nPlatelet count: 92,000/mm^3\n\nA bone marrow biopsy is performed demonstrating infiltration with a large number of normal-appearing neutrophils. Which of the following translocations is likely to be seen in this patient?", "answer": "t(9;22)", "options": {"A": "t(8;14)", "B": "t(9;22)", "C": "t(12;21)", "D": "t(14;17)", "E": "t(15;17)"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 44-year-old homeless man is brought to the emergency department after he was arrested when found intoxicated in someone's garage. The patient is acutely altered and is covered in urine, stool, and vomit. His temperature is 97.6°F (36.4°C), blood pressure is 104/64 mmHg, pulse is 130/min, respirations are 19/min, and oxygen saturation is 98% on room air. The patient is aroused with pain and begins answering basic questions. He states his vision is blurry and he can't see anything. Laboratory values are ordered as seen below.\n\nSerum:\nNa+: 141 mEq/L\nCl-: 102 mEq/L\nK+: 4.4 mEq/L\nHCO3-: 14 mEq/L\nBUN: 25 mg/dL\nGlucose: 99 mg/dL\nCreatinine: 1.4 mg/dL\nCa2+: 10.2 mg/dL\n\nWhich of the following is the most appropriate initial treatment of this patient?", "answer": "Inhibition of alcohol dehydrogenase", "options": {"A": "Glutathione formation", "B": "Inhibition of alcohol dehydrogenase", "C": "Inhibition of aldehyde dehydrogenase", "D": "Muscarinic antagonism", "E": "Removal via dialysis"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 32-year-old construction worker is brought to the Emergency Department after a block of concrete crushed his right leg. His coworkers tried to remove the block, but it was not possible until firemen arrived on the scene 30 minutes after the incident. His personal medical history is unremarkable. Upon admission his vitals were stable. On physical examination the man is unconscious. His right leg is deformed with lacerations and hematomas. There are at least two fractures and several areas of the muscle appear pulpified. Distal right pulses are absent. An X-ray of the right leg reveals several displaced fractures of the tibia and fibula. Blood samples and a urine specimens are sent to the lab for analysis. Which of the following laboratory abnormalities would you expect to find in this patient?", "answer": "Fractional excretion of sodium (FeNa+) > 2%", "options": {"A": "Fractional excretion of sodium (FeNa+) > 2%", "B": "Urine osmolality > 500 mOsmol/kg", "C": "Hypercalcemia", "D": "Red-tinted plasma", "E": "Elevated haptoglobin"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 42-year-old primigravida woman goes into labor at 37 weeks. After several hours of labor, a boy is born with multiple physical abnormalities including cleft palate, micrognathia, and low-set ears. Imaging reveals an absence of the thymic shadow. Which of the following is the most likely cause of the patient’s condition?", "answer": "Microdeletion of the long arm of chromosome 22", "options": {"A": "Microdeletion of the long arm of chromosome 22", "B": "Microdeletion of the long arm of chromosome 7", "C": "Microdeletion of the short arm of chromosome 5", "D": "Trisomy 18", "E": "Adenosine deaminase deficiency"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 20-year-old woman presents following a seizure 2 hours ago. The patient's roommate describes seeing the patient suddenly 'freeze', collapse, and start having jerky movements involving her entire body. The patient says she can not recall the episode but does remember 'seeing stars' before losing consciousness. She remembers being confused about where she was soon after the seizure and had urinated in her clothes when she regained consciousness. A persistent headache has troubled her since the seizure for which she took acetaminophen before coming to the hospital. Her past medical history is unremarkable. She denies alcohol and drug use. The physician starts her on an antiepileptic drug that acts in the motor cortex by blocking repeated activation of voltage-gated sodium channels and is also used in status epilepticus. When this drug is used long-term, which of the following complications can develop?", "answer": "Drug-induced SLE", "options": {"A": "Drug dependence", "B": "Drug-induced SLE", "C": "Renal failure", "D": "Glaucoma", "E": "Liver failure"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 68-year-old man presents to his primary care physician for pain in his feet. The patient states that it is very painful for him to walk around, and he has significant pain in his right and left toes. The patient has a past medical history of obesity, type II diabetes mellitus, anxiety, depression, COPD, and a 30 pack-year smoking history. The patient’s current medications include lisinopril, hydrochlorothiazide, insulin, metformin, fluoxetine, clonazepam, albuterol, home oxygen, varenicline, and fish oil and he is compliant with all medications. On physical exam, the patient’s toes appear pale and dirty. When inspecting his toes, shallow wounds with a pale base devoid of granulation tissue can be appreciated. The patient has decreased pinprick sensation in his lower extremities bilaterally. Pulmonary exam is notable for a prolonged expiratory phase. Which of the following findings is most likely to be found in this patient?", "answer": "Calf pain after walking moderate distance", "options": {"A": "Bipedal edema", "B": "Decreased immunity", "C": "Increased reflexes of the lower extremities", "D": "Loss of vibration sensation in the lower extremities", "E": "Calf pain after walking moderate distance"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 16-year-old man is brought to the emergency department for left arm pain. Per the patient, he was playing at his high-school football game when a member of the opposing team tackled him from behind, which resulted in him landing on his left arm. He felt a “popping” sensation and immediate, sharp pain at his left shoulder. The patient is in mild distress and holds his arm against his abdomen. Physical examination demonstrates limited abduction secondary to pain and reduced muscle tone over the shoulder. What additional finding would you expect from this patient?", "answer": "Loss of sensation over the lateral arm", "options": {"A": "Loss of sensation over the dorsal hand", "B": "Loss of sensation over the medial 1 1/2 fingers", "C": "Loss of sensation over the lateral 3 1/2 fingers", "D": "Loss of sensation over the lateral arm", "E": "Loss of sensation over the lateral forearm"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 68-year-old woman is brought to the emergency room because of pain in her right shoulder after falling down the stairs in her apartment. She has a history of postmenopausal osteoporosis. Her current medications are alendronate, vitamin D, and calcium supplementation. Physical examination shows shortening of the right arm as well as tenderness and swelling over the right shoulder. The range of motion of the right arm is limited by pain. An x-ray of the right shoulder shows a fracture of the surgical neck of the humerus. Which of the following movements is most likely to be impaired in this patient?", "answer": "Arm abduction", "options": {"A": "Wrist extension", "B": "Elbow flexion", "C": "Arm abduction", "D": "Thumb adduction", "E": "Wrist flexion\n\""}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A hematologist has found a historical hemocytometer used during the 1960s. Out of curiosity, he decides to obtain platelet counts from his brother, who has idiopathic thrombocytopenic purpura (ITP), with both the historical hemocytometer and a modern automated CBC analyzer. The platelet counts of repeated measurements are shown in ascending order:\nHistorical hemocytometer 55,000 57,000 62,000 76,000 77,000 82,000 92,000 Mean: 72,000\nModern automated CBC analyzer 71,000 71,000 72,000 72,000 73,000 74,000 74,000 Mean: 72,000\nIf the measurements on a modern automated CBC analyzer are considered accurate, which of the following conclusions can be drawn about the historical hemocytometer?\"", "answer": "Test lacks precision", "options": {"A": "Test lacks accuracy", "B": "Test lacks validity", "C": "Test lacks specificity", "D": "Test lacks precision", "E": "Test lacks sensitivity"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 9-year-old female child whose family recently emigrated from Afghanistan presents to the county hospital with difficulty swallowing and generalized muscle rigidity. Her parents note that although she is in severe pain she always appears to be smiling. After getting a detailed history from the parents, the residents comes to the conclusion that the child's clinical presentation is due to a lack of immunizations and a deep wound on her knee resulting from a fall six days ago. Which of the following is the mechanism of action of the toxin causing this child's symptoms?", "answer": "Preventing release of GABA by cleaving of synaptobrevin 2", "options": {"A": "Inhibiting protein synthesis via ADP-ribosylation of elongation factor 2", "B": "Overactivating adenylate cyclase by ADP-ribosylation of the Gs alpha subunit", "C": "Overactivating adenylate cyclase by disabling the Gi subunit", "D": "Preventing release of GABA by cleaving of synaptobrevin 2", "E": "Preventing release of acetycholine by cleaving SNAP-25"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 49-year-old obese man presents to the emergency department with a fever and a cough productive of bloody sputum. He has also been waking up at night frequently, which he attributes to sweating while asleep. He is also proud of recently losing some weight but denies actively trying to do so. He says that he has had these symptoms intermittently for the last several years but has not consistently sought treatment because his housing has been transient with periods of homelessness. He is started on a course of therapy and leaves against medical advice before his physician is able to explain the medications. He returns two days later because he is concerned that his eyes are bleeding. The area of the lung most likely affected by this patient's condition has which of the following characteristics?", "answer": "Low perfusion, low ventilation, high V/Q ratio", "options": {"A": "High perfusion, high ventilation, high V/Q ratio", "B": "High perfusion, high ventilation, low V/Q ratio", "C": "Low perfusion, high ventilation, high V/Q ratio", "D": "Low perfusion, low ventilation, high V/Q ratio", "E": "Low perfusion, low ventilation, low V/Q ratio"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 66-year-old male presents to clinic for a blood glucose level of 169 mg/dL taken at a local pharmacy. He is a farmer in rural Alabama and has not seen a doctor for decades. He wants to be in excellent shape prior to his trip to visit his daughter at college. His past medical history and family history are unknown, and he does not take any medications. His diet consists of pork products and he does not smoke. His temperature is 99.5°F (37.5°C), pulse is 100/min, blood pressure is 169/90 mmHg, respirations are 18/min, and oxygen saturation is 97% on room air. The patient is started on metformin, lisinopril, and a guided exercise program. Lab results are below:\n\nSerum:\nNa+: 145 mEq/L\nCl-: 100 mEq/L\nK+: 4.9 mEq/L\nHCO3-: 24 mEq/L\nBUN: 18 mg/dL\nGlucose: 211 mg/dL\nCreatinine: 1.0 mg/dL\nCa2+: 10.0 mg/dL\n\nHe returns from his trip, complaining of cough. He denies any other symptoms. His temperature is 99.5°F (37.5°C), pulse is 101/min, blood pressure is 160/85 mmHg, respirations are 18/min, and oxygen saturation is 98% on room air. Repeat lab results are below:\n\nSerum:\nNa+: 145 mEq/L\nCl-: 100 mEq/L\nK+: 5.3 mEq/L\nHCO3-: 24 mEq/L\nBUN: 22 mg/dL\nGlucose: 169 mg/dL\nCreatinine: 1.2 mg/dL\nCa2+: 10.1 mg/dL\n\nWhat is the next best step in management?", "answer": "Switch blood pressure medication to losartan", "options": {"A": "Switch blood pressure medication to losartan", "B": "Switch blood pressure medication to hydrochlorothiazide", "C": "Chest radiograph", "D": "Azithromycin", "E": "Loratadine"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 25-year-old woman presents to her primary care physician for her annual physical exam. Her prior medical history is significant for seasonal allergies and a broken arm at age 12 that was treated in a long arm cast. She has not had any major illnesses in the previous year and does not currently have any major complaints. On physical exam her blood pressure is found to be 152/95 mmHg. Laboratory findings reveal elevated levels of renin and aldosterone. Given her elevated blood pressure, she is prescribed captopril; however, 1 week later she presents to the emergency department with hypertensive urgency. At that point captopril is immediately stopped. Which of the following is the most likely cause of this patient's disorder?", "answer": "Bilateral fibromuscular dysplasia", "options": {"A": "Bilateral fibromuscular dysplasia", "B": "Conn syndrome", "C": "Renal artery atherosclerosis", "D": "Renin secreting tumor", "E": "Unilateral fibromuscular dysplasia"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "An investigator is analyzing the serum calcium and parathyroid hormone levels of 100 patients. A scatter plot of the findings is shown. Which of the following is a possible explanation for the group marked with the letter E?", "answer": "Lymphoma", "options": {"A": "Lymphoma", "B": "End-stage kidney disease", "C": "Celiac disease", "D": "Thyroidectomy", "E": "Multiple endocrine neoplasia"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 56-year-old male is admitted to the emergency department with sudden onset of pain, left-sided scrotal swelling, and nausea. The patient states that the symptoms started three hours ago after he lifted up a heavy pack. He says that the swelling had been intermittently present for several years already and was most prominent when physically straining or coughing, but it had never been painful. Past medical history is unremarkable. Patient reports a 26-pack-year history of smoking. Vital signs are as follows: blood pressure 150/90 mm Hg, heart rate 85/min, respiratory rate 14/min, and temperature 37.8℃ (100℉). BMI is 32.9 kg/m2. Patient’s respiratory and cardiovascular exams are within normal limits. The abdomen is moderately distended. There is a tender erythematous scrotal swelling on the left, which cannot be manually reduced. Which of the following tests should be performed to confirm the diagnosis in this patient?", "answer": "No further tests are needed", "options": {"A": "Ultrasonography", "B": "No further tests are needed", "C": "Fine needle biopsy", "D": "Laparoscopy", "E": "CT scan"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 6-year-old boy presents to a pediatrician for initial evaluation. He was recently adopted from abroad and his parents want to establish care in the United States. His medical history is unclear and there are no records on any family history. On presentation, he is found to fall below the 5th percentile in height for his age with shortened 4th and 5th digits. Physical exam reveals wrist spasms when his blood pressure is taken. Radiographs reveal decreased bone mineral density and several healing fractures. Which of the following mechanisms is most likely associated with this patient's presentation?", "answer": "Resistance to effects of parathyroid hormone", "options": {"A": "Decreased production of parathyroid hormone", "B": "Inadequate intake of vitamin D", "C": "Malabsorption of nutrients", "D": "Mutation on chromosome 22", "E": "Resistance to effects of parathyroid hormone"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 12-year-old boy is brought to the emergency department with a 2-month history of increasing difficulty with physical activity. Specifically, he says that he gets short of breath quickly with exertion even though he used to participate in all activities without a problem. When asked, he endorses sometimes coughing up flecks of blood. His past medical history is unclear because he was recently adopted from abroad and has not yet established care. Physical exam reveals blue discoloration of his lips and fingernails as well as a holosystolic murmur best heard at the lower left sternal border. Which of the following physiologic mechanisms is primarily responsible for this patient's current presentation?", "answer": "Pulmonary artery hypertension", "options": {"A": "Increasing size of ventricular septal defect", "B": "Left ventricular outflow tract obstruction", "C": "New atrial septal defect", "D": "Pulmonary artery hypertension", "E": "Recently closed ventricular septal defect"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A scientist isolates the rough endoplasmic reticulum from HeLa cells. He performs a northern blot to isolate nucleic acid sequences of interest. Which of the following molecules make up part of the structure that was separated?", "answer": "Ribosomal RNA", "options": {"A": "RNA polymerase", "B": "Transfer RNA", "C": "Ribosomal RNA", "D": "Mitochondrial RNA", "E": "Small nuclear RNA"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 14-month-old girl is brought to the pediatrician after her parents noticed her being increasingly irritable with frequent vomiting for the past 2 weeks. Parents deny any history of fever. They recently immigrated to the country and, unfortunately, the mother did not receive prenatal care during pregnancy due to a lack of health insurance. Physical examination is unremarkable except for a head circumference over 2 standard deviations larger than the mean for her age, and delay in meeting motor developmental milestones. A magnetic resonance imaging (MRI) of her brain shows an enlargement of the posterior fossa, cystic dilation of the 4th ventricle, and hypoplasia of the cerebellar vermis (see image). Which of the following is the most likely diagnosis in this patient?", "answer": "Dandy-Walker malformation", "options": {"A": "Chiari II malformation", "B": "Chiari III malformation", "C": "Dandy-Walker malformation", "D": "Mega cisterna magna", "E": "Klippel Feil syndrome"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 28-year-old woman presents with a 3-year history of recurrent headaches. She says the episodes are typically triggered by hunger, mental stress, physical exertion, and lack of sleep, although many times the trigger is not known. She describes her headaches as unilateral, severe, throbbing, and aggravated by movement. The patient says that each episode usually lasts for 6–24 hours and is often accompanied by nausea, vomiting, and intolerance to light. Which of the following brain regions, if lesioned, would most likely result in no change in this patient’s symptoms?", "answer": "Red nucleus", "options": {"A": "Dorsal raphe nucleus", "B": "Red nucleus", "C": "Locus coeruleus", "D": "Nucleus raphe magnus", "E": "Periaqueductal gray"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 68-year-old man comes to the physician for a routine health maintenance examination. He has had increasing shortness of breath and a productive cough for the past 1 year. He can walk up a flight of stairs without stopping. He has hypertension and his only medication is amlodipine. He has a history of asthma during childhood. He smoked 1 pack of cigarettes daily for 30 years but quit 16 years ago. He used to work at a shipyard and retired 5 years ago. His pulse is 98/min, respirations are 25/min and blood pressure is 134/88 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 93%. Scattered expiratory wheezing and rhonchi are heard throughout both lung fields. Cardiac examination shows no murmurs, rubs, or gallops. Spirometry shows an FEV1:FVC ratio of 63% and an FEV1 of 65% of predicted. His diffusing capacity for carbon monoxide (DLCO) is 40% of predicted. Which of the following is the most likely cause of this patient's findings?", "answer": "Emphysema", "options": {"A": "Asthma", "B": "Congestive heart failure", "C": "Bronchiectasis", "D": "Emphysema", "E": "Asbestosis\n\""}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 9-year-old boy presents to his orthopedic surgeon for ongoing evaluation of his lower extremity deformities. Specifically, his hips have been dislocating over the last year despite bracing in hip-knee-ankle-foot orthoses. He is paralyzed from below the L2 nerve root and has difficulty with both bladder and bowel incontinence. He has had these abnormalities since birth due to a lower back lesion that required surgical closure during infancy. Which of the following substances was most likely elevated in his mother's serum during her pregnancy?", "answer": "Alpha-fetoprotein", "options": {"A": "Alpha-fetoprotein", "B": "Beta-human chorionic growth hormone", "C": "Estriol", "D": "Lecithin", "E": "Sphingomyelin"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "Polymerase chain reaction (PCR) has revolutionized the molecular biology field. PCR allows for amplification of a single piece of genetic material to produce trillions of idential copies. Which of the following is NOT necessary for PCR?", "answer": "Reverse transcriptase", "options": {"A": "Taq polymerase", "B": "Reverse transcriptase", "C": "Primers", "D": "Deoxynucleotide triphosphates", "E": "Target DNA strand"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "An investigator is studying the efficacy of antiviral drugs in infected human cells. Harvested human cells are inoculated onto four cell culture plates. Live varicella-zoster virus (VZV) is administered to cells on two of the culture plates. One healthy and one infected cell set are set aside as controls. In comparison with the control plates, the subsequent application of a guanosine analog to the experimental cell sets induces cell death in the virally infected cells but not in the healthy cells. Which of the following is the most likely mechanism for these findings?", "answer": "Phosphorylation by virally-encoded thymidine kinase", "options": {"A": "Secretion of interferons by virally infected cells", "B": "Alteration of cell membrane permeability", "C": "Mutation of viral DNA polymerase", "D": "Phosphorylation by virally-encoded thymidine kinase", "E": "Inhibition of RNA-dependent DNA polymerase"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 13-year-old boy is brought to the physician because of pain and redness on his back for 2 days. He returned yesterday from a vacation to East Africa with his parents, where he took multiple rides on hot air balloons. His vital signs are within normal limits. Examination shows a tender, nonpruritic, erythematous rash with edema covering the extensor surface of both forearms, the shoulders, and the upper back, with small patches of skin exfoliation. The rash becomes pale when pressed and then rapidly regains color. The remainder of the examination shows no abnormalities. Which of the following is the most appropriate next step in management?", "answer": "Apply aloe vera-based moisturizer\n\"", "options": {"A": "Dress wound with wet gauze", "B": "Administer 2 liters of intravenous fluids", "C": "Apply lidocaine cream", "D": "Apply topical mupirocin", "E": "Apply aloe vera-based moisturizer\n\""}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 55-year-old man comes to the emergency department because of headache, fever, chills, shortness of breath, and abdominal pain for 1 week. He also feels tired and nauseous. He returned from a trip to Botswana 2 weeks ago. He has type 2 diabetes mellitus. He has smoked one pack of cigarettes daily for the past 30 years and drinks a glass of beer daily. His only current medication is metformin. His temperature is 39.3°C (102.8°F), pulse is 122/min, respirations are 28/min, and blood pressure is 109/84 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 94%. Examination shows jaundice. A few scattered inspiratory crackles are heard in the thorax. The liver is palpated 2 cm below the right costal margin. Laboratory studies show:\nHemoglobin 9.2 g/dL\nLeukocyte count 9,400/mm3\nPlatelet count 90,000/mm3\nSerum\nNa+ 137 mEq/L\nCl- 102 mEq/L\nK+ 5.2 mEq/L\nHCO3- 13 mEq/L\nGlucose 69 mg/dL\nLactate dehydrogenase 360 U/L\nCreatinine 0.9 mg/dL\nBilirubin\n_ Total 4.2 mg/dL\n_ Direct 0.8 mg/dL\nAST 79 U/L\nALT 90 U/L\nUrine\nBlood 3+\nProtein trace\nRBC 0–1/hpf\nWBC 1–2/hpf\nArterial blood gas analysis on room air shows a pH of 7.31. Which of the following is the most appropriate next step in management?\"", "answer": "Blood smear", "options": {"A": "Coombs test", "B": "Blood culture", "C": "Chest x-ray", "D": "Blood smear", "E": "Serology"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A population study was conducted to evaluate coronary artery disease in the general population. A cohort of 700 patients underwent coronary angiography to evaluate the geographic distribution of coronary arteries throughout the heart. Which of the following was the most common finding in this cohort?", "answer": "Right coronary artery dominance", "options": {"A": "The SA node is supplied by a branch of the right coronary artery.", "B": "The AV node is supplied by a branch of the right coronary artery.", "C": "Right coronary artery dominance", "D": "The SA node is supplied by a branch of both the right and left coronary artery.", "E": "A SA node is supplied by a branch of the left coronary artery."}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 24-year-old woman comes to the physician because of intermittent episodes of stabbing facial pain for 4 months. The pain occurs over her left cheek, is 9 out of 10 in intensity, radiates towards her mouth, and lasts around half a minute before subsiding. These episodes commonly occur when she washes her face, brushes her teeth, or eats a meal. She does not have visual disturbances, weakness of her facial muscles, or hearing loss. She had a tooth extracted about 2 months ago, but the facial pain has persisted. She has hypothyroidism and vitiligo. Her mother has major depressive disorder. Current medications include levothyroxine and a herbal cream. She appears anxious. Vital signs are within normal limits. Cardiopulmonary examination shows no abnormalities. Neurologic examination shows no focal findings. Which of the following is the most appropriate next step in management?", "answer": "Carbamazepine", "options": {"A": "Amitriptyline", "B": "Microvascular decompression", "C": "Botulinum toxin injection", "D": "Radiofrequency rhizotomy", "E": "Carbamazepine"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 67-year-old man is brought to the emergency department after the sudden onset of dizziness, blurry vision, and a raspy voice. He has type 2 diabetes mellitus, hypercholesterolemia, coronary artery disease, and hypertension. He has smoked two packs of cigarettes daily for 30 years. He drinks three to four beers daily. His current medications include metformin, atenolol, lisinopril, furosemide, and aspirin. His temperature is 36.6°C (98°F), pulse is 85/min, respirations are 18/min, and blood pressure is 142/90 mm Hg. He is alert and oriented to person, place, and time. The pupil on the left is pinpoint. There is ptosis of the left eye. Horizontal nystagmus is present. The gag reflex is diminished. When he stands without support, he falls towards his left side. There is loss of pain and temperature sensation over the left face and right trunk and limbs. Occlusion of which of the following arteries is the most likely cause of this patient's symptoms?", "answer": "Left posterior inferior cerebellar artery", "options": {"A": "Right middle cerebral artery", "B": "Left posterior inferior cerebellar artery", "C": "Left internal carotid artery", "D": "Right internal carotid artery", "E": "Left posterior cerebral artery"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 67-year-old woman with a recently found hepatic carcinoma has been an inpatient for more than a week. During morning rounds, she was abnormally disoriented to time and place along with a shortened attention span. The overnight resident reports that she was coming in and out of this state for the past couple nights. The patient was known to drink often, but reported that she has not consumed alcohol in weeks leading up to her admission. She is not jaundiced and has no metabolic imbalance upon laboratory tests. What is the most likely cause of her recent mental impairment?", "answer": "Delirium", "options": {"A": "Delirium", "B": "Substance abuse", "C": "Brain metastasis", "D": "Delirium tremens", "E": "Dementia"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 51-year-old man comes to the physician because of recurrent episodes of dizziness, tinnitus, and hearing loss on the left side for 6 weeks. These episodes last for hours at a time and are associated with the sensation that the room is spinning. He has no history of major medical illness and takes no medications. Examination shows horizontal nystagmus to the left. Weber test shows lateralization to the right ear. The Rinne test is positive bilaterally. Which of the following is the most likely cause of this patient's symptoms?", "answer": "Endolymphatic hydrops", "options": {"A": "Dislodged otoliths", "B": "Inflammation of the vestibular nerve", "C": "Acoustic neuroma", "D": "Endolymphatic hydrops", "E": "Posterior inferior cerebellar artery infarction"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 37-year-old farmer presents to the emergency department with acute onset of complaints of diarrhea, excessive tearing, and increased saliva production. He is concerned that he is dehydrated, as he has also been urinating with increased frequency over the past several hours. His temperature is 97.6°F (36.4°C), blood pressure is 111/64 mmHg, pulse is 60/min, respirations are 10/min, and oxygen saturation is 98% on room air. Physical exam is significant for a moderately agitated and diaphoretic man who demonstrates pinpoint pupils. Which of the following is the most appropriate next step in management?", "answer": "Atropine", "options": {"A": "Atropine", "B": "Diphenhydramine", "C": "Naloxone", "D": "Physostigmine", "E": "Transcutaneous pacing"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 54-year-old woman comes to the emergency department because of sharp chest pain and shortness of breath for 1 day. She has been coughing intermittently, which worsens the pain. She has osteoporosis, for which she takes raloxifene. Arterial blood gas analysis on room air shows:\npH 7.52\nPCO2 25 mm Hg\nPO2 65 mm Hg\nO2 saturation 92%\nPhysical examination is most likely to show which of the following findings?\"", "answer": "Unilateral swelling of the leg", "options": {"A": "Unilateral swelling of the leg", "B": "Increased anteroposterior diameter of the thorax", "C": "Grouped vesicles on the right hemithorax", "D": "Pericardial friction rub", "E": "Absent left radial pulse"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A previously healthy 18-year-old woman comes to the emergency department because of diarrhea and abdominal cramps since the previous evening. She has had around 3–4 episodes of watery stools. She feels nauseous and has vomited twice. She recollects eating out 2 days ago. She has been on a vegan diet for 6 months. She takes no medications and has not traveled anywhere recently. Her temperature is 36.8°(98.2°F), pulse is 73/min, and blood pressure is 110/70 mm Hg. Examination shows dry mucous membranes. Abdominal examination is unremarkable. Which of the following is the most likely causal organism?", "answer": "Norovirus", "options": {"A": "Shigella dysenteriae", "B": "Rotavirus", "C": "Norovirus", "D": "Vibrio vulnificus", "E": "Bacillus cereus"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 6-year-old boy is brought to the physician for a well-child examination. He has no history of major medical illness. His mother says, “Sometimes when my son forgets to flush, his urine leaves dark stains in the toilet.” She is unconcerned because her son already had dark-colored urine as a baby and he has never had any health issues. His vital signs are within normal limits. Physical examination shows no abnormalities. The patient’s condition is most likely associated with impaired formation of which of the following?", "answer": "Maleylacetoacetate", "options": {"A": "Cystathionine", "B": "Methylmalonate", "C": "Niacin", "D": "Tyrosine", "E": "Maleylacetoacetate"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 72-year-old man presents with a recent episode of slurred speech and numbness in his left arm and left leg 2 hours ago that resolved completely within 45 minutes. He says he was having breakfast when he noticed that he had difficulty talking and the left side of his body was numb. The patient denies any past similar symptoms. Past medical history is significant for type 2 diabetes mellitus, hypertension, and ischemic heart disease. He had a coronary artery bypass graft 12 years ago and a percutaneous intervention 3 years ago. Current medications are aspirin, metformin, nitrates, and rosuvastatin. His vital signs include: blood pressure 143/97 mm Hg, pulse 80/min, oxygen saturation 98% on room air. On physical examination, the patient is alert and oriented. Higher mental functions are intact. Muscle strength is 5 out of 5l in both upper and lower limbs bilaterally. The sensation is intact. Cerebellar signs are absent and his gait is normal. Which of the following is the next best step in the management of this patient?", "answer": "Admit the patient for observation and workup", "options": {"A": "Add clopidogrel and discharge the patient", "B": "Admit the patient for observation and workup", "C": "Discharge now and ask him to visit again when symptoms reoccur", "D": "Refer for a psychiatrist review", "E": "Start antiepileptic drugs"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 29-year-old man is brought to the emergency department after being found unresponsive at home. The patient's roommate says that the patient had previously been feeling well. The patient and his roommate had a celebration the night before, where they drank homemade liquor. His temperature is 37°C (98.6°F), pulse is 126/min, respirations are 30/min and shallow, and blood pressure is 84/44 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 96%. He is unresponsive to painful stimuli. The pupils are 3 mm, equal, round, and reactive to light. The lungs are clear to auscultation. Cardiac examination shows a grade 2/6 systolic murmur along the left parasternal border. Laboratory studies show:\nSerum\nNa+ 146 mmol/L\nK+ 7.7 mmol/L\nCl- 111 mmol/L\nUrea nitrogen 5.8 mmol/L\nGlucose 83 mg/dL\nLactate 11.2 mmol/L\nSerum osmolality 379 mosm/kg\nArterial blood gas analysis shows:\npH 6.69\npCO2 53 mm Hg\npO2 84 mm Hg\nHCO3- 4.3 mmol/L\nThe patient is intubated and fluid resuscitation is begun. Which of the following is the most appropriate pharmacotherapy?\"", "answer": "Fomepizole", "options": {"A": "Ethanol", "B": "N-acetylcysteine", "C": "Fomepizole", "D": "Naloxone", "E": "Flumazenil"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 22-year-old woman presents with an episodic history of swelling of the face, hands, and neck and a single episode of difficulty swallowing. She also has a history of frequent, severe abdominal pain. At the time of her visit, her blood pressure is 126/84 mm Hg, heart rate is 82/min, and respiratory rate is 15/min. Physical examination is unremarkable except for a swollen right hand as shown in the image below. Imaging studies are normal and do not reveal any cause of her pain. Her C1 inhibitor level is less than 6% of the reference value. Which of the following is the most likely diagnosis for this patient?", "answer": "Hereditary angioedema", "options": {"A": "DiGeorge syndrome", "B": "Wiskott-Aldrich syndrome", "C": "Hereditary angioedema", "D": "Paroxysmal nocturnal hemoglobinuria", "E": "Chediak-Higashi syndrome"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 60-year-old man calls his hospital and asks to speak to his physician about laboratory test reports ordered because of a 3-month history of abdominal fullness and generalized fatigue. The referral note shows that he was constipated for the previous week. His abdominal examination had shown distention, and a 7-cm, hard, irregular, nontender mass was palpable on rectal examination. His colonoscopy report reveals a low anterior circumferential rectal lesion. An MRI of the pelvis shows a rectal mass with involvement of the prostate and seminal vesicles. A brief review of the results shows that an endoscopic biopsy confirms the clinical diagnosis of advanced rectal adenocarcinoma. His serum carcinoembryonic antigen concentration is 21.0 ng/mL (N < 2.5). The physician is tasked with delivering the diagnosis to the patient. Which of the following is the most appropriate statement by the physician at this time?", "answer": "\"\"\"I would like to meet later today at 4:00 PM so that we have enough time to discuss the lab results. If you'd like a friend or family member to accompany you, feel free to bring them along.\"\"\"", "options": {"A": "\"\"\"Your lab reports show that you have a locally advanced rectal adenocarcinoma\"\"\"", "B": "\"\"\"Would you like to know all the details of your diagnosis, or would you prefer I just explain to you what our options are?\"\"\"", "C": "\"\"\"I would like to meet later today at 4:00 PM so that we have enough time to discuss the lab results. If you'd like a friend or family member to accompany you, feel free to bring them along.\"\"\"", "D": "\"\"\"I may need to refer you to a cancer specialist because of your diagnosis. You may need chemotherapy or radiotherapy, which we are not equipped for.”\"", "E": "\"\"\"You must be be curious as to why all these tests were ordered, and you may even be anxious about the results.\"\"\""}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 50-year-old man has a kidney transplantation for end-stage renal disease in the setting of long-standing polycystic kidney disease. His postoperative course is uncomplicated. He had smoked one pack of cigarettes daily for 20 years but quit 5 years ago. He does not drink alcohol or use illicit drugs. Current medications include basiliximab, mycophenolate mofetil, and prednisone. His vital signs are within normal limits. On physical examination, the surgical incisions appear clean and intact. Prior to discharge, administration of which of the following is most appropriate in this patient?", "answer": "Trimethoprim-sulfamethoxazole", "options": {"A": "Azithromycin", "B": "Trimethoprim-sulfamethoxazole", "C": "Meningococcal vaccine", "D": "Acyclovir", "E": "Varicella vaccine"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 28-year-old woman, gravida 1, para 0, at 32 weeks' gestation comes to the physician for a prenatal visit. She has had no prenatal care. She emigrated from China 5 years ago and cannot recall all of her vaccinations. She appears well. Physical examination shows a uterus consistent in size with a 32-week gestation. Serum studies show:\nAnti-hepatitis A IgM antibody negative\nAnti-hepatitis A IgG antibody positive\nHepatitis B surface antigen negative\nAnti-hepatitis B surface antibody positive\nHepatitis B core antigen negative\nAnti-hepatitis B core antibody negative\nWhich of the following is the most appropriate next step in management?\"", "answer": "Plan normal vaginal delivery at term", "options": {"A": "Plan normal vaginal delivery at term", "B": "Determine hepatitis B e antigen serum level", "C": "Administer hepatitis B vaccine to mother", "D": "Counsel on necessity to avoid breastfeeding", "E": "Perform liver biopsy of mother"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 58-year-old woman presents to her family physician for an annual checkup. During the visit, the patient asks her physician for help quitting smoking cigarettes. She has unsuccessfully tried quitting several times previously and has also failed prior attempts with meditation and exercise. The physician prescribes a partial agonist of the nicotinic receptor to aid the patient in cessation. Which of the following is a potential side effect of this medication?", "answer": "Suicidal ideation", "options": {"A": "Impaired kidney function", "B": "Seizure", "C": "Sexual dysfunction", "D": "Suicidal ideation", "E": "Tachycardia"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 57-year-old man with chronic obstructive pulmonary disease comes to the emergency department because of leg swelling for 2 weeks. He has smoked 2 packs of cigarettes daily for the past twenty years. His vital signs are within normal limits. Physical examination shows jugular venous distention, hepatomegaly, and pitting edema of both lower extremities. Cardiac examination shows a regular heart rate and normal heart sounds. Auscultation of the lungs shows scattered wheezing without crackles. Left ventricular ejection fraction is 60%. Which of the following is the most likely underlying cause of this patient's condition?", "answer": "Chronic hypoxic vasoconstriction", "options": {"A": "Excessive systemic collagen deposition", "B": "Left-sided systolic heart failure", "C": "Ventricular septal defect", "D": "Chronic occlusion of the pulmonary vessels", "E": "Chronic hypoxic vasoconstriction"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A young Mediterranean teen brings her 4-year-old little brother to the Emergency Room because of a high temperature. Their parents are on their way to the hospital, but, in the meantime, she provides some of the history. She explains that he has been running a fever and limping for the past week. This morning, she had trouble awakening him, and she noticed some swelling and redness around his right ankle. In terms of his past medical history, she knows he has something wrong with his blood. He had to receive extra vaccinations as an infant, and he takes an antibiotic everyday. On exam in the ED, his temperature is 102.4 deg F (39.1 deg C), blood pressure is 90/60 mmHg, pulse is 123/min, and respirations are 22/min. He is lethargic, and his exam is noteworthy for erythema and edema in an area surrounding his distal shin. What is the most likely diagnosis?", "answer": "Osteomyelitis", "options": {"A": "Dactylitis", "B": "Avascular necrosis", "C": "Acute vaso-occlusive episode", "D": "Osteomyelitis", "E": "Thrombophlebitis"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 47-year-old man comes to the emergency department complaining of weight gain and abdominal discomfort. He states that over the past month he has gained 10 lbs. This week he began experiencing mild, diffuse abdominal discomfort. He denies nausea, vomiting, constipation, or diarrhea. The patient has not seen a physician in years and takes no medications. He is a truck driver. He states that he drinks a 6-pack of beer per night. On physical examination, there is jaundice, hepatomegaly, and a positive fluid wave. An abdominal ultrasound reveals cirrhosis, portal vein dilation, and moderate ascites. He undergoes a paracentesis that relieves his symptoms. Fluid analysis is shown below:\n\nSerum:\nAlbumin: 4.0 g/dL\n\nAscitic fluid:\nColor: Yellow\nLeukocyte count: 100/mm^3 with 50% neutrophils\nProtein: 2.3 g/dL\nAlbumin: 1.9 g/dL\n\nA culture is pending. He is discharged and instructed to follow-up with a gastroenterologist for an upper endoscopy. Upper endoscopy reveals multiple, small non-bleeding esophageal varices. Which of the following is the next best step in management of the patient’s condition?", "answer": "Propranolol", "options": {"A": "Atenolol", "B": "Ceftriaxone", "C": "Octreotide", "D": "Propranolol", "E": "Transjugular intrahepatic portosystemic shunt"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "An 8-month-old boy is brought to the office by his mother for recurrent infections. Over the past 2 months, the boy had multiple visits to the urgent care clinic for respiratory, ear, and skin infections. His mother is concerned about the health of her child. Currently, the child had a runny nose for the last 2 days. There is no fever but the mother adds that the boy is not eating very well. His mother denies any history of infection during her pregnancy and was tested negative for HIV. The patient’s heart rate is 90/min, respiratory rate is 14/min, and temperature is 36.7°C (98.0°F). On physical exam, there are decreased lung sounds in the left lower lobe. A chest X-ray reveals an absent thymic shadow and fails to show any lung pathology. There is no history of similar symptoms in the families of either parent. What is the most likely cause of this patient’s condition?\n ", "answer": "Adenosine deaminase deficiency", "options": {"A": "Adenosine deaminase deficiency", "B": "Hypoxanthine-guanine phosphoribosyl transferase (HGPRT) deficiency", "C": "HIV infection", "D": "Purine nucleoside phosphorylase deficiency", "E": "Adenosine kinase deficiency"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 4-year-old girl is brought to the physician because of a nonpruritic, painless rash on her face for 5 days. She was born at term and has been healthy since. Her 62-year-old maternal grandmother has bullous pemphigoid. Her development is adequate for her age and immunizations are up-to-date. She appears healthy and well-nourished. Her temperature is 37°C (98.6°F) and pulse is 90/min. Examination shows a nontender rash on the right side of the patient's face. An image of the patient's lower face is shown. The remainder of the examination shows no abnormalities. Which of the following is the most appropriate next step in management?", "answer": "Topical mupirocin therapy", "options": {"A": "Potassium hydroxide preparation", "B": "Oral acyclovir therapy", "C": "Oral cephalexin therapy", "D": "Skin biopsy", "E": "Topical mupirocin therapy"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 56-year-old man comes to the physician for a routine health maintenance examination. He has had mild pain in his left groin for 2 weeks. He was admitted to the hospital 1 month ago for myocardial infarction. Cardiac catheterization and angiography showed occlusion of the left anterior descending artery and he underwent placement of 2 stents. He has hypertension and hypercholesterolemia. There is no family history of serious illness. He has smoked 2 packs of cigarettes daily for 30 years. Current medications include aspirin, clopidogrel, rosuvastatin, and enalapril. His temperature is 36.7°C (98°F), pulse is 88/min, and blood pressure is 130/84 mm Hg. Examination shows a 3-cm (1.2-in), tender, pulsatile mass in the left thigh, below the inguinal ligament. There is mild erythema of the overlying skin. A loud murmur is heard on auscultation of the mass. Cardiopulmonary examination shows no abnormalities. There is no edema in the lower limbs. Femoral and pedal pulses are palpable bilaterally. Neurologic examination shows no focal findings. Which of the following is the most likely diagnosis?", "answer": "Femoral artery pseudoaneurysm", "options": {"A": "Femoral artery dissection", "B": "Femoral artery pseudoaneurysm", "C": "Femoral arteriovenous fistula", "D": "Femoral artery thrombosis", "E": "Femoral abscess"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 1-year-old girl is brought to the physician because of fever and crying while passing urine for 2 days. She was born at term and has been healthy since. Three months ago, she was treated for a urinary tract infection with oral cefixime. Her temperature is 39°C (102.2°F), pulse is 144/min, and blood pressure is 85/40 mm Hg. Physical examination shows no abnormalities. Her leukocyte count is 14,000/mm3. Urine dipstick shows leukocyte esterase and nitrites; urinalysis shows WBCs and gram-negative rods. Urine culture results are pending. Renal ultrasonography shows hydronephrosis of the left kidney. Empirical antimicrobial therapy is initiated, following which the patient's symptoms improve. Which of the following is the most appropriate next step in diagnosis?", "answer": "Voiding cystourethrography", "options": {"A": "Cystoscopy", "B": "Intravenous pyelography", "C": "Dynamic renal scintigraphy", "D": "Urodynamic testing", "E": "Voiding cystourethrography"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 69-year-old woman presents to her primary care physician complaining of a new-onset, left-sided, throbbing headache that has lasted for several days. She reports that the pain is worsened by eating. Which of the following is a complication of this condition if not treated promptly?", "answer": "Monocular blindness", "options": {"A": "Skin nodules", "B": "Intestinal ischemia", "C": "Monocular blindness", "D": "Myocardial infarction", "E": "Ischemic stroke"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 32-year old woman presents to the office complaining of progressively worsening shortness of breath for 2 months. She was seen multiple times in the past for complications of systemic lupus erythematosus that include anemia, pericarditis, and chronic interstitial lung disease. As she does not have medical insurance, she does not regularly follow up with her physician and also is not compliant with her medications. She does not drink alcohol, smoke cigarettes, or take illicit drugs. Her family history is positive for colon cancer in her father. Her temperature is 36.5°C (97.8°F), the blood pressure is 106/70 mm Hg, the pulse is 84/min, and the respirations are 16/min. Severe clubbing of her fingernails is noted. Which of the following best describes the pathogenesis of this patient's nail findings?", "answer": "Entrapment of megakaryocytes in the nail bed", "options": {"A": "Septic emboli", "B": "Atherosclerotic emboli", "C": "Entrapment of megakaryocytes in the nail bed", "D": "Nutritional deficiency, causing nails to be brittle and convex in shape", "E": "Chronic hypoxemia"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "An otherwise healthy 27-year-old woman presents to the emergency department because of worsening headaches and nosebleeds. Her blood pressure is 185/115 mm Hg, pulse is 88/min and temperature is 36.9°C (98.4°F). She denies the use of nicotine, alcohol, or illicit drugs. Family history is irrelevant. Physical examination is only positive for abdominal bruits. She is given a calcium-channel blocker and a thiazide diuretic, but her blood pressure did not respond adequately. Aldosterone-to-renin ratio is < 20. Which of the following is the most likely cause of this patient’s condition?", "answer": "Renal artery stenosis", "options": {"A": "Renal artery stenosis", "B": "Essential hypertension", "C": "Coarctation of the aorta", "D": "Primary aldosteronism", "E": "Cushing syndrome"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 50-year-old farmer from Jamaica presents to his physician with a wart-like lesion on his left foot. He is a plantain farmer and often farms barefoot because of the pleasant climate. Physical examination reveals warty, cutaneous nodules that resemble the florets of cauliflower. On a KOH preparation, irregular, dark brown, yeast-like bodies with septae are noted. Culture on Sabouraud agar reveals sclerotic bodies. Which of the following is the most likely diagnosis?", "answer": "Chromoblastomycosis", "options": {"A": "Mycetoma", "B": "Sporotrichosis", "C": "Rhinosporidiosis", "D": "Entomophthoromycoses", "E": "Chromoblastomycosis"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 52-year-old man comes to the physician because of a 3.6-kg (8-lb) weight loss over the past 3 months and increasing fatigue. He was diagnosed with hepatitis C 6 years ago. His father died of colon cancer. He has smoked one pack of cigarettes daily for 35 years and drinks one beer daily. He used cocaine and heroin in the past but stopped 12 years ago. He is 176 cm (5 ft 8 in) tall and weighs 71 kg (156 lb); BMI is 22.9 kg/m2. His temperature is 37.0°C (98.6°F), pulse is 79/min, and blood pressure is 115/75 mm Hg. He appears weak and lethargic. Examination shows scleral icterus and scars on both cubital fossae. There is reddening of the palms bilaterally. There are several telangiectasias over the chest and back. The abdomen is soft and nontender. The liver is firm and of nodular consistency. Laboratory studies show:\nHemoglobin 11.6 g/dL\nMean corpuscular volume 88 μm3\nLeukocyte count 9,600/mm3\nPlatelet count 223,000/mm3\nUltrasonography of the liver shows a solitary lesion. Which of the following findings is most likely in this patient?\"", "answer": "Elevated α-fetoprotein", "options": {"A": "Positive blood cultures", "B": "Elevated α-fetoprotein", "C": "Elevated carcinoembryonic antigen", "D": "Exophytic tumor on colonoscopy", "E": "Spiculated lesion on chest CT"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 63-year-old man comes to the physician for the evaluation of difficulty walking for the last 6 months. He reports weakness in his lower legs that improves with exercise and throughout the day. Three months ago, he started adding flax seeds to his breakfast because he is frequently constipated. He has hypertension and type 2 diabetes mellitus. He has smoked 2 packs of cigarettes daily for the last 45 years. His current medications include enalapril and metformin. Vital signs are within normal limits. Examination shows dry mucous membranes. Muscle strength in the lower extremities is decreased. Sensation to pinprick and light touch is normal. Deep tendon reflexes are 1+ bilaterally. Active muscle contraction or repeated muscle tapping increases reflex activity. Which of the following is most likely to confirm the diagnosis?", "answer": "Autoantibodies against voltage-gated calcium channels", "options": {"A": "Demyelinating plaques on a brain MRI", "B": "Autoantibodies against voltage-gated calcium channels", "C": "Decremental response following repetitive nerve stimulation", "D": "Fasciculations and positive sharp waves on EMG", "E": "Albuminocytologic dissociation in cerebrospinal fluid"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 5-year-old boy is brought to the emergency department by his mother because of abdominal pain. His mother says that he has not had any fever, vomiting, diarrhea, or dysuria. His last bowel movement was 3 days ago and appeared normal. The boy is restless and clutches his abdomen. His temperature is 37.2°C (99°F), blood pressure is 108/76 mm Hg, pulse is 110/min, respirations are 20/min. The abdomen appears mildly distended. On auscultation, he has hyperactive bowel sounds. The remainder of the examination shows no abnormalities. An ultrasound of the abdomen shows no abnormalities. Which of the following is the most appropriate next step in management?", "answer": "Administer polyethyelene glycol", "options": {"A": "Administer polyethyelene glycol", "B": "Reassurance and observation", "C": "Administer intravenous fluids", "D": "Perform a barium enema", "E": "Start empirical antibiotic therapy"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 30-year-old woman presents to the emergency department with chest pain. She states that she was making coffee this morning when she suddenly developed sharp, 8/10, mid-sternal chest pain. The pain does not radiate and is constant. She is worried because she has a marathon next week that she has been training for. Her medical history is significant for seasonal allergies. She takes no medications except a multivitamin. Her mother has asthma. She works as a lawyer. She denies sick contacts or recent travel. She has a glass of wine with dinner but denies tobacco or recreational drug use. The patient’s initial temperature is 98°F (36.7°C), blood pressure is 122/78 mmHg, pulse is 89/min, and respirations are 14/min with an oxygen saturation of 98% on room air. A physical examination is within normal limits. Labs are pending. Which of the following is the best initial step in management?", "answer": "Electrocardiogram", "options": {"A": "Aspirin, oxygen, nitroglycerin, and morphine", "B": "Computerized tomography scan", "C": "Electrocardiogram", "D": "Heparin", "E": "Reassurance"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 34-year-old woman, gravida 2, para 1, at 34 weeks' gestation comes to the physician because of a 10-day history of generalized pruritus and a 2-day history of jaundice, dark urine, and pale stools. She had developed pruritus at the end of her previous pregnancy, which disappeared after delivery. She has had standard prenatal care. Medications include folic acid and a multivitamin. Her blood pressure is 108/60 mm Hg. Examination shows scleral icterus, jaundice, and scratch marks on her upper and lower limbs. Pelvic examination shows a uterus consistent in size with a 30-week gestation.\nHemoglobin 11.5 g/dl\nPlatelet 350,000/mm3\nProthrombin time 11 seconds (INR=1)\nSerum\nTotal bilirubin 5 mg/dl\nDirect bilirubin 4.2 mg/dl\nBile acid\n25 μmol/l (N= 0.3 to 10 μmol/l)\nAspartate aminotransferase 55 U/L\nAlanine aminotransferase 45 U/L\nThere are no abnormalities on abdominopelvic ultrasonography. Which of the following is the most appropriate next step in management?\"", "answer": "Ursodeoxycholic acid", "options": {"A": "24-hour urine protein", "B": "Emergency endoscopic retrograde cholangiopancreatography and sphincterotomy", "C": "Immediate induction of labor", "D": "Laparoscopic cholecystectomy within 48 to 72 hours", "E": "Ursodeoxycholic acid"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A mother brings her 17-year-old daughter to your office because of a recent onset dull unilateral pelvic pain that started last week. In addition, the daughter also complains of constipation for which she increased her fiber intake, but the dietary changes are not helping her. She began menstruating at the age of 13, and her menstrual cycles are regular (about 28 days). On physical examination, the patient has a large, non-tender, mobile adnexal mass in the left lower quadrant. The pelvic examination is normal except for the presence of the adnexal mass. The patient is advised to have an outpatient ultrasound, and then return to the clinic next week. After 2 weeks, you learned that the patient visited the emergency department for a sudden onset of abdominal pain that required observation after an abdominal ultrasound was performed. The ultrasound showed a large simple cystic mass with increased internal echoes, having a diameter of 10 cm and hyperechogenic vascular walls on the left ovary with a small intraperitoneal collection in the pouch of Douglas. What was the most likely diagnosis of this patient?", "answer": "Corpus luteum cyst", "options": {"A": "Follicular cyst", "B": "Endometrioma", "C": "Tubo-ovarian abscess", "D": "Corpus luteum cyst", "E": "Dermoid cyst"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 22-year-old woman comes to the clinic complaining of right anterior knee pain. She reports that the pain has been present for 3 months and has gradually worsened. She says the pain is exacerbated when climbing or descending the stairs. She also states the pain is sometimes worse with prolonged periods of sitting. She has tried over-the-counter aspirin and ibuprofen without relief. She is a soccer player and is worried that the pain is starting to affect her ability to play. She reports multiple minor lower extremity injuries due to soccer but denies significant trauma such as known fractures or torn ligaments. Her past medical history is unremarkable. She had a myringotomy in her left ear as a child. On examination, there is pain and crepitus on extension of the right knee with anterior patellar compression. Which of the following is the most appropriate management of the patient’s symptoms?", "answer": "Quadriceps exercises", "options": {"A": "Aspiration", "B": "Lidocaine injection", "C": "Orthopedic surgery", "D": "Ossicle resection", "E": "Quadriceps exercises"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 25-year-old woman is brought to the emergency department by her husband for abdominal pain. The husband answers all questions posed to the patient by the physician. Throughout the interview, the patient makes very little eye contact with the physician. Her husband asks the physician to prescribe “something for her abdominal pain” so that they can return home. Examination of the patient shows mild bruising in the left infraorbital area and a right periorbital hematoma. When asked about her injuries, she quietly states that she fell while walking down the stairwell of her apartment complex. The husband reluctantly leaves the examination room when asked to by the physician. While alone with the physician, the patient admits that her husband is responsible for her injuries. Which of the following immediate responses by the physician is most appropriate?", "answer": "\"\"\"Do you feel safe leaving the emergency department?\"\"\"", "options": {"A": "\"\"\"May I add some information about local domestic violence agencies to your discharge records?\"\"\"", "B": "\"\"\"Do you feel safe leaving the emergency department?\"\"\"", "C": "\"\"\"Don't you think you should report this incident to the police?\"\"\"", "D": "\"\"\"How often has your husband physically hurt you in the past?\"\"\"", "E": "“May I ask your husband to join us so we can talk about this matter together?”"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 15-year-old girl comes to the physician because of a 2-month history of progressive fatigue and weakness. She also reports recurrent headaches for 2 years, which have increased in severity and frequency. Her blood pressure is 185/95 mm Hg. Serum studies show a morning renin activity of 130 ng/mL per hour (N=1–4), a morning aldosterone concentration of 60 ng/dL (N=5-30), and a potassium concentration of 2.9 mEq/L. Further evaluation is most likely to show which of the following?", "answer": "Pleomorphic modified smooth muscle cells in the renal cortex", "options": {"A": "ACTH-producing growth in the pituitary gland", "B": "Increased urinary excretion of metanephrines", "C": "Increased 17-hydroxyprogesterone levels", "D": "Pleomorphic modified smooth muscle cells in the renal cortex", "E": "Involution of zona glomerulosa of the adrenal gland"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 15-year-old boy is brought to the emergency department by his mother because of severe left testicular pain for 1 hour. For the past week, he has also had mild testicular pain and pain on urination. He has not had nausea or vomiting. He is otherwise healthy. His temperature is 39.1°C (102.3°F), pulse is 114/min, and blood pressure is 120/76 mm Hg. Examination shows a high-riding, swollen, erythematous tender left testis; lifting the left testis relieves his pain. His hemoglobin concentration is 15.6 g/dL, leukocyte count is 14,600/mm3, and platelet count is 290,000/mm3. Testicular ultrasound shows increased blood flow to the left testicle when compared to the right and an enlarged left epididymis with decreased echogenicity. Further evaluation of this patient is most likely to show which of the following findings?", "answer": "Positive nucleic acid amplification testing", "options": {"A": "Reducible scrotal mass", "B": "Gram-negative rods in urethral swab", "C": "A hard testicular mass", "D": "Positive nucleic acid amplification testing", "E": "Absent cremasteric reflex"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 27-year-old female presents to the emergency department with complaints of acute-onset fatigue, blurred vision, and rash earlier today. Her husband rushed her to emergency department when he noted that she was exhibiting changes in her mental status and had trouble speaking. Her vital signs are as follows: T 38.4, HR 87, BP 110/85, RR 14, and SpO2 96%. Physical examination reveals petechiae, pallor, and left upper extremity weakness. Work-up reveals Hgb 8.5 g/dL, platelets 22,000 cells/uL, normal PT/INR and PTT, absent fibrin split products, elevated fibrinogen, a negative Coombs test, 3.7 mg/dL creatinine, 3.8 mg/dL indirect bilirubin, and LDH 1000 IU/L. Which of the following would be expected on a peripheral blood smear from this patient?", "answer": "Schistocytes", "options": {"A": "Ovalocytes", "B": "Spherocytes", "C": "Atypical lymphocytes", "D": "Schistocytes", "E": "Rouleaux formation"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 67-year-old African American male presents to his primary care physician for routine follow-up. He has a history of poorly controlled hypertension, despite being on lisinopril, hydrochlorothiazide, amlodipine and metoprolol, which he takes regularly. His blood pressure during the visit is 170/80. He does not have kidney disease. His primary care physician decides to start him on methyldopa. What is the mechanism of action of methyldopa?", "answer": "Centrally acting alpha2 adrenergic receptor agonist", "options": {"A": "Direct vascular smooth muscle relaxation", "B": "Dopamine receptor agonist", "C": "Inhibition of angiotensin converting enzyme", "D": "Centrally acting alpha2 adrenergic receptor agonist", "E": "Inhibition of alpha1 adrenergic receptors"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 2800-g (6-lb 3-oz), 3-day-old newborn is in the intensive care unit for fever, vomiting, tremors, cyanotic episodes, and seizures. She was born at 36 weeks to a 25-year-old primigravid woman. Spontaneous vaginal delivery was complicated by maternal fever and chorioamnionitis. Apgar scores were 6 at 1 minute and 7 at 5 minutes, respectively. Shortly after delivery, the child had seizures and high-grade fever with poor feeding and hypotonia. She was intubated for respiratory distress. Her temperature is 39°C (102.3°F), pulse is 180/min, and respirations are 60/min. Physical exam shows grunting breath sounds, an enlarged liver palpable 3 cm below the right costal margin, and lethargy. A CT scan of the chest, abdomen, and pelvis shows multiple pulmonary and hepatic granulomas. Which of the following would most likely have prevented this complication?", "answer": "Avoiding unpasteurized milk products", "options": {"A": "Avoiding unpasteurized milk products", "B": "Measles, mumps, rubella vaccination before pregnancy", "C": "Prophylactic penicillin", "D": "Prophylactic acyclovir", "E": "Delivery via cesarean section"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 45-year-old woman presents to her primary care practitioner requesting a routine checkup for a job application. Her family history is negative for malignancies and inheritable diseases. She has been married for 15 years and has 2 healthy children. Her past medical history is negative for surgical procedures and cardiovascular disease; however, she used to work as a radiology technician. Her only complaints at the moment are neck pain and hoarseness. Physical examination is unremarkable except for a painless nodule in the right lobe of the thyroid gland with no inflammatory signs. In a follow-up appointment, the patient brings the results of her thyroid function tests, which are normal. She also brings the results of a fine-needle aspiration biopsy that report the pathology of the nodule as follicular neoplasia. After some discussion, the patient opts for surgical treatment. With a surgical pathology report that describes vascular invasion, which of the following additional features would you expect to find for this thyroid nodule?", "answer": "Capsular invasion", "options": {"A": "Capsular invasion", "B": "Cystic nature", "C": "Psammoma bodies", "D": "Eosinophil and macrophage invasion", "E": "Pleomorphic cells without follicle development"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 65-year-old man comes to the physician because of progressive shortness of breath and a worsening cough for the past month. He also reports occasional bloody sputum. He has lost about 7 kg (15.4 lb) of weight over the past 4 months despite having no change in appetite. He has smoked 2 packs of cigarettes daily for 15 years but stopped smoking at the age of 55. Physical examination shows reduced breath sounds throughout both lungs. An x-ray of the chest is shown. Which of the following is the most likely cause of the patient's symptoms?", "answer": "Pulmonary metastases", "options": {"A": "Squamous cell lung carcinoma", "B": "Small cell lung cancer", "C": "Lung adenocarcinoma", "D": "Pulmonary metastases", "E": "Pleural mesothelioma"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 67-year-old man comes to the physician due to exertional dyspnea and lower extremity swelling for the last 4 weeks. The patient has been a smoker for the last 45 years and has been diagnosed with COPD. He has no history of diabetes mellitus or ischemic heart disease. He is non-compliant with his medications for COPD. The patient is a retired social worker and spends most of his time at home. His temperature is 37.2°C (98.9°F), blood pressure is 135/115 mm Hg, pulse is 90/min, and respirations are 22/min. Oxygen saturation on room air is 92%. Physical examination reveals a barrel-shaped chest, distension of neck veins, and 3+ bilateral pitting edema of his lower extremities. The liver is palpated 6 cm below the costal margin and is tender to palpation. Application of pressure on the upper abdomen causes persistent distension of jugular veins. Lungs are clear to auscultation. Chest X-ray shows enlarged main pulmonary arteries. ECG shows right bundle branch block and right ventricular hypertrophy. Which of the following is the gold standard test for diagnosing this patient’s condition?", "answer": "Right heart catheterization", "options": {"A": "Pulmonary capillary wedge pressure", "B": "Right heart catheterization", "C": "Coronary angiography", "D": "Abdominal paracentesis", "E": "Ultrasound of liver"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 13-year-old African-American girl is brought to the physician for right shoulder pain that has worsened over the past month. She has had many episodes of joint and bone pain and recurrent painful swelling in her hands and feet. Physical examination shows tenderness of the right anterior humerus without swelling or skin changes. Active and passive range of motion of the right shoulder is decreased and there is pain with movement. The leukocyte count is 4600/mm3. An x-ray of the right shoulder shows subchondral lucency of the humeral head with sclerosis and joint space narrowing. Which of the following is the most likely underlying cause of this patient's shoulder pain?", "answer": "Infarction of the bone trabeculae", "options": {"A": "Infection of the joint space", "B": "Crystal deposition within the joint", "C": "Loss of bone mineral density", "D": "Infarction of the bone trabeculae", "E": "Infection of the bone"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 4-month-old male presents to the emergency department with severe cough, wheezing, and cyanosis. You suspect bronchiolitis of viral etiology and you administer an anti-viral medication. This drug is often used to treat which one of these other infections?", "answer": "Hepatitis C", "options": {"A": "HIV", "B": "Hepatitis B", "C": "Hepatitis C", "D": "Rhinovirus", "E": "HSV"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 43-year-old woman presents to the clinic complaining of “spotting.” She states that over the past 5 months she has had intermenstrual bleeding. Additionally, her menses last more than a week with the first 4 days consisting of heavy bleeding. She denies abdominal pain but reports feeling an increasing “pressure-like\" discomfort. She denies dysuria, dyspareunia, or dyschezia. Prior to 5 months ago, her menstrual periods were only 4 days long and consisted of moderate bleeding. Her periods normally occur every 28 days. She is frustrated because she feels like she needs to wear a pad all the time. The patient delivered 3 healthy children vaginally without complications, followed by a tubal ligation. Her last menstrual period was 1 week ago. She is sexually active with her husband and denies a history of sexually transmitted diseases. She has never had an abnormal pap smear. Her last pap smear and test for human papillomavirus was 4 years ago. The patient has hypothyroidism treated with levothyroxine. On physical examination, the thyroid is normal in size without masses or tenderness. Pelvic examination reveals a firm, mobile, enlarged, irregularly-shaped uterus without adnexal tenderness. Speculum exam is unremarkable. Which of the following is the most likely diagnosis?", "answer": "Leiomyoma", "options": {"A": "Adenomyosis", "B": "Cervical cancer", "C": "Endometriosis", "D": "Hypothyroidism", "E": "Leiomyoma"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 19-year-old woman comes to the physician because of a 1-week history of fatigue and yellow discoloration of her eyes. Four weeks ago, she had a sore throat and was diagnosed with a viral infection that self-resolved. She has no history of serious medical illness. Her only medication is an oral contraceptive. She appears tired. Her pulse is 94/min, and blood pressure is 125/75 mm Hg. Physical examination shows scleral icterus. The liver edge is palpable 2 cm below the right costal margin and the spleen tip is palpable 4 cm below the left costal margin. Skin examination shows no rashes. Her hemoglobin concentration is 9.5 g/dL, and the direct antiglobulin test is positive. Which of the following additional laboratory findings is most likely in this case?", "answer": "Decreased haptoglobin level", "options": {"A": "Increased serum C3 complement concentration", "B": "Increased direct bilirubin level", "C": "Decreased haptoglobin level", "D": "Decreased mean corpuscular volume", "E": "Increased bleeding time"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 67-year-old female is admitted to the hospital with enterococcus endocarditis and is treated with penicillin and gentamicin. During her admission, she develops worsening pulmonary edema secondary to valvular insufficiency and requires therapy with IV furosemide. This patient is most likely to experience which of the following adverse reactions to her current pharmacological treatment:", "answer": "Ringing in the ears and impaired hearing", "options": {"A": "Ringing in the ears and impaired hearing", "B": "Hyperkalemia leading to possible cardiac arrhythmia", "C": "Anemia and chronic fatigue", "D": "Diffuse flushing and redness over body surface", "E": "Pseudomembranous colitis and diarrhea"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 75-year-old male is brought to the emergency room by his daughter due to slurred speech and a drooping eyelid on the right side. This morning, he had difficulty eating his breakfast and immediately called his daughter for help. She says that his voice also seems different. His temperature is 99°F (37.2°C), blood pressure is 120/78 mmHg, pulse is 90/min, respirations are 21/min, and pulse oximetry is 98% on room air. On physical exam, he is oriented to time and place. There is right-sided nystagmus and he has difficulty with point-to-point movement. Where is the lesion responsible for his symptoms most likely located?", "answer": "Posterior inferior cerebellar artery", "options": {"A": "Anterior spinal artery", "B": "Posterior inferior cerebellar artery", "C": "Anterior cerebral artery", "D": "Anterior inferior cerebellar artery", "E": "Basilar artery"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "You are conducting an experiment on a cell line in your laboratory. You introduce a molecule into the tissue culture dish containing the cell line that binds to a transmembrane protein. As a result, the affected cell initiates a process characterized by karyorrhexis, membrane blebbing, and pyknosis. What was the molecule that you introduced into the culture?", "answer": "FAS-ligand", "options": {"A": "Perforin", "B": "Granzyme B", "C": "FAS-ligand", "D": "IL-2", "E": "BCL-2"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 45-year-old woman comes to the physician because of a 6-month history of progressive irritability, palpitations, heat intolerance, frequent bowel movements, and a 6.8-kg (15-lb) weight loss. She also has a smooth, uniformly enlarged mass at the front of her neck and protuberant eyes with lid retraction. Laboratory investigations show undetectable levels of thyroid stimulating hormone, elevated levels of free T3 and T4, and a raised titer of TSH receptor autoantibodies (TRAbs). Therapy is initiated with radioactive iodine-131. This patient is at greatest risk for which of the following complications?", "answer": "Worsening exophthalomos", "options": {"A": "Radiation thyroiditis", "B": "Worsening exophthalomos", "C": "Agranulocytosis", "D": "Vocal cord paralysis", "E": "Thyroid carcinoma\n\""}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 56-year-old woman comes to the emergency department because of severe abdominal pain associated with nausea and vomiting for 12 hours. The pain extends from the epigastrium to the right upper quadrant and radiates to the right scapula. The patient has gastroesophageal reflux disease. She underwent total thyroidectomy for papillary thyroid carcinoma 3 years ago. She has smoked one pack of cigarettes daily for 35 years. Current medications include levothyroxine, omeprazole, and a multivitamin. The patient appears uncomfortable. Her temperature is 38.1°C (100.6°F), pulse is 93/min, and blood pressure is 140/85 mm Hg. Abdominal examination shows tenderness to deep palpation in the right upper quadrant. The patient's leukocyte count is 10,300/mm3. Abdominal ultrasonography shows thickening of the gallbladder wall, without dilatation of the intra- and extrahepatic bile ducts. Laparoscopic cholecystectomy is performed. Pathological examination shows acute cholecystitis. There is an ulcerated 1 x 1.5-cm mass in the fundus of the gallbladder with invasion of the gallbladder wall and lymphatic vessels. Which of the following is the most likely underlying condition?", "answer": "Cutaneous malignant melanoma", "options": {"A": "Adenocarcinoma of the sigmoid colon", "B": "Cutaneous malignant melanoma", "C": "Recurrence of papillary thyroid carcinoma", "D": "Multiple endocrine neoplasia", "E": "Squamous cell carcinoma of the esophagus\n\""}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "You are on your first day of a pathology rotation and the attending pathologist gives you a biopsy specimen to examine. She says it is from the antrum of the stomach of a 32-year-old man who has been complaining of abdominal pain for the past 6 months. The patient states the pain gets worse when eating. On endoscopy, there was a single ulcerated lesion with a 'punched out' appearance. What are the most likely histologic findings in this biopsy specimen?", "answer": "A urease-positive organism", "options": {"A": "Signet ring cells", "B": "An abundance of self reactive T cells", "C": "A urease-positive organism", "D": "Absence or evidence of destruction of parietal cells", "E": "The presence of a large amount of neutrophils with limited macrophages"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 40-year-old man is brought into the emergency department by his wife complaining of intense lower right abdominal pain. An abdominal CT scan was performed which noted a dilated appendix with a thickened wall and the accumulation of extraluminal fluid. A quick history is taken while the OR is prepped for surgery. Past medical history is noncontributory and the patient takes no medications. Social history reveals a sedentary lifestyle. The patient admits to regularly drinking several beers and several shots of vodka every night. He had to stop drinking 2 days ago due to the intense abdominal pain. The patient is brought into the OR and the inflamed and necrotic appendix is removed. He is admitted to the hospital for overnight monitoring. Later that night, the patient begins to hallucinate. Which type of hallucination is this patient likely to experience?", "answer": "Tactile hallucination", "options": {"A": "Proprioceptive hallucinations", "B": "Olfactory hallucination", "C": "Gustatory hallucination", "D": "Hypnagogic hallucination", "E": "Tactile hallucination"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 34-year-old woman presents with sudden onset flank pain for the past day. She describes the pain as intermittent and radiating to her groin. She denies any similar symptoms in the past. No significant past medical history. The patient currently does not take any medications. Family history is significant for her mother who died of a pancreatic tumor at the age of 53. Laboratory analysis reveals:\nSerum calcium 12 mg/dL\nSerum phosphorus 2.2 mg/dL\nSerum parathyroid hormone 105 pg/mL\nWhich of the following mutated gene products is most likely causing this patient’s symptoms?", "answer": "Menin", "options": {"A": "Receptor tyrosine kinase", "B": "Cytokine receptor", "C": "Antiapoptotic molecule", "D": "Threonine kinase", "E": "Menin"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "As a public health practitioner, you are charged with choosing which blood test to use for the screening of a new infectious disease. You want to ensure that as many cases of this disease as possible are picked up by this initial screening test. Which of the following is the highest priority characteristic of this new test?", "answer": "Highly sensitive test", "options": {"A": "Highly sensitive test", "B": "Highly specific test", "C": "Low false positive rate", "D": "High true positive rate", "E": "Low negative predictive value"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 25-year-old man is brought into the hospital by his family because they are concerned that he has post-traumatic stress disorder. The patient is a marine and was deployed to Afghanistan 2 years ago. He was able to successfully reintegrate with society upon his return; however, for the last 2 weeks, he has been having recurrent nightmares and avoiding news coverage on the war. He has become more and more detached from his family and friends and, on the few times he does interact with them, he has angry outbursts. The patient is afebrile, and his vital signs are within normal limits. Physical examination is unremarkable. Which of the following findings is most important in correctly diagnosing this patient’s condition?", "answer": "Duration of symptoms", "options": {"A": "Duration of symptoms", "B": "Flashbacks", "C": "State of hyperarousal", "D": "Avoidance of triggers", "E": "Negative Mood"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 4-year-old girl is brought to the pediatrician because of throat pain for 2 days. She had frequent episodes of oral thrush as a baby and has been treated for vaginal yeast infection twice in the past year. Physical examination shows white patches on the tongue and palate. Scraping off the patches reveals erythematous oral mucosa with pinpoint bleeding. Leukocyte count is within normal range. Exposure to nitroblue tetrazolium turns the patient's neutrophils dark blue. A deficiency in which of the following enzymes is the most likely cause of this patient's recurrent infections?", "answer": "Myeloperoxidase", "options": {"A": "Adenosine deaminase", "B": "Pyruvate kinase", "C": "Glucose-6-phosphate dehydrogenase", "D": "NADPH oxidase", "E": "Myeloperoxidase"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 55-year-old male with chronic dyspnea is intubated and started on mechanical ventilation for respiratory failure. Pressure-volume scalars on the ventilator show decreased change in volume for each unit change in pressure as compared to normal values. Of the following options, which is the most likely cause of his respiratory failure?", "answer": "Pulmonary fibrosis", "options": {"A": "Amyotrophic lateral sclerosis", "B": "Asthma", "C": "Centriacinar emphysema", "D": "Pulmonary fibrosis", "E": "Alpha-1-antitrypsin deficiency"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 6-year-old African-American boy presents with severe pain and swelling of both his hands and wrists. His symptoms onset 2 days ago and have not improved. He also has had diarrhea for the last 2 days and looks dehydrated. This patient has had two similar episodes of severe pain in the past. Physical examination reveals pallor, jaundice, dry mucous membranes, and sunken eyes. Which of the following mutations is most consistent with this patient’s clinical condition?", "answer": "Missense", "options": {"A": "Chromosomal deletion", "B": "Nonsense", "C": "Silent", "D": "Missense", "E": "Frame shift"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 45-year-old woman presents to her primary care physician with complaints of weight loss and anxiety. She says that over the past 6 months she has lost 10 pounds even though she has had an increased appetite. In addition, she describes 3 episodes where it felt like her heart was \"pounding out of her chest.\" Her temperature is 99.3°F (37.4°C), pulse is 106/min and regular, blood pressure is 141/80 mmHg, and respirations are 18/min. Physical exam is significant for mild bilateral proptosis and 3+ deep tendon reflexes bilaterally. Which of the following is the best initial therapy for the patient's condition?", "answer": "Propranolol", "options": {"A": "Adenosine", "B": "Methimazole", "C": "Potassium iodide", "D": "Propranolol", "E": "Thyroidectomy"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 58-year-old woman is brought to the emergency department by her husband because of increasing confusion and generalized fatigue over the past week. During this period, she has had muscle cramps, headaches, nausea, and vomiting. Six days ago, she underwent resection of a parasagittal meningioma. She tolerated the procedure well without complications and was discharged two days ago. She has hypercholesterolemia and hypertension. Current medications include oxycodone, acetaminophen, atorvastatin, and hydrochlorothiazide. She is oriented only to person and place. Her temperature is 37°C (98.6°F), pulse is 89/min, respiratory rate is 14/min, and blood pressure is 142/88 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 97%. The remainder of the examination shows no abnormalities. Serum studies show:\nSerum\nNa+ 126 mEq/L\nK+ 3.6 mEq/L\nCl- 107 mEq/L\nUrea nitrogen 16 mg/dL\nGlucose 87 mg/dL\nCreatinine 0.9 mg/dL\nOsmolality 255 mOsmol/kg H2O\nUrine\nOsmolality 523 mOsmol/kg H2O\nSodium 44 mEq/L\nWhich of the following is the most likely cause of this patient's symptoms?\"", "answer": "Syndrome of inappropriate antidiuretic hormone", "options": {"A": "Cerebral salt wasting syndrome", "B": "Hydrochlorothiazide", "C": "Syndrome of inappropriate antidiuretic hormone", "D": "Primary polydipsia", "E": "Mineralocorticoid deficiency"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 55-year-old man comes to the emergency department because of left arm pain after falling from a ladder. Physical examination shows tenderness along the proximal left humerus. An x-ray of the left arm and shoulder shows a nondisplaced proximal humerus fracture. Which of the following cytokines is most likely to be involved in normal bone healing in this patient?", "answer": "Macrophage colony-stimulating factor", "options": {"A": "Interleukin-4", "B": "Interleukin-2", "C": "Interferon-α", "D": "Granulocyte colony-stimulating factor", "E": "Macrophage colony-stimulating factor"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 62-year-old African American man is admitted to the emergency department with a 24-hour history of intense epigastric pain that radiates to the back with nausea and vomiting. His medical history is relevant for hypertension, heart failure (HF), chronic obstructive pulmonary disease (COPD), and radicular pain, all under control with amlodipine, furosemide, ipratropium, and gabapentin. He drinks occasionally at family gatherings and has never smoked cigarettes. His vital signs are recorded as follows: blood pressure of 130/80 mm Hg, a heart rate of 78/min, a respiratory rate of 18/min, and a body temperature of 36.6°C (97.9°F). Abdominal examination shows edema and bruising of periumbilical subcutaneous tissue and intense pain to touch but no signs of peritoneal irritation. Which of the following is the most likely responsible for this patient’s condition?", "answer": "Furosemide", "options": {"A": "Amlodipine", "B": "Furosemide", "C": "Ipratropium", "D": "Gabapentin", "E": "Alcohol consumption"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 62-year-old woman presents to the emergency department complaining of intense pain in her right knee that started 12 hours ago. Her past medical history is significant for hemochromatosis, managed with biweekly phlebotomy. Her vitals include: blood pressure of 130/70 mm Hg, pulse of 82/min, respiratory rate of 18/min, and temperature of 36.5°C (97.7°F). Physical examination reveals an erythematous, warm, and severely tender right knee with a restricted range of motion. An arthrocentesis is performed, and synovial fluid analysis is significant for a neutrophil count of 3,200 cells/μL, a negative Gram stain, and the following result under polarized light microscopy (see image). Which of the following additional findings would you also expect to observe in this patient?", "answer": "Chondrocalcinosis", "options": {"A": "Chondrocalcinosis", "B": "Lipohemarthrosis", "C": "Urate tophi", "D": "Heberden's nodes", "E": "Rheumatoid nodules"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 52-year-old man with a history of mild chronic obstructive pulmonary disease (COPD) has been using albuterol as needed to manage his COPD without any other maintenance medications. Recently, he has been experiencing a greater degree of shortness of breath, wheezing, and a productive cough. He denies any recent changes to his activities of daily living, exercise, or recent upper respiratory illnesses. The vital signs include: temperature 36.7°C (98.0°F), blood pressure 126/74 mm Hg, heart rate 74/min, and respiratory rate 14/min. His physical examination shows decreased breath sounds bilateral, and expiratory wheezes, a barrel-shaped chest, and a holosystolic murmur heard best at the 2nd intercostal space on the left. Pulmonary function tests demonstrate a forced expiratory volume-1 (FEV-1) which is 60% of the predicted value. What is the next best step for the management of his COPD?", "answer": "Add tiotropium to treatment regimen", "options": {"A": "Add budesonide to treatment regimen", "B": "Add rofilumast to treatment regimen", "C": "Add tiotropium to treatment regimen", "D": "Add tiotropium plus fluticasone to treatment regimen", "E": "Add carbocysteine to treatment regimen"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 24 year-old male presented to his physician with a homogenous, painless testicular swelling that he noticed for the past two weeks. After ultrasound and blood tests, he subsequently underwent a radical inguinal orchiectomy and pathology was consistent with seminoma. Which of the following would you expect to see in a tissue sample from the patient’s orchiectomy?", "answer": "Lobules of large cells with prominent nuclei and watery cytoplasm", "options": {"A": "Lobules of large cells with prominent nuclei and watery cytoplasm", "B": "Schiller-Duval bodies", "C": "Reinke crystals", "D": "Tubular papillary architecture with necrosis", "E": "Mature derivatives of endoderm, mesoderm, and ectoderm"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 31-year-old man comes to the physician because of diarrhea, bloating, nausea, and vomiting for the past week. He describes his stool as greasy, frothy, and soft; it is not red or darkened. The patient went on a hiking trip in Brazil 3 weeks ago. He has no history of serious illness and takes no medications. The patient appears dehydrated. His vital signs are normal. Examination shows dry mucous membranes and diffuse abdominal tenderness. Microscopy of the stool reveals egg-shaped cysts with prominent two-layered cell wall and multiple nuclei. Which of the following is the most appropriate treatment?", "answer": "Metronidazole therapy", "options": {"A": "Supportive treatment only", "B": "Vancomycin therapy", "C": "Trimethoprim-sulfamethoxazole therapy", "D": "Metronidazole therapy", "E": "Octreotide therapy"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 48-year-old man presents to the clinic feeling depressed after a string of failed business projects. His team noticed that he seems less engaged than he once used to be and this is reflecting in his work. He has no previous psychiatric history and symptoms of depressed mood have been ongoing for the past 6 months. A patient health questionnaire 9 (PHQ-9) was administered and the patient scored 10. The patient is started on venlafaxine. The alteration in the normal functioning of which of the following is the mechanism of action for this therapy?", "answer": "Serotonin, norepinephrine, and dopamine", "options": {"A": "Serotonin, norepinephrine, and dopamine", "B": "Norepinephrine and dopamine", "C": "Serotonin only", "D": "Serotonin receptor antagonism", "E": "Alpha-2 receptor antagonism"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A researcher is performing an experiment where she is using bacteria to clone copies of a mutated gene that she plans on introducing to cells. In order to perform this, she has created a small, circular segment of double-stranded DNA that includes the gene of interest as well as a gene for antibiotic resistance. After introducing this segment of DNA to competent bacteria, she plates the bacteria on media containing the antibiotic. Which of the following processes was necessary in order for the bacteria to survive on the plate and contain copies of the gene of interest?", "answer": "Transformation", "options": {"A": "Conjugation", "B": "Transduction", "C": "Transfection", "D": "Transformation", "E": "Transposition"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 27-year-old woman presents to the emergency department with altered mental status. Her parents found her in her room surrounded by pill bottles, alcohol, and illicit drugs 10 minutes ago and promptly brought her in. She was unconscious with lacerations on her wrists. The patient has a past medical history of depression, fibromyalgia, and multiple suicide attempts. Physical exam is notable for a somnolent young woman who responds to questions but is non-compliant in describing the history. She is currently vomiting and her gait seems ataxic. Initial laboratory values are unremarkable. An arterial blood gas analysis reveals the following findings.\n\nArterial blood gas\npH: 7.50\npO2: 105 mmHg\npCO2: 20 mmHg\nBicarbonate: 24 mEq/L\n\nWhich of the following is the most likely intoxication in this patient?", "answer": "Aspirin", "options": {"A": "Acetaminophen", "B": "Alcohol", "C": "Amitriptyline", "D": "Aspirin", "E": "Ethylene glycol"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 33-year-old Asian American man presents to his primary care provider in February with pain in his fingers. His symptoms started 2 years ago and have gradually progressed. He initially attributed his symptoms to stress at work as a social worker. He has tried using ibuprofen, acetaminophen, and naproxen, but these medications did not improve his pain. He also reports that there have been at least 3 instances in the past 2 months in which his fingers became extremely painful and turned white before turning pale blue. These instances occurred when the patient was walking outside. His past medical history is notable for gastroesophageal reflux disease and gout. He takes omeprazole and allopurinol. His temperature is 99°F (37.2°C), blood pressure is 120/78 mmHg, pulse is 90/min, and respirations are 18/min. Physical examination reveals loss of skin fold wrinkles and indurated skin on the palmar side of the digits. Finger range of motion is limited. Which of the following medications is most appropriate to address this patient's concerns?", "answer": "Amlodipine", "options": {"A": "Ambrisentan", "B": "Amlodipine", "C": "Cilostazol", "D": "Lisinopril", "E": "Verapamil"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 3-year-old boy is brought to the physician because of a 1-day history of abdominal pain and frequent urination. His mother reports that the patient has wet his bed overnight and that his urine smelled odd this morning. He has been toilet trained for 4 months and has had very few accidents since then. His last bowel movement was 3 days ago. He was born at term after a normal gestation and has reached all developmental milestones. His parents divorced 4 months ago and the patient's father has moved away. The patient began preschool 6 weeks ago. During this period, he has had two upper respiratory infections that resolved without treatment. His 12-year-old brother has type 1 diabetes mellitus. Vital signs are within normal limits. Physical examination of the abdomen shows mild suprapubic tenderness. Urine dipstick is positive for leukocyte esterase, nitrite, and blood; urinalysis shows white blood cells and gram-negative rods. Which of the following is the most likely predisposing factor for this patient's condition?", "answer": "Constipation", "options": {"A": "Social stressors", "B": "Constipation", "C": "Posterior urethral valves", "D": "Respiratory tract infection", "E": "Family history of diabetes mellitus"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 37-year-old male presents with difficulty eating solids and drinking water; which has been progressively worse over the past year. He has noticed that he is regurgitating food that appears undigested and has also been having difficulty belching. He said that lifting his neck seems to help him keep his food down. He is currently on omeprazole for his acid reflux; however, his heartburn still persists. An esophagogastroduodenoscopy (EGD) is performed that shows no evidence of mechanical obstruction or esophageal inflammation. If esophageal manometry is performed, which of the following will most likely be present in this patient?", "answer": "Aperistalsis in the distal two-thirds of the esophagus with incomplete lower esophageal relaxation", "options": {"A": "Hypomotility of the esophagus with lower esophageal sphincter incompetence", "B": "Aperistalsis in the distal two-thirds of the esophagus with incomplete lower esophageal relaxation", "C": "Normal amplitude, uncoordiated, simultaneous esophageal contractions", "D": "Excessive amplitude or duration of coordinated esophageal contractions", "E": "Hypotensive peristaltic contractions"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 56-year-old man comes to the emergency department for chest pain that started 1 hour ago. He has a history of hypertension, hyperlipidemia, and type 2 diabetes mellitus. He appears diaphoretic and distressed. An ECG shows P waves independent of QRS complexes. The QRS interval is 0.11 seconds with normal morphology. Which of the following is the most likely trigger of this patient's ventricular contractions?", "answer": "Bundle of His", "options": {"A": "Sinoatrial node", "B": "Bachmann bundle", "C": "Bundle of His", "D": "Purkinje fibers", "E": "Ectopic atrial focus\n\""}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 29-year-old pregnant woman is brought to the emergency department complaining of the sudden onset of severe, sharp pelvic pain. She is at 6 weeks’ gestation. The patient is bleeding heavily from the vagina and feels very dizzy. Substantial pain is noted in the lower right quadrant, which intensified towards the end of the physical exam. On examination, there is evidence of abdominal and cervical motion tenderness. Her blood pressure is 71/37 mm Hg, respiratory rate is 21/min, pulse is 117/min, and temperature is 38.4°C (101.1°F). Which of the following is the most appropriate definitive step in the management of this patient?", "answer": "Surgery", "options": {"A": "Surgery", "B": "Methotrexate", "C": "Transvaginal ultrasound", "D": "Abdominal ultrasound", "E": "Serial hCG"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 24-year-old man presents to his primary care physician with heel pain that has been persistent for 3 weeks now. He is bothered by the feeling of significant pressure and swelling in his ankle. He is also having difficulty walking due to pain in his hip. Upon physical examination, there is evidence of swelling and warmth over his Achilles tendon. Imaging of his sacroiliac joint reveals soft tissue involvement and narrowing of the joint spaces. This patient also appears to have a low to moderate kyphosis of his spine. He has no family history of any bone or rheumatological diseases. This patient most likely presents with clinical features of which disease?", "answer": "Ankylosing spondylitis", "options": {"A": "Osteoarthritis", "B": "Ankylosing spondylitis", "C": "Reactive arthritis", "D": "Osteoma", "E": "Fibromyalgia"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 51-year-old man comes to his physician with chronic sinusitis and rhinorrhea for which he uses mometasone nasal spray. He is seeking a refill on this prescription, noting that, although it has not fully relieved his nasal symptoms over the past 2 years, it has helped minimize the severity of those symptoms. On auscultation, there are faint crackles in the bilateral lung fields and an indentation at the nasal bridge. The patient also notes occasional hemoptysis and hematuria. He has no significant medical history and takes no other medications. Family history is significant for rheumatoid arthritis. The physician is suspicious for granulomatosis with polyangiitis and a nasal mucosal biopsy is obtained which confirms the diagnosis. The patient is started immediately on prednisone and cyclophosphamide. Which of the following should also be added to this patient’s therapeutic regimen?", "answer": "Trimethoprim/sulfamethoxazole", "options": {"A": "Azithromycin", "B": "Daptomycin", "C": "Ganciclovir", "D": "Doxycycline", "E": "Trimethoprim/sulfamethoxazole"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 28-year-old man presents to a clinic for a health check-up. He says that he feels great and has not seen a physician for approximately 10 years. He is concerned about his health because his 3 older brothers have recently developed cardiac problems. His medical history is significant for an appendectomy 16 years ago. He works out twice a week and eats a low-salt, well-balanced diet. He drinks alcohol socially on the weekend, but does not use tobacco or drugs. The pulse is 80/min, respirations are 14/min, and the blood pressure is 129/80 mm Hg. The physical examination is unremarkable. Laboratory testing shows the following:\nSerum Glucose (fasting) 100 mg/dL\n  Sodium 142 mEq/L\n  Potassium 3.9 mEq/L\n  Chloride 101 mEq/L\nSerum Creatinine 0.8 mg/dL\nBlood Urea Nitrogen 10 mg/dL\nCholesterol, total 250 mg/dL\n  HDL-cholesterol 34 mg/dL\n  LDL-cholesterol 210 mg/dL\nTriglycerides 160 mg/dL\nThe patient is most likely started on a medication which acts by which of the following mechanism?", "answer": "Inhibition of HMG-CoA reductase", "options": {"A": "Blockage of beta-adrenergic receptors", "B": "Blockage of the angiotensin receptors", "C": "Increase loss of bile acids in the feces", "D": "Inhibition of angiotensin converting enzyme", "E": "Inhibition of HMG-CoA reductase"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 17-year-old boy presents for a psychotherapy session after finding out that his girlfriend has been carrying on another relationship with someone else. He expresses rage and complains of difficulty focusing on his upcoming high school comedy club routines and upcoming track meet. His therapist, while explaining the concept of defense mechanisms, describes some hypothetical examples related to the situation. Which of the following potential actions by this patient would be an example of sublimation?", "answer": "Channeling his anger about the situation into training for his track meet", "options": {"A": "Channeling his anger about the situation into training for his track meet", "B": "Instigating a physical fight with his girlfriend’s other partner", "C": "Making jokes about the situation and incorporating them into his comedy routine", "D": "Not thinking about the upsetting situation now or in the future", "E": "Not thinking about the upsetting situation until after his track meet, then confronting and processing his feelings about it"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 39-year-old woman is brought to the emergency room by her fiancé for severe abdominal pain for the past 5 hours. She was watching TV after dinner when she felt a sudden, sharp, 10/10 pain at the epigastric region that did not go away. Ibuprofen also did not help. She reports recurrent abdominal pain that would self-resolve in the past but states that “this one is way worse.” Her past medical history is significant for diabetes and an appendectomy 2 years ago. The patient endorses nausea and 1 episode of emesis, but denies fevers, chills, chest pain, shortness of breath, diarrhea, constipation, urinary symptoms, paresthesia, or weakness. She used to smoke marijuana in college and drinks about 2 beers a week. A physical examination demonstrates an overweight woman in acute distress with diffuse abdominal tenderness. Her vitals are within normal limits. Laboratory values are shown below:\n\nHemoglobin: 12 g/dL\nHematocrit: 34%\nLeukocyte count: 4,900/mm^3 with normal differential\nPlatelet count: 160,000/mm^3\n\nSerum:\nNa+: 138 mEq/L\nCl-: 98 mEq/L\nK+: 4.8 mEq/L\nHCO3-: 25 mEq/L \nGlucose: 123 mg/dL\nCa2+:  6.9 mg/dL\nAST: 387 U/L\nALT: 297 U/L\nALP: 168 U/L\nLipase: 650 U/L (Normal 0 – 160 U/L)\n\nWhat is the best next step in the workup of this patient?", "answer": "Abdominal ultrasound", "options": {"A": "Abdominal computed tomography with IV contrast", "B": "Abdominal computed tomography without IV contrast", "C": "Abdominal magnetic resonance imaging", "D": "Abdominal ultrasound", "E": "Upright chest and abdominal radiograph"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 50-year-old man is evaluated for a 2-year history of intermittent, nonproductive, chronic cough, as well as mild dyspnea with exertion. He has a 20-pack-year history of smoking and is a current smoker. His medical history is significant for hypertension and type 2 diabetes mellitus, which he has controlled with diet and exercise. He also takes lisinopril. On physical examination, blood pressure is 125/76 mm Hg, pulse rate is 78/min, respiratory rate is 15/min, oxygen saturation is 98% (breathing room air), and his BMI is 25 kg/m2. There is no jugular venous distention. Heart sounds are normal, and there is no murmur. Auscultation of the lungs reveals faint, bilateral wheezing. No peripheral edema is noted. The remainder of the examination is normal. Which of the following is most likely to confirm the diagnosis for this patient?", "answer": "Spirometry", "options": {"A": "Chest CT scan", "B": "Measurement of protease inhibitor", "C": "Arterial blood gases (ABG)", "D": "Spirometry", "E": "Cardiac catheterization"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 51-year-old woman presents with bilateral hand tremors. She has had these tremors for several years, and her symptoms have gradually worsened over time. The tremors are restricted to her hands and are most prominent when she is holding a cup of tea or a pen. The tremors get worse when she is under stress or exhausted, and they are starting to disrupt her work routine. She denies walking difficulties, speech problems, and weakness. Her past medical history is significant for a recent hospitalization for an asthma exacerbation. Current medications include salmeterol, medium-dose fluticasone, and a daily multivitamin. The patient denies smoking but drinks alcohol socially. The patient is afebrile and her vital signs are within normal limits. On physical examination, her hands have a noticeable tremor when in use and remain still while resting in her lap. Which of the following is the best course of treatment for this patient?", "answer": "Primidone", "options": {"A": "Baclofen", "B": "Levodopa-carbidopa", "C": "Primidone", "D": "Propranolol", "E": "Sodium valproate"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 39-year-old female was involved in a head-on collision motor vehicle accident. If she was found to have a traumatic rupture of the aorta, where along the path of the aorta is the most common site of injury?", "answer": "Aortic isthmus", "options": {"A": "Ascending aorta", "B": "Site of attachment of ligamentum arteriosum", "C": "Aortic isthmus", "D": "Descending aorta - Thoracic aorta", "E": "Abdominal aorta"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A previously healthy 2-month-old boy is brought to the physician because of a 10-day history of poor feeding. He used to feed for 20 minutes but now needs 40 minutes. He struggles to breathe and sweats while feeding. He was born at 38 weeks' gestation. He is at the 20th percentile for length and 10th percentile for weight. His vital signs are within normal limits. Pulse oximetry on room air shows an oxygen saturation of 98%. A grade 3/6 holosystolic murmur is heard at the left lower sternal border. An ECG shows left-axis deviation. An x-ray of the chest shows an enlarged left atrium and ventricle and increased pulmonary vascular markings. Doppler echocardiography confirms the presence of an intracardiac shunt. Which of the following is the most likely explanation for the direction of flow of blood across this shunt?", "answer": "Decrease in pulmonary vascular resistance", "options": {"A": "Closure of the ductus arteriosus", "B": "Communication between the right and left atria", "C": "Right ventricular outflow tract obstruction", "D": "Increase in pulmonary vascular resistance", "E": "Decrease in pulmonary vascular resistance"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 14-year-old boy is brought to the physician for a follow-up examination. He has allergic rhinitis and his only medication is cetirizine. He is at the 60th percentile for height and above the 95th percentile for weight and BMI. Vital signs are within the normal limits. Examination shows a slightly tender, firm, 1-cm subareolar mass in the left breast. There are no changes in the skin or nipple. The right breast is unremarkable. There is no palpable axillary lymphadenopathy. Axillary and pubic hair is present. Examination of the penis and testis shows no abnormalities. Neurologic examination shows no focal findings. Which of the following is the most likely cause of this patient's findings?", "answer": "Physiological development", "options": {"A": "Adverse drug reaction", "B": "Leydig cell tumor", "C": "Hyperthyroidism", "D": "Ductal ectasia", "E": "Physiological development"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 54-year-old woman presents to her primary care physician complaining of a lump in her right breast. She first noticed it 1 month ago. Now she is worried that it may have grown. She claims that the lump is not painful or itchy, and she denies any abnormal nipple bleeding or discharge. She has a family history of breast cancer, including both her mother and older sister. Physical examination reveals a firm, immobile lump in the upper right breast. A mammogram is performed, which identifies an irregular mass with a fibrotically stranded border. A biopsy is performed that is positive for invasive ductal carcinoma. The patient is started on radiation induction therapy and scheduled for a modified radical mastectomy. Following tumor gene testing, the patient is found to be positive or the HER-2/neu oncogene. Which of the following should be started post-mastectomy to improve the patient’s prognosis?", "answer": "Trastuzumab", "options": {"A": "Anastrozole", "B": "Corticosteroids", "C": "Leuprolide", "D": "Tamoxifen", "E": "Trastuzumab"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 48-year-old man presents to his primary care physician concerned about his weight. He states he has been gaining weight though does not feel he has changed his diet. The patient also states he has felt fatigued lately and not himself. He denies taking any medications or using any illicit substances at baseline. His temperature is 99.2°F (37.3°C), blood pressure is 177/108 mmHg, pulse is 100/min, respirations are 18/min, and oxygen saturation is 98% on room air. Physical exam is notable for an obese man with striae on his abdomen. A 24-hour urine free cortisol is collected and demonstrates an elevated cortisol level; however, a high dose of dexamethasone when administered results in no attenuation of cortisol release. A CT scan of the abdomen is within normal limits. Which of the following is associated with the most likely diagnosis?", "answer": "History of smoking", "options": {"A": "Adrenal adenoma", "B": "Decreased ACTH level", "C": "Enlargement of the facial bones", "D": "History of smoking", "E": "Increased personal stress and poor sleep habits"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "Advances in molecular biology have identified important factors and sequences required for transcription and translation of mRNA as well as multiple diseases associated with mutations. The Kozak sequence is one such finding from this research. What is the Kozak consensus sequence?", "answer": "An initiator of translation proximal to the start codon", "options": {"A": "A sequence box that binds to NF-1", "B": "A 25-base upstream promoter of transcription", "C": "An untranslated region downstream of the the stop codon", "D": "An initiator of translation proximal to the start codon", "E": "A site to which the 50S ribosome binds"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 3-week-old male infant is brought to the physician by his parents because they noticed that his head has been tilted to the left since birth. Physical examination shows the head turned toward the left side and the chin rotated toward the right. He cries during an attempt to rotate the head to the right. There is a firm, well-circumscribed mass on the left lower side of the neck. Which of the following is the strongest predisposing factor for this patient's condition?", "answer": "Fetal macrosomia", "options": {"A": "Fetal macrosomia", "B": "Cesarean delivery", "C": "Intrauterine exposure to haloperidol", "D": "Polyhydramnios", "E": "Preterm birth"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 13-month-old boy was brought to the clinic due to failure-to-thrive and mental impairment. Retinal findings are shown in the picture. The parents are healthy, but they previously had a child who died at 14 months of age. What is the most likely cause for the underlying abnormalities?", "answer": "Lysosomal enzyme mutation", "options": {"A": "Structural protein mutation", "B": "Genomic imprinting", "C": "Lysosomal enzyme mutation", "D": "Robertsonian translocation", "E": "Mitochondrial gene mutation"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 24-year-old woman who is 16 weeks pregnant comes to your office requesting a referral for an abortion. Upon questioning she states that she is scared that her baby will be \"deformed\" because on routine screening she was found to have an elevated level of alpha-fetoprotein. What is the most likely cause of this lab abnormality in this patient?", "answer": "Inaccurate gestational age", "options": {"A": "Trisomy 13", "B": "Trisomy 18", "C": "Trisomy 21", "D": "Neural tube defect", "E": "Inaccurate gestational age"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A previously healthy 45-year-old man is brought to the emergency department after being found by a search and rescue team in the mountains. He has been without food or water for 30 hours. His temperature is 37°C (98.6°F), pulse is 123/min, respirations are 20/min, and blood pressure is 90/55 mm Hg. Physical examination shows decreased skin turgor and dry mucous membranes. Evaluation of this patient's urine before treatment is initiated is most likely to show which of the following?", "answer": "Low urine sodium with hyaline casts", "options": {"A": "High urine urea with granular casts", "B": "Low urine sodium and low urine osmolality", "C": "Low urine sodium with hyaline casts", "D": "High urine protein with fatty casts", "E": "Low urine osmolality with RBC casts"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 14-year-old Caucasian male presents with painful erythematous and honey-colored crusted lesions around his mouth. Culture of the lesions reveals gram-positive cocci in clusters. Further analysis reveals bacteria that are beta-hemolytic, coagulase positive, catalase positive, and appear golden on the blood agar plate. Which of the following helps the bacterium in this infection bind to immunoglobulin and prevent phagocytosis when invading its host?", "answer": "Protein A", "options": {"A": "Protein A", "B": "Staphylokinase", "C": "Exfoliatin A", "D": "Protein M", "E": "Neurotoxin"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 70-year-old man comes to the physician for the evaluation of abdominal pain over the past month. The patient describes epigastric pain that radiates to the back. He also reports a 10-kg (22-lb) weight loss over the past 6 months. He has a history of untreated type 2 diabetes mellitus. He has not seen a doctor in 15 years. He is retired and spends most of his time at home watching TV. He rarely cooks and mainly eats fast food. He has smoked one pack of cigarettes daily for the past 50 years. He drinks 2–3 cans of beer per day. He appears pale. His temperature is 37°C (98.6°F), pulse is 80/min, and blood pressure is 150/90 mm Hg. Physical examination shows jaundice of the conjunctivae and the skin. The abdomen is soft, with no rebound or guarding. Laboratory studies show a serum glucose concentration of 260 mg/dL. Abdominal sonography shows enlargement of the gallbladder. Which of the following is most likely to have contributed to this patient's condition?", "answer": "Smoking history", "options": {"A": "Smoking history", "B": "Lack of physical activity", "C": "Poor dietary habits", "D": "History of alcohol use", "E": "Diabetes mellitus"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 63-year-old African American man with a history of hypertension and dyslipidemia presents to the emergency department with facial swelling and difficulty breathing. Symptoms began suddenly that morning and continued to worsen. He started taking lisinopril several weeks ago. His blood pressure is 110/74 mm Hg, heart rate is 94/min, and respiratory rate is 20/min. Physical examination is notable for swelling of his lips and inspiratory stridor. Clinical lab results suggest a normal C1 esterase inhibitor level. Of the following options, which is the most likely diagnosis?", "answer": "Drug-induced angioedema", "options": {"A": "Scleredema", "B": "Erysipelas", "C": "Facial lymphedema", "D": "Drug-induced angioedema", "E": "Contact dermatitis"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 21-year-old female college student comes to the physician because of a two-week history of vaginal itching and burning. She also noticed white vaginal discharge despite cleaning her genital area daily using a \"\"soap-free, natural\"\" vaginal douche. She is worried that she might have contracted a sexually transmitted disease after meeting her new boyfriend around one month ago. She has type 1 diabetes mellitus. The patient swims for the college swimming team. She had an intrauterine device implanted 3 months ago and does not use barrier protection. She smokes one pack of cigarettes per day and does not drink alcohol. Speculum examination shows an erythematous vagina covered in copious white discharge. Her vaginal pH is 4.4 and the microscopic image of a KOH preparation shows multiple pseudohyphae. Which of the following is the greatest predisposing factor for this patient's condition?\"", "answer": "Diabetes mellitus", "options": {"A": "Smoking history", "B": "Frequent vaginal douching", "C": "Unprotected sexual intercourse", "D": "Intrauterine device", "E": "Diabetes mellitus"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 72-year-old female recently fractured her hip in a fall. She suffers from regular joint pain in her fingers, and hip X-rays reveal low bone mineral density. She has a history of diabetes mellitus and was diagnosed 2 years ago with end-stage renal disease. Serum phosphate levels are markedly elevated. Which of the following likely contributes to her orthopedic problems?", "answer": "Increased serum parathyroid hormone", "options": {"A": "Decreased serum aldosterone", "B": "Increased serum parathyroid hormone", "C": "Increased serum glucose", "D": "Chronic hypertension", "E": "Chronic hypovolemia"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 52-year-old man presents to his primary care physician for his annual check-up. He says that he has no health concerns; however, his wife is concerned that he has become increasingly forgetful. For example, he has become forgetful during his daily activities and recently has been getting lost during errands like shopping. She says that these symptoms have been occurring for about a year. She says that she became alarmed when he started forgetting the names of their children. Finally, over the last month he has become more irritable, which has led to several confrontations at work. Based on the age of onset for his disease, the patient is referred for genetic testing. Which of the following chromosomes contain genes that may be mutated in this patient's disease?", "answer": "1", "options": {"A": "1", "B": "4", "C": "6", "D": "18", "E": "20"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 23-year-old woman, gravida 2, para 1, at 13 weeks gestation, comes to the physician because of a 2-day history of burning pain during urination. She has been sexually active with different male partners during the pregnancy and did not use condoms. She has not had any fever, chills, or pelvic pain. Physical examination shows thick, purulent discharge from the urethra. Urine dipstick shows leukocyte esterase, urinalysis shows 10 WBCs/hpf, and Gram stain of the urethral swab shows polymorphonuclear leukocytes with intracellular gram-negative diplococci. Pelvic ultrasound shows a viable intrauterine pregnancy. Which of the following is the most appropriate treatment?", "answer": "Intramuscular ceftriaxone and oral azithromycin\n\"", "options": {"A": "Oral levofloxacin", "B": "Oral cefixime and oral doxycycline", "C": "Intramuscular ceftriaxone", "D": "Oral erythromycin", "E": "Intramuscular ceftriaxone and oral azithromycin\n\""}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 20-year-old college student is brought to his primary care physician by his parents over the New Years holiday because they are concerned about his behavior since right after high school graduation in May the spring before. Prior to this year, he was generally an outgoing and social young man, who now reportedly has been spending the majority of his time alone in his dorm room and room at home, where his mother and father have overheard him talking to other people when he has no guests. When asked if anything was bothering him at school, he reports that at night the voice of the school's mascot encourages him to save the school from the large oak grove that will soon takeover the student union building by setting the trees on fire for all to see. On exam, his appears to be otherwise healthy and his urine toxicology screen is negative. What is the most likely diagnosis?", "answer": "Schizophrenia", "options": {"A": "Schizoaffective disorder", "B": "Major depression", "C": "Schizophrenia", "D": "Schizophreniform disorder", "E": "Malingering"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 58-year-old man comes to the physician for evaluation of an increasing left-sided cheek swelling and recurrent oral ulcers for 1 year. He has smoked a pack of cigarettes daily for 25 years. Examination shows a mild, nontender swelling above the angle of the left jaw. An ultrasound-guided biopsy of the mass confirms the diagnosis of parotid adenoid cystic carcinoma. A left-sided total parotidectomy is performed. This patient is at greatest risk for which of the following complications?", "answer": "Inability to wrinkle the left side of the forehead", "options": {"A": "Hyperesthesia of the left ear lobe", "B": "Impaired taste of the posterior 1/3 of the tongue", "C": "Flushing of the right cheek while eating", "D": "Inability to wrinkle the left side of the forehead", "E": "Hyperacusis of the left ear"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 34-year-old man comes to the physician for a routine health maintenance examination required for his occupation as a school bus driver. He feels well and healthy. Upon questioning, he reports that he has smoked 2 joints of marijuana every night after work for the past year for recreational purposes. He typically smokes 5 joints or more on weekends. Which of the following responses by the physician is the most appropriate?", "answer": "\"\"\"Have you ever experienced a situation in which you wished you smoked less marijuana?\"\"\"", "options": {"A": "\"\"\"Let me know when you are ready to stop smoking marijuana. We can talk about specific strategies to help you quit at that time.\"\"\"", "B": "\"\"\"Have you ever experienced a situation in which you wished you smoked less marijuana?\"\"\"", "C": "\"\"\"When did you start being dependent on marijuana consumption?\"\"\"", "D": "\"\"\"We have a great program to help patients with substance use disorder issues. Let me give you more information about specific details.\"\"\"", "E": "\"\"\"You should stop smoking marijuana because it is not good for your health.\"\"\""}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 6-year-old girl of Moroccan descent is brought to the pediatrician by her father who is concerned about the child developing a body odor. He reports that she has started to smell “like a teenage boy” especially after physical activity. The child has had limited medical follow-up since being born in Morocco and immigrating to the United States at 3 years of age. Her temperature is 99°F (37.2°C), blood pressure is 150/90 mmHg, pulse is 85/min, and respirations are 18/min. On exam, she has hair in her axillary and pubic regions. Genital examination demonstrates clitoral enlargement and labioscrotal fusion. Which of the following metabolites is most likely elevated in this patient?", "answer": "11-deoxycorticosterone", "options": {"A": "Aldosterone", "B": "Corticosterone", "C": "Cortisol", "D": "11-deoxycorticosterone", "E": "Leutenizing hormone"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 25-year-old woman presents to the clinic for burning with urination. She is a newlywed and reports 3 similar episodes within the past 4 months. She claims that since yesterday she has noticed a burning sensation whenever she urinates, an increase in urinary frequency, and some clear vaginal discharge. She denies fever, chills, back pain, or chest pain. Her past medical history is significant for chlamydia that was adequately treated 3 years ago. She is currently sexually active with her husband and has an IUD. She is subsequently prescribed a course of nitrofurantoin for her symptoms. While getting up to leave, the patient asks “why is it that I always get these symptoms but my husband is fine?” What is the most appropriate answer to this patient’s question?", "answer": "The female urethra is shorter", "options": {"A": "Her partner is an asymptomatic carrier", "B": "Inadequate treatment of her prior episodes", "C": "The female urethra is shorter", "D": "The patient is experiencing recurrence of her past chlamydial infection", "E": "There is no explanation"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 17-year-old boy comes to the physician 1 week after noticing a lesion on his penis. There is no history of itching or pain associated with the lesion. He is sexually active with two female partners and uses condoms inconsistently. Five weeks ago, he returned from a trip to the Caribbean with some of his football teammates. He takes no medications. He has recently started an intense exercise program. His vital signs are within normal limits. Physical examination shows multiple enlarged, nontender lymph nodes in the inguinal area bilaterally. A photograph of the lesion is shown. Which of the following is the most likely pathogen?", "answer": "Treponema pallidum", "options": {"A": "Trichophyton rubrum", "B": "Mycoplasma genitalium", "C": "Human papillomavirus", "D": "Treponema pallidum", "E": "Herpes simplex virus type 2"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 36-year-old man presents to a physician for a post-transplant medical evaluation. He has been taking prednisone and azathioprine for the last 6 months after receiving a cadaveric renal transplant. He complains of fever, cough, and anorexia for the last 6-7 days. His cough is productive of thick sputum. His temperature is 38.5°C (101.5°F). The physical examination is significant for diminished breath sounds over the left lower lung with dullness on percussion and increased vocal resonance. A left lower lobe nodule, 5 cm (2 in) in diameter with eccentric central cavitation, is visible on the chest X-ray. A sputum analysis reveals branched, irregular, gram-positive filamentous rods. Which of the following constitutes the first-line therapy in this patient?", "answer": "Sulfisoxazole", "options": {"A": "Erythromycin", "B": "Ceftazidime", "C": "Penicillin", "D": "Sulfisoxazole", "E": "Tobramycin"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 54-year-old woman presents to her gynecologist complaining of incontinence. She reports leakage of a small amount of urine when she coughs or laughs as well as occasionally when she is exercising. She denies any pain with urination. She underwent menopause 2 years ago and noted that this problem has increased in frequency since that time. Her history is significant only for three uncomplicated pregnancies with vaginal births. Urinalysis, post-void residual, and cystometrogram are conducted and all show normal results. The patient's vital signs are as follows: T 37.5 C, HR 80, BP 128/67, RR 12, and SpO2 99%. Physical examination is significant for pelvic organ prolapse on pelvic exam. Which of the following is a reasonable first step in the management of this patient's condition?", "answer": "Kegel exercises", "options": {"A": "Kegel exercises", "B": "Imipramine", "C": "Bethanechol", "D": "Urethropexy", "E": "Tension-free vaginal tape"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "Researchers from a public health institute located in the United States conducted a multicenter cohort study on a large number of elderly individuals in order to evaluate the protective effect of the new vaccine for herpes zoster (commonly known as shingles) reactivation. After a long follow-up period, the data shows that shingles developed in 15% of study participants who received the new vaccine compared to 20% of diseased study participants in the control group that did not receive the vaccine. If the new vaccine showed identical efficacy in groups with higher and lower risks of herpes zoster reactivation (e.g., 40% and 10% risk), the calculated protective proportion of 25% would be maintained, regardless of the different baseline risk for shingles development. What is this metric also known as?", "answer": "Relative risk reduction", "options": {"A": "Event rate", "B": "Risk difference", "C": "Attributable difference", "D": "Relative risk reduction", "E": "Absolute risk reduction"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 55-year-old gentleman has been working in a sand blasting factory for over 25 years. He presents to his primary care physician with what he describes as increasing shortness of breath. PFTs are performed describing a restrictive lung process. Which of the following has most likely been the long-term mechanism of his disease development?", "answer": "Phagocytosis of silica", "options": {"A": "Eosinophilic reaction", "B": "Phagocytosis of silica", "C": "Tuberculosis", "D": "Primary lung cancer", "E": "Defective mucociliary transport"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 37-year-old man presents to the emergency department with acute loss of vision, slurred speech, and agitation. Past medical history is significant for HIV and hepatitis C, diagnosed 10 years ago for which he is non-compliant with medication. A T1 MRI of the brain shows asymmetric, hypointense white matter lesions. Which of the following pathogens is most likely responsible for this patient’s opportunistic infection?", "answer": "JC virus", "options": {"A": "Mycobacterium avium complex", "B": "Herpes virus 8", "C": "Candida albicans", "D": "JC virus", "E": "Pneumocystis jirovecii"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 4-year-old girl is brought to the physician for evaluation of a rash that her mother noticed 5 months ago. The rash is not painful or itchy but she notices that her daughter sometimes picks at the “spots.” The girl's 2-year-old brother has also started developing similar skin lesions over the past month. The patient has no history of serious illness and takes no medications. She is in the 75th percentile for height and 50th percentile for weight. A photograph of the patient's rash is shown. Which of the following infectious agents is the most likely cause of this patient's skin condition?", "answer": "Poxvirus", "options": {"A": "Human herpesvirus 8", "B": "Human papillomavirus", "C": "Herpes simplex virus 1", "D": "Poxvirus", "E": "Varicella-zoster virus"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 51-year-old police officer is brought to the emergency room after being shot in the abdomen. His wound was packed and bandaged by emergency medical services before he was transported to the hospital. His past medical history is notable for hypertension and diabetes. He takes metformin and lisinopril. He has a 20-pack-year smoking history and does not drink alcohol. His temperature is 98.6°F (37°C), blood pressure is 142/86 mmHg, pulse is 120/min, and respirations are 24/min. On exam, he appears uncomfortable but is able to answer questions appropriately. He has a 1 cm x 1 cm wound in the left upper quadrant. There is an exit wound in the left lower back. After undergoing the appropriate laboratory and imaging tests, he undergoes a diagnostic laparotomy. No involvement of the colon or small intestine is noted intraoperatively. He is placed on the appropriate antibiotic and pain control regimens. Three days later, he experiences several episodes of non-bloody diarrhea. His temperature is 101°F (38.3°C). Sigmoidoscopy reveals multiple pseudomembranous plaques in the sigmoid and descending colon. This patient's symptoms are most likely due to taking an antibiotic that inhibits which of the following enzymes?", "answer": "50S ribosomal subunit", "options": {"A": "30S ribosomal subunit", "B": "50S ribosomal subunit", "C": "Dihydropteroate synthetase", "D": "DNA-dependent RNA polymerase", "E": "DNA gyrase"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 3-year-old girl is brought to the physician by her parents for the evaluation of vaginal discharge for one month. The discharge is foul-smelling and contains some blood. The patient sometimes has pain with urination. She has not had increased urinary frequency or abdominal pain. Topical vaginal cream application did not improve the patient's symptoms. There is no personal or family history of serious illness. She lives with her parents and attends a local daycare center. Vital signs are within normal limits. Examination of the vulva and vaginal entrance shows an intact hymen, vaginal erythema with blood-tinged, foul-smelling discharge, and the tip of a white object. The remainder of the examination shows no abnormalities. Which of the following is the most appropriate next step in the management of this patient?", "answer": "Vaginal irrigation with warm saline", "options": {"A": "Vaginal irrigation with warm saline", "B": "Colposcopy", "C": "Vacuum suction", "D": "Alert Child Protective Services", "E": "Administration of oral metronidazole"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 60-year-old man comes to the physician because of a 3-month history of a slowly enlarging painless ulcer on his lower lip. One year ago he had a painful rash near his upper lip that resolved completely with acyclovir therapy. He has a 10-year history of type 2 diabetes mellitus treated with metformin. He has worked in construction for the past 33 years. He has smoked one pack of cigarettes daily for 35 years. Examination shows a 0.5 x 0.5 cm nontender ulcer with everted edges on the midline of his lower lip. The erythematous ulcer bleeds upon palpation. He has numerous moles of varying sizes all over his body. There are no palpable cervical lymph nodes. Which of the following is the most likely diagnosis?", "answer": "Squamous cell carcinoma", "options": {"A": "Squamous cell carcinoma", "B": "Aphthous stomatitis", "C": "Psoriasis", "D": "Seborrheic keratosis", "E": "Actinic keratosis\n\""}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 3-year-old girl is brought to the pediatrician by her father for fever and cough. The patient’s father states that she had a sore throat and runny nose 2 weeks ago. Then last night she developed a productive cough and a fever. The father is worried that this is pneumonia again, and reports that she has been hospitalized 5 times already with pneumonia. Her medical history is also significant for chronic diarrhea. The father reports that the patient has 2 older brothers who are both healthy. The patient’s temperature is 102°F (38.9°C), blood pressure is 102/60 mmHg, pulse is 110/min, and respirations are 28/min with an oxygen saturation of 94% on room air. On physical examination, decreased breath sounds are appreciated on the right. A chest radiography shows consolidation in the right upper lobe, consistent with pneumonia. An antibody panel and flow cytometry are obtained in the setting of the patient’s recurrent infections. The results show a normal lymphocyte count with low levels of IgA, IgG, and IgE and elevated levels of IgM. Which of the following is the patient most at risk for developing?", "answer": "Blurry vision", "options": {"A": "Ataxia", "B": "Atopic dermatitis", "C": "Blurry vision", "D": "Lymphoma", "E": "Scant tonsils"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 72-year-old man presents with urinary frequency resulting in frequent awakening to urinate at night. He is a retired elite runner and does not have a history of any chronic medical conditions. The patient denies weight loss, bone pain, or pain with urination. The patient is not in distress. Vitals show: temperature 36.8°C (98.2°F), heart rate 98/min, respiratory rate 15/min, and blood pressure 100/75 mm Hg. Physical exam is significant for a smooth, non-tender, uniformly enlarged prostate on digital rectal exam. There is no CVA tenderness. CBC, CMP, urinalysis, and abdominal ultrasound are ordered. Significant findings include: bilateral hydronephrosis on ultrasound, BUN/creatinine > 20:1, specific gravity > 1,020, FENa < 1%, urine Na < 20, and urine osmolality > 450 mOsm/kg. Furthermore, post-void residual volume is > 100 mL. Which type of patient would least likely have these same diagnostic findings?", "answer": "A 35-year-old woman with severe colicky pain radiating to the left flank", "options": {"A": "A 55-year-old Egyptian man with painless hematuria, 18.1 kg (40 lb) incidental weight loss and confirmed Schistosoma hematobium infection", "B": "A 27-year-old woman with waxing and waning internuclear ophthalmoplegia, scanning speech, and optic neuritis", "C": "An ICU patient with a kinked Foley catheter", "D": "A multiparous obese woman presenting with urinary incontinence, pelvic fullness, and a vaginal bulge", "E": "A 35-year-old woman with severe colicky pain radiating to the left flank"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "An 82-year-old man with Alzheimer disease is brought to the physician by his daughter because of extensive bruising on his arms. He lives in an assisted living facility. Physical examination shows large ecchymoses across both forearms and upper arms in varied stages of healing. His hemoglobin concentration is 11.7 g/dL, mean corpuscular volume is 78 μm3, and platelet count is 180,000/mm3. Coagulation studies are within normal limits. Which of the following is the most likely etiology of his bruises?", "answer": "Nonaccidental trauma", "options": {"A": "Platelet aggregation inhibition", "B": "Intravascular coagulation with fibrinolysis", "C": "Increased activity of epidermal melanocytes", "D": "Nonaccidental trauma", "E": "Vitamin K deficiency"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 23-year-old woman presents to her gynecologist for a routine visit. She is nulliparous, does not report any gynecologic or systemic diseases, and has no complaints. She is sexually active with one partner and uses oral contraceptive pills. Her vital signs are as follows: blood pressure 125/70 mm Hg, heart rate 81/min, respiratory rate 12/min, and temperature 36.6℃ (97.9℉). The physical examination is within normal limits. The breast examination is normal. No pathology is noted in the external genitalia and a speculum examination reveals a normal cervix with a closed external os and no discharge. A specimen is obtained from the cervical portion for a Pap smear. On bimanual examination, the uterus is normal size, non-tender, and mobile adnexa is non-palpable.\nThe pap smear result is as follows:\nThe pap smear result is as follows:\nSpecimen adequacy: satisfactory for evaluation\nInterpretation: negative for intraepithelial lesion or malignancy\nNotes: absent transformation zone component\nHow should we proceed with the management of this patient?", "answer": "Repeat Pap test in 3 years as a usual screening schedule suggests", "options": {"A": "Repeat Pap test in 3 years as a usual screening schedule suggests", "B": "Repeat Pap test within 2 weeks and ensure proper sampling from the transformation zone", "C": "Perform a screening test for high-risk human papillomavirus (HPV)", "D": "Recommend genotyping for HPV types 16 and 18", "E": "Perform a HPV testing and Pap smear in one year"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 57-year-old woman presents to the emergency department with acute pain in the left lower abdomen associated with nausea and vomiting for the past 24 hours. Prior to this episode, the patient did not have any significant gastrointestinal (GI) problems except for occasional constipation and indigestion after heavy meals. She has had hypertension and hypercholesterolemia for the past 7 years. Her family history is negative for GI disorders. Vital signs include a temperature of 38.0°C (100.4°F), blood pressure of 120/80 mm Hg, and pulse of 85/min. On physical examination, there is tenderness in the left lower abdominal quadrant. Abdominal CT scan shows thickening of the bowel wall and streaky mesenteric fat. Which of the following best describe the primary disorder in this patient?", "answer": "Herniation of mucosa and submucosa through the muscular layer of the colon", "options": {"A": "Obstruction of the lumen of the appendix", "B": "Decreased blood flow to the GI tract", "C": "Inflammation of the renal parenchyma, calyces and pelvis", "D": "Herniation of mucosa and submucosa through the muscular layer of the colon", "E": "Inflammation of the upper genital tract"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 35-year-old woman comes to the emergency department because of a 3-day history of pain in the left cheek. The pain occurs every few hours, lasts 30–60 seconds, and is aggravated by chewing and brushing. She has a history of pain with a vesicular rash in the right axillary area one year ago. She had an upper respiratory infection 2 weeks ago. Physical examination shows no abnormalities. Which of the following is the most likely diagnosis?", "answer": "Trigeminal neuralgia", "options": {"A": "Cluster headache", "B": "Trigeminal neuralgia", "C": "Postherpetic neuralgia", "D": "Sinus headache", "E": "Temporal arteritis"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 45 year old male presents to clinic complaining of a ringing in his ears. The patient's vitals are: BP 120/65, RR 16, 100% on room air, HR 78 bpm and he appears to be in no acute distress. Upon obtaining a history you learn that this patient also complains that at times the \"room feels like it's spinning.\" You also notice throughout the interview that you have to speak loudly as the patient has difficulty hearing. The patient is then lost to follow up for his current condition. The patient returns several years later with worsening symptoms and as part of this patient's workup a MRI is obtained (Image A). Which of the following chromosomes is most likely mutated in association with this patient's condition?", "answer": "Chromosome 22", "options": {"A": "Chromosome 13", "B": "Chromosome 7", "C": "Chromosome 17", "D": "Chromosome 22", "E": "The X chromosome"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 35-year-old is brought into the emergency room after a bicycle vs motored vehicle accident. He was unconscious after hitting the side of his head on the road, but recovered consciousness after a few minutes. He started to ride his bicycle again, but then developed a severe headache with nausea and vomiting, at which time he called EMS. While in the hospital, the patient is confused and cannot provide a history. He quickly loses consciousness and his CT scan is displayed in Figure 1. What is the most likely diagnosis?", "answer": "Epidural hematoma", "options": {"A": "Subarachnoid hemorrhage", "B": "Subdural hematoma", "C": "Epidural hematoma", "D": "Subgaleal hematoma", "E": "Caput succedaneum"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 39-year-old man comes to the physician because of a 2-month history of shortness of breath with exertion. He immigrated to the United States from Ghana 20 years ago. His pulse is 88/min, respirations are 18/min, and blood pressure is 120/80 mm Hg. Echocardiography shows thickened mitral valve leaflets with reduced motion and a narrowed mitral valve orifice diameter. Which of the following auscultation findings is most likely to correlate with the severity of this patient's valvular disease?", "answer": "Decreased time between S2 and opening snap", "options": {"A": "Decreased time between S2 and opening snap", "B": "Presence of a mid-systolic click", "C": "Radiation of murmur to the axilla", "D": "Increased intensity of the murmur", "E": "Absence of A2 heart sound"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 6-year-old boy is brought to the physician because of worsening fatigue for the past 4 weeks. Examination of the head and neck shows conjunctival pallor, grayish-brown spots on the irises, prominent epicanthal folds, and a broad nasal bridge. He has a single transverse palmar crease, and there are scattered petechiae over the chest. An ultrasound of the abdomen shows enlargement of the liver and spleen. Analysis of the bone marrow aspirate of this patient is most likely to show which of the following findings?", "answer": "CD10 positive cells", "options": {"A": "Translocation t(15;17)", "B": "Clusters of plasma cells", "C": "Ringed sideroblasts", "D": "CD10 positive cells", "E": "Hypocellular bone marrow"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 42-year-old female presents to the emergency department with two days of severe abdominal pain and fever. The patient has a history of gallstones, for which she was scheduled to have a cholecystectomy in two weeks. On physical exam, her abdomen is tender to palpation over the epigastrium, without rebound or guarding. The patient is noticeably jaundiced. Laboratory evaluation is notable for a leukocytosis and a total bilirubin of 6.4 mg/dL. What is the diagnosis in this patient?", "answer": "Acute cholangitis", "options": {"A": "Acute cholecystitis", "B": "Acute pancreatitis", "C": "Chronic pancreatitis", "D": "Acute cholangitis", "E": "Primary sclerosing cholangitis"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 52-year-old woman presents to her primary care physician because she has been feeling pain in her right leg. Specifically, she says that an area on her right thigh has been feeling tender and swollen over the past few weeks. Her past medical history is significant for obesity, poorly controlled diabetes, and hypertension. She also has been taking estrogen replacement therapy and drinking alcohol to cope with her symptoms of menopause. Her family history is significant for cardiomyopathy. On physical exam, there is erythema and edema along a cord-like lesion in her thigh. This lesion feels thick and hardened on palpation and is tender to the touch. She is started on compression therapy as well as NSAIDs for pain management. Which of the following characteristics of this patient most likely increased her risk for this disorder?", "answer": "Estrogen therapy", "options": {"A": "Alcohol use", "B": "Cardiomyopathy", "C": "Diabetes", "D": "Estrogen therapy", "E": "Hypertension"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 34-year-old woman presents to the clinic complaining of constipation and dry mouth. She had uncontrollable diarrhea for 1 day and took some medications afterwards. Patient denies any recent hospitalizations or antibiotic use. She also denies melena, hematochezia, nausea, or vomiting. Vitals are within normal limits. What medication did the patient take?", "answer": "Loperamide", "options": {"A": "Loperamide", "B": "Metronidazole", "C": "Oral vancomycin", "D": "Sulfasalazine", "E": "Setraline"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 25-year-old arrives at a gynecology clinic for a consult as she and her husband plan to conceive a baby soon. She is currently taking no medications, doesn’t smoke, and drinks alcohol socially. Her father passed away at the age of 51 due to heart failure. Her vital signs include blood pressure 150/100 mm Hg, heart rate 67/min, respiratory rate 16/min, and temperature 36.7°C (98.0°F). Physical examination is unremarkable. When asked about her high blood pressure, the patient says that her primary care physician once told her that her blood pressure was elevated on most of her visits; the physician emphasized that she should exercise and control her diet, but she never followed up with him as she always felt good. A number of tests are run to find out the etiology of her elevated blood pressure. Everything is within the normal range except for a renal angiogram shown in the picture. What is the most likely cause of this patient’s high blood pressure?", "answer": "Fibromuscular hyperplasia", "options": {"A": "Atherosclerosis", "B": "Adult polycystic kidney disease", "C": "Glomerulonephritis", "D": "Fibromuscular hyperplasia", "E": "Pheochromocytoma"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 73-year-old man is found to have an early stage hepatocellular carcinoma in the left lobe of his liver. He decides to undergo surgery to remove the tumor through partial liver resection. During the procedure, a ligament is found that attaches the liver to the anterior abdominal wall. Since part of this ligament lies over the part of the liver that needs to be resected, the ligament is incised to allow for removal of the tumor. The free edge of the ligament is found to have a thickening with small remnant blood vessels. Which of the following embryonic structures most likely gave rise to the thickening described here?", "answer": "Left umbilical vein", "options": {"A": "Ductus venosus", "B": "Left umbilical artery", "C": "Left umbilical vein", "D": "Right umbilical artery", "E": "Ductus arteriosus"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A researcher is conducting an experiment on the physiology of body fluids. He documents specific observations and plots some of them as a Darrow-Yannet diagram. In his study, some diagrams are normal, while most are abnormal. The abnormalities in the diagram are mostly in the form of changes in the x-axis, changes in the y-axis or changes in both axes of the diagram. Which of the following parameters are most likely to affect the x-axis in the diagram?\n ", "answer": "Fluid volume", "options": {"A": "Fluid density", "B": "Fluid osmolality", "C": "Fluid surface tension", "D": "Fluid viscosity", "E": "Fluid volume"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "An 11-year-old girl is brought to a pediatrician by her parents with recurrent wheezing for the last 3 years. After a detailed history, complete physical examination, and thorough diagnostic evaluation, the pediatrician informs the parents that the girl has mild persistent asthma, which will be most effectively treated with inhaled corticosteroids (ICS). However, her parents firmly object to the use of corticosteroids in any form, despite being told that the side effects associated with ICS are negligible. Therefore, the pediatrician suggests the regular use of a drug that does not contain a corticosteroid. The pediatrician mentions that the drug is used as prophylaxis only and will not be useful to treat acute bronchospasm. Which of the following drugs is most likely suggested by the pediatrician?", "answer": "Inhaled cromolyn sodium", "options": {"A": "Subcutaneous terbutaline", "B": "Inhaled ipratropium bromide", "C": "Oral theophylline", "D": "Inhaled cromolyn sodium", "E": "Oral roflumilast"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A team of scientists is researching the synthesis of a drug that would potentially reduce blood pressure in hypertensive patients by a novel mechanism of action. The drug A is an inactive prodrug and enters hepatocytes, reacts with reactant B, a native material in the cell, and creates products C and D. D has a blood pressure lowering effects. The reaction requires the presence of enzyme E. The researcher observes that, for the above chemical reaction, Gibbs free energy change (ΔG) is less than zero in normal hepatocytes whereas, in hepatocytes of patients with fatty liver, ΔG is more than 0 due to some unknown reason. Based on this knowledge, provided the concentration and actions of reactant B and enzyme E are same in both normal hepatocytes and hepatocytes of fatty liver patients, which of the following is the most likely possibility if drug A is administered to hypertensive patients with fatty liver?", "answer": "Drug A will not decrease blood pressure, regardless of its dose or supplementation of B or E", "options": {"A": "Drug A will decrease blood pressure only if reactant B is also supplemented in necessary dose", "B": "Drug A will decrease blood pressure only if enzyme E is also supplemented in necessary dose", "C": "Drug A will not decrease blood pressure, regardless of its dose or supplementation of B or E", "D": "Drug A will decrease blood pressure in same dose as required for patients with a healthy liver", "E": "Increased dose of drug A will be required to decrease blood pressure"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 70-year-old man comes to the physician because of a 4-month history of progressively worsening lower back pain. He describes the pain as a constant, dull ache that interferes with his sleep and is only partially relieved with ibuprofen. Two years ago, he was diagnosed with advanced prostate cancer, for which he underwent radiation therapy of the prostate and bilateral orchiectomy. One year postoperatively, serum prostate-specific antigen (PSA) was undetectable. He missed his previous follow-up visit. Current medications include over-the-counter ibuprofen. Vital signs are within normal limits. Physical examination shows tenderness of the spinous process of the third lumbar vertebra. Digital rectal examination shows a hard, nontender prostate. The remainder of the examination shows no abnormalities. The serum PSA concentration is 16 ng/mL (N<4). A technetium-99m bone scan shows increased uptake at the second and third lumbar vertebral bodies. In addition to analgesia, which of the following is the most appropriate next step in management?", "answer": "External beam radiotherapy to the lumbar vertebrae", "options": {"A": "External beam radiotherapy to the lumbar vertebrae", "B": "Leuprolide therapy", "C": "Finasteride therapy", "D": "Observation with no further treatment", "E": "Active surveillance\n\""}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 24-year-old woman presents complaining of a new onset vaginal odor. She reports that she is sexually active in a monogamous relationship with the same partner for two years. You perform a KOH prep, and notice an abnormal smell. On microscopy in your office, you observe the findings in figure A.\n\nWhat is the most likely causative organism?", "answer": "Gardnerella vaginalis", "options": {"A": "Trichomonas vaginalis", "B": "Candida albicans", "C": "Escherichia coli", "D": "Gardnerella vaginalis", "E": "Neisseria gonorrhoeae"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 22-year-old woman is brought to the emergency department 4 hours after the ingestion of 25 tablets of an unknown drug in an attempt to commit suicide. Her temperature is 36.7°C (98°F), pulse is 41/min, respirations are 14/min, and blood pressure is 88/55 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 93%. She is confused and oriented only to person. The pupils are equal and reactive to light. Examination shows cold, clammy extremities. Scattered expiratory wheezing and rhonchi are heard throughout both lung fields. The abdomen is soft. Fingerstick blood glucose concentration is 65 mg/dL. ECG shows prolonged PR intervals and narrow QRS complexes. Two large bore cannulas are inserted and intravenous normal saline, dextrose, and atropine are administered. Five minutes later, pulse is 51/min and blood pressure is 95/61 mm Hg. In addition to securing the airway, which of the following is the most appropriate next step in management?", "answer": "Glucagon", "options": {"A": "Glucagon", "B": "Activated charcoal", "C": "Sodium bicarbonate", "D": "Hemodialysis", "E": "Naloxone"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 56-year-old patient reports a history of recurrent dental caries. The bacteria causing this patient's dental problems most likely exhibits which of the following properties?", "answer": "Production of dextrans from glucose", "options": {"A": "Inhibition of growth on optochin sensitivity test", "B": "Gram negative diplococci", "C": "Production of dextrans from glucose", "D": "Presence of catalase enzyme", "E": "Soluble in bile"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 40-year-old woman comes to the physician for a follow-up examination. She says she has felt fatigued for about 3 months. She does not have enough energy for her job as a physician's assistant and often has to lie down and rest during shifts. She no longer adheres to her usual exercise routine because of exhaustion. During this time, she has noticed that her stools are sometimes pale and foul smelling. She also has generalized itching. The patient does not have abdominal pain, fever, or weight loss. She takes levothyroxine for hypothyroidism. She has smoked one pack of cigarettes weekly for 20 years. Physical examination shows no abnormalities. Laboratory studies show:\nHemoglobin 14.1 g/dL\nLeukocyte count 7,200/mm3\nErythrocyte sedimentation rate 26 mm/h\nSerum\nThyroid-stimulating hormone 4.2 μU/ml\nBilirubin\nTotal 1.7 mg/dL\nDirect 1.0 mg/dL\nAlkaline phosphatase 370 U/L\nAspartate aminotransferase 80 U/L\nAlanine aminotransferase 46 U/L\nCholesterol 320 mg/dL\nGamma-glutamyl transferase 98 U/L (N = 5–50)\nMagnetic resonance cholangiopancreatography shows no gallstones and no evidence of extrahepatic biliary obstruction. Liver biopsy shows nonsuppurative destructive cholangitis with lymphocytic infiltration of portal areas and periductal granulomas. Which of the following autoantibodies is most likely to be present in this patient?\"", "answer": "Anti-mitochondrial antibodies", "options": {"A": "Anti-liver-kidney microsomal-1 antibodies", "B": "Anti-mitochondrial antibodies", "C": "Anti-smooth muscle antibodies", "D": "Anti-endomysial antibodies", "E": "Perinuclear anti-neutrophil cytoplasmic antibodies"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 73-year-old man seeks evaluation for difficulty developing and maintaining erections. He has recently made lifestyle modifications, such as losing 4.5 kg (10 lb) but his erectile symptoms have not improved. He was prescribed a drug by his physician. Inhibition of which of the following best describes this drug’s mechanism of action?", "answer": "cGMP phosphodiesterase", "options": {"A": "5-alpha reductase", "B": "cAMP phosphodiesterase", "C": "cGMP phosphodiesterase", "D": "Estrogen receptors", "E": "Testosterone receptors"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 65-year-old woman with hypertension comes to the emergency department because of sudden onset of a severe headache 2 hours ago. Her temperature is 35°C (95°F) and blood pressure is 189/115 mm Hg. A CT scan of the head shows a subarachnoid hemorrhage and she is started on appropriate pharmacotherapy. Which of the following regions of the brain is most likely affected?", "answer": "Preoptic nucleus", "options": {"A": "Anterior cingulate gyrus", "B": "Ventral lateral thalamic nucleus", "C": "Pineal gland", "D": "Preoptic nucleus", "E": "Caudate nucleus"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 35-year-old woman with a one-year history of auditory hallucinations and periods of anhedonia and amotivation is being seen by her psychiatrist. She was started on haloperidol at her last visit, but she was told to stop taking the medication since she developed muscle stiffness and spasms soon after taking the drug. Today, her temperature is 97.7°F (36.5°C), blood pressure is 132/76 mmHg, pulse is 98/min, and respirations are 12/min. The patient is now started on a new medication that will seek to avoid the same side effects as her previous one; however, she will need to come in for weekly testing. Which of the following should be tested weekly?", "answer": "White blood cell count", "options": {"A": "Electrocardiogram", "B": "Electrolytes", "C": "Gonadotropin releasing hormone", "D": "Liver panel", "E": "White blood cell count"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 9-year-old boy is brought to the emergency room by his concerned mother after he \"urinated blood.\" The boy reports that, starting this morning, he experienced significant pain with urination and his urine appeared a bright red color. These symptoms were not present before today; however, he reports a cough, runny nose, and sore throat that started approximately 3 days ago. Vital signs are as follows: T 38.4 deg C, HR 101, BP 110/65, RR 14, SpO2 99%. Physical examination is significant for bilateral conjunctivitis, tenderness to suprapubic palpation, and a small amount of clotted blood is noted surrounding the urethral meatus. A urine sample is obtained, and urinalysis shows 3+ blood, and urine microscopy demonstrates gross blood with too many cells to count per high powered field. Which of the following is the most common viral cause of this child's condition?", "answer": "Adenovirus", "options": {"A": "Parvovirus B19", "B": "Coronavirus", "C": "Echovirus", "D": "Adenovirus", "E": "Coxsackie A virus"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A young researcher wants to develop a method of increasing oxygen delivery to the peripheral tissues. He brainstorms several ideas but is informed by his mentor that only one of his ideas will most likely help him achieve the desired result. Of the following proposed mechanisms, which one would best serve the researcher's purpose?", "answer": "Increase taut form hemoglobin in muscle capillaries", "options": {"A": "Decrease lactic acid production by skeletal muscle", "B": "Increase fetal hemoglobin concentration in circulation", "C": "Increase relaxed form hemoglobin in muscle capillaries", "D": "Increase taut form hemoglobin in muscle capillaries", "E": "Shift intracellular hemoglobin into plasma"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 29-year-old man comes to the physician for a follow-up examination. He has had numbness and tingling of his legs for the past 10 days. Three months ago, he was diagnosed with pulmonary tuberculosis and started on antituberculosis therapy. Examination shows dry scaly lips and cracks at the corner of the mouth. Sensation to pinprick and light touch is decreased over the lower extremities. His hemoglobin concentration is 10.4 g/dL and mean corpuscular volume is 76 μm3. Administration of which of the following is most likely to have prevented this patient's current symptoms?", "answer": "Pyridoxine", "options": {"A": "Iron", "B": "Vitamin E", "C": "Folic acid", "D": "Vitamin B12", "E": "Pyridoxine"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 36-year-old woman presents with a 2-month history of urinary incontinence, accompanied by urgency, nocturia, and occasional hematuria. Her symptoms are present day and night and have no known triggers. She was diagnosed with grade 2 pelvic organ prolapse (cystocele) 1 year ago, which is managed with pelvic floor training exercises and a vaginal pessary. She is otherwise healthy and does not take any medications. The blood pressure is 120/80 mm Hg, the heart rate is 67/min, the respiratory rate is 14/min, and the temperature is 36.8℃ (98.2℉). The physical examination is significant for suprapubic tenderness. No costovertebral angle tenderness is present. There are no signs of vulvar inflammation, and no urethral or vaginal discharge. The vaginal mucosa is normal and there is no cervical discharge. A vaginal pessary is placed. The cervix is non-tender and mobile, the uterus is not enlarged, and the adnexa have no masses.\nThe urinalysis shows the following findings:\n Color:  Pale yellow\n Clarity:  Clear\n pH:  6.2\n Specific gravity:  1.023\n Glucose:  Negative\n Ketones:  Negative\n Nitrites:  Positive\n Leukocyte esterase:  Positive\n Bilirubin:  Negative\n Urinary bilirubin:  Negative\n Protein: Negative\n RBCs:  47 RBCs/hpf\n WBCs:  21 WBCs/hpf\n Epithelial cells:  27 squamous epithelial cells/hpf\n Casts:  5 hyaline casts/lpf\n Crystals:  Occasional urates\n Bacteria:  None noted\n Yeast:  None noted\nThe urinary culture is negative. Which investigation should be performed next in this patient?", "answer": "Ultrasound examination", "options": {"A": "Cystoscopy", "B": "Ultrasound examination", "C": "Cystometry", "D": "Cystography", "E": "Pelvic CT scan"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "The incidence of red-green color blindness in males in a certain population is 1/100. Which of the following is closest to the probability of a female and a male with normal vision having a daughter with red-green color blindness?", "answer": "0", "options": {"A": "1/100", "B": "99/100", "C": "1/50", "D": "98/100", "E": "0"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 31-year-old man comes to the physician for evaluation of chronic cough, sinus pain, and nasal discharge. He has a history of frequent upper respiratory infections and recurrent sinusitis since childhood. He is also concerned about fertility, as he and his wife have been trying to conceive for 5 years unsuccessfully. Pulmonary examination shows crackles and wheezing throughout both lung fields. A CT scan of the chest is shown. The most likely cause of this patient's condition is a defect in which of the following molecular structures?", "answer": "Dynein arm", "options": {"A": "IL-2R gamma chain", "B": "NADPH oxidase", "C": "CFTR protein", "D": "Dynein arm", "E": "α-1 antitrypsin"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 3-year-old boy is brought to the emergency department because of abdominal pain and watery diarrhea for the past 3 days. This morning he also had nausea and his stool had a red tint. Four days ago, he and his parents returned home from a vacation, during which they visited a petting zoo and consumed many new foods. He lives with his family and they have cats and dogs at home. The patient attends daycare. His immunizations are up-to-date. His temperature is 38°C (100.4°F), pulse is 140/min, and blood pressure is 80/45 mm Hg. Examination shows dry mucus membranes. The abdomen is soft, and there is tenderness to palpation of the right lower quadrant with rebound. Stool culture grows Yersinia enterocolitica. Which of the following is most likely to have prevented this patient's condition?", "answer": "Avoiding the consumption of undercooked pork", "options": {"A": "Hand-washing at daycare", "B": "Avoiding the consumption of undercooked pork", "C": "Avoiding the consumption of deli meats", "D": "Avoiding the consumption of unwashed vegetables", "E": "Avoiding the consumption of home-canned food"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 61-year-old woman dies unexpectedly. She had not seen a physician in 10 years. Examination of the heart during autopsy shows hypertrophy of the left ventricular wall and enlargement of the left ventricular chamber. Microscopic examination shows lengthening of individual muscle fibers due to duplication of sarcomeres in series. Which of the following is the most likely underlying cause of these findings?", "answer": "Increased left ventricular end diastolic volume", "options": {"A": "Increased pulmonary arterial pressure", "B": "Decreased left ventricular contractility", "C": "Decreased left ventricular compliance", "D": "Increased systemic vascular resistance", "E": "Increased left ventricular end diastolic volume"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 57-year-old man with a history of hypertension, hyperlipidemia, type 2 diabetes mellitus, and obstructive sleep apnea presents to your office for routine screening. He reports compliance with his medications but admits to difficulty maintaining the diet and exercise routines discussed during his last visit. He does not have any other complaints. He drinks 3-4 beers on the weekends and does not smoke cigarettes. His current medications include metformin, atorvastatin, and hydrochlorothiazide. On physical examination, his temperature is 99°F (37.2°C), blood pressure is 130/85 mmHg, pulse is 85/min, and respirations are 18/min. Laboratory results are shown below:\n\nSerum:\nNa+: 138 mEq/L\nCl-: 100 mEq/L\nK+: 3.9 mEq/L\nHCO3-: 23 mEq/L\nBUN: 13 mg/dL\nGlucose: 160 mg/dL\n\nYou decide to start the patient on a medication that triggers insulin release. What is the mechanism of action of this drug?", "answer": "Close potassium channels", "options": {"A": "Close potassium channels", "B": "Increase insulin sensitivity", "C": "Inhibit intestinal brush border enzymes", "D": "Delay gastric emptying", "E": "Increase ATP generation"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 28-year-old woman presents to the emergency department with fever and abdominal pain for the past several days. She says she feels like she has a slight fever. She denies nausea or vomiting. Physical examination shows pain in the right upper quadrant to deep palpation with rebound tenderness and guarding. A laparoscopy is performed which shows string-like, fibrous scar tissue in the perihepatic recesses. Which of the following is the most likely organism responsible for the patient's condition?", "answer": "Neisseria gonorrhoeae", "options": {"A": "Giardia lamblia", "B": "Gardnerella vaginalis", "C": "Trichomonas vaginalis", "D": "Treponema pallidum", "E": "Neisseria gonorrhoeae"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 30-year-old woman comes to the emergency department because of a 1-day history of sharp chest pain radiating to the left shoulder. The pain worsens when she coughs, breathes deeply, or lies down. She has had a mild fever and a cough for the past 2 days. She takes ibuprofen for hip and knee pain, which started 4 months ago. Examination shows a symmetric, erythematous rash on her nose and cheeks, and erythematous patches with scaling and plugged follicles over her hands. Cardiovascular evaluation of this patient is most likely to show which of the following findings?", "answer": "Triphasic scratchy heart sound of varying intensity", "options": {"A": "Increased distension of jugular veins during inspiration", "B": "18 mm Hg decrease in systolic blood pressure during inspiration", "C": "High-pitched pericardial sound occurring slightly earlier than a third heart sound", "D": "Triphasic scratchy heart sound of varying intensity", "E": "Holosystolic blowing murmur heard best at the apex"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 22-year-old man comes to the physician because he has been increasingly worried and stressed in recent weeks. He started a marketing job three months ago, which involves traveling between Washington and California several times a year. Two months ago, he was supposed to fly to Seattle, but he experienced nausea, palpitations, sweating, and shortness of breath and was unable to board the plane, causing him great embarrassment. He had never been on a plane before; his parents died in a plane crash when he was younger. A week ago, he called in sick when he was supposed to go on a business trip. He worries that he will lose his job. He is otherwise well and has no history of serious illness. He takes no medications. His temperature is 37.2°C (99°F), pulse is 85/min, respirations are 12/min, and blood pressure is 130/80 mm Hg. Physical examination shows no abnormalities. On mental status examination, he is alert and cooperative. His speech is normal and his thought process is organized. His memory, attention, and concentration are intact. Which of the following is the most appropriate next step in management of this patient's symptoms?", "answer": "Cognitive behavioral therapy", "options": {"A": "Oral paroxetine", "B": "Oral alprazolam", "C": "Oral propranolol", "D": "Observation", "E": "Cognitive behavioral therapy"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 52-year-old man presents to the office complaining of a 2-week history of fatigue, progressively worsening shortness of breath, and swelling of his lower legs and feet. His past medical history is only significant for slightly elevated blood pressure. The patient denies tobacco use although he does admit to drinking 8-10 beers, daily, for the past 10 years. He takes a low dose of aspirin daily, ever since he had an anterior myocardial infarction 2 years ago. The patient works as a financial consultant and frequently travels for work. The current temperature is 36.8°C (98.3°F), the pulse rate is 68/min, the blood pressure is 152/84 mm Hg, and the respiratory rate is 16/min. His weight is 102 kg (224 lb) and height 180 cm (5 ft 9 in). Echocardiography demonstrates an ejection fraction of 35% and a thin left ventricular wall. What is the appropriate medication for this patient’s condition?", "answer": "Spironolactone", "options": {"A": "Nifedipine", "B": "Atorvastatin", "C": "Procainamide", "D": "Ibuprofen", "E": "Spironolactone"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 70-year-old man comes to the physician for a follow-up evaluation. Eight months ago, he presented with a 6-month history of increased urinary frequency, difficulty to initiate urination, and straining to maintain the urinary stream. Digital rectal examination showed symmetrically enlarged, nontender prostate with rubbery texture. Laboratory studies showed a prostate-specific antigen (PSA) level of 2 ng/mL. Abdominal ultrasound showed a post-void residual urine volume of 250 ml and bladder wall thickening. The patient received appropriate treatment. His vital signs are within normal limits. Laboratory studies now show a PSA level of 1 ng/mL. Which of the following medications was most likely used to treat this patient's symptoms?", "answer": "Dutasteride", "options": {"A": "Oxybutynin", "B": "Dutasteride", "C": "Terazosin", "D": "Flutamide", "E": "Tadalafil"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 53-year-old man presents to the office complaining of persistent abdominal pain. He states that he has gained 4.5 kg (10.0 lb) because the pain is only relieved by eating. The patient also admits that he has had numerous loose, foul-smelling stools over the last few weeks with associated nausea. He has taken some over the counter antacids without relief or change in symptoms. His blood pressure is 132/76 mm Hg, respiratory rate is 14/min, and heart rate is 75/min. Physical examination reveals mild tenderness to palpation of the upper abdomen. Which of the following is the most likely diagnosis?", "answer": "Zollinger-Ellison syndrome", "options": {"A": "Whipple disease", "B": "H. pylori infection", "C": "Intestinal type gastric adenocarcinoma", "D": "NSAID induced peptic ulcer disease", "E": "Zollinger-Ellison syndrome"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 68-year-old man with advanced dementia is brought to the preoperative unit prior to an elective cholecystectomy for biliary colic. He says he does not want the surgery anymore. He begins yelling at unit staff and requests to leave. His designated medical power of attorney, who had previously signed the surgery consent forms, is present. Which of the following is the most appropriate next step in management?", "answer": "Ask the patient about his concerns and try to address them", "options": {"A": "Consult psychiatry for capacity evaluation", "B": "Cancel the surgery and allow the patient to leave", "C": "Ask the patient about his concerns and try to address them", "D": "Call family members and schedule a family meeting", "E": "Perform cognitive screening evaluation"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 67-year-old man presents to his physician’s office with a progressive cough. It has been increasing in intensity over the past week. He has also been noticing an increase in the amount of sputum he usually produces, which is thick and yellow. He also complains of increased difficulty in breathing, more so than he previously experienced. He was diagnosed with chronic obstructive lung disease (COPD) about 3 years ago and has been on treatment for it since then. He doesn’t report any fever, chills, or night sweats. He has observed a foul smell to his sputum. His blood pressure is 100/65 mm Hg, the respirations are 23/min and the pulse is about 110/min. Currently, his FEV1 is around 48% of the normal predicted value. He is currently receiving a yearly influenza shot and has taken the pneumococcal vaccination at the time of his diagnosis. In spite of this, he has had acute exacerbations of his symptoms 4 times over the last year. His last episode was 2 months ago, for which he was treated with a short course of antibiotics. He is also currently receiving treatment for diabetes. Which of the following pathogens should be considered before initiating treatment for the current episode?", "answer": "P. aeruginosa", "options": {"A": "S. pneumonia", "B": "H. influenzae", "C": "P. aeruginosa", "D": "M. catarrhalis", "E": "Syncytial virus"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 27-year-old man who was involved in a motor vehicle collision is brought into the emergency room with a fractured skull. The paramedics report that the patient was conscious and lucid on the way to the hospital but now is unresponsive. His vitals are a blood pressure of 122/78 mm Hg, temperature of 37.0°C (98.6°F), pulse rate of 88/min, and respiratory rate of 14/min. A noncontrast CT scan of the head shows an epidural hematoma. Which of the following structures is involved in the development of an epidural hematoma?", "answer": "Middle meningeal artery", "options": {"A": "Middle meningeal artery", "B": "Bridging cortical veins", "C": "Arteriovenous malformation", "D": "Saccular aneurysm", "E": "Lenticulostriate vessels"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 54-year-old woman presents to the emergency department due to recent onset of a high fever, accompanied by severe headache and neck stiffness. Her past medical history is significant for rapidly progressive glomerulonephritis. She is currently on immunosuppressants after a kidney transplant performed 6 months ago. On presentation, her temperature is 102.2°F (39°C), blood pressure is 112/71 mmHg, pulse is 107/min, and respirations are 22/min. Physical exam reveals severe pain with neck flexion and reciprocal knee flexion. Laboratory tests reveal a gram-positive organism with endotoxin. Which of the following characteristics is true of the most likely cause of this patient's disorder?", "answer": "Tumbling motility in broth", "options": {"A": "Anaerobic spore forming rods", "B": "Catalase-negative", "C": "Coagulase-positive", "D": "Tumbling motility in broth", "E": "V formation of club-shaped rods"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 2-year-old boy is brought to see the pediatrician by his mother due to a “bad” cough. The mother reports that he has been coughing so hard that he threw up on several occasions. He is adopted and the mother does not know his vaccination history. He has no known allergies. His temperature is 38.5°C (100.5°F), pulse is 120/min, respirations are 33/min, blood pressure is 101/54 mm Hg, and oxygen saturation is 96% on room air. The boy looks unwell with mild difficulty breathing and a nonproductive cough multiple times followed by a “whoop” sound during the inhalation. He has scattered petechiae on his face. A nasopharyngeal swab is sent for culture and PCR. Which of the following antibiotics is recommended for this patient?", "answer": "Erythromycin", "options": {"A": "Ciprofloxacin", "B": "Ceftriaxone", "C": "Cefotaxime", "D": "Erythromycin", "E": "Ampicillin"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 19-year-old man returns from travel in South America. He presents complaining of profuse, watery diarrhea. You suspect the causative organism to be Enterotoxigenic E. coli. What is the mechanism by which this organism causes diarrhea?", "answer": "Stimulates adenylate cyclase (increasing cAMP)", "options": {"A": "Blocks the release of inhibitory neurotransmitters GABA and glycine", "B": "Blocks the presynaptic release of acetylcholine at the neuromuscular junction", "C": "Inactivates mammalian 60S ribosomal subunit", "D": "Stimulates release of cytokines", "E": "Stimulates adenylate cyclase (increasing cAMP)"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 38-year-old man presents to the clinic for complaints of abdominal pain and diarrhea. He reports a long-standing history of the symptoms except for the time when he attempted a carbohydrate-free diet 5 years ago. The pain is described as stabbing, diffuse, 8/10, and is especially worse following food intake. Recently, he noticed some numbness and tingling of his feet but denies any bloody stool, nausea, vomiting, fevers, weight loss, or focal neurological deficits. What histopathological findings would you expect to find in this patient?", "answer": "Blunting of the intestinal villi at the ileum", "options": {"A": "Blunting of the intestinal villi at the ileum", "B": "Crypt abscesses at the descending colon", "C": "Noncaseating granulomas at the ileum", "D": "Normal gastric mucosa at the jejunum", "E": "PAS-positive foamy macrophages at the jejunum"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 25-year-old male presents for a new primary-care visit. He has never been seen by a physician and reports that he has been in good health. You note a very tall, very thin male whose arm span is greater than his height. The patient reports that his father had a similar build but passed away suddenly in his 40s. You suspect a genetic disorder characterized by a defect in fibrillin-1. What is the histopathology of the most common large-artery complication of this disease?", "answer": "Cystic medial degeneration", "options": {"A": "Focal granulomatous inflammation with mural lymphocytes, macrophages, giant cells", "B": "Eosinophilic vasculitis", "C": "Predominant neutrophilic infiltration with fibrinoid necrosis", "D": "Fibrinoid necrosis of blood vessel walls, endothelial swelling, and neutrophilic infiltrate in skin lesions", "E": "Cystic medial degeneration"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A group of investigators is evaluating the efficacy of intranasal ketamine in decreasing acute suicidality in teenagers admitted to inpatient psychiatric units. They conducted a pilot study in which 15 participants were randomized to receive intranasal ketamine while 15 participants were randomized to receive placebo. The investigators ultimately found no statistically significant difference in suicidality after 30 days of follow up with the level of significance fixed at 5%. They suspect inadequate statistical power. Assuming the investigators intend to keep the level of significance at 5%, which of the following changes would be most effective to increase the statistical power?", "answer": "Decrease the type II error rate", "options": {"A": "Decrease alpha", "B": "Decrease the sample size", "C": "Decrease the type II error rate", "D": "Increase beta", "E": "Increase the type I error rate"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 56-year-old man presents with severe back pain for the past hour. He says the pain started about 1 hour ago and has not improved. The patient describes the pain as sharp, 10/10, and located between his scapula. Past medical history is significant for hypertension, which he is noncompliant with medication. His vital signs are a blood pressure of 180/95 mm Hg and a pulse of 108/min. On physical examination, there is a loss of pain and temperature sensation in the lower trunk and extremities bilaterally. Strength is 4 out of 5 in all muscle groups in the lower extremities bilaterally. A contrast CT of the chest reveals findings consistent with a type B aortic dissection. Which of the following etiologies is the most likely cause of this patient’s neurologic findings?", "answer": "Anterior cord syndrome", "options": {"A": "Central cord syndrome", "B": "Brown-Séquard syndrome", "C": "Spinal cord compression", "D": "Anterior cord syndrome", "E": "Spinal epidural hematoma"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 7-year-old girl is brought to the physician by her mother because of a 6-month history of worsening fatigue and frequent upper respiratory tract infections. She is at the 2nd percentile for height and 10th percentile for weight. Physical examination shows pallor, diffuse hyperpigmented macules, absence of the radial bones, and hypoplastic thumbs. Her hemoglobin concentration of 8.7 g/dL, leukocyte count is 2,500/mm3, and platelet count is 30,000/mm3. This patient's condition is most likely caused by a defect in a gene encoding a protein that is normally involved in which of the following processes?", "answer": "DNA interstrand crosslink repair", "options": {"A": "Excision of pyrimidine dimers", "B": "Hydrolysis of glucocerebroside", "C": "DNA interstrand crosslink repair", "D": "Maturation of erythroid progenitor cells", "E": "Ras signal transduction pathway"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 36-year-old woman is brought to the emergency department because of loss of consciousness. Her husband says that she complained of vomiting and dizziness for 2 days, but did not seek medical care. She has a history of acral vitiligo. Her blood pressure is 90/60 mm Hg, temperature is 35.9°C (96.6°F), and pulse is 90/min. On physical examination, she is obtunded, skin turgor is reduced, and her oral mucosa is dry with hyperpigmented spots on the inner side of both cheeks. Lab results are shown:\nRandom plasma glucose 40 mg/dL\nSerum osmolarity 275 mOsm/kg H₂O\nSerum sodium 130 mEq/L\nSerum potassium 6 mEq/L\nUrine sodium level 30 mEq/L\nECG shows normal sinus rhythm without ST-T wave changes. Dextrose 5% is given and random plasma glucose becomes 60 mg/dL, but her blood pressure is still the same. Which of the following is the best next step in the management of this patient condition?", "answer": "Normal saline and intravenous dexamethasone", "options": {"A": "Intravenous calcium gluconate", "B": "ACTH stimulation test", "C": "Subcutaneous octreotide", "D": "Oral dehydroepiandrosterone (DHEA)", "E": "Normal saline and intravenous dexamethasone"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 4-year-old girl is seen by her pediatrician for developmental delay. One year prior, the patient was able to ride a tricycle, stack 3 blocks, and speak in short sentences. Now, she is unable to feed herself and has recently started to point to objects she wants rather than asking. Physical exam reveals a well nourished child sitting in a stroller wringing her hands. Vital signs are normal. The patient's mother reports that her 7-year-old son is doing well, and that they have no family history of mental retardation or other cognitive disorders. What is the most likely diagnosis?", "answer": "Rett syndrome", "options": {"A": "Angelman syndrome", "B": "Rett syndrome", "C": "Beckwith–Wiedemann syndrome", "D": "Prader-Willi syndrome", "E": "McCune-Albright syndrome"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 49-year-old woman visits the emergency department with the acute onset of severe shortness of breath. She also reports right-sided calf pain that developed after a 22-hour flight from Beijing to Los Angeles, and that, several hours after she felt pain in her calf, she began to have trouble breathing. Currently, her shortness of breath is so severe that she is unable to speak clearly or quickly, but she manages to deny any recent surgery or history of recent bleeding. The vital signs include: blood pressure 111/69 mm Hg, pulse 142/min, and respiratory rate 33/min. On observation, she is using accessory muscles to breathe. On auscultation, her lungs are clear and her heart rate is rapid but regular. Her right calf is swollen, warm, and tender. The arterial blood gas test result reveals a pH of 7.5, partial pressure of carbon dioxide (PCO2) 22 mm Hg, and a partial pressure of oxygen (PaO2) 47 mm Hg on 6 L of oxygen by nasal cannula. Which of the following is the most appropriate next step in the management of this patient?", "answer": "Streptokinase", "options": {"A": "Unfractionated heparin", "B": "Streptokinase", "C": "Low molecular-weight heparin", "D": "Warfarin", "E": "Embolectomy"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 37-year-old woman, gravida 4, para 3, at 35 weeks' gestation is admitted to the hospital in active labor. She has had no prenatal care. Her three children were delivered by lower segment transverse cesarean section. The patient appears in acute distress. Her pulse is 98/min, respirations are 15/min, and blood pressure is 130/80 mm Hg. The abdomen is nontender and contractions are felt. The fetus is in a cephalic presentation. The fetal heart rate is reactive with no decelerations. One hour following vaginal delivery, the placenta is not delivered. Manual separation of the placenta leads to profuse vaginal bleeding. A firm, nontender uterine fundus is palpated at the level of the umbilicus. Which of the following is the most likely diagnosis?", "answer": "Placenta accreta", "options": {"A": "Ruptured vasa previa", "B": "Uterine rupture", "C": "Placenta previa", "D": "Placenta accreta", "E": "Abruptio placentae\n\""}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 40-year-old man is brought to the clinic by his wife with a complaint of behavioral changes for the past few months. He is irritable and gets angry with trivial matters. He sometimes screams in the middle of the night and remains restless. His wife has recently noticed that he is forgetting things and repeats the same question multiple times. For the past few weeks, he is also having abnormal movements of his body, more prominent in the arms and hands. The past medical history is unremarkable. His father died at the age of 28 years old in a road traffic accident. His grandmother had similar symptoms after her retirement. He does not smoke, drinks alcohol, or uses illicit drugs. The physical examination reveals a restless ill-groomed man. He is having intermittent involuntary dance-like movements. The slit-lamp ophthalmic examination is normal. His mini-mental state examination (MMSE) score is 22/30. The complete blood count, basic metabolic profile, thyroid profile, liver profile, serum vitamin B12, and ceruloplasmin levels are within normal range. An MRI of the brain will reveal an atrophy of which of the following structure?", "answer": "Caudate nucleus", "options": {"A": "Caudate nucleus", "B": "Cerebellum", "C": "Diffuse cortex", "D": "Frontal and temporal lobes", "E": "Substantia nigra"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A researcher is studying the association between hemoglobin levels and BMI. He divides volunteers who wish to participate into 2 groups based on their BMI, a normal weight group and an overweight group. He then measures the hemoglobin level of all of the volunteers. His null hypothesis is that there is no association between hemoglobin levels and body weight. The mean hemoglobin level for the normal weight group is 13.4 g/dL and 13.8 g/dL for the overweight group. He obtains a mean difference of 0.4 g/dL between the 2 groups. He does an unpaired t-test and gets a p-value of 0.10. Which of the following statements best describes the study?", "answer": "If the null hypothesis is true, there is a 10% probability to get this difference of 0.4 g/dL or higher due to chance.", "options": {"A": "If the null hypothesis is not true, 10% or more of the volunteers would not show any association between hemoglobin level and weight.", "B": "If the null hypothesis is not true, there is still a 10% probability to not get this difference of 0.4 g/dL or higher due to chance.", "C": "If the null hypothesis is true, there is still a 10% probability of not getting this difference of 0.4 g/dL or higher due to chance.", "D": "If the null hypothesis is true, there is a 10% probability to get this difference of 0.4 g/dL due to chance.", "E": "If the null hypothesis is true, there is a 10% probability to get this difference of 0.4 g/dL or higher due to chance."}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 51-year-old female with a history of papillary thyroid carcinoma who is two weeks status-post thyroidectomy presents to her surgeon complaining of difficulty with her voice. Following the operation, she developed immediate hoarseness and difficulty speaking. The hoarseness has not improved since the operation. Her past medical history is notable for hypertension and obesity. Her temperature is 99°F (37.2°C), blood pressure is 120/80 mmHg, pulse is 90/min, and respirations are 16/min. Physical examination reveals a healing surgical scar without evidence of infection or dehiscence. Which of the following embryologic structures most likely gave rise to the structure that was damaged in this patient?", "answer": "Sixth branchial arch", "options": {"A": "First branchial arch", "B": "Second branchial arch", "C": "Third branchial arch", "D": "Fourth branchial arch", "E": "Sixth branchial arch"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "Six days after admission to the hospital for treatment of infective endocarditis, a 64-year-old woman develops persistent ringing in both ears, lightheadedness, and nausea. When she turns her head, she sees the light on the ceiling swinging from side to side. She has congestive heart disease, hypertension, and coronary artery disease. She was treated for a cerebrovascular accident 7 years ago and has no residual deficits. Current medications include intravenous vancomycin and gentamicin, as well as oral aspirin, atenolol, furosemide, and lisinopril. Her vital signs are within normal limits. Cardiac examination shows a grade 3/6 holosystolic murmur along the left lower sternal border. While the patient fixates on a target, administration of brisk, horizontal head rotations to both sides results in corrective saccades to refixate back to the target. She has an unsteady gait. Muscle strength and sensation are normal. Which of the following is the most likely cause of this patient's current symptoms?", "answer": "Medication toxicity", "options": {"A": "Decreased endolymph resorption", "B": "Dislodged otoliths", "C": "Suppurative labyrinthitis", "D": "Medication toxicity", "E": "Delirium"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A patient with congestive heart failure with viral myocarditis due to coxsackievirus infection presents to a local hospital for treatment and then returns home. Which of the following cardiac conditions are the most likely long-term consequence of the patient’s clinical presentation and hospitalization?", "answer": "Dilated cardiomyopathy", "options": {"A": "Concentric hypertrophy", "B": "Dilated cardiomyopathy", "C": "Endarteritis obliterans", "D": "Hypertrophic cardiomyopathy", "E": "Restrictive cardiomyopathy"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 5-year-old male presents to the pediatrician with his mother for a well child visit. His mother has no complaints. The patient is doing well in preschool and appears to be ready for kindergarten. He can begin to sound out letters and write out his first name. He has many friends at school and enjoys playing with his older siblings. The patient’s past medical history is notable for birth weight in the 99th percentile and unexplained hypoglycemia in the first week of life. The patient’s mother denies any family history of genetic syndromes or malignancy. The patient’s height and weight are in the 99th percentile. On physical exam, the patient has an enlarged tongue with no other dysmorphic features. He also has the physical exam findings seen in Figures A and B. This patient should be screened for abnormalities in which of the following organs?", "answer": "Kidneys", "options": {"A": "Adrenal glands", "B": "Bone", "C": "Eyes", "D": "Kidneys", "E": "Thyroid gland"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A first-year medical student undergoes a surgical procedure involving a midline laporotomy incision. The patient presents back to the surgeon approximately 3 months later and asks the surgeon: \"What type of tissue is causing the scar to form on my abdomen?\" The physician promptly answers:", "answer": "Type 1 collagen", "options": {"A": "Keratin", "B": "Type 1 collagen", "C": "Type 2 collagen", "D": "Type 3 collagen", "E": "Type 4 collagen"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 40-year-old female complains of muscle weakness. Her blood pressure is 180/140 mm Hg, and serum potassium is 3.2 mEq/L. Plasma renin levels are abnormally low. A CT scan of her abdomen reveals a 3 cm lesion in her right adrenal gland. The patient’s lesion is likely composed of functional cells from which of the following regions:", "answer": "Zona glomerulosa", "options": {"A": "Zona glomerulosa", "B": "Zona fasciculata", "C": "Zona reticularis", "D": "Adrenal medulla", "E": "Posterior pituitary"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 75-year-old woman is brought to the physician by her daughter because of a 1-month history of fatigue and a 3.5-kg (7-lb) weight loss. The patient has a history of hypertension, hyperlipidemia, and Alzheimer's dementia. She lives with her daughter and requires assistance with all of her banking and meal preparation. Her daughter has hypothyroidism but there is no other history of serious illness in the family. She does not remember the names of her medications but says she takes them every day. Her pulse is 114/min and blood pressure is 148/101 mm Hg. Physical examination shows warm skin and a tremor. The thyroid gland is not palpable. The serum thyroid stimulating hormone level is undetectable. Histological examination of a thyroid biopsy shows follicular atrophy. Which of the following is the most likely underlying cause of this patient's symptoms?", "answer": "Exogenous levothyroxine use", "options": {"A": "Graves disease", "B": "Exogenous levothyroxine use", "C": "Granulomatous thyroiditis", "D": "Iodine exposure", "E": "Medullary thyroid cancer\n\""}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 42-year-old man is brought to the emergency department by EMS from the scene of an automobile accident, where he appeared to be an unrestrained passenger. The patient is confused and unable to answer questions. His temperature is 98.6°F (37°C), pulse is 120/min, blood pressure is 75/44 mmHg, and respiratory rate is 22/min. On physical exam, there is bruising over his sternum and left chest, with tenderness to palpation. Cardiac auscultation reveals normal heart sounds with no murmurs, rubs, or gallops. He has marked jugular venous distention and bibasilar crackles on pulmonary auscultation with equal air entry bilaterally. Abdominal and cranial nerve exams are within normal limits. His extremities are cool with prolonged capillary refill, and he is diaphoretic. The patient is admitted to the intensive care unit and hemodynamic monitoring is established, which reveals a pulmonary capillary wedge pressure (PCWP) of 22 mmHg (normal range 8-12 mmHg), central venous pressure (CVP) of 12 cmH2O (normal range 4-12 cmH2O), cardiac output (CO) of 2.2 L/min (normal range 4-8 L/min), and systemic vascular resistance (SVR) of 1800 dynes/seconds/cm^-5 (normal range 700–1600 dynes/seconds/cm^-5). Which of the following types of shock best describes this patient's condition?", "answer": "Cardiogenic", "options": {"A": "Hypovolemic", "B": "Cardiogenic", "C": "Anaphylactic", "D": "Neurogenic", "E": "Obstructive"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 23-year-old man comes to the emergency department complaining of 10/10 abdominal pain. He describes the pain as sharp, stabbing, intermittent, and concentrated at the left lower quadrant. It started about 3 hours ago with no obvious precipitating factor. He reports multiple similar episodes in the past but they have all resolved within 1 hour or so. He denies fever, weight changes, headaches, nausea/vomiting, or gastrointestinal changes but endorses “red-colored urine” for the past day. He just returned from an extensive hiking trip in Colorado. A radiograph of the abdomen was unremarkable. What is the most likely explanation for this patient’s presentation?", "answer": "Hereditary defect of amino acid transporter in the kidney", "options": {"A": "Dehydration leading to a build up of uric acid in the urine", "B": "Hereditary defect of amino acid transporter in the kidney", "C": "Infection with urease positive bacteria", "D": "Presence of antibodies to the glomerular basement membrane", "E": "Thinning and splitting of the glomerular basement membrane"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 33-year-old African American woman presents to the emergency department due to diffuse pain and fatigue. The woman states that she feels like her bones and muscles diffusely hurt. She also has experienced some abdominal pain as well and states that she has trouble focusing. The patient has a past medical history of sickle cell disease for which she takes hydroxyurea. Her temperature is 98.1°F (36.7°C), blood pressure is 119/59 mmHg, pulse is 130/min, respirations are 16/min, and oxygen saturation is 98% on room air. Laboratory values are ordered and are currently pending. Which of the following is a side-effect of definitive treatment for this patient?", "answer": "Tetany", "options": {"A": "Dilute urine", "B": "Hyperglycemia", "C": "Peaked T-waves on ECG", "D": "QT shortening on ECG", "E": "Tetany"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 40-year-old man with psoriatic arthritis comes to the physician because of progressively worsening pain and stiffness in both of his hands and feet for the past 3 weeks. His psoriatic arthritis had been well-controlled with adalimumab for several years prior to this. His only other medication is omeprazole. Physical examination shows scaly plaques on both elbows and limited range of motion of most of the larger joints. Which of the following is the most likely underlying mechanism of the recurrence of this patient's symptoms?", "answer": "Formation of antidrug antibodies", "options": {"A": "Suppression of the bone marrow", "B": "Decreased ionization by the glomeruli", "C": "Formation of antidrug antibodies", "D": "Increased acetylation by the liver", "E": "Inhibition of cytochrome P450 activity"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 35-year-old African American female presents to the emergency department with a three day history of cough, chest pain, and fever. Upon presenting to the emergency department, her temperature is 101.4 °F (38.5 °C), blood pressure is 110/80 mmHg, pulse is 95/min, and respirations are 24/min. Lung auscultation reveals crackles over the left lung base. Chest radiograph reveals a dense consolidation in the left lower lung. The patient undergoes lab tests in the emergency department that demonstrate an elevated level of C-reactive protein. This abnormal lab finding was most likely caused by increased activity of which of the following mediators?", "answer": "IL-6", "options": {"A": "TNF-alpha", "B": "IL-12", "C": "IL-8", "D": "IL-6", "E": "IL-2"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 50-year-old man comes to the physician after a fall on a flight of stairs earlier that day. He slipped, causing him to fall and hit the handrail with the lateral part of his chest. He has no shortness of breath. He returned from a 10-day trip to South Africa 4 weeks ago. He smoked one pack of cigarettes daily for 10 years but stopped 18 years ago. He drinks 1–2 beers a week. His temperature is 37.1°C (98.8°F), pulse is 78/min, and blood pressure is 126/72 mm Hg. Examination shows normal breath sounds bilaterally. The left lateral chest wall is tender to palpation. An x-ray of the chest shows no fracture; there is a 5-mm lesion in the right upper lung field. There are no previous x-rays of the patient available. Which of the following is the most appropriate next step in management?", "answer": "CT scan of the chest", "options": {"A": "Follow-up x-ray of the chest in 12 months", "B": "Follow-up x-ray of the chest in 6 months", "C": "Positron emission tomography", "D": "CT scan of the chest", "E": "Reassurance"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 62-year-old woman presents to a clinic with complaints of a worsening rash on her back, fevers with chills, and rigor for 2 days. She denies any headaches, nausea, or vomiting. She is currently on chemotherapy for multiple myeloma, which was diagnosed last year. On examination, there were multiple punched-out ulcers covered in crusts surrounded by raised, violaceous margins on her back. Some of the lesions have black necrotic centers. The vital signs include: temperature 38.8°C (102.0°F), respirations 24/min, pulse 110/min, and blood pressure 100/90 mm Hg. Laboratory studies show:\nHemoglobin 8.4 g/dL\nWhite blood cell (WBC) count  1,500/mm3\nPlatelets 300,000/mm3\nWhich of the following organisms is most likely responsible for this patient’s condition?", "answer": "Pseudomonas aeruginosa", "options": {"A": "Pseudomonas aeruginosa", "B": "Staphylococcus aureus", "C": "Streptococcus pneumoniae", "D": "Haemophilus influenzae", "E": "Streptococcus pyogenes"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "An 8-year-old boy developed nausea, abdominal pain, and watery diarrhea 6 hours after consuming homemade mushroom soup. The boy is rushed to the emergency department. He is severely dehydrated and his blood pressure is 60/40 mm Hg. He is managed with intravenous fluids and other supportive treatment. The mushrooms in the soup had been picked from his family's backyard, and samples of mushrooms were sent to the lab for analysis. The lab reports confirmed that the mushrooms contained some kind of toxin. Which of the following enzymes is most likely inhibited by this toxin?", "answer": "RNA polymerase II", "options": {"A": "Topoisomerase II", "B": "DNA gyrase", "C": "RNA polymerase II", "D": "RNA polymerase I", "E": "RNA polymerase III"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 6-year-old girl is brought to the physician because of generalized fatigue and dark urine for 4 days. Four weeks ago, she was treated with cephalexin for a skin infection. Her temperature is 37°C (98.6°F) and blood pressure is 132/89 mm Hg. Physical examination shows 1+ pretibial edema bilaterally. Her serum creatinine is 1.7 mg/dL. Urine studies show:\nBlood 2+\nProtein 2+\nRBC 12–14/hpf with dysmorphic features\nRBC casts numerous\nWhich of the following is the most likely cause of these findings?\"", "answer": "Granular subepithelial immune complex deposition", "options": {"A": "Granular subepithelial immune complex deposition", "B": "Systemic amyloid protein aggregation", "C": "Defective circulating IgA antibodies", "D": "Anti-type IV collagen antibody formation", "E": "DNA-anti-DNA antibody immune complex formation"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 7-year-old girl is brought to the physician by her mother for a 6-month history of irritability. She has no history of significant illness and is up-to-date on her immunizations. She appears markedly lethargic. Her vital signs are within normal limits. Physical examination shows subconjunctival pallor. Her hemoglobin concentration is 9.2 g/dL and mean corpuscular volume is 76 μm3. A photomicrograph of a wet stool mount is shown. Which of the following infectious agents is the most likely cause of these findings?", "answer": "Necator americanus", "options": {"A": "Necator americanus", "B": "Ascaris lumbricoides", "C": "Enterobius vermicularis", "D": "Trichuris trichiura", "E": "Taenia solium"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 15-year-old girl is brought to the physician by her mother because of a 3-day history of lower abdominal pain. Over the past 9 months, she has had multiple similar episodes of abdominal pain, each lasting for 4–5 days. Menarche has not yet occurred. Examination shows suprapubic tenderness to palpation. Pubic hair and breast development are Tanner stage 4. Pelvic examination shows bulging, bluish tissue 1 cm inside the vaginal introitus. Which of the following is the most likely diagnosis?", "answer": "Imperforate hymen", "options": {"A": "Labial adhesions", "B": "Androgen insensitivity", "C": "Endometriosis", "D": "Imperforate hymen", "E": "Müllerian agenesis"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 6-year-old boy presents with high fever, sore throat, and cough for the past day. The patient’s mother also says he is complaining of generalized muscle aches and chills. Past medical history is significant for childhood asthma, managed with inhaled mometasone furoate. The patient’s temperature is 39.1°C (102.3°F), pulse is 120/min, and respiratory rate is 20/min. On physical examination, his oropharynx is erythematous with mild swelling of the pharyngeal tonsils. Chest auscultation reveals crepitus over the lung bases bilaterally. There are no signs of respiratory distress. Rapid diagnostic testing for influenza B infection in this patient is positive. In addition to symptomatic treatment, which of the following antiviral drugs would most likely benefit this patient?", "answer": "Oseltamivir", "options": {"A": "Amantadine", "B": "Ribavirin", "C": "Rimantadine", "D": "Oseltamivir", "E": "Zanamivir"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 38-year-old woman presents to the emergency department with nausea and progressive right upper quadrant abdominal pain for the past day. For the past year, she has had occasional pain in her right upper quadrant which is often relieved on its own after a few hours. She was recently diagnosed with multiple gallstones for which she underwent an elective uncomplicated endoscopic retrograde cholangiopancreatography (ERCP) 3 days ago. Past medical history is otherwise unremarkable. On physical examination, there is tenderness over the epigastrium with no guarding or rebound. Vital signs include blood pressure 110/68 mm Hg, pulse 98/min, temperature 36.2°C (97.2°F), and respiratory rate 11/min. Laboratory tests are pending. An imaging study of the abdomen confirms the most likely diagnosis. Which of the following is most likely to be below the normal range in her blood due to her current condition?", "answer": "Calcium", "options": {"A": "Trypsinogen", "B": "C-reactive protein", "C": "Lipase", "D": "Glucose", "E": "Calcium"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 42-year-old woman comes to the emergency department because of hematuria and pain in both flanks. She has a history of recurrent urinary tract infections. She also complains of swelling of both feet and facial puffiness. She has passed urinary stones twice before. Her mother also has a history of urinary stone and underwent a kidney transplant. Her temperature is 38.0°C (100.4°F), pulse is 110/min, and blood pressure is 150/98 mm Hg. Abdominal examination shows palpable, bilateral flank masses. Results of a complete blood count are within the reference range. Her serum creatinine concentration is 2.7 mg/dL. Which of the following additional findings is most likely to be seen in this patient?", "answer": "Multiple hepatic cysts", "options": {"A": "Osteolytic bone lesions", "B": "Multiple hepatic cysts", "C": "Mitral valve stenosis", "D": "Popliteal aneurysm", "E": "Vesicoureteral reflux"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 51-year-old man with a past medical history of peptic ulcer disease currently treated via outpatient triple therapy presents to the urgent care center complaining of acute abdominal pain which began suddenly less than 2 hours ago. The physical examination shows his abdomen to be mildly distended, diffusely tender to palpation, and positive for rebound tenderness. Physical exam is unremarkable. The vital signs include: temperature 36.7°C (98.0°F), blood pressure 96/54 mm Hg, heart rate 112/min, and respiratory rate 19/min. Given the following options, what is the next best step in patient management?", "answer": "CT abdomen and pelvis", "options": {"A": "Abdominal radiographs", "B": "CT abdomen and pelvis", "C": "Upper endoscopy", "D": "H. pylori testing", "E": "Serum gastrin level"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 10-month-old boy is brought to the physician because of fever and a cough for 3 days. He was treated for otitis media 3 and 4 months ago. He was also treated for pneumococcal pneumonia and H. influenzae meningitis this past month. He was delivered at term. Pregnancy and neonatal period were uncomplicated. He was breast-fed until 6 months of age. He has a maternal uncle who died of recurrent respiratory tract infections at 28 years of age. He is at the 20th percentile for height and the 10th percentile for weight. His temperature is 39°C (102.2°F), pulse is 122/min, and respirations are 44/min. Examination shows crackles at the left lung base. Palatine tonsils are absent. An x-ray shows an infiltrate in the left lower lung lobe. Flow cytometry shows absence of B-cells. Which of the following is mostly responsible for this patient's late onset of symptoms?", "answer": "Maternal IgG decreases by 6 months", "options": {"A": "Breastfeeding until 6 months", "B": "Reduced T-cell receptor excision circles by 6 months", "C": "Involution of the thymus begins at 6 months", "D": "Splenic dysfunction occurs by 6 months", "E": "Maternal IgG decreases by 6 months"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 55-year-old right-handed woman is being evaluated for a long history of numbness and tingling in both of her hands, particularly in the third digits, that is worse at night. She works as a medical office assistant in a local travel medicine clinic. Her past medical history is significant for hypothyroidism, managed medically with thyroxine. Physical examination showed thenar eminence atrophy, decreased sensation in the 3 first digits of both hands that extends proximally, and weakness on thumb abduction and thumb opposition; deep tendon reflexes are normal. Phalen and Tinel tests are positive. Which of the following is the most inclusive list of spinal roots that contribute to the affected nerve in this patient?", "answer": "C5, C6, C7, C8, T1", "options": {"A": "C5, C6, C7", "B": "C4, C5", "C": "C6, C7, C8", "D": "C3, C4, C5", "E": "C5, C6, C7, C8, T1"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 7-year-old girl is referred to a pediatric cardiologist after a heart murmur was auscultated during a routine school health examination. The patient has not experienced any symptoms of shortness of breath, fatigue, chest pain, or palpitations. She is healthy, does not have any significant medical history, and had an uneventful birth without any complications. Her vital signs are as follows: T 37.2 C, HR 92, BP 104/62, RR 24, SpO2 99%. Physical examination is significant for a midsystolic ejection murmur heard best at the 2nd intercostal space near the left sternal border, a loud S1 heart sound, a widely fixed split S2 heart sound, and no evidence of cyanosis or clubbing. An echocardiogram is conducted and reveals a left-to-right shunt across the interatrial septum. Surgical correction of this patient's condition will most likely prevent which of the following from developing later in life?", "answer": "Pulmonary hypertension", "options": {"A": "Arteriovenous fistula", "B": "Pulmonary stenosis", "C": "Coronary artery disease", "D": "Pulmonary hypertension", "E": "Aortic root dilation"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 21-year-old man is brought to the emergency department by the police because of altered mental status. The police found him covering his ears and shouting near a highway rest area. Upon questioning, he was unable to look directly at the police and answer coherently. On the way to the hospital, he reported feeling nauseous and vomited twice. His temperature is 38.2°C (100.8°F), pulse is 100/min, respirations are 28/min, and blood pressure is 110/77 mm Hg. He is admitted to the hospital for evaluation. Three hours after admission, he has a tonic-clonic seizure. Laboratory studies show:\nSerum\nNa+ 140 mEq/L\nCl- 102 mEq/L\nArterial blood gas analysis on room air:\nOn admission Three hours later\npH 7.47 7.39\nPaCO2 24 mm Hg 31 mm Hg\nPO2 84 mm Hg 82 mm Hg\nHCO3- 20 mEq/L 18 mEq/L\nWhich of the following is the most likely explanation of the patient's laboratory findings?\"", "answer": "Salicylate toxicity", "options": {"A": "Opioid overdose", "B": "Salicylate toxicity", "C": "Diabetic ketoacidosis", "D": "Recurrent vomiting", "E": "Adrenal insufficiency"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 58-year-old man makes an appointment with his nephrologist because he has been feeling weak and increasingly fatigued over the last month. Specifically, he has not been able to do activities of daily living independently because he feels short of breath after several minutes of activity. His past medical history is significant for rapidly progressive glomerulonephritis that led to kidney failure. He has been on hemodialysis for the last 6 months and has been compliant with attending every dialysis session. Physical exam reveals conjunctival pallor. Laboratory tests are obtained and results are shown below:\n\nHemoglobin: 8.9 g/dL (normal: 13.5-17.5 g/dL)\nPlatelet count: 198,000/mm^3 (normal: 150,000-400,000/mm^3)\nMean corpuscular volume: 87 µm^3 (normal: 80-100 µm^3)\nReticulocyte count: 0.1% (normal: 0.5-1.5%)\n\nBased on these findings, the patient is given appropriate treatment to address his symptoms. Which of the following is the most likely mechanism of action for this treatment?", "answer": "Activation of receptors on erythroid progenitor cells", "options": {"A": "Activation of receptors on erythroid progenitor cells", "B": "Chelation of heavy metals", "C": "Provision of finished blood products", "D": "Removal of red blood cell clearing organ", "E": "Transplantation of new cells"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 33-year-old African American woman comes to the physician because of a 4-month history of progressive fatigue, shortness of breath, constipation, and a nonproductive cough. She returned from a trip to Nigeria 6 months ago. Physical examination is unremarkable. Serum calcium concentration is 11.7 mg/dL. An x-ray of the chest shows bilateral hilar lymphadenopathy with coarse, nodular opacities in both lower lobes. A photomicrograph of a biopsy specimen of the affected area of the lungs is shown. Which of the following best describes the pathogenesis of this patient's histopathological findings?", "answer": "TNF-α secretion by CD4+ T cells", "options": {"A": "MHC I binding to CD8+ T cells", "B": "Antigen binding to IgM", "C": "TGF-β secretion by regulatory T cells", "D": "TNF-α secretion by CD4+ T cells", "E": "IL-5 secretion by Th2 cells"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 15-day-old female newborn is brought to the physician for evaluation of red eyes with discharge for 3 days. She was born at 37 weeks' gestation to a 26-year-old woman. Pregnancy and delivery were uncomplicated. The mother received irregular prenatal care during the 3rd trimester of pregnancy. Examination of the newborn shows watery discharge in both eyes and mild eyelid swelling. Which of the following is the most likely cause of this patient's presentation?", "answer": "Chlamydia trachomatis", "options": {"A": "Silver nitrate exposure", "B": "Staphylococcus aureus", "C": "Chlamydia trachomatis", "D": "Neisseria gonorrhoeae", "E": "Herpes simplex virus 2"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "An investigator is studying central nervous system neurotransmitters in mice. He injects the spinal cord with a protease that cleaves SNARE proteins, thereby blocking the release of neurotransmitters from the Renshaw cells in the spinal cord. Which of the following consequences would be expected?", "answer": "Spastic paralysis", "options": {"A": "Disinhibited behavior", "B": "Hydrophobia", "C": "Positive Kernig sign", "D": "Spastic paralysis", "E": "Ascending flaccid paralysis"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 32-year-old G2P2 at 33 weeks and 4 days of gestation presents to the emergency room with low-grade fever, mild low back pain, and dysuria for 1 day. She has a history of urinary tract infections, including one during this current pregnancy that was treated successfully with cephalexin. On examination, she is nontoxic but mildly uncomfortable; she has CVA tenderness on her right side. Her urinalysis is positive for leukocyte esterase and nitrites, and she is admitted to the hospital for IV antibiotics with ceftriaxone. Her present condition places her at increased risk for which of the following:", "answer": "Preterm labor", "options": {"A": "Low birth weight", "B": "Pre-eclampsia", "C": "Postpartum hemorrhage", "D": "Preterm labor", "E": "Post-term labor"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 16-year-old African-American boy is brought to the physician because of a 2-month history of progressive right shoulder pain. He has had many episodes of joint and bone pain in the past, and as a child, had recurrent painful swelling of his hands and feet. His brother had a stroke at 6 years of age and now has an intellectual disability. The patient is at the 60th percentile for height and 55th percentile for weight. His vital signs are within normal limits. Physical examination shows tenderness of the right anterior humerus without noticeable swelling or skin changes. Active and passive range of motion of the right shoulder is decreased and there is pain with movement. The leukocyte count is 4600/mm3. An x-ray of the right shoulder shows subchondral lucency of the humeral head with sclerosis and joint space narrowing. Which of the following is the most likely explanation for this patient's symptoms?", "answer": "Infarction of the bone trabeculae", "options": {"A": "Infection of the dermis and subcutaneous tissue", "B": "Infection of the bone", "C": "Crystal deposition within the joint", "D": "Infarction of the bone trabeculae", "E": "Loss of bone mineral density"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 50-year-old woman comes to the emergency department after waking up with facial swelling and with difficulties swallowing. She was recently diagnosed with hypertension and started on an antihypertensive drug. She follows a strict vegetarian diet. Her pulse is 110/min and blood pressure is 135/85 mm Hg. Physical examination shows marked edematous swelling of the face, lips, and tongue. There is no rash. Serum C4 levels are within the reference range. Which of the following is the most likely cause of this patient's symptoms?", "answer": "Impaired breakdown of kinins", "options": {"A": "Deficiency of C1 esterase inhibitor", "B": "Scombroid poisoning", "C": "Antibody-mediated cytotoxic reaction", "D": "Nonimmunologic release of histamine", "E": "Impaired breakdown of kinins"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "An 82-year-old man presents to the primary care physician with complaints of urinary leakage over the last 2 months. The leakage occurred without any additional symptoms. He has a history of prostatic hyperplasia. The vital signs include: blood pressure 140/90 mm Hg, heart rate 84/min, respiratory rate 18/min, and temperature 36.6°C (98.0°F). Physical examination reveals a palpable and distended bladder. Urinalysis reveals:\nColor Yellow\nClarity/turbidity Clear\npH 5.5\nSpecific gravity 1.015\nNitrites Negative\nLeukocyte esterase Negative\nWhich of the following is the best initial management for this patient?", "answer": "Bladder catheterization", "options": {"A": "Anticholinergics", "B": "Surgery", "C": "Bladder catheterization", "D": "Tamsulosin", "E": "Pelvic floor muscle training"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 25-year-old female presents to her geneticist due to the fear that she may have inherited her father's disease. He was diagnosed at the age of 41 when his symptoms of chorea, coordination problems, and cognitive decline begin to occur. He was diagnosed with a disease resulting from the expansion of CAG repeats on chromosome 4 and later developed severe dementia and died at the age of 56. The daughter was found to have double the amount of CAG repeats and was told by the geneticist that she may have an earlier onset with increased severity of disease. What phenomenon describes this?", "answer": "Anticipation", "options": {"A": "Variable expression", "B": "Incomplete penetrance", "C": "Pleiotropy", "D": "Anticipation", "E": "Heteroplasmy"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 25-year-old man presents to the emergency department after being rescued from a house fire 30 minutes ago. He is conscious and in distress. On examination, he is noted to have 1st-degree burns involving 54% of his total body surface area. He has type 1 diabetes and takes insulin every day. He is admitted to the burn unit and treated appropriately. Ten days after admission, the physician notices blue-green pus oozing from the burn wounds. He is afebrile with a pulse of 90/min and a blood pressure of 130/80 mm Hg. A sample exudate is collected with a sterile swab and sent to the laboratory for culture, which yields the growth of aerobic gram-negative rods. Which of the following antibiotics will be most effective in treating this patient’s condition?", "answer": "Piperacillin with gentamicin", "options": {"A": "Azithromycin with rifampin", "B": "Piperacillin with gentamicin", "C": "Piperacillin", "D": "Ticarcillin", "E": "Azithromycin"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 67-year-old man with a past medical history of obesity and diabetes presents to the emergency department with fatigue. The patient has become more confused over the past several days and has been urinating profusely. His temperature is 99.0°F (37.2°C), blood pressure is 120/68 mmHg, pulse is 160/min, respirations are 19/min, and oxygen saturation is 98% on room air. Physical exam is notable for a confused man with dry mucous membranes. He is unable to answer simple questions and is moving all extremities spontaneously. Which of the following is also likely to be found in this patient?", "answer": "Blurred vision", "options": {"A": "Blurred vision", "B": "Meningeal symptoms", "C": "Seizures", "D": "Tremulousness", "E": "Unilateral weakness"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 42-year-old man presents with acute onset jaundice. Past medical history is significant for COPD diagnosed 4 years ago, managed medically, and admission for acute pancreatitis 6 months ago. The patient denies any history of smoking, alcohol use or recreational drugs. Which of the following is the most likely etiology of liver damage in this patient?", "answer": "α1-antitrypsin (AAT) deficiency", "options": {"A": "α1-antitrypsin (AAT) deficiency", "B": "Gilbert syndrome", "C": "Glucose-6-phosphate dehydrogenase deficiency (G6PD deficiency)", "D": "Dubin–Johnson syndrome", "E": "Hepatitis C"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "An 8-year-old girl presents to the emergency department with respiratory distress, facial edema, and a skin rash after eating a buffet dinner with her family. Her parents say they were eating at a seafood buffet when, all of a sudden, the patient began to cough and feel short of breath. They say nothing like this has ever happened before. The patient has a history of seasonal allergies for which she occasionally takes cetirizine. Her blood pressure is 80/52 mm Hg; heart rate, 122/min; and respiratory rate, 22/min. On physical examination, the patient has severe edema over her face and audible stridor. Of the following options, which is the most appropriate next step in the management of this patient?", "answer": "Intramuscular epinephrine", "options": {"A": "Intramuscular epinephrine", "B": "Oral diphenhydramine", "C": "Intravenous epinephrine", "D": "Extra-strength topical diphenhydramine", "E": "Inhaled sodium cromolyn"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 33-year-old man presents to his physician complaining of a small mass he noticed in his scrotum about 1 month ago. The mass feels loosely attached to the right testicle and is firm, and not painful. He has no history of a serious illness and takes no medications. He is married with 2 children. His vital signs are within normal limits. Examination shows a 1-cm spherical mass in the superior part of the right testis that has a smooth border. It transilluminates with a flashlight. The mass does not enlarge when the patient coughs or bears down. Scrotal ultrasonography shows an extratesticular hypoechoic mass near the epididymal head of the right testicle with posterior acoustic enhancement and without internal shadows. Which of the following is the most appropriate next step in management?", "answer": "No therapy at this time", "options": {"A": "Ceftriaxone + doxycycline", "B": "Ligation of processus vaginalis", "C": "Microsurgical varicocelectomy", "D": "Orchiectomy", "E": "No therapy at this time"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 51-year-old asymptomatic woman undergoes colposcopy due to a high-grade intraepithelial lesion based on a Pap smear. Colposcopy shows a visible lesion 2 cm in diameter located on the posterior cervical lip and confined to the cervix with sharp borders, a coarse mosaic pattern after application of acetic acid, and contact bleeding. The histologic evaluation of the biopsy shows glandular epithelial cells with nuclear hyperchromasia and enlargement, increased mitoses, a fusion of glands, and stromal infiltration to 8 mm. The chest X-ray and abdominal ultrasound are negative for any additional findings. Which of the following interventions is a proper management strategy for the presented patient?", "answer": "Modified radical (Wertheim) hysterectomy", "options": {"A": "Loop electrosurgical excision procedure (LEEP)", "B": "Simple hysterectomy", "C": "Modified radical (Wertheim) hysterectomy", "D": "Platinum-based chemotherapy", "E": "Simple hysterectomy with bilateral salpingo-oophorectomy"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 65-year-old man presents to the Emergency Department complaining of substernal chest pain. An acute coronary event is suspected and a coronary catheterization procedure reveals an atherosclerotic plaque in the patient's left anterior descending artery. In the formation of an atherosclerotic plaque, which of the following pairings is correct?", "answer": "Smooth muscle cells (SMC) -- extracellular matrix (ECM) deposition", "options": {"A": "Fibroblasts -- foam cells", "B": "Smooth muscle cells (SMC) -- extracellular matrix (ECM) deposition", "C": "Endothelial cells -- downregulation of VCAM-1", "D": "Smooth muscle cells -- migration from intima to media", "E": "LDL chemical reduction -- endothelial dysfunction"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 15-year-old boy is brought to the physician by his mother because of a 2-month history of pain in his left hip. The pain started suddenly and has worsened over the past 2 weeks. The pain radiates down the thigh and is aggravated by movement. He had a fall while cycling around a month ago. He had a urinary tract infection 3 months ago that resolved with trimethoprim/sulfamethoxazole. There is no family history of serious illness. His immunizations are up-to-date. He is 165 cm (5 ft 5 in) tall and weighs 85 kg (187 lb); BMI is 31.2 kg/m2. His temperature is 37.5°C (99.5°F), pulse is 65/min, and blood pressure is 104/70 mm Hg. Examination shows an antalgic gait. The left groin is tender to palpation and internal rotation is limited due to pain. Flexing the hip causes external rotation and abduction. His leukocyte count is 9,800/mm3 and erythrocyte sedimentation rate is 12 mm/h. An x-ray of the pelvis is shown. Which of the following is the most appropriate next step in management?", "answer": "Surgical pinning of femoral head", "options": {"A": "Long leg cast", "B": "Intravenous antibiotic therapy", "C": "Surgical pinning of femoral head", "D": "Intra-articular lidocaine", "E": "Proximal femoral osteotomy"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 58-year-old man is hospitalized and treated with clindamycin for a pulmonary abscess. During his hospital stay he develops abdominal pain and bloody diarrhea, and has a WBC of 14,000; serum creatinine is 0.9 mg/dL. On teaching rounds, you learn that the responsible pathogen produces a multi-unit toxin that binds to the colonic mucosa, causing actin depolymerization that results in cell death and mucosal necrosis. What is the preferred treatment for this condition?", "answer": "Metronidazole", "options": {"A": "Continue Clindamycin", "B": "Metronidazole", "C": "Penicillin G", "D": "Tetracycline", "E": "Erythromycin"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 61-year-old Caucasian woman presents to her physician for a routine checkup. She has primary hypertension and rheumatoid arthritis. She currently does not report any relevant symptoms, such as weight change, increased or decreased appetite, sleep or mood problems, gastrointestinal symptoms, fever, or night sweats. Her medications include valsartan 160 mg, hydrochlorothiazide 25 mg daily, and methylprednisolone 28 mg every other day. According to her diary, her blood pressure varies from 130/80 to 120/60 mm Hg. In the past year, she had humeral and tibial fractures from a self-height fall and stepping over a fence, respectively, that occurred 6 months apart. She is in menopause and is not on hormone replacement therapy. Currently, she does not smoke but has a 10-pack-year history of smoking. She consumes alcohol occasionally. She weighs 56 kg (123.5 lb), and her height is 169 cm (5 ft 7 in). She does not report a family history of any cancer. Her father died after a myocardial infarction at the age of 63. She performs daily household activities but is not engaged in either aerobic or strength training. She mainly consumes vegetables, cereals, and dairy products. Her blood pressure is 125/80 mm Hg, heart rate is 67/min, respiratory rate is 14/min, and temperature is 36.5°C (97.7°F). Her physical examination is unremarkable. Which result would you expect to find on her screening tests?", "answer": "T score –2.01 on DEXA scan", "options": {"A": "A score of 17 on PHQ-9 test", "B": "T score –2.01 on DEXA scan", "C": "Dilation of the abdominal aorta on ultrasound examination", "D": "Presence of a tumor on colonoscopy", "E": "Presence of focal hyperintensities on mammography"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 24-year-old man is brought to the emergency department by his sister because she has noticed that he has been behaving differently over the past 4 weeks. Today, the patient attempted to set their house on fire while yelling that he was trying to “save us all.” The patient has a history of psychotic symptoms treated with aripiprazole. His sister states that he stopped taking his medications about 3 weeks ago. He works as a dishwasher but has not been to work for several days. His vital signs are within normal limits. Mental status examination shows a blunted affect. Throughout the interview, the patient continuously stares at the ceiling and makes little eye contact with the physician. When asked about the incident today, he states that he has been hearing the voice of “the great one” who has informed him that aliens are in his neighborhood in the form of rats and cockroaches that need to be “torched to prevent the alien invasion.” He is refusing treatment and insists on going home. Which of the following is the most appropriate next step in management?", "answer": "Involuntarily hospitalize the patient", "options": {"A": "Administer aripiprazole and follow-up after 24 hours", "B": "Refer the patient to a psychologist for cognitive behavioral therapy", "C": "Involuntarily hospitalize the patient", "D": "Report the patient to the local police", "E": "Ask the patient's sister to convince him to stay overnight"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 13-year-old girl is brought to the emergency department by her father because of a severe nosebleed. She takes no medications and has no history of serious medical illness but has had frequent nosebleeds in the past. Physical examination shows brisk bleeding from the right nare and pooled blood in the posterior pharynx. Laboratory studies show:\nHemoglobin 8 g/dL\nPlatelet count 195,000/mm3\nProthrombin time 12 sec\nPartial thromboplastin time 49 sec\nFibrin split products negative\nThe bleeding time is 11 minutes. Which of the following is the most appropriate pharmacotherapy?\"", "answer": "Desmopressin", "options": {"A": "Prothrombin complex concentrate", "B": "Phytonadione", "C": "Rituximab", "D": "Desmopressin", "E": "Intravenous immunoglobulin"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 33-year-old man presents to the emergency department with joint pain. He states that since yesterday he has had joint pain, and today he noticed a rash. The patient does not have a significant past medical history. The patient smokes cigars, drinks 1 to 4 drinks per day, is sexually active, and uses cocaine occasionally. His temperature is 101°F (38.3°C), blood pressure is 125/65 mmHg, pulse is 80/min, respirations are 14/min, and oxygen saturation is 98% on room air. Physical exam reveals pustular skin lesions and an inflamed and painful right knee that is warm to the touch. Which of the following is the most appropriate treatment for the most likely diagnosis?", "answer": "Cefixime and azithromycin", "options": {"A": "Azithromycin", "B": "Cefixime and azithromycin", "C": "Ceftriaxone", "D": "Ceftriaxone and vancomycin", "E": "Piperacillin and tazobactam"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 20-year-old woman presents to a physician following unprotected coitus with her boyfriend about 10 hours ago. She tells the physician that although they usually use a barrier method of contraception, but this time they did not. She does not want to become pregnant. She also mentions that she has been diagnosed with major depression and does not want to take an estrogen-containing oral contraceptive pill. After counseling, the physician prescribes an enteric-coated pill containing 1.5 mg of levonorgestrel. Which of the following is the primary mechanism of action of levonorgestrel?", "answer": "Delayed ovulation through inhibition of follicular development", "options": {"A": "Delayed ovulation through inhibition of follicular development", "B": "Thickening of cervical mucus", "C": "Atrophy of endometrium", "D": "Mucosal hypertrophy and polyp formation in cervix", "E": "Reduction in motility of cilia in fallopian tubes"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 4-year-old girl is brought to the emergency department because of colicky abdominal pain for 1 day. She has had two similar episodes in the past. Urinalysis shows red blood cells and hexagonal-shaped crystals. Urine sodium cyanide nitroprusside test is positive. Further evaluation of this patient is most likely to show which of the following findings?", "answer": "Impaired intestinal ornithine reabsorption", "options": {"A": "Increased stool fat content", "B": "Inability of intercalated cells to secrete H+", "C": "Increased urine homocysteine levels", "D": "Impaired intestinal ornithine reabsorption", "E": "Urease-positive bacteria in the renal pelvis"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 49-year-old woman, gravida 1, para 1, comes to the physician because of shorter and less frequent menstrual periods over the past year. During this time, she has also had frequent mood swings and a 2.5-kg (5-lb) weight loss. She occasionally wakes up at night because she is too warm and sweating profusely. These episodes are followed by chills and anxiety that subside within minutes. She has no history of abnormal Pap smears. She is sexually active with her husband, who had a vasectomy 10 years prior. She is 163 cm (5 ft 3 in) tall and weighs 70 kg (154 lb); BMI is 26 kg/m2. Her temperature is 37°C (98.6°F), pulse is 103/min, respirations are 16/min, and blood pressure is 129/84 mm Hg. Abdominal and genitourinary examination shows no abnormalities. Which of the following is the most appropriate next step in management?", "answer": "Measure serum TSH concentration", "options": {"A": "Offer hormone replacement therapy", "B": "Perform transvaginal ultrasound", "C": "Measure serum β-hCG concentration", "D": "Obtain endometrial biopsy", "E": "Measure serum TSH concentration"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "An 8-year-old boy is brought by his parents to the emergency department with a tender and swollen right leg. The boy said that he was playing soccer when he accidentally kicked a metal goal post. The boy was born at 39 weeks gestation via spontaneous vaginal delivery. He is up to date on all vaccines and is meeting all developmental milestones. A review of his medical history reveals that he had a fracture of the left tibia at 4-years-old and a fracture of the right radius 6 months ago. Neither of the two was associated with major trauma and both healed well. At the hospital, his vital signs are stable and his sclerae are white-blue. There is no muscular hypotonia. His height and weight are normal for his age and sex and the skin is normal. A tender swelling is present over his right leg and he can not put weight on that leg. The radiograph of his right leg confirms a fracture of the shaft of the tibia at the junction of its upper one-third and lower two-thirds. The clinician suspects physical abuse and orders a skeletal survey. Which of the following findings is most likely to be detected in a skeletal survey?", "answer": "Wormian bones in the skull", "options": {"A": "A healed right scapular fracture", "B": "Ground-glass appearance of the cortices of the long bones", "C": "Widening and cupping of the metaphyses of the long bones", "D": "Wormian bones in the skull", "E": "Mandibular asymmetry"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A previously healthy 34-year-old man comes to the physician because of loose stools for the past 4 months. On average, he has 1 episode of loose non-bloody bowel movement with abdominal cramps each day around noon. He has no diarrhea when he does not have breakfast in the morning. He also complains of excess flatus but no bowel incontinence or urgency. He has had no fever or weight loss. His symptoms are not associated with stress. He has had no overseas or mountainous trips over the past year. He takes no medications. His vital signs are within normal limits. Physical examination shows no abnormalities. Which of the following is the most appropriate initial recommendation?", "answer": "Elimination of all dairy products", "options": {"A": "Gluten-free diet", "B": "Cholestyramine", "C": "Elimination of all dairy products", "D": "Empirical therapy with metronidazole", "E": "Loperamide"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 37-year-old male with a history of diabetes is prescribed a drug that would decrease the risk of the patient developing glomerular renal capillary damage, nodular glomerular sclerosis, and eventual nephrotic syndrome. After some time being on this medication, the patient complains of a bad cough. Which of the following physiologic changes is most likely expected after being prescribed that medication?", "answer": "Decreased aldosterone, decreased GFR, increased renal plasma flow, increased bradykinin", "options": {"A": "Decreased aldosterone, decreased GFR, decreased renal plasma flow, increased bradykinin", "B": "Increased aldosterone, increased GFR, decreased renal plasma flow, increased bradykinin", "C": "Decreased aldosterone, decreased GFR, decreased renal plasma flow, decreased bradykinin", "D": "Decreased aldosterone, decreased GFR, increased renal plasma flow, increased bradykinin", "E": "Increased aldosterone, increased GFR, increased renal plasma flow, increased bradykinin"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 69-year-old woman presents with insomnia and altered mental status. The patient is accompanied by her husband who says her symptoms began acutely 4 days ago with no obvious trigger and have not improved. Before this point, she had been living independently with no signs of cognitive impairment. The patient’s husband says that the patient is often non-compliant with medication and eats and drinks little unless prompted. Past medical history is significant for hypertension, diabetes mellitus type 2, chronic pyelonephritis, and depression. Current medications are aspirin, metoprolol, hydrochlorothiazide, losartan, metformin, and trazodone. Vitals include: temperature 38.1℃ (100.6℉), blood pressure 130/70 mm Hg, pulse 91/min, respiratory rate 17/min, and oxygen saturation 99% on room air. On physical examination, the patient is agitated and easily distracted. Oriented x 1. She believes it is 1967, and she is at the bookstore. She talks to non-existent people and uses words inappropriately. Cardiac sounds are muffled but otherwise normal. Lungs are clear to auscultation. On abdominal examination, the tip of the urinary bladder can be palpated. Costovertebral angle tenderness is present bilaterally. Catheterization of the bladder yields cloudy, foul-smelling urine. Urinalysis is pending. Which of the following would be the best treatment for this patient’s change in mental status?", "answer": "Antibiotic therapy", "options": {"A": "Changing trazodone to amitriptyline", "B": "Lifelong administration of rivastigmine", "C": "Antibiotic therapy", "D": "Discontinuation of metoprolol", "E": "Lifelong administration of memantine"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 65-year-old man presents to the physician with a concern for several lumps on his jaw. He has a history of dental caries and admits to maintaining poor oral hygiene. On physical examination, he has 3 nontender and indurated masses at the angle of his jaw that are draining thick yellow pus. Microscopy of the drained pus reveals yellow granules filled with bacteria. Which of the following medical treatments is indicated for this patient’s condition?", "answer": "Penicillin", "options": {"A": "Amoxicillin-clavulanate", "B": "Ciprofloxacin", "C": "Dapsone and rifampin", "D": "Penicillin", "E": "Trimethoprim-sulfamethoxazole"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 23-year-old man presents with severe right lower quadrant abdominal pain for the past 2 hours. He says the pain started in the periumbilical region and has now shifted to the lower right quadrant. He describes the pain as spasmodic. Past medical history is insignificant, and the patient denies any history of smoking, alcohol, or drug use. The patient’s vital signs show: pulse 88/min, respiratory rate 18/min, blood pressure 126/84 mm Hg, and temperature 38.4°C (101.0°F). On physical examination, there is severe tenderness to palpation in the right lower quadrant with rebound and guarding. The patient is rushed to the operating room for a laparoscopic appendectomy. The following preoperative laboratory tests are obtained:\nSerum glucose (random) 123 mg/dL\n  Serum electrolytes\nSodium 143 mEq/L\nPotassium 4.7 mEq/L\nChloride 102 mEq/L\n    Serum creatinine 1.7 mg/dL\nBlood urea nitrogen 32 mg/dL\n    Hemoglobin (Hb%) 12.5 g/dL\nMean corpuscular volume (MCV)  80 fl\nReticulocyte count 1%\nErythrocyte count 5.1 million/mm³\nLeukocyte count 14,000/mm³\nNeutrophils 80%\nDuring the induction of anesthesia, isoflurane and a second compound are administered. About 25 minutes after induction, the patient develops significant muscle rigidity and his temperature increases to 40.8°C (105.4°F). The patient’s blood pressure is now 158/94 mm Hg. Which of the following was most likely the second compound administered to this patient?", "answer": "Succinylcholine", "options": {"A": "Atracurium", "B": "Bupivacaine", "C": "Nitrous oxide", "D": "Neostigmine", "E": "Succinylcholine"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 16-year-old boy is brought to the physician because of a 3-week history of loose stools. He has 2–3 episodes of loose stools a day that are occasionally bloody. During this period, he has also had crampy abdominal pain, generalized fatigue, and a 2-kg (5-lb) weight loss. His temperature is 37.1°C (98.8°F), pulse is 82/min, and blood pressure is 106/68 mm Hg. Examination shows mild lower abdominal tenderness to palpation. Test of the stool for ova and parasites is negative. His hemoglobin concentration is 11.8 g/dL, leukocyte count is 12,400/mm3, and erythrocyte sedimentation rate is 14 mm/h. A colonoscopy shows inflamed, friable mucosa extending just beyond the rectum that bleeds on contact with the endoscope. A biopsy confirms the diagnosis. Which of the following is the most appropriate therapy for this patient?", "answer": "Mesalamine therapy", "options": {"A": "Gluten-free diet", "B": "Proctocolectomy", "C": "Mesalamine therapy", "D": "Infliximab therapy", "E": "Cyclosporine therapy\n\""}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 26-year-old man presents with a 6-month history of headaches. Over the past 6 months, he has developed headaches that are 4/10 in intensity and occur every other day for 1–2 hours. The headaches are bilateral and feel like a ‘band is squeezing his head’. He denies photophobia, phonophobia, nausea, and vomiting. He has had no visual loss or photopsia. No significant past medical history. He is an avid weightlifter and works at a moving company, where he is constantly lifting heavy items. Additionally, he recently got his 21-year-old girlfriend and his other 23-year-old girlfriend pregnant, which he says is causing a lot of stress. Physical examination is unremarkable. Which of the following is the next best step in the management of this patient? ", "answer": "Ibuprofen", "options": {"A": "Amitriptyline", "B": "Magnetic resonance image (MRI) of the head", "C": "Ophthalmologic evaluation", "D": "Ibuprofen", "E": "Sumatriptan"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A histologic section is obtained from the central canal of the spinal cord. A special stain is used to identify a specific glial cell that makes up the lining of the central canal and ventricles in the central nervous system. Which of the following best describes the primary function that the cells highlighted in blue serve?", "answer": "Production and circulation of CSF", "options": {"A": "Maintenance of the blood brain barrier", "B": "Production and circulation of CSF", "C": "Protective membrane surrounding spinal cord", "D": "Conduct voluntary muscle action potentials", "E": "Increasing action potential conduction velocity"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 58-year-old man presents to the emergency department with a 4-hour history of severe abdominal pain. He has noted brief episodes of postprandial abdominal pain for the last 2 months, but this pain is much more severe and diffuse. He also reports nausea and has had several episodes of non-bloody, non-bilious emesis since the pain started. Past medical history is notable for hyperlipidemia diagnosed 10 years ago and managed with lifestyle modifications; he has never been hospitalized. Vital signs are unremarkable. Physical examination shows dry mucous membranes and a soft, non-distended abdomen that is diffusely tender. Laboratory tests are notable for a lipase level of 3,125 U/L. CT of the abdomen shows an enlarged gallbladder and peripancreatic fluid with dilation of the pancreatic and common bile ducts. Which of the following is the best next step in the management of this patient?", "answer": "Endoscopic retrograde cholangiopancreatography (ERCP)", "options": {"A": "Cholecystectomy", "B": "Colonoscopy", "C": "Endoscopic retrograde cholangiopancreatography (ERCP)", "D": "Esophagogastroduodenoscopy (EGD)", "E": "Nasogastric tube placement"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 55-year-old man presents to his primary care physician for his annual check-up. He says that he has generally been feeling well; however, he has noticed that he has had some intermittent very low grade fevers of unknown etiology. His past medical history is significant for well-controlled hypertension and diabetes. On physical exam he is found to have painless enlargement of a number of cervical and axillary lymph nodes. A biopsy of the enlarged nodes is obtained and genetic testing shows that part of chromosomes 14 and 18 are joined together. Which of the following would most likely be observed in cells with this genetic change?", "answer": "Decreased release of cytochrome c", "options": {"A": "Decreased activation of CD95", "B": "Decreased activity of p53", "C": "Decreased release of cytochrome c", "D": "Increased activation of Apaf-1", "E": "Increased activation of FADD"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 75-year-old man is brought to the emergency room because of dizziness and palpitations for the past hour. His pulse is 185/min and blood pressure is 100/52 mm Hg. An ECG shows a narrow-complex, regular tachycardia without P waves. A drug is administered that activates cardiac potassium channels and causes transient atrioventricular block. Which of the following adverse effects is most likely to occur?", "answer": "Chest pain", "options": {"A": "Sedation", "B": "Chest pain", "C": "Dry cough", "D": "Perioral paresthesia", "E": "Yellow vision"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 70-year-old man is brought to the emergency department with painful discharge from his right ear with difficulty hearing for 3 days. His temperature is 39.5°C (103.1°F) and pulse is 120/minute. Physical examination shows mild facial asymmetry with the right corner of his mouth lagging behind the left when the patient smiles. There is severe ear pain when the right auricle is pulled superiorly. Otoscopic examination shows granulation tissue at the transition between the cartilaginous and the osseous part of the ear canal. Which of the following is most likely associated with this patient's condition?", "answer": "Glucose intolerance", "options": {"A": "Invasive tumor of external auditory canal", "B": "Decreased intracranial perfusion", "C": "Glucose intolerance", "D": "Pus-filled mastoid air cells", "E": "Positive streptococcal culture"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 24-year-old female with a history of recurrent infections, bipolar disorder, and no prenatal care gives birth to a male infant. On physical exam in the delivery room, you observe a tuft of hair over the infant's lumbosacral region. Which of the following drugs was this mother most likely taking during pregnancy?", "answer": "Valproate", "options": {"A": "Chloramphenicol", "B": "Gentamicin", "C": "Lithium", "D": "Valproate", "E": "Folic acid"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 25-year-old woman presents to the physician with the complaint of several episodes of headache in the past 4 weeks that are affecting her school performance. The episodes are getting progressively worse, and over-the-counter headache and migraine medication do not seem to help. She also mentions having to raise her head each time to look at the board when taking notes; she cannot simply glance up with just her eyes while facing her notes. She has no significant past medical or family history and was otherwise well prior to this visit. Ophthalmic examination shows an upward gaze palsy, convergence-retraction nystagmus, and papilledema. What structure is most likely to be affected by this patient's condition?", "answer": "Aqueduct of Sylvius", "options": {"A": "Third ventricle", "B": "Aqueduct of Sylvius", "C": "Tegmentum", "D": "Corpora quadrigemina", "E": "Inferior colliculi"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 75-year-old woman is brought to the emergency department because of a 6-hour history of severe headache, nausea, and 1 episode of vomiting. On arrival, she is lethargic and oriented only to self. Her pulse is 50/min, respirations are 8/min and shallow, and blood pressure is 150/96 mm Hg. Examination shows medial deviation of the left globe and ecchymoses of the upper eyelids. Appropriate pharmacotherapy with an intravenous drug is initiated, and the patient's urine output subsequently increases. The patient is at greatest risk of which of the following adverse effects?", "answer": "Pulmonary edema", "options": {"A": "Drug-induced hypersensitivity syndrome", "B": "Hyperuricemia", "C": "Tinnitus", "D": "Increased intraocular pressure", "E": "Pulmonary edema"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 31-year-old gravida 2 para 2 woman presents to her primary care physician for follow up. Two weeks ago, she gave birth via vaginal delivery to a 9.5 lb (4.3 kg) male infant. The delivery was complicated by a vaginal laceration that required extensive suturing once the infant was delivered. Immediately after delivery of the placenta she experienced intense shaking and chills that resolved within 1 hour. She has felt well since the delivery but admits to 6 days of malodorous smelling vaginal discharge that is tan in color. She has a history of vaginal candidiasis and is worried that it may be recurring. Her temperature is 98.8°F (37.1°C), blood pressure is 122/73 mmHg, pulse is 88/min, respirations are 16/min, and BMI is 33 kg/m^2. Speculum exam reveals a 1.5 cm dark red, velvety lesion on the posterior vaginal wall with a tan discharge. The pH of the discharge is 6.4. Which of the following is the most likely diagnosis?", "answer": "Rectovaginal fistula", "options": {"A": "Bacterial vaginosis", "B": "Endometritis", "C": "Rectovaginal fistula", "D": "Vaginal melanoma", "E": "Vesicovaginal fistula"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 50-year-old male presents to the emergency room after getting hit by a car while biking. He complains of severe pain in both thighs. His thighs appear swollen, bruised, and angulated. Radiographic imaging demonstrates bilateral femoral shaft fractures. He subsequently undergoes surgical fixation of his fractures. Initially he has an uneventful post-operative course; however, on post-op day 4 he becomes confused and develops chest pain, tachypnea, and dyspnea. A new petechial rash is seen over his chest and neck. Electrocardiogram reveals normal sinus rhythm. Which of the following is the most likely cause of this patient’s respiratory symptoms?", "answer": "Occlusion of the pulmonary vessels by fat globules", "options": {"A": "Lobar lung consolidation", "B": "Aspiration of stomach contents", "C": "Occlusion of the left anterior descending artery", "D": "Occlusion of the pulmonary vessels by fat globules", "E": "Spontaneous pneumothorax"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A group of researchers is conducting a study to assess the validity and reliability of patient history in determining the amount and duration of drug abuse. In this study, 60 subjects with hepatitis were asked details of their history of drug abuse, such as the duration of drug abstinence, the amount and duration of drug abuse, and the treatment history. Additionally, a source close to or related to each of the study subjects (most often a spouse) was asked similar questions about the subject by a second researcher who was blinded to the subject’s drug abuse history. Results revealed that the duration of drug abstinence correlated highly between subjects and the source (Spearman’s r = 0.94, p-value < 0.001), as did the individual's score on the stimulant relapse risk scale (SRRS, Spearman’s r = 0.74, p-value < 0.001), a ranked metric of relapse risk. Which of the following statements regarding this results of this study is true?", "answer": "Spearman’s correlation coefficient reveals a strong association between the SRRS scores, as assessed by the study subject and their related source.", "options": {"A": "Spearman’s rank correlation coefficient was used for these data because both of the variables were normally distributed.", "B": "If the authors had conducted a study on larger sample size, Pearson’s correlation coefficient for these data would have been calculated.", "C": "There is a linear relationship between the duration of drug abstinence as assessed by the subject and their close/related source.", "D": "Spearman’s correlation coefficient reveals a strong association between the SRRS scores, as assessed by the study subject and their related source.", "E": "We can conclude that 88.4% (= 0.94 x 0.94) of the variability in the duration of drug abstinence (as assessed by the study subjects) can be 'explained' by the variability in the duration of drug abstinence as assessed by their sources."}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 27-year-old man comes to the emergency department for progressive weakness and numbness in his legs for 5 days. Symptoms originally started with tingling in both feet and have progressed to involve the knees and hips; he is currently unable to walk without assistance. Two weeks ago, the patient had diarrhea that subsided without antibiotics. Neurologic examination shows weakness, decreased sensation, and absent patellar reflexes in both lower extremities. Lumbar puncture shows elevated CSF protein and no white blood cells. Which of the following structures is most likely affected in this patient?", "answer": "Schwann cells", "options": {"A": "Postsynaptic acetylcholine receptors", "B": "Muscle endomysium", "C": "Schwann cells", "D": "Presynaptic terminals of cholinergic neurons", "E": "Cerebral white matter"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 23-year-old man presents to the emergency department presenting with sudden-onset dyspnea and left-sided chest pain over the last hour. This event started when he was in class sitting for an exam. He reports that the pain is worse with inspiration and does not radiate. He says he has anxiety and takes alprazolam as needed. He smokes half a pack of cigarettes a day and drinks alcohol socially. The temperature is 36.7°C (98.0°F), the blood pressure is 130/80 mm Hg, the pulse is 82/min, and the respiratory rate is 14/min. Pulse oximetry shows 97% on room air. The patient’s weight is 63.5 kg (140 lb), height is 185 cm (6 ft 1 in), and he has a BMI of 18.5 kg/m2. A chest X-ray is taken (see exhibit). After an hour of supplemental oxygen, rest, and careful monitoring his dyspnea improves and chest pain resolves without medication. Which of the following is the most appropriate further management of this patient?", "answer": "Supplemental oxygen", "options": {"A": "Needle thoracostomy", "B": "IV antibiotics", "C": "Supplemental oxygen", "D": "CT angiogram of chest", "E": "Lorazepam and follow-up with psychiatry"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 36-year-old male is brought to the emergency department by fire and rescue after being found down in his apartment by his wife. His wife reports that the patient had been complaining of chest pain for the last few hours but refused to go to the hospital. She went to the grocery store for about half an hour and found her husband unresponsive on the ground when she returned home. The patient’s wife reports that his past medical history is significant for a “heart murmur” and that the patient’s father died at age 32 for unknown reasons. In the trauma bay, the patient’s temperature is 98.8°F (37.1°C), blood pressure is 88/41 mmHg, pulse is 116/min, and respirations are 12/min. On physical exam, the patient has a Glascow Coma Score (GCS) of 7. He has a tall stature with long limbs and long, slender fingers. He is also noted to have a pectus deformity. On cardiac exam, the patient has a diastolic decrescendo murmur at the left third intercostal space. He has weak brachial and femoral pulses.\n\nWhich of the following is the most likely etiology of this patient’s presentation?", "answer": "Spontaneous separation in the arterial wall", "options": {"A": "Coronary atherosclerosis", "B": "Hypertrophic cardiomyopathy", "C": "Spontaneous rupture of the aorta", "D": "Spontaneous rupture of the mitral chordae tendinae", "E": "Spontaneous separation in the arterial wall"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 44-year-old man comes to the physician because of severe lower back pain for 1 week. He has also had fatigue, weight gain, and episodic headaches during the past 3 months. He has no history of serious illness and takes no medications. His pulse is 88/min and blood pressure is 155/102 mm Hg. Physical examination shows facial plethora and truncal obesity. The skin appears stretched, with multiple ecchymotic patches over the upper and lower extremities bilaterally. Cardiopulmonary examination shows no abnormalities. There are bilateral paravertebral muscle spasms and severe tenderness over the second lumbar vertebra. An x-ray of the lumbar spine shows decreased bone density and a compression fracture of the L2 vertebra. Further evaluation of this patient is most likely to show which of the following findings?", "answer": "T-wave flattening on ECG", "options": {"A": "Nuchal muscle hypertrophy", "B": "Low serum glucose levels", "C": "Suprasellar mass on cranial MRI", "D": "T-wave flattening on ECG", "E": "Positive Chvostek sign"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "Two weeks after undergoing coronary artery bypass surgery for acute myocardial infarction, a 62-year-old man comes to the physician because of a 4-day history of fever, stabbing chest pain, and fatigue. Initially the pain was only present when he was lying supine, but now it is present all the time and only subsides when he is leaning forward. He has hypertension and mild mitral regurgitation. He has smoked one pack of cigarettes daily for 44 years but quit prior to surgery. Current medications include aspirin, clopidogrel, metoprolol, captopril, and atorvastatin. His temperature is 38.3°C (102°F), pulse is 84/min and regular, respirations are 16/min, and blood pressure is 132/86 mm Hg. During inspiration the blood pressure drops to 117/80 mm Hg. On physical examination there are jugular venous pulsations 4 cm above the sternal angle. Heart sounds are faint. There is 2+ edema in the lower extremities. Which of the following is the most likely cause of this patient's symptoms?", "answer": "Decreased left ventricular diastolic filling", "options": {"A": "Increase in mean aortic pressure", "B": "Left ventricular volume overload", "C": "Decreased left ventricular diastolic filling", "D": "Supraventricular arrhythmia", "E": "Decreased right ventricular contractility\n\""}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 28-year-old woman comes to the physician with her mother because of a 1-week history of feeling unusually energetic. The mother describes her state as “hyper” and reports that she often paces around her room. During this period, the patient has not slept. She had similar episodes 2 months and 5 months ago. The mother also states that, for the past 8 months, the patient has believed she is a famous singer and is going on a world tour next year. The patient does not have a partner and has only a few friends. She was working as a dental technician until 6 months ago, when she started to hear voices telling her to quit. She has not held a job since then. She does not use illicit drugs. Vital signs are within normal limits. Physical and neurological examinations show no abnormalities. On mental status examination, her speech is pressured, but she suddenly stops talking in the middle of sentences and does not finish them. She occasionally directs her attention to empty corners in the room, as if she were listening to someone. Which of the following is the most likely diagnosis?", "answer": "Schizoaffective disorder", "options": {"A": "Schizoaffective disorder", "B": "Schizotypal personality disorder", "C": "Schizophrenia", "D": "Delusional disorder", "E": "Mood disorder with psychotic features"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 4-year-old boy presents the pediatrician with his parents for a consultation after his school teacher complained about his abnormal behavior and his inability to make friends in school. They mention that the boy does not interact well with others at home, school, or daycare. On physical examination, his vital signs are stable with normal weight, height, and head circumference for his age and sex. His general examination and systemic examination, including neurologic examination, are completely normal. His recent audiologic evaluation shows normal hearing, and intellectual disability has been ruled out by a clinical psychologist. Which of the following investigations is indicated as part of his diagnostic evaluation at present?", "answer": "No further testing is needed", "options": {"A": "Magnetic Resonance Imaging (MRI) of brain", "B": "Positron Emission Tomography (SPECT) Scanning of head", "C": "Electroencephalography", "D": "Genetic testing for in MECP2 gene mutations", "E": "No further testing is needed"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 57-year-old man comes to the physician because of a 5-day history of fever, joint pain, malaise, and a diffuse rash. Two months ago, he was diagnosed with latent tuberculosis and the appropriate treatment was administered. Examination shows a scaly, maculopapular rash over the chest, arms, and back. Which of the following is the most likely explanation for this patient's current condition?", "answer": "Decreased acetyltransferase activity", "options": {"A": "Decreased pyridoxal kinase activity", "B": "Decreased acetaldehyde dehydrogenase activity", "C": "Decreased acetyltransferase activity", "D": "Decreased cytochrome p450 activity", "E": "Decreased glucose-6-phosphate dehydrogenase activity"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 40-hour-old baby girl is being evaluated for failure to pass meconium. She is the product of a full-term vaginal delivery to a G2P2 36-year-old mother. The pregnancy was uncomplicated, and the only medication that the mother took was a prenatal vitamin. The baby has been exclusively breastfed, and she has an adequate latch. On physical examination, the newborn’s abdomen is distended and on digital rectal examination, reveals that the rectum is empty. What is the most likely additional finding?", "answer": "Absence of ganglion cells in the submucosal plexus on suction biopsy of the rectum", "options": {"A": "Absence of ganglion cells in the submucosal plexus on suction biopsy of the rectum", "B": "Acid-producing mucosa visualized in a technetium scan", "C": "Presence of IgA anti-endomysial antibody", "D": "Abdominal ultrasound showing bowel-within-bowel", "E": "Inability to pass a 10-French catheter from the mouth into the stomach"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 65-year-old man presents to the physician with a low-grade fever, fatigue, and anorexia for the past 10 days. The patient denies any chest pain, cough, or shortness of breath. He has been a smoker for the last 10 years and consumes alcohol occasionally. His past medical history is significant for colorectal carcinoma. His temperature is 38.3°C (101.0°F), the blood pressure is 130/90 mm Hg, and the pulse is 100/min. Physical examination shows reddish-brown spots under his nail bed (as shown in the exhibit) and tender erythematous fingers tips. Cardiac auscultation reveals a new holosystolic murmur best heard at the apex with no radiation. Chest X-ray, electrocardiogram, and urinalysis are normal. Which of the following is the best next step in diagnosing this patient’s condition?", "answer": "Obtain blood samples for blood culture", "options": {"A": "Obtain anti-CCP antibody titers", "B": "Echocardiography", "C": "Obtain blood samples for blood culture", "D": "Initiate empiric antibiotics", "E": "Reassurance and symptomatic management"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 27-year-old man presents for followup 3 months after starting an antiretroviral regimen consisting of efavirenz, tenofovir, and emtricitabine. Labs drawn just prior to presentation reveal an undetectable viral load and a T-lymphocyte count of 317/mm^3. By comparison, his viral load was 6100/mL and his T-lymphocyte count was 146/mm^3 at the time of treatment initiation. He reports that he is tolerating the medications well and is not experiencing any major side effects. Which of the following treatment regimens should be recommended for this patient given the fully suppressed viral load?", "answer": "Continue current regimen of efavirenz, tenofovir, and emtricitabine", "options": {"A": "Continue current regimen of efavirenz, tenofovir, and emtricitabine", "B": "Continue efavirenz and emtricitabine but discontinue tenofovir", "C": "Continue efavirenz and tenofovir but discontinue emtricitabine", "D": "Continue tenofovir and emtricitabine but discontinue efavirenz", "E": "Discontinue efavirenz, tenofovir, and emtricitabine"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 60-year-old male painter with severe chest pain is found to have atherosclerosis of his coronary arteries. What type of cells were most likely injured in the initial stage of his disease?", "answer": "Endothelial cells", "options": {"A": "Myocytes", "B": "Fibroblasts", "C": "Neutrophils", "D": "Endothelial cells", "E": "Smooth muscle cells"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 27-year-old woman, gravida 1, at 26 weeks gestation presents to the physician during a prenatal visit. She feels well. Her pregnancy has been uncomplicated. Her initial laboratory tests at 8 weeks confirmed her blood type as B-. Her partner is blood type A+. At the clinic, her temperature is 37.2°C (99.0°F), and blood pressure is 108/60 mm Hg. Pelvic examination shows a uterus consistent in size with a 24-week gestation. Fetal heartbeats are normal. A sample of blood is collected for blood type screening and verification. Regarding Rh D immunoglobulin (RhoGam) administration, the most appropriate next step is which of the following?", "answer": "At 28 weeks gestation if anti-D screen is negative", "options": {"A": "At 28 weeks gestation if anti-D screen is negative", "B": "At 28 weeks gestation if anti-D screen is positive", "C": "Within 72 hours after birth if anti-D screen is negative", "D": "Within 72 hours after birth if anti-D screen is positive", "E": "Rh D immunoglobulin (RhoGam) is not required in this patient regardless of test results"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 32-year-old obese man visits your dermatology clinic after his barber saw a darkened area on the back of his neck. He has not seen his primary care physician in many years and does not know if he has diabetes. A rapid blood glucose test showed a normal glucose level. Otherwise, he reports recent loss of appetite with slight weight loss. What could be causing this patient’s newly-discovered dermatologic change?", "answer": "Gastric adenocarcinoma", "options": {"A": "Hypothyroidism", "B": "Gastric adenocarcinoma", "C": "Diabetes insipidus", "D": "Diabetes mellitus", "E": "Barrett’s esophagus"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 59-year-old man comes to the physician because of a 6-month history of progressive blurry vision in both eyes. His vision has not improved with the use of reading glasses. His blood pressure is 155/98 mm Hg. Physical examination shows his visual acuity to be 20/80 in the right eye and 20/60 in the left eye. A photograph of the fundoscopic examination of the right eye is shown. Which of the following is the most likely cause of this patient's symptoms?", "answer": "Diabetic retinopathy\n\"", "options": {"A": "Retinal detachment", "B": "Idiopathic intracranial hypertension", "C": "Open-angle glaucoma", "D": "Central retinal artery occlusion", "E": "Diabetic retinopathy\n\""}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 16-year-old high school cheerleader is brought by her mother to the emergency department after falling on her back during a stunt. She strongly believes that the accident happened because the team couldn’t catch her ‘enormous and bloated’ body. Lately, she has been in a lot of stress as dance regionals are coming up soon and she wants to lose 6.8 kg (15 lb). She is also experiencing intermittent palpitations and dizziness, even during rest. The physical examination reveals a slender girl with bilateral swelling on her cheeks and abrasions on the dorsum of her right hand. When her mother left the room, she admitted to taking furosemide that she found in the medicine cabinet. The vital signs include: temperature 36.2°C (97.2°F), blood pressure 90/60 mm Hg, pulse rate 50/min, respiratory rate 12/min, height 162 cm (5 ft 4 in), and weight 40.9 kg (90 lb). A magnetic resonance image (MRI) of the thoracic spine shows a vertebral compression fracture. She is refusing to eat anything but ice. What is the most appropriate next step in the management of this patient’s symptoms?", "answer": "Admit and start parenteral nutrition", "options": {"A": "Admit and start parenteral nutrition", "B": "Stabilize the fracture with a brace and discharge patient", "C": "Switch furosemide to hydrochlorothiazide", "D": "Start bisphosphonates", "E": "Refer to psychiatrist for outpatient cognitive behavioral therapy"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 44-year-old man presents to an oncologist after being diagnosed with small cell lung carcinoma confirmed with a biopsy last week. He worked as a plant technician in the metal processing unit at a factory for the last 14 years. Family history is unremarkable. It is concluded that this cancer is most likely mediated by mutations triggered by chronic chemical exposure at his work. Which of the following enzymes is primarily inhibited at the biochemical level by the chemical agent responsible for this patient’s condition?", "answer": "Pyruvate dehydrogenase", "options": {"A": "Pyruvate dehydrogenase", "B": "Phosphofructokinase", "C": "Dihydrofolate reductase", "D": "Glucose-6-phosphate dehydrogenase", "E": "Aconitase"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 41-year-old woman presents to the emergency room with a 2-day history of flank pain, nausea, and vomiting. She denies any urinary frequency or urgency and denies any recent changes in her diet. Her temperature is 100.4°F (38°C), blood pressure is 152/96 mmHg, and pulse is 104/min. On physical exam, there is bilateral flank tenderness to palpation. In addition, neurologic testing reveals decreased strength in her left upper extremity and an inability to sustain lateral gaze with her right eye. An electrocardiogram reveals an irregularly irregular heart rhythm. Which of the following is associated with the most likely cause of this patient's symptoms?", "answer": "Hereditary thrombophilia", "options": {"A": "Drug allergy", "B": "Hereditary thrombophilia", "C": "Hypertension", "D": "Placental abruption", "E": "Streptococcus infection"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 20-year-old African American woman comes to the clinic after missing her last two periods. Her cycles are usually regular, occurring at 28-32 day intervals with moderate bleeding and some abdominal discomfort. She also complains of occasional diffuse and generalized headaches. She is a college student and works part-time as a bartender. Past medical history is insignificant. Blood pressure is 110/70 mm Hg, pulse rate is 80 /min, respiratory rate is 14 /min, and temperature is 36.5°C (97.7°F). Physical examination is significant for mild breast tenderness and some secretions from the nipple area. Urine pregnancy test is negative. Which of the following is the best initial step in her management?", "answer": "Serum prolactin levels", "options": {"A": "MRI brain", "B": "Serum prolactin levels", "C": "LH/FSH ratio", "D": "Ultrasound of abdomen and pelvis", "E": "Dopamine agonists"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 25-year-old man comes to the physician because he and his wife have been unable to conceive a child despite having regular unprotected sexual intercourse. He is 187 cm (6 ft 1 in) tall and weighs 79 kg (174 lb). Examination shows long extremities, bilateral gynecomastia, and small, firm testes. A peripheral blood smear shows a dense, dark-staining spot at the periphery of the nucleus of a cell. Which of the following is the most likely explanation for the finding on this patient's peripheral blood smear?", "answer": "Methylation of cytosine nucleotides", "options": {"A": "Acetylation of histone lysine residues", "B": "Impaired removal of RBC nuclei remnants", "C": "Methylation of cytosine nucleotides", "D": "Aggregation of ribosomes", "E": "Precipitation of oxidized hemoglobin"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 22-year-old woman college student presents with diarrhea and crampy abdominal pain that is relieved by defecation. She states that she has had a lot of ‘stomach issues’ in the past, especially during exam weeks. The past medical history is significant for major depressive disorder diagnosed 2 years ago that has been managed with Prozac. She does not have a family history of irritable bowel disease, autoimmune disease, or cancer. The symptoms do not seem to be worse with any particular food, though she admits to eating a lot of pizza and deli sandwiches with minimal fruits and vegetables. She denies recent travel and has not experienced fever, weight loss, nausea, or vomiting. She has not noticed blood in her stool. The physical exam and laboratory findings are unremarkable. Which of the following is a diagnostic criteria for the disorder that is most likely responsible for the patient’s presentation?", "answer": "Symptoms present at least 1 day per week for 3 consecutive months with symptom onset at least 6 months before diagnosis", "options": {"A": "Symptoms present at least 6 months", "B": "Symptoms not relieved with defecation", "C": "No change in stool frequency", "D": "Symptoms present at least 1 day per week for 3 consecutive months with symptom onset at least 6 months before diagnosis", "E": "No change in stool consistency"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 69-year-old female presents to the emergency department with crampy abdominal pain. She has a past medical history of hypertension, dyslipidemia, and cholelithiasis status post cholecystectomy. The patient states she has not passed stool or gas for 48 hrs. On physical exam vitals are T 98.4 F HR 105 bpm BP 155/101 mmHg RR 16 SpO2 96%, abdominal exam is notable for distension, tympany to percussion, and tenderness to palpation without rebound or guarding. Which of the following findings are most likely on radiograph?", "answer": "Ladder-like series of distended bowel loops with air-fluid levels on abdominal radiograph", "options": {"A": "Free air under the diaphragm on upright abdominal radiograph", "B": "Apple core defect after lower GI series", "C": "Multiple punctate mucosal outpouchings through the serosa on lower GI series", "D": "Ladder-like series of distended bowel loops with air-fluid levels on abdominal radiograph", "E": "Loss of haustral markings and \"lead pipe\" appearance to the descending colon on lower GI series"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 56-year-old man comes to the physician because of a 2-month history of worsening pain in his left buttock. The pain is described as a deep, dull ache that is worse at night. He does not report any recent trauma. He has hyperlipidemia. He has smoked one pack of cigarettes daily for the past 30 years and drinks one beer every night. He does not use illicit drugs. His only medication is simvastatin. Physical examination shows tenderness over the left gluteal region. Neurologic examination shows no focal findings. An x-ray of the pelvis shows a 4-cm, poorly defined, osteolytic lesion in the left ilium with a moth-eaten pattern of bone destruction, multiple well-defined sclerotic lesions, and an aggressive periosteal reaction. The remainder of the physical examination, including rectal examination, shows no abnormalities. Chest x-ray and abdominal ultrasonography show no abnormalities. Which of the following is the most likely diagnosis?", "answer": "Chondrosarcoma", "options": {"A": "Giant cell tumor", "B": "Fibrosarcoma", "C": "Plasmacytoma", "D": "Osteochondroma", "E": "Chondrosarcoma"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "An otherwise healthy 49-year-old man comes to the physician because of a 1-month history of worsening headaches and increasing irritability. Examination shows bilateral papilledema. An MRI of the brain shows a mass in the right temporal lobe with heterogeneous peripheral rim enhancement that crosses the midline. He undergoes surgical resection of the mass. Gross examination shows a poorly-demarcated mass with areas of hemorrhage and necrosis. Microscopic examination of the mass will most likely show which of the following?", "answer": "Pleomorphic cells forming pseudopalisades", "options": {"A": "Closely-packed capillaries and foamy stromal cells", "B": "Pleomorphic cells forming pseudopalisades", "C": "Cells with clear cytoplasm and central round nuclei", "D": "Small blue cells arranged in rosettes", "E": "Areas of lamellated calcification"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A male newborn develops hyperammonemia, encephalopathy, and respiratory alkalosis 3 days after a normal delivery. He enters into a coma the next day and dies a week later. Family history is positive for parental consanguinity. Histopathologic examination of the liver shows diffuse microvesicular steatosis, distinct focal hepatocellular fibrosis, and Kupffer cell glycogenosis. Citrulline levels are low. What enzyme is most likely deficient in this patient’s case?", "answer": "Carbamoyl phosphate synthetase I", "options": {"A": "Carbamoyl phosphate synthetase I", "B": "Cystathionine synthase deficiency", "C": "Homogentisic acid dioxygenase", "D": "Ornithine transcarbamylase", "E": "Propionyl-CoA carboxylase"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 48-year-old woman is brought to the emergency department immediately following a motor vehicle accident in an unconscious state. She is managed as per emergency treatment protocols with the airway, breathing, and circulation being appropriately managed by mechanical ventilation, intravenous fluids, and other supportive drugs. A complete diagnostic evaluation suggests a diagnosis of traumatic brain injury and rules out the presence of fractures and other visceral injuries. About 36 hours after the accident, pulse oximetry shows deteriorating oxygen saturation. Chest auscultation reveals widespread rales over bilateral lung fields. Her arterial blood gas analysis shows a PaO2 of 100 mm Hg at FiO2 of 60%. Her bedside echocardiogram is normal and suggests a pulmonary capillary wedge pressure of 11 mm Hg. Which of the following signs is most likely to be present in her chest radiogram?", "answer": "Bilateral asymmetric pulmonary infiltrates with peripheral distribution", "options": {"A": "Deep sulcus sign with radiolucency along the costophrenic sulcus", "B": "Lung collapse at the hilum on one side and shift of the mediastinum to the opposite side", "C": "Bilateral asymmetric pulmonary infiltrates with peripheral distribution", "D": "Increased size of cardiac silhouette and cephalization of pulmonary vessels", "E": "Abrupt tapering of a pulmonary artery"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 58-year-old man with a history of heart failure is admitted to the hospital for a cardiac transplantation. Five years ago, the patient had a mitral valve replacement with a porcine valve, but since then his heart failure symptoms have not improved. He developed persistent New York Heart Association class IV symptoms and was placed on the transplant waiting list. The heart to be transplanted originated from a deceased donor and the family has given consent for the transplantation. The patient is subsequently started on cyclosporine, and the postoperative period is unremarkable. He is readmitted to the emergency department 10 months later due to chest pain and severe shortness of breath. What is true about the medication prescribed to this patient?", "answer": "Inhibits calcineurin", "options": {"A": "Inhibits IMP dehydrogenase", "B": "Binds FK506 binding protein", "C": "Blocks IL-2R", "D": "Inhibits calcineurin", "E": "Is a precursor of 6-mercaptopurine"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "An investigator studying renal physiology uses para-aminohippuric acid (PAH) to estimate the renal plasma flow in a human volunteer. An intravenous infusion of 400 mg of PAH solution is administered to the subject; effective renal plasma flow is calculated to be 600 ml/min. Next, an intravenous infusion of 1000 mg of PAH solution is administered to the subject; effective renal plasma flow is calculated to be 400 mL/min. Which of the following explains the measured decline in the calculated effective renal plasma flow?", "answer": "Decreased PAH clearance", "options": {"A": "Decreased serum protein binding", "B": "Increased plasma oncotic pressure", "C": "Efferent arteriole dilation", "D": "Afferent arteriole dilation", "E": "Decreased PAH clearance"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 55-year-old man presents to his primary care physician with a 2-month history of fatigue. He says that he has been feeling tired, even after mild exertion, and decided to be evaluated because it has begun interfering with his job as a construction worker. He reports that he has been feeling numbness and tingling in his feet and has been tripping more frequently. His past medical history is significant for hypertension and type 2 diabetes well-controlled on metformin. His surgical history is significant for weight-loss surgery 2 years ago. Physical exam reveals bilateral vibration sensory deficits as well as conjunctival pallor. Selected lab results are presented as follows:\n\nHemoglobin: 9.1 g/dL\nHematocrit: 27%\nPlatelet count: 265,000/mm^3\nMean corpuscular volume: 112 µm^3\nReticulocyte count: 0.19%\n\nWhich of the following findings would most likely also be seen in this patient?", "answer": "High methylmalonic acid and high homocysteine levels", "options": {"A": "Elevated bilirubin levels", "B": "High methylmalonic acid and high homocysteine levels", "C": "High transferrin levels", "D": "Low haptoglobin levels", "E": "Normal methylmalonic acid and high homocysteine levels"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 27-year-old woman is brought to the emergency department by her coworker after having a generalized seizure at work. Her coworker reports that she is at 30 weeks' gestation and has mentioned headache and right upper quadrant pain earlier that day. Her temperature is 37°C (98.6°F), pulse is 91/min, and blood pressure is 170/102 mm Hg. Pulmonary examination shows bilateral rales. There is diffuse edema in the lower extremities. Deep tendon reflexes are increased bilaterally. She is not oriented to person, place, and time. Which of the following is the most appropriate initial pharmacotherapy?", "answer": "Magnesium sulfate", "options": {"A": "Calcium gluconate", "B": "Aspirin", "C": "Phenytoin", "D": "Lorazepam", "E": "Magnesium sulfate"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 23-year-old woman presents to the emergency department because of nausea. She has been experiencing severe intermittent nausea and diarrhea for the last year and refuses to leave the emergency department until she is told what is causing her symptoms. She hates hospitals but has reluctantly undergone numerous workups and imaging studies in order to discern what is wrong. All of the studies have been normal. She says that these symptoms have been causing her severe distress and is impairing her ability to perform her job. She says that she feels as if the nausea is worse when she is trying to work but says that she will continue to work as an insurance agent despite the physical discomfort. She has started restricting her diet to only graham crackers because she thinks that helps her symptoms. She has also started avoiding eating lunch because of the nausea. Which of the following disorders is most consistent with this patient's presentation?", "answer": "Somatic symptom disorder", "options": {"A": "Conversion disorder", "B": "Factitious disorder", "C": "Illness anxiety disorder", "D": "Malingering", "E": "Somatic symptom disorder"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 37-year-old homeless man is brought in by ambulance to the emergency department after being found unresponsive. He was found in an area of IV drug use with drug paraphernalia including glassine envelopes with a white powder residue. There is no past medical history available. He is treated with intranasal naloxone and stabilized in the field. Upon arrival to the hospital, his blood pressure is 100/70 mm Hg, pulse rate is 90/min, respiratory rate is 18/min, and temperature is 38.9°C (102.0°F). On physical examination, the patient is jaundiced with white scrapable exudates on the oral mucosa. His arms are covered with stigmata of IV drug use. Heart auscultation reveals a holosystolic murmur that is loudest at the left sternal border. The lungs are clear to auscultation bilaterally. Laboratory work is performed which shows:\nHemoglobin 10.9 g/dL\nHematocrit 37.7%\nLeukocyte count 1,500/mm3\nNeutrophils 65%\nLymphocytes 30%\nMonocytes 5%\nMean corpuscular volume 82.2 μm3\nPlatelet count 190,000/mm3\nErythrocyte sedimentation rate 35 mm/h\nAspartate aminotransferase 2,400 U/L\nAlanine aminotransferase 3,200 U/L\nCD4 count 27 cells/mm3\nHIV-1 antibody positive\nHepatitis C virus antibody positive\nQuantiferon-gold test negative\nWhich of the laboratory findings will be found in this patient?", "answer": "Positive blood culture", "options": {"A": "Atypical lymphocytes on blood smear", "B": "Positive blood culture", "C": "Elevated antistreptolysin O (ASO) titer", "D": "Elevated levels of cardiac troponin I and T", "E": "Positive sputum culture"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 35-year-old woman, gravida 6, para 5, at 35 weeks' gestation comes to the emergency department because of vaginal bleeding for 2 hours. This is her second episode in the past 2 days. She has had no prenatal care. Her children were delivered vaginally. Her pulse is 122/min, respirations are 20/min, and blood pressure is 88/59 mm Hg. The abdomen is nontender, and no contractions are felt. There is active bright red vaginal bleeding. The fetal heart rate is 110/min. Two large-bore peripheral intravenous cannulas are inserted and intravenous fluids are administered. Three units of blood are typed and cross-matched. Which of the following is the most appropriate step in management?", "answer": "Perform cesarean delivery", "options": {"A": "Perform cesarean delivery", "B": "Hospitalization and observation", "C": "Administer magnesium sulfate", "D": "Induce labor", "E": "Perform cervical cerclage"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 2710-g (6-lb) male newborn is delivered at 38 weeks of gestation to a 26-year-old woman, gravida 2, para 2. The pregnancy, labor, and delivery were uncomplicated. Breastfeeding is initiated. Which of the following supplements is most important to prevent a potentially life-threatening condition in this newborn?", "answer": "Vitamin K", "options": {"A": "Vitamin B1", "B": "Vitamin K", "C": "Folic acid", "D": "Iron", "E": "Vitamin D"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 4-month-old adopted infant is brought to the pediatrician because of feeding problems and recurrent fungal and bacterial infections. Her family has almost no background information about the infant. They report that she is a little fragile and looks different compared to other infants her age. Physical evaluation reveals a cleft lip with intact hard and soft palate and mild jaw malformation. An echocardiogram reveals an interrupted aortic arch. Further investigation reveals leukopenia and mild hypocalcemia. These findings support a diagnosis of which of the following?", "answer": "DiGeorge syndrome", "options": {"A": "Chediak-Higashi syndrome", "B": "DiGeorge syndrome", "C": "Severe combined immunodeficiency (SCID)", "D": "Adenosine deaminase (ADA) deficiency", "E": "Wiskott-Aidrich syndrome"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 48-year-old homeless man presents to clinic complaining of fatigue and fevers that \"began recently.\" Cardiac exam reveals a holosystolic murmur, heard best over the left lower sternal border. The murmur increases on inspiration. He also has track marks on his arms bilaterally. This presentation is consistent with which defect?", "answer": "Tricuspid regurgitation", "options": {"A": "Ventricular septal defect", "B": "Tricuspid regurgitation", "C": "Mitral regurgitation", "D": "Aortic stenosis", "E": "Pulmonary stenosis"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 65-year-old diabetic man presents to the emergency department with severe retrosternal chest pain, vomiting, and diaphoresis for the last half hour. He has a history of diabetic chronic kidney disease. He is on insulin therapy. Oral medications include aspirin, losartan, and metformin. The vital signs include: temperature 36.8°C (98.2°F), pulse 88/min, respiration rate 14/min, and blood pressure 120/65 mm Hg. The weight is 78 kg (172.0 lb). The lungs are clear to auscultation. Cardiac examination shows no abnormalities. The electrocardiogram (ECG) shows ST-segment elevation in the precordial leads V-1–V-4. Left ventricular ejection fraction is estimated at 55%. The laboratory test results are as follows:\nLaboratory test\nHemoglobin 15 g/dL\nLeukocyte count 9,500/mm3\nSerum\nGlucose 215 mg/dL\nNa+ 140 mEq/L\nCl− 102 mEq/L\nK+ 4.1 mEq/L\nUrea nitrogen 22 mg/dL\nCreatinine 1.4 mg/dL\nCardiac troponin I 0.8 ng/mL\nThe patient is being considered for primary percutaneous coronary intervention. Which of the following management steps is most likely to decrease the risk for development of acute renal failure in this patient?", "answer": "Intravenous normal saline", "options": {"A": "Intravenous furosemide", "B": "Intravenous normal saline", "C": "Reduced intravenous contrast dose", "D": "Preemptive hemodialysis", "E": "Withholding losartan"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 7-year-old boy is brought in to your clinic by his mother, who is complaining of her son’s “dry scalp and hair loss.” She reports a scaling spot on his scalp developed around 2 months ago, soon after moving to a new school, which then became a larger bald spot. She denies that anyone in the household is exhibiting similar symptoms, but does recall a note that came home from school warning of a lice outbreak. Thus far, she has only tried daily baths with little improvement. The patient denies pain or itchiness, but the mother reports she does notice him scratching his scalp. The mother also reports that since her son has started at the new school, she has noticed an increase in his tics including excessive blinking and clearing of his throat. The patient's medical history is significant for asthma, allergic rhinitis, and attention deficient hyperactivity disorder. His current medications include fluticasone, salmeterol, loratadine, and methylphenidate. Family history includes obsessive compulsive disorder in his older sister. The mother also reports her father had a debilitating skin and joint disorder. On examination, you note swollen lymph glands at the back of the patient's ears and neck, and there are residual black dots within a patch of alopecia. Which of the following is the most likely diagnosis?", "answer": "Tinea capitis", "options": {"A": "Nummular dermatitis", "B": "Psoriasis", "C": "Tinea capitis", "D": "Pediculosis capitis", "E": "Trichotillomania"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 68-year-old man is brought to the emergency department because of a 1-day history of fever and cloudy urine. He lives in a group home and has a chronic indwelling urinary catheter for benign prostatic hyperplasia. He has depression, for which he takes vilazodone. His temperature is 38.3°C (100.9°F), pulse is 89/min, and blood pressure is 110/74 mm Hg. Urine cultures grow Enterococcus faecium resistant to vancomycin, and therapy with intravenous linezolid is initiated. Eight hours later, he becomes agitated and starts to sweat profusely. His temperature is 39.6°C (103.3°F), pulse is 120/min, and blood pressure is 184/105 mm Hg. Neurologic examination shows increased deep tendon reflexes and clonus of the arms and legs. In addition to discontinuation of his current medication, administration of which of the following drugs is most appropriate in this patient?", "answer": "Cyproheptadine", "options": {"A": "Flumazenil", "B": "Dantrolene", "C": "Octreotide", "D": "Cyproheptadine", "E": "Benztropine\n\""}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 54-year-old man is newly diagnosed with diabetes. As part of his clinical care, he undergoes testing to determine his kidney function. His glomerular filtration rate is found to be 80 mL/min. He is curious about how glomerular filtration occurs and which molecules are filtered the fastest and slowest. He is told that albumin is filtered less readily than sodium. Aside from size of the 2 molecules, which of the following features of the glomerular basement membrane accounts for this additional finding?", "answer": "Negative charge", "options": {"A": "Thickness", "B": "Positive charge", "C": "Negative charge", "D": "Fenestrations", "E": "Presence of podocytes"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 2-year-old boy with recurrent ear infections is brought to the pediatrician for a follow-up examination. He can walk with support and his vocabulary consists of approximately 50 words. His maternal uncle died in childhood from an unknown disease. Physical examination shows coarse facial features with an enlarged tongue. The abdomen is distended and both the liver and spleen tip are palpable. Laboratory studies show elevated total urinary glycosaminoglycan levels and an absence of plasma iduronate-2-sulfatase. Which of the following additional findings is most likely in this patient?", "answer": "Aggressive behavior", "options": {"A": "Optic atrophy", "B": "Leukopenia and thrombocytopenia", "C": "Cherry-red macula", "D": "Corneal clouding", "E": "Aggressive behavior"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 29-year-old woman presents to a physician at 16 weeks gestation with fevers and a cough for 2 days. The cough is productive and occurs more often in the morning. Her medical history is not significant. Physical and laboratory evaluations suggest a diagnosis of community-acquired pneumonia. The physician explains to her that she needs to be treated with antibiotic therapy. She asks the physician if she can take levofloxacin because she tolerates levofloxacin. The physician explains that levofloxacin should be avoided during pregnancy because fetal exposure may increase the risk of a specific medical condition. Which of the following medical conditions is the physician referring to?", "answer": "Arthropathy", "options": {"A": "Arthropathy", "B": "Congenital heart defect", "C": "Deafness", "D": "Neural tube defect", "E": "Ocular anomalies"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A large, multicenter study is conducted to assess the prevalence and mortality rate of pneumonia requiring hospitalization caused by various pathogens in 3 states over the past year. The study encompassed 250,000 adults between 45–79 years of age. The results for five different pathogens are shown:\nAll cases Fatal cases\nPathogen Number Percentage Number Percentage\nS. aureus 460 34.8 69 50.3\nInfluenza virus 288 21.8 12 8.8\nP. aeruginosa 136 10.3 17 12.4\nS. pneumoniae 338 25.5 27 19.7\nKlebsiella spp. 101 7.6 12 8.8\nTotal 1323 100 137 100\nA journalist would like to report the yearly case fatality rate of the pneumonia pathogen responsible for most hospitalizations in these states. Based on the study results, which of the following responses by the investigator is most accurate?\"", "answer": "15.0%", "options": {"A": "10.4%", "B": "50.3%", "C": "34.8%", "D": "15.0%", "E": "12.5%"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 52-year-old woman is admitted to the surgical unit after a laparoscopic hysterectomy for uterine leiomyomas performed 2 days ago. The surgery was performed under general anesthesia, blood loss was minimal, and there were no intraoperative complications. The patient reports lower abdominal pain and discomfort. Medical history is significant for multiple sclerosis that is well-controlled with ocrelizumab. Her last multiple sclerosis flare was approximately 7 years ago and presented with paresthesias and weakness of the upper extremities. Her temperature is 99°F (37.2 °C), blood pressure is 125/85 mmHg, pulse is 99/min, and respirations are 19/min. On physical exam, the patient appears restless and uncomfortable. The surgical incision sites are mildly erythematous and without discharge. There is tenderness with deep suprapubic palpation. Neurologic exam is unremarkable. Laboratory studies show:\n\nSerum:\nNa+: 144 mEq/L\nCl-: 100 mEq/L\nK+: 4.3 mEq/L\nHCO3-: 26 mEq/L\nGlucose: 105 mg/dL\nCreatinine: 3.1 mg/dL\n\nWhich of the following is the best next step in management?", "answer": "Bladder scan", "options": {"A": "Bethanechol administration", "B": "Bladder scan", "C": "Intravenous fluids", "D": "Urine studies", "E": "Urodynamic studies"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 38-year-old female visits your office complaining of several years of joint swelling and stiffness that is worse in the morning and improves throughout the day. Physical examination reveals bilateral deformities at her proximal interphalangeal and metacarpophalangeal joints. The presence of which of the following in this patient’s serum would most help 'rule in' a diagnosis of rheumatoid arthritis:", "answer": "Anti-citrullinated protein antibody", "options": {"A": "Rheumatoid factor", "B": "Anti-nuclear antibody", "C": "Anti-citrullinated protein antibody", "D": "Anti-centromere antibody", "E": "Anti-smooth muscle antibody"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 3-week-old infant presents to the emergency department with thick white discharge from his eyes that has persisted for the past 24 hours. The patient's birth was not complicated, and he was born at home vaginally with a mid-wife supervising the birth. The patient has a documented allergy to penicillin which caused anaphylaxis after it was given secondary to a maternal syphilis infection. His temperature is 97.6°F (36.4°C), blood pressure is 75/40 mm Hg, pulse is 130/min, respiratory rate is 24/min, and oxygen saturation is 98% on room air. The patient is currently sleeping. Physical exam is notable for bilateral purulent drainage from the eyes. Which of the following is a complication associated with the best treatment for this patient?", "answer": "Non-bilious projectile vomiting", "options": {"A": "Damage to the lacrimal ducts", "B": "Non-bilious projectile vomiting", "C": "Optimal therapy has no known side-effects", "D": "Possible anaphylaxis and urticaria", "E": "Sedation and increased sleepiness"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 10-year-old boy initially presented with a runny nose, fever, and watery eyes. His parents gave him aspirin. Over the next few days, the boy developed jaundice, became irritable, lethargic, and had seizures. The hepatic transaminases were significantly raised. The blood ammonia levels were also increased. A liver biopsy is performed. Which of the following histopathological findings will most likely be seen on the liver biopsy in this patient?", "answer": "Cytoplasmic fatty vacuolization in hepatocytes and swollen mitochondria", "options": {"A": "Hepatic granulomas", "B": "Iron accumulation and proliferation of smooth endoplasmic reticulum", "C": "Hepatocytes proliferation", "D": "Cytoplasmic fatty vacuolization in hepatocytes and swollen mitochondria", "E": "Bridging hepatic necrosis and fibrosis"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "An 18-year-old woman presents with a dry cough for the past 2 weeks. She also says that she is tired all the time and feels feverish and chilly at times. She is a college student and lives in a dormitory and says that her roommate has a similar cough. Past medical history is unremarkable. The patient denies any smoking history, alcohol or recreational drug use. Her vitals signs include: temperature 36.8°C (98.2°F), pulse 72/min, blood pressure 118/63 mm Hg, and respiratory rate 15/min. Physical examination is unremarkable. A chest radiograph reveals interstitial infiltrates that look worse than her symptoms. A nasopharyngeal swab is sent to the lab for a bacterial culture which shows colonies having fried-egg appearance on Eaton’s agar. Cold agglutinins are positive. Which of the following antibiotics would be best to administer to this patient?", "answer": "Erythromycin", "options": {"A": "Vancomycin", "B": "Penicillin", "C": "Ceftriaxone", "D": "Erythromycin", "E": "Aztreonam"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 9-year-old boy comes to the physician because of pain with swallowing and a burning sensation in his mouth for the past 10 days. Over the past 3 weeks, he has had increasing fatigue and runs out of breath easily. His father had gallstones, for which he underwent a cholecystectomy at the age of 30 years. The boy appears weak and lethargic. His temperature is 37.7°C (99.8°F), blood pressure is 110/68 mm Hg, pulse is 105/min, and respirations are 28/min. Examination shows pallor of the mucosal membranes, mild scleral icterus, and a swollen, red tongue. His spleen is enlarged and palpable 2–3 cm below the left costal margin. A complete blood cell count shows a hemoglobin concentration of 9.8 g/dL, mean corpuscular volume of 102 μm3, and a reticulocyte count of 0.4%. His peripheral blood smear shows erythrocytes without central pallor. Which of the following could have prevented this patient's chief complaints?", "answer": "Folic acid supplementation", "options": {"A": "Folic acid supplementation", "B": "Cholecystectomy", "C": "Gluten-free diet", "D": "Vaccination against pneumococci", "E": "Vitamin B12 injections"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 62-year-old man is brought to the hospital because of a 6-hour history of worsening upper abdominal pain, nausea, and vomiting. He is diagnosed with acute calculous cholecystitis and scheduled for cholecystectomy the next day. He has congestive heart failure, hyperlipidemia, and hypertension. Physical examination shows no abnormalities. Current medications include metoprolol and simvastatin. One month ago, spironolactone was added to his medication regimen. Preoperative serum studies show:\nNa+ 138 mEq/L\nK+ 6.1 mEq/L\nCl- 100 mEq/L\nHCO3- 22 mEq/L\nUrea nitrogen 13 mg/dL\nCreatinine 1.0 mg/dL\nAn ECG shows normal sinus rhythm. In addition to discontinuation of spironolactone, which of the following is the most appropriate next step in management of this patient's hyperkalemia?\"", "answer": "Administer intravenous saline with furosemide", "options": {"A": "Administer intravenous saline with furosemide", "B": "Administer intravenous sodium bicarbonate", "C": "Order dietary modification", "D": "Administer intravenous calcium gluconate", "E": "Initiate hemodialysis"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 48-year-old woman comes to the physician for a follow-up examination. She has a history of type 2 diabetes mellitus and coronary artery disease. Current medications include metformin, aspirin, pravastatin, and losartan. Her body mass index is 30 kg/m2. Physical examination shows no abnormalities. Her hemoglobin A1c concentration is 8%. She does not want to start insulin injection therapy and is afraid that a new medication is going to cause weight gain. Empagliflozin is added to her diabetes regimen. This patient is at greatest risk for which of the following adverse effects of this new drug?", "answer": "Vaginal candidiasis", "options": {"A": "Localized lipodystrophy", "B": "Vaginal candidiasis", "C": "Hypoglycemia", "D": "Agranulocytosis", "E": "Lactic acidosis"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 62-year-old man with coronary artery disease and type 2 diabetes mellitus comes to the emergency department because of frequent episodes of palpitations for 4 days. His pulse is 165/min and blood pressure is 98/70 mm Hg. An ECG shows monomorphic ventricular tachycardia. Intravenous pharmacotherapy is begun with a highly lipophilic drug that prolongs the duration of the myocardial action potential and refractory period and inhibits adrenergic stimulation of the myocardium. The patient's ventricular tachycardia converts to normal sinus rhythm. He is discharged home with an oral formulation of the same drug. Which of the following adverse effects is most commonly associated with long-term use of this medication?", "answer": "Hyperthyroidism", "options": {"A": "Priapism", "B": "Acne vulgaris", "C": "Angle-closure glaucoma", "D": "Hyperthyroidism", "E": "Hepatic adenoma"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 45-year-old woman presents to her primary care physician complaining of weight gain. She states that for the past few months she has gained 10 pounds, especially around her abdomen. She says that this is despite going to kickboxing classes 5 days a week. She reports mild fatigue and muscle soreness, which she attributes to her exercise classes. She also complains of dry skin and hair, but feels that this might be due to showering twice a day. Her medical history is significant for major depressive disorder. She takes citalopram and a multivitamin. She smokes a half pack of cigarettes a day. She drinks 1 glass of red wine every night after dinner, and 3-4 drinks mixed with hard liquor on the weekend with friends. Her temperature is 98°F (36.7°C), blood pressure is 122/75, and pulse is 65/min. Her physical examination is unremarkable, except for xerosis. Labs are obtained, as shown below:\n\nSerum:\nNa+: 130 mEq/L\nK+: 4.1 mEq/L\nCl-: 101 mEq/L\nBUN: 16 mg/dL\nGlucose: 125 mg/dL\nCreatinine: 0.9 mg/dL\nAspartate aminotransferase (AST): 56 U/L\nAlanine aminotransferase (ALT): 70 U/L\nCreatine kinase (CK): 223 U/L (normal 22 to 198 U/L)\n\nHemoglobin A1c: 5.3\nTotal cholesterol: 264 mg/dL (normal < 200 mg/dL)\nLow-density lipoprotein (LDL) cholesterol: 117 mg/dL (normal < 100 mg/dL)\nHigh-density lipoprotein (HDL) cholesterol: 48 (normal > 50 mg/dL)\nTriglycerides: 163 mg/dL (normal < 150 mg/dL)\n\nWhich of the following is the most appropriate next step in management?", "answer": "Thyroxine", "options": {"A": "Fludrocortisone", "B": "Liver biopsy", "C": "Muscle biopsy", "D": "Simvastatin", "E": "Thyroxine"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 31-year-old woman comes to the physician because of white lesions in her mouth that she first noticed 5 days ago. The lesions are not painful or itchy. She has asthma treated with theophylline, inhaled β-adrenergic agonists, and corticosteroids. She smokes half a pack of cigarettes daily. She appears healthy. Vital signs are within normal limits. Oral examination shows white plaques on the buccal mucosa and hard palate that are firmly adherent and cannot be scraped off. She has no cervical or axillary lymphadenopathy. Which of the following is the most appropriate next step in the management of this patient?", "answer": "Biopsy of the lesions", "options": {"A": "Topical nystatin", "B": "Biopsy of the lesions", "C": "Smoking cessation", "D": "Culture of the lesions", "E": "Monospot test"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "An 11-year-old male is brought to his pediatrician for continuing management of a chronic lung infection. He has had many lung infections throughout childhood, and current sputum samples show oxidase positive, non-lactose fermenting gram-negative rods that produce a blue-green pigment. Physical exam shows nasal polyps and nail clubbing. He has also recently been experiencing floating foul smelling diarrhea, so he is prescribed enzymes and vitamin supplementation tablets. Which of the following chromosomes most likely contains the gene mutation responsible for this patient's symptoms?", "answer": "7", "options": {"A": "7", "B": "11", "C": "17", "D": "22", "E": "X"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 16-year-old girl is brought to the physician for a routine health maintenance examination. Her last visit was over a year ago. Menarche was at the age of 12 years; her last menstrual period was 4 months ago. She is on the school's gymnastics team and is currently preparing for an important competition. She is 165 cm (5 ft 5 in) tall and weighs 45 kg (99 lbs); BMI is 16.5 kg/m2. Her temperature is 36.8°C (98.2°F), pulse is 53/min, and blood pressure is 98/64 mm Hg. Examination shows yellowish discoloration of the skin. There are bilateral soft symmetric masses below her mandible. The skin over the dorsal side of her right hand is thickened. The patient is most likely to develop which of the following complications?", "answer": "Fractures", "options": {"A": "Recurrent infections", "B": "Ovarian cancer", "C": "Hyperkalemia", "D": "Fractures", "E": "Hyperthyroidism"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 32-year-old female is seeing an endocrinologist for the first time after a recently-diagnosed illness by her primary care physician. Her temperature is 99.7 °F (37.6 °C), blood pressure is 110/65 mmHg, pulse is 89/min, and respirations are 11/min. Prior to starting medical management, the patient is cautioned to alert her providers if she becomes pregnant, as this medication crosses the placenta and is known to cause aplasia cutis. Which of the following activities is inhibited by this medication?", "answer": "Coupling of iodine with tyrosine residues", "options": {"A": "Conversion of T4 to T3", "B": "Coupling of iodine with tyrosine residues", "C": "Production of TRH", "D": "Response of peripheral tissues to thyroid hormone", "E": "Sensitivity of anterior pituitary to TRH"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 62 year old woman presents to her doctor complaining of painful tingling and burning in her feet for the past year. Careful physical exam demonstrates that she has poor position sense in her bilateral lower extremities. Lab results reveal elevated urine and plasma methylmalonic acid concentrations. What vitamin deficiency is this woman most likely suffering from?", "answer": "Vitamin B12", "options": {"A": "Vitamin C", "B": "Vitamin B1", "C": "Vitamin B12", "D": "Biotin", "E": "Folic acid"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 52-year-old man visits his psychiatrist saying he feels sad most of the time. 5 months ago, he lost his daughter in a motor vehicle accident and since then has been unable to cope with this loss. He spends most of his day thinking about her and this often distracts him from his daily activities. He also admits to hearing his daughter’s voice in his sleep and sometimes has dreams about her. During the day, he sometimes gets brief glimpses of her. He believes this is because he was not able to do anything to help her during the last moments of her life. Other than this, he is able to get along his daily life and has never contemplated suicide. But he often wishes he could be close to his daughter again. Which of the following best describes the symptoms this patient is expressing?", "answer": "Normal grief reaction", "options": {"A": "Brief psychotic disorder", "B": "Major depressive disorder", "C": "Normal grief reaction", "D": "Post-traumatic stress disorder", "E": "Morbid grief reaction"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 68-year-old woman with hypertension and congestive heart failure is brought to the emergency department because of a 2-day history of shortness of breath and confusion. Her pulse is 112/min, respirations are 22/min, and blood pressure is 73/45 mm Hg. Examination shows cool extremities, jugular venous distention, and diffuse crackles in the lungs. Treatment with intravenous dobutamine is begun. Which of the following is the primary mechanism of action of this drug?", "answer": "β1-adrenergic agonism", "options": {"A": "α2-adrenergic agonism", "B": "β2-adrenergic antagonism", "C": "β1-adrenergic agonism", "D": "α1-adrenergic antagonism", "E": "D1 agonism"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 58-year-old man comes to the physician for a follow-up examination dressed in a vampire costume. He is on his way to a Halloween party at an assisted-living facility, where he works as a patient care attendant. He feels well. He has a history of hypertension that is well controlled. He was also diagnosed with type 2 diabetes two months ago during a routine check up. His current medications include lisinopril and metformin. His father died of colon cancer at 52 years of age. His screening colonoscopy at age 55 was normal. He used to smoke half a pack of cigarettes daily for 10 years but quit 15 years ago. His temperature is 37°C (98.6°F), pulse is 90/min, respirations are 14/min, and blood pressure is 138/90 mm Hg. Physical examination shows no abnormalities. His hemoglobin A1c two months ago was 7.6%. Which of the following health maintenance recommendations is most appropriate at this time?", "answer": "Influenza vaccine", "options": {"A": "Hemoglobin A1c measurement", "B": "Influenza vaccine", "C": "Prostate-specific antigen measurement", "D": "Colonoscopy", "E": "Low-dose CT scan"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 33-year-old homeless man presents to the emergency department with an altered mental status. The patient was found minimally responsive at a local mall and was brought in by police. The patient has a past medical history of polysubstance abuse, anxiety, depression, and panic disorder. His current medications include sertraline, clonazepam, and amitriptyline. His temperature is 98.7°F (37.1°C), blood pressure is 117/68 mmHg, pulse is 80/min, respirations are 10/min, and oxygen saturation is 98% on room air. Physical exam is notable for a somnolent man. Neurological exam reveals 4 mm pupils, which are equal and reactive to light, and a patient who responds incoherently to questions when stimulated. The patient has normoactive bowel sounds and is non-tender in all 4 quadrants. Laboratory values are ordered as seen below.\n\nSerum:\nNa+: 139 mEq/L\nCl-: 100 mEq/L\nK+: 4.3 mEq/L\nHCO3-: 25 mEq/L\nBUN: 20 mg/dL\nGlucose: 99 mg/dL\nCreatinine: 1.1 mg/dL\nCa2+: 10.2 mg/dL\nEthanol: negative\n\nAn initial ECG is unremarkable. Which of the following is the best treatment for this patient?", "answer": "Observation", "options": {"A": "Flumazenil", "B": "Fomepizole", "C": "Naloxone", "D": "Observation", "E": "Sodium bicarbonate"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 6-month-old boy is brought to her pediatrician for a checkup and vaccines. He was born at 39 weeks gestation via spontaneous vaginal delivery. He is meeting all the developmental milestones. His prenatal history was complicated with maternal diabetes. He is being breastfed exclusively and has 3–4 wet diapers a day. On physical exam, the vital signs include: temperature 37.0°C (98.6°F), blood pressure 85/45 mm Hg, pulse 140/min, and respiratory rate is 31/min. On physical examination, the patient is alert and responsive. Height, weight, and head circumference are above the 90th percentile. Which of the following vaccines should be administered for this patient at this visit?", "answer": "RV, DTaP, PCV, Hib, IPV", "options": {"A": "RV, DTaP, PCV", "B": "RV, Tdap, PCV, Hib", "C": "RV, DTaP, PCV, Hib, IPV", "D": "Hep B, DTaP, Influenza", "E": "RV, Hep B, Hep A"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 23-year-old woman is brought to the emergency department 20 minutes after being involved in a high-speed motor vehicle collision where she was the unrestrained driver. She was found thrown across the dashboard of the car. On arrival, she appears lethargic. She is unable to provide a history. Her pulse is 133/min, respirations are 23/min, and blood pressure is 90/60 mm Hg. Examination shows a 2-cm laceration over the right upper extremity. The pupils are equal and reactive to light. There are multiple bruises over the chest and abdomen. The lungs are clear to auscultation. Cardiac examination shows no abnormalities. The abdomen is soft and not distended. Neurologic examination shows no focal findings. 0.9% saline infusion is begun. Which of the following is the most appropriate next step in management?", "answer": "Ultrasonography", "options": {"A": "Observation", "B": "Exploratory laparotomy", "C": "CT scan of the abdomen", "D": "Ultrasonography", "E": "Diagnostic peritoneal lavage"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "Three days after starting a new medication, a 66-year-old woman with resistant hypertension and hyperlipidemia comes to the doctor because of decreased urination. She denies dysuria, fevers, or chills. Blood pressure is 133/67 mm Hg. Physical examination shows no abnormalities. Compared to measurements from one week ago, the glomerular filtration rate is markedly decreased and plasma renin activity is elevated. A duplex ultrasound of the kidneys shows increased systolic flow velocity in both renal arteries when compared to the aorta. Which of the following drugs is the most likely cause of this patient's worsening renal function?", "answer": "Enalapril", "options": {"A": "Furosemide", "B": "Spironolactone", "C": "Hydrochlorothiazide", "D": "Enalapril", "E": "Atenolol"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "An investigator is conducting an experiment to develop a new drug against HIV infection. HIV-infected and uninfected CD4 T-cell lines are mixed in-vitro with a chemically modified synthetic peptide triazole complex. The complex is found to have a high binding affinity to the gp120 protein, irreversibly inhibiting its function and reducing CD4 T cell infection. Inhibition of which of the following steps of HIV infection is the most likely therapeutic effect of this experimental drug?", "answer": "Attachment to host CD4 T-cells", "options": {"A": "Incorporation of viral genome into host cell DNA", "B": "Transcription of the viral genome", "C": "Fusion and entry into CD4 T-cells", "D": "Assembly of viral particles", "E": "Attachment to host CD4 T-cells"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 35-year-old man presents to the physician for a medical evaluation necessary before joining the armed force services. He is a healthy man with no history of smoking or substance abuse. His past medical history is not significant. His vital signs are stable and his systemic examination is within normal limits. Examination of his respiratory system, including auscultation of his chest, does not reveal any abnormality. His laboratory investigations are within normal limits but his chest radiogram shows a solitary pulmonary nodule (SPN), size 9 mm (0.35 in) in diameter, in the middle zone of his right lung. The physician compares the radiogram with a radiogram obtained 3 years back for pre-employment medical evaluation. The physician notes that a similar SPN with the same size was present in the previous radiogram at the same location. Which of the following is the next best step in his evaluation?", "answer": "No further workup", "options": {"A": "No further workup", "B": "Thin-section computed tomography (CT) scan", "C": "Positron emission tomography (PET) scan", "D": "Follow-up after 12 months; if unchanged, no further follow-up", "E": "Follow-up every 6 months; CT scan when there are changes in the nodule"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 32-year-old man presents to his primary care physician because he has been experiencing fatigue and back pain over the last 2 days. He suffered from malaria after going on vacation 5 years ago and recently started taking a medication to deal with a latent form of this infection. He started developing these symptoms 36 hours after taking the first dose and noticed his urine became progressively darker during that time. On physical exam he is found to have scleral icterus and skin jaundice. Labs are obtained with the following results:\n\nHematocrit: 32% (Normal: 41%-53%)\nHemoglobin: 10.6 g/dL (Normal: 13.5-17.5 g/dL)\nLeukocyte count: 8500/mm3 (Normal: 4500-11,000/mm3)\nPlatelet count: 273,000/mm3 (Normal: 150,000-400,000/mm3)\n\nWhich of the following would most likely be seen on a peripheral blood smear in this patient?", "answer": "Small round inclusions of denatured hemoglobin", "options": {"A": "Helmet-shaped red blood cells", "B": "Small round inclusions of denatured hemoglobin", "C": "Small round inclusions of nuclear remnants", "D": "Target-shaped red blood cells", "E": "Teardrop-shaped red blood cells"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 30-year-old woman presents to the office for routine examination. She has no medical complaints except for mild burning sensation in her eyes and an occasional dry cough. She denies fever, headache, or any recent illnesses. Past medical history is unremarkable and she takes no medications. She does not smoke cigarettes or drinks alcohol. Her temperature is 37.0°C (98.6°F), the blood pressure is 110/70 mm Hg, the pulse is 78/min, and the respirations are 12/min. Physical examination is normal except for bilateral conjunctival injection. Laboratory results and chest X-ray is shown below:\nSerum chemistry\n  Sodium 145 mEq/L\n  Potassium 4.1 mEq/L\n  Chloride 98 mEq/L\n  Calcium 13 mEq/L\n  Bicarbonate 20 mEq/L\n  Blood urea nitrogen 8 mEq/L\n  Creatinine 0.7 mEq/L\n  Glucose 96 mEq/L\nUrine toxicology Negative\nWhich of the following abnormalities would most likely be seen in this patient?", "answer": "Increased ACE levels", "options": {"A": "Decreased alpha-1 antitrypsin levels", "B": "Increased ACE levels", "C": "Increased ADH levels", "D": "Presence of anti-dsDNA antibodies", "E": "Caseating granulomas in lung tissue biopsy"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 60-year-old man presents to a physician with the complaint of a persistent cough for a year. He has visited multiple physicians to date, but there has been no conclusive diagnosis. He has been a smoker since the age of 30. There is no history of significant expectoration, blood in sputum, wheezing, or breathing difficulty, but he has lost approx. 6.35 kg (14 lb) of weight over the last 9 months. On physical examination, his vital signs are stable, and examination of the chest reveals decreased breath sounds over the left infrascapular region. His chest radiogram suggests atelectasis in the left lower lobe. A detailed evaluation confirms a diagnosis of non-small cell lung carcinoma involving the left main bronchus, which is 4 cm in size and is located 3.8 cm (1.5 in) from the carina. Ipsilateral hilar lymph nodes, ipsilateral subcarinal lymph nodes, and ipsilateral scalene lymph nodes are involved in metastasis with no distant metastasis. Investigations also suggest that the patient does not have any comorbidity that contraindicates any anti-cancer treatment modality and that his performance status is good. Which of the following is the initial treatment of choice for the patient?", "answer": "Concurrent chemoradiotherapy", "options": {"A": "Surgery followed by adjuvant chemotherapy", "B": "Chemotherapy only", "C": "Concurrent chemoradiotherapy", "D": "Sequential chemoradiotherapy", "E": "Radiation therapy only"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A previously healthy 25-year-old woman comes to the physician because of a 3-week history of fever, recurrent headaches, and anorexia. One month ago, she returned from a camping trip in Chile. Her temperature is 39.3°C (102.8°F). Examination shows a swelling in the left periorbital region and axillary, cervical, and inguinal lymphadenopathy. A blood sample is obtained. Processing of the sample with which of the following methods is most likely to confirm the diagnosis?", "answer": "Staining with Giemsa dye", "options": {"A": "Staining of mycolic acid", "B": "Staining with India ink", "C": "Staining with Giemsa dye", "D": "Staining of glycogen", "E": "Staining with silver"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 57-year-old man presents to the emergency department with chest and back pain. He states that his symptoms started suddenly 1 hour ago and have persisted. He has a past medical history of hypertension and diabetes. His temperature is 98.5°F (36.9°C), blood pressure is 168/111 mmHg, pulse is 95/min, respirations are 14/min, and oxygen saturation is 99% on room air. Physical exam is notable for an uncomfortable man but is otherwise within normal limits. An initial ECG is unremarkable. Laboratory values are ordered as seen below.\n\nHemoglobin: 15 g/dL\nHematocrit: 45%\nLeukocyte count: 6,300/mm^3 with normal differential\nPlatelet count: 222,000/mm^3\n\nSerum:\nNa+: 141 mEq/L\nCl-: 103 mEq/L\nK+: 4.5 mEq/L\nHCO3-: 24 mEq/L\nBUN: 42 mg/dL\nGlucose: 129 mg/dL\nCreatinine: 1.9 mg/dL\nCa2+: 10.2 mg/dL\n\nWhich of the following is the best next step in management?", "answer": "Transesophageal echocardiography", "options": {"A": "Aspirin", "B": "CT angiogram of the chest", "C": "D-dimer", "D": "Esmolol", "E": "Transesophageal echocardiography"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 2-week-old infant is brought to the pediatrician for the first time by his parents. His mother received regular prenatal care and the child was born at home under the guidance of a midwife and a doula. The child appears well. The parents tell you they do not plan to have their child receive any vaccines. After a discussion regarding the risks and benefits of vaccines, the parents are still adamant in their wishes to forgo. Which of the following is the most appropriate course of action?", "answer": "Document the visit, specifically the detailing of risks and benefits and the parents' refusal of treatment", "options": {"A": "Call child protective services", "B": "Refuse to continue to care for the child", "C": "Seek a court order to deliver the vaccines against the wishes of the parents", "D": "Give any scheduled vaccines during that visit against the will of the parents", "E": "Document the visit, specifically the detailing of risks and benefits and the parents' refusal of treatment"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 15-year-old boy is brought in to his pediatrician's office by his step-mother for uncontrollable behavior. She reports he has an extensive history of detention for outbursts in class. He recently got expelled from school for fist fighting. At home, he punches his younger brother when he’s angry. The family had to give their cat away to a neighbor because the patient tried to set it on fire. The patient’s medical history is significant for bed-wetting until he was 11. His father has adult attention deficit disorder. The patient states that he thinks school is a “joke.” He denies having close friends and says “the kids in my town are stupid anyway.” He calmly describes how he would like to burn down all their houses. He admits to trying alcohol and cocaine but denies any other illicit drugs. Which of the following is the patient’s most likely diagnosis?", "answer": "Conduct disorder", "options": {"A": "Antisocial personality disorder", "B": "Attention deficient hyperactivity disorder", "C": "Conduct disorder", "D": "Pyromania", "E": "Substance abuse"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 30-year-old female complains of heat intolerance, excessive sweating, and recent unintentional weight loss. She denies alcohol, tobacco, and other drug use and does not take any medications. Laboratory analysis reveals elevated serum T4 and decreased serum TSH. You elect to manage the patient’s condition pharmacologically with methimazole. Methimazole interferes with the function of which of the following proteins?", "answer": "Thyroid peroxidase", "options": {"A": "Thyroxine-binding globulin", "B": "Sex-hormone binding globulin", "C": "Thyroid peroxidase", "D": "5’-deiodinase", "E": "Sodium/iodide symporter"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 40-year-old woman presents to her primary care physician with complaints of worsening muscle aches and diffuse weakness over the past several months. She states that she now has difficulty climbing stairs and extending her neck. Ultimately, she became more concerned when she began having trouble swallowing and experienced shortness of breath last night which has resolved. Her temperature is 98.5°F (36.9°C), blood pressure is 120/84 mmHg, pulse is 70/min, respirations are 12/min, and oxygen saturation is 98% on room air. Physical exam is notable for 2/5 strength of the proximal muscles of the upper and lower extremities. Dermatologic, cardiac, and pulmonary exam are unremarkable. The patient is tolerating oral secretions and has no difficulty swallowing or protecting her airway currently. Laboratory studies are notable for an elevated CRP and aldolase. Which of the following is the most appropriate treatment for this patient?", "answer": "Prednisone", "options": {"A": "Intravenous immunoglobulin", "B": "Methotrexate", "C": "Naproxen", "D": "Neostigmine", "E": "Prednisone"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 50-year-old woman visits her primary care practitioner with the complaints of generalized weakness, lightheadedness, and fatigability for the past month. She also claims to have epigastric pain, heartburn, and a sensation of a lump in her throat. Her family history is irrelevant, but her medical history is significant for a Pap smear that reported atypical squamous cells of undetermined significance (ASCUS), which was followed up with a cervical biopsy negative for malignancy. She occasionally takes over-the-counter medicines to cope with the heartburn, and recently her hemoglobin was found to be 11 g/dL, for which she received iron and vitamin B12 supplementation. Physical examination is unremarkable, except for pale skin, and a pulse of 120/min. Which of the following is the next best step in the management of this patient?", "answer": "Endoscopy", "options": {"A": "Proton pump inhibitor", "B": "Anti-H2 agent", "C": "Endoscopy", "D": "Fecal occult blood test", "E": "Diet and lifestyle recommendations"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 67-year-old man presents to a primary care clinic to establish care after moving from another state. According to his prior medical records, he last saw a physician 4 years ago and had no significant medical problems at that time. Records also show a normal EKG and normal colonoscopy results at that time. The patient reports feeling well overall, but review of systems is positive for 1 year of mild cough productive of clear sputum and 2 years of increased urinary frequency. He denies fever, chills, dyspnea, dysuria or hematuria. He denies illicit drug use but has been drinking approximately 1-2 beers per night and smoking 1 pack of cigarettes per day since age 20. Physical exam is unremarkable. Which of the following tests is indicated at this time?", "answer": "Abdominal ultrasound", "options": {"A": "Abdominal ultrasound", "B": "Bladder ultrasound", "C": "Colonoscopy", "D": "Serum prostate specific antigen (PSA) testing", "E": "Sputum culture"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "An 8-year-old boy is brought to the physician for evaluation of an excessive bleeding after undergoing a dental procedure. Laboratory studies show a platelet count of 195,000/mm3, a partial thromboplastin time of 44 sec, and a prothrombin time of 12 sec. A one-stage clotting assay shows a decreased factor VIII. Therapy with a drug that acts on endothelial cells is initiated. This drug is most likely to result in which of the following?", "answer": "Increased permeability to urea in the collecting duct", "options": {"A": "Decreased cAMP in renal tubular cells", "B": "Increased tubular fluid osmolarity in the loop of Henle", "C": "Decreased binding of angiotensin II to AT1 receptor", "D": "Increased permeability to urea in the collecting duct", "E": "Increased bleeding time"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A young girl is brought to the physician by her mother for a well-child examination. She is at the 55th percentile for height and at the 40th percentile for weight. Vital signs are within normal limits. Physical examination shows no abnormalities. She is able to follow simple commands, such as “close your eyes, then stick out your tongue,” but she is unable to follow 3-step commands. She knows approximately 75 words, and half of her speech is understandable. She can say 2-word phrases, and she is able to name many parts of the body. Assuming normal development, which of the following milestones would be expected in a patient this age?", "answer": "Kicks a ball", "options": {"A": "Separates easily from parents", "B": "Kicks a ball", "C": "Pedals a tricycle", "D": "Hops on one foot", "E": "Draws a triangle"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "An investigator is studying the association between exclusive breastfeeding and body weight in infants. The body weights of 15 exclusively breastfed infants at the age of 6 months are measured. Results are shown:\nPatient Body weight (kg)\n1 7.0\n2 6.0\n3 6.1\n4 6.8\n5 7.2\n6 6.4\n7 6.2\n8 6.8\n9 6.5\n10 7.3\n11 6.3\n12 8.5\n13 6.9\n14 6.6\n15 5.2\nOne of the computed measures of central tendency is 6.8 kg. Which of the following characteristics is generally true about this measurement?\"", "answer": "It is resistant to outliers.", "options": {"A": "It is the 50th percentile of a set of values.", "B": "It is not applicable for qualitative data analysis.", "C": "It is resistant to outliers.", "D": "Its value only occurs once in a data set.", "E": "It is useful to assess the extent of data variability."}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 32-year-old man presents to his primary care provider with right leg weakness and numbness. He reports a 2-day history of “clumsiness” in his right lower extremity after playing in his company’s annual weekend-long charity baseball tournament. He says a similar episode happened 1 year ago during the same tournament. He has a history of major depressive disorder and right distal radius fracture status post-closed reduction and casting after falling 2 years ago. He takes fluoxetine. He also reports that he several years ago he had an isolated episode of decreased vision and inability to move his right eye that resolved on its own. He has a 15-pack-year smoking history and drinks 3-4 beers per week. His temperature is 98.4°F (36.9°C), blood pressure is 115/65 mmHg, pulse is 85/min, and respirations are 18/min. On exam, hip flexion, knee extension, and ankle dorsiflexion are all 3/5 on his right and 5/5 on his left. Right Achilles and patellar reflexes are 1+ on the right and 2+ on the left. He has decreased sensation to light touch throughout the right leg especially below the knee. Additional questioning would most likely reveal which of the following additional features about this patient’s current symptoms?", "answer": "Symptom exacerbation in the heat", "options": {"A": "Concomitant hyperreflexia", "B": "Symptom improvement in the heat", "C": "Symptom exacerbation in the heat", "D": "Symptom exacerbation with repetitive muscle contractions", "E": "Symptom improvement with repetitive muscle contractions"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 56-year-old man comes to the physician because of throat pain and increasing difficulty swallowing food for the past 5 months. He has also had episodic left ear pain for the past 3 months. He has hypertension. His only medication is amlodipine. His father died of laryngeal cancer at the age of 55 years. He has smoked one pack of cigarettes daily for 36 years. He drinks 2–3 beers daily. Vital signs are within normal limits. Examination shows left cervical lymphadenopathy. Oropharyngeal examination shows a 3-cm ulcerating left tonsillar mass. Examination of both auditory canals is unremarkable. Which of the following is the most appropriate initial step in management?", "answer": "Panendoscopy", "options": {"A": "Esophagoscopy", "B": "Nasopharyngoscopy", "C": "Panendoscopy", "D": "Barium swallow", "E": "Laryngoscopy\n\""}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 23-year-old woman presents to the emergency department with abdominal pain. The patient states that she has pain in her back that radiates to her abdomen. The pain started yesterday and is episodic. She describes the pain as a 10/10 when it occurs. The patient has a past medical history of asthma, anxiety, and chlamydia that was appropriately treated. Her current medications include fluoxetine. The patient's lab values are ordered as seen below.\n\nHemoglobin: 14 g/dL\nHematocrit: 40%\nLeukocyte count: 8,500 cells/mm^3 with normal differential\nPlatelet count: 225,000/mm^3\n\nSerum:\nNa+: 140 mEq/L\nCl-: 100 mEq/L\nK+: 4.9 mEq/L\nHCO3-: 24 mEq/L\nBUN: 22 mg/dL\nGlucose: 89 mg/dL\nCreatinine: 1.2 mg/dL\nCa2+: 10.0 mg/dL\nAST: 11 U/L\nALT: 11 U/L\n\nUrine:\nColor: amber\nNitrites: negative\nNa+: 12 mmol/24 hours\nBeta-hCG: positive\nRed blood cells: 11/hpf\n\nWhich of the following is the best test for this patient's most likely diagnosis?", "answer": "Renal ultrasound", "options": {"A": "Abdominal radiograph", "B": "Abdominal CT", "C": "Transvaginal ultrasound", "D": "Abdominal ultrasound", "E": "Renal ultrasound"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A baby is delivered via cesarean section on the 31st gestational week. The child has tachypnea, nasal flaring, and subcostal, and intercostal retraction. Nasogastric tube was positioned without problems. Chest radiography shows bilateral, diffuse, ground-glass appearance, air bronchograms, and poor lung expansion. What is the best treatment plan in the present case?", "answer": "Surfactant administration and oxygen therapy", "options": {"A": "Oxygen therapy", "B": "No therapy right away, only observation", "C": "Surfactant administration and oxygen therapy", "D": "Antibiotics", "E": "Emergency surgical repair of tracheoesophageal fistula"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A previously healthy 38-year-old man comes to the emergency department for evaluation of several hours of severe, right-sided, colicky flank pain that radiates to the groin. He drinks 2–3 energy drinks daily. An x-ray of the abdomen shows a 4-mm radiopaque mass in the right ureter. Microscopic examination of the urine shows biconcave, dumbbell-shaped crystals. Which of the following is most likely to prevent future episodes of flank pain?", "answer": "Maintain adequate hydration", "options": {"A": "Begin loop diuretic", "B": "Maintain acidic urine", "C": "Maintain adequate hydration", "D": "Start high-dose vitamin C", "E": "Restrict dietary calcium intake"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 45-year-old woman presents for evaluation of mild painless postcoital bleeding for the past 6 months. Recently, she started to note irregular intermenstrual bleeding. She has a regular menstrual cycle that lasts 30 days. She has no history of genital infections or any other major gynecologic diseases. She has 1 sexual partner and uses barrier contraception for birth control. The pelvic examination shows an erosive necrotizing lesion (6 cm in diameter) that involves the posterior lip of the cervix and extends to the cervical canal and posterior vaginal apex. Cervical mobility is decreased. The uterus is not enlarged and the ovaries are non-palpable. A colposcopy is performed and a biopsy is obtained. The histologic evaluation shows irregularly-shaped nests of squamous epithelium cells with large pleomorphic nuclei, inconspicuous nucleoli, a clear cytoplasm, and increased mitoses that infiltrate the stroma for greater than 10 mm. Which of the following investigations is the main method for staging the patient’s condition?", "answer": "Clinical examination", "options": {"A": "Pelvic MRI", "B": "Surgical evaluation", "C": "Clinical examination", "D": "Pelvic CT", "E": "PET-CT"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 69-year-old man presents for surgery due to chronic painful diverticula in the sigmoid colon. The patient is a Jehovah's witness and refuses a transfusion of blood products even in an emergency. Which artery should be briefly clamped to prevent bleeding during the partial sigmoidectomy?", "answer": "Inferior mesenteric artery", "options": {"A": "Superior mesenteric artery", "B": "Inferior mesenteric artery", "C": "Celiac trunk", "D": "Inferior rectal artery", "E": "Splenic artery"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A thymic sample from a fetus is examined. One cell type found was double-positive for the CD4 and CD8 receptors. What is the identity of these double-positive cells?", "answer": "Immature T-cells of the thymic cortex", "options": {"A": "T-cell progenitors cells in the bone marrow", "B": "B-cells", "C": "Immature T-cells of the thymic cortex", "D": "Immature T-cells of the thymic medulla", "E": "Macrophages"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "An investigator is studying the antimicrobial resistance profile of a bacterial pathogen using disk diffusion testing. The pathogen is isolated onto agar plates and antibiotic wafers are added to the plates. The inhibitory zone diameters are then recorded and used to define susceptibility thresholds. The results of the testing for the pathogen shown:\nDrug Susceptibility\nPenicillin G Resistant\nCefazolin Resistant\nDoxycycline Susceptible\nImipenem Resistant\nAzithromycin Susceptible\nVancomycin Resistant\nWhich of the following is most likely the organism being studied?\"", "answer": "Ureaplasma urealyticum", "options": {"A": "Staphylococcus aureus", "B": "Clostridioides difficile", "C": "Pseudomonas aeruginosa", "D": "Borrelia burgdorferi", "E": "Ureaplasma urealyticum"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 30-year-old man comes to the physician for evaluation of infertility. He does not smoke, drink, or take any medications. Physical examination shows no abnormalities. Serum analysis shows anti-sperm antibodies. What is the most likely cause of this patient's serum finding?", "answer": "Defect in Sertoli cell function", "options": {"A": "Increase in testicular temperature", "B": "Dysgenesis of seminiferous tubules", "C": "Dysgenesis of vas deferens", "D": "Defect in Sertoli cell function", "E": "Defect in GnRH production\n\""}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A mother calls the psychiatrist, saying that she is concerned about her 18-year-old son who has become quite emaciated over the past several months. She has noticed that his pupils are enlarged, he has frequent nose bleeds, and he wears long sleeve shirts even in warm weather. His personality has changed quite dramatically as well, as he repeatedly steals from her and sells anything valuable in the house. He also has become overconfident, aggressive, and paranoid. Which of the following is a risk of the drug that the son is most likely using?", "answer": "Sudden cardiac arrest", "options": {"A": "Serotonin syndrome", "B": "Sudden cardiac arrest", "C": "CNS white matter lesions", "D": "Irreversible schizophrenia-like psychosis", "E": "Increased risk of schizophrenia in predisposed patients"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 48-year-old man is brought to the physician by his wife because he has become increasingly restless and anxious. His wife says that he has seemed sad and irritable for the past 4 months. He lost his job as a store clerk because he often lied to avoid work, and spent most of his days on the phone placing bets on football games. He avoids all family-related events because he has borrowed money from most of his relatives. He is hopeful that his symptoms will improve once he is able to win some of his money back. He previously smoked 8–10 cigarettes daily but quit 1 month ago. He drinks beer on the weekends. On examination, he is uncooperative and dismissive. He is mildly tremulous. Neurologic examination is normal. He is oriented to person, place, and time. Which of the following is the most likely diagnosis?", "answer": "Gambling disorder", "options": {"A": "Gambling disorder", "B": "Opioid withdrawal", "C": "Alcohol withdrawal", "D": "Bipolar II disorder", "E": "Adjustment disorder"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 28-year-old man comes to the emergency department because of an excruciating headache that started 30 minutes ago. The pain is located around the right eye and it awoke him from sleep. Over the past two weeks, he has had similar headaches around the same time of the day, and he reports pacing around restlessly during these episodes. Physical examination shows conjunctival injection and tearing of the right eye. In addition to supplemental oxygen therapy, administration of which of the following drugs is most likely to provide acute relief in this patient?", "answer": "Sumatriptan", "options": {"A": "Sumatriptan", "B": "Ibuprofen", "C": "Amitriptyline", "D": "Prednisone", "E": "Oxycodone"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 27-year-old woman presents with loss of consciousness at work. The patient’s colleagues say that she had been complaining of a headache all day. Her past medical history is significant for diabetes mellitus type 1. Her blood pressure is 70/60 mm Hg, pulse is 105/min, temperature is 37.2°C (99.0°F), and her respiratory rate is 28/min and shallow. On physical examination, there is a black eschar formation on her nose and her breath has a fruity odor. Laboratory findings are significant for serum glucose of 750 mg/dL, potassium of 3.3 mmol/L, and blood pH of 7.1. Which of the following diabetic complications is most likely the cause of this patient’s presenting symptoms?", "answer": "Diabetic ketoacidosis", "options": {"A": "Diabetic ketoacidosis", "B": "Hyperosmolar coma", "C": "Lactic acidosis", "D": "Hypoglycemic coma", "E": "Hemorrhagic stroke"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 61-year-old male presents to his primary care doctor with a six-month history of progressively worsening cough, shortness of breath, and 15-pound weight loss. Over the same time period, he has also started to notice occasional weakness in his legs that has made it difficult for him to stand up from his chair and climb stairs. The weakness appears to improve when he exercises at his local aerobics class. His past medical history is notable for hypertension and hyperlipidemia. He has smoked 2 packs of cigarettes per day for 35 years. Chest radiographs demonstrate a perihilar mass in his right lung. A biopsy of the lung lesion is shown. Which of the following is most likely true about this patient?", "answer": "His weakness improves when calcium builds up in the presynaptic nerve terminal", "options": {"A": "His weakness is due to a type III hypersensitivity reaction", "B": "He is at high risk of developing extraocular weakness", "C": "His weakness is due to antibodies directed against post-synaptic, voltage-gated ion channels", "D": "Administering a cholinesterase inhibitor will improve his symptoms", "E": "His weakness improves when calcium builds up in the presynaptic nerve terminal"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 45-year-old man with a history of hypertension, IV drug use, and type 1 diabetes is brought to the emergency room due to nausea, vomiting, and altered consciousness. He was brought in by his sister who found him asleep on her couch. He is difficult to arouse and does not respond to questions. His sister does not know his medications; however, he has a known history of medication noncompliance. On physical exam his temperature is 99°F (37.2°C), blood pressure is 100/70 mmHg, pulse is 112/min, respirations are 26/min, and pulse oximetry is 99% on room air. He is arousable but is not cooperative with the exam. His breaths are deep and you notice a fruity-smell coming from his mouth. Exam is otherwise unremarkable. Which of the following findings would you also expect to see in this patient?", "answer": "Decreased total body potassium", "options": {"A": "Decreased total body potassium", "B": "Decreased lactate concentration", "C": "Increased bicarbonate concentration", "D": "Decreased hydrogen ion concentration", "E": "Decreased free fatty acid concentration"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 31-year-old woman and her 32-year-old husband come to the physician because they have not been able to conceive since they married 1.5 years ago. They are sexually active and have not used any form of contraception during this period. She was diagnosed with cervicitis due to Chlamydia trachomatis infection 4 years ago, which was treated with oral azithromycin. The wife reports that she has regular menses and is otherwise healthy. Her last menstrual bleeding was 2 weeks ago. Neither partner shows abnormalities on physical examination. Which of the following is the most appropriate next step in management?", "answer": "Semen analysis", "options": {"A": "Clomiphene citrate challenge test", "B": "Chromosomal karyotyping", "C": "Postcoital testing", "D": "Post-ejaculatory urinalysis", "E": "Semen analysis"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 66-year-old man comes to the physician with a 4-month history of recurrent crusty lesions on the dorsal surface of his hands. When he scrapes off the crusts, they reappear after a few days. The lesions are mildly pruritic and occasionally burn. He works as a landscaper. A photograph of his right hand is shown. Which of the following is the most likely diagnosis?", "answer": "Actinic keratosis", "options": {"A": "Sporotrichosis", "B": "Basal cell carcinoma", "C": "Actinic keratosis", "D": "Lichen planus", "E": "Seborrheic keratosis\n\""}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 50-year-old woman presents to the emergency department with severe abdominal pain and discomfort for several hours. She says that the pain started suddenly and rates it as an 8/10 pain. There are no exacerbating factors but the pain gets relieved by leaning forward. She also complains of nausea and vomiting. She has vomited 4 times in the last 2 hours. Her past medical history is significant for HIV, diabetes, asthma, depression, and acute angle glaucoma. She states that she is very diligent with her medications and has never missed a pill. She says that she does not smoke or drink alcohol. Her temperature is 37°C (98.6°F), respirations are 15/min, pulse is 97/min, and blood pressure is 102/98 mm Hg. On examination, she is pale, diaphoretic, and in extreme discomfort. She does not allow an abdominal exam. Laboratory results show a serum amylase of 456 U/L and a serum lipase of 562 U/L. Treatment of which of the following conditions most likely led to this patient's current condition?", "answer": "Acquired immunodeficiency syndrome", "options": {"A": "Asthma", "B": "Acute angle glaucoma", "C": "Acquired immunodeficiency syndrome", "D": "Depression", "E": "Diabetes"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 66-year-old man is brought to the emergency department after 3 consecutive days of nausea and multiple episodes of vomiting every day. He has been receiving cisplatin as part of treatment for small cell lung carcinoma diagnosed about a year ago. Upon admission, he is found to be drowsy with muscle weakness. The patient’s vital signs are as follows: blood pressure is 98/60 mm Hg, heart rate is 120/min, respiratory rate is 14/min, and body temperature is 36.5°C (97.7°F). Physical examination reveals a mildly cachectic male with mild abdominal tenderness to palpation. The following tests are performed:\nLaboratory test\nSerum Na+ 136 mEq/L\nSerum Cl- 78 mEq/L\nSerum K+ 3.0 mEq/L\nSerum creatinine (SCr)  1.0 mg/dL\n    Arterial blood gas\npH 7.58\nPO2 95 mm Hg\nPCO2 49 mm Hg\nSO2% 98%\nHCO3- 44.4 mEq/L\nWhich of the following is the most likely cause of this patient’s acid-base abnormality?", "answer": "Excessive hydrogen ion loss", "options": {"A": "Increased potassium secretion", "B": "Excessive hydrogen ion loss", "C": "Carbon dioxide retention", "D": "Increased bicarbonate absorption", "E": "Decreased bicarbonate excretion"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 30-year-old woman presents with a white patch on her tongue that she noticed a few weeks ago. She denies any changes in taste sensation or pain, weight loss, or night sweats. Past medical history is significant for a 10-year history of type 1 diabetes mellitus, managed currently on insulin therapy. Her last HbA1c a month ago was 9%. On physical examination, there are white patches present over the dorsum of her tongue (as seen in the image) that can easily be scraped off. Microscopic examination of KOH treated scrapings shows pseudohyphae. The patient is advised to have better blood glucose control and is prescribed a drug for these oral patches, which she is instructed to swish in her mouth for several minutes and then swallow. Which of the following best describes the mechanism of action of this drug?", "answer": "Disruption of cell membrane integrity", "options": {"A": "Inhibition of synthesis of lanosterol", "B": "Inhibit of synthesis of ergosterol", "C": "Inhibit of cell wall synthesis", "D": "Disruption of cell membrane integrity", "E": "Inhibition of nucleic acid synthesis"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 34-year-old African-American woman comes to the physician because of a 6-month history of fatigue, increasing shortness of breath on exertion, and a dry cough. She also has chronic constipation with bowel movements once every two to three days. She has not had fevers, night sweats, or weight loss. She has a history of hypertension and arthritis of both ankle joints. Current medications include hydrochlorothiazide and daily multivitamins. Her vital signs are within normal limits. Her serum sodium is 138 mEq/L, potassium is 3.9 mEq/L, and calcium is 11.5 mg/dL. An x-ray of the chest shows bilateral hilar lymphadenopathy and normal lung parenchyma. Which of the following is the most likely cause of this patient's hypercalcemia?", "answer": "Elevated 1,25-dihydroxyvitamin D3 levels", "options": {"A": "Elevated 1,25-dihydroxyvitamin D3 levels", "B": "PTH-related protein production", "C": "Thiazide-induced renal calcium reabsorption", "D": "Chronic kidney disease", "E": "Vitamin A toxicity\n\""}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 78-year-old man comes to the physician because of difficulty swallowing and regurgitation of undigested food for the past several months. The patient reports that his symptoms have gotten progressively worse. Physical examination shows severe halitosis and a gurgling sound after he swallows a small amount of water. Results of fluoroscopic barium esophagography are shown. The nerve responsible for motor innervation of the affected muscle is also responsible for which of the following functions?", "answer": "Parasympathetic innervation of the AV node", "options": {"A": "Parasympathetic innervation of the AV node", "B": "Sensory innervation of the posterior tongue", "C": "Visceral sensory innervation of the carotid sinus", "D": "Motor innervation of the ventral tongue", "E": "Somatosensory innervation of the semi-circular canals"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 1-day-old boy is brought to the emergency department by ambulance after his parents found him to be increasingly lethargic. He was born at home with inconsistent prenatal care. Since then, his parents report that his head appears to be getting bigger over the past few hours. He also feeds poorly and has had a few episodes of vomiting. On presentation, he is found to have limb spasticity with adducted thumbs. His head circumference is bigger than expected and he appears to be unable to look up when following objects. Which of the following findings would most likely also be seen in this patient?", "answer": "Obstruction of the cerebral aqueduct", "options": {"A": "Abnormally large posterior fossa", "B": "Downwardly displaced cerebellum", "C": "Elongated facial structure", "D": "Obstruction of the cerebral aqueduct", "E": "Tuft of hair on the spine"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 48-year-old woman presents to the emergency department with a 2-day history of chest pain. The patient’s symptoms started gradually after moving heavy objects during packing. The pain is constant and nagging but intensifies with lateral movement. The patient has no history of serious illness and takes no medications, currently. She does not smoke. Her vitals are as follows: blood pressure 125/75 mm Hg; pulse 75/min; respiratory rate 14/min; and temperature 36.9℃ (98.4℉). Examination of the anterior chest wall shows the absence of swelling, erythema, or warmth. The 3rd and 4th left rib bones are tender anteriorly near the sternum. An electrocardiogram is shown. The test for cardiac troponin I is negative. Which of the following is the most appropriate initial step in the management of this patient?", "answer": "Ibuprofen", "options": {"A": "Ibuprofen", "B": "Intercostal nerve block", "C": "Local injection of lidocaine (for Tietze syndrome, which is unresponsive to NSAIDs)", "D": "Serial ECG for 12 hours", "E": "Sublingual nitroglycerin"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 28-year-old woman who recently immigrated from Kenya presents with fatigue, shortness of breath, and palpitations for a few weeks. Review of systems is significant for a painful swollen knee. The patient is afebrile, and her vital signs are within normal limits. On physical examination, her voice seems hoarse, although her pharynx does not show signs of an inflammatory process. Cardiopulmonary auscultation is significant for a loud first heart sound with a split second heart sound and a mid-diastolic rumbling murmur with an opening snap best heard over the cardiac apex. Transthoracic echocardiography shows a calcified mitral valve with an opening area of 1.5 cm2 (normal: 3.0–3.5 cm2). The patient is recommended to have her mitral valve replaced because of the risk for complications such as atrial fibrillation which may lead to the formation of a life-threatening blood clot that can travel to other parts of the body. Which of the following organs is most likely to be spared in this patient?", "answer": "Lungs", "options": {"A": "Lungs", "B": "Kidneys", "C": "Spleen", "D": "Brain", "E": "Small bowel"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 14-year-old girl with a BMI of 17 complains of frequent urination, excessive thirst, and abdominal pain. Her parents have noticed that she appears to have lost some weight. Her past medical history is significant for celiac disease. A random plasma blood glucose is 267 mg/dL. Which of the following is a property of the hormone that is deficient in this patient?", "answer": "Enhances potassium uptake", "options": {"A": "Down-regulates glycogen synthase activity", "B": "Up-regulates glycogen phosphorylase activity", "C": "Enhances potassium uptake", "D": "Downregulates HMG-CoA reductase", "E": "Crosses the placenta to affect the fetus"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 37-year-old woman presents to her primary care physician with a 6-month history of fatigue. She denies any recent history of fevers, chills or headaches. She does not smoke or drink alcohol. A CBC demonstrates a microcytic anemia. Iron studies are ordered and demonstrate the following:\nSerum iron: 40 µg/dL (normal 50–170 µg/dL);\nTIBC: 230 µg/dL (normal 250–370 µg/dL);\nTransferrin saturation: 10% (normal 15–50%);\nSerum ferritin: 180 µg/L (normal 15-150 µg/L);\nWhich of the following is a likely cause of this patient's iron studies findings?", "answer": "Rheumatoid arthritis", "options": {"A": "Lead poisoning", "B": "Dysfunctional uterine bleeding", "C": "Splenic sequestration of RBCs", "D": "Rheumatoid arthritis", "E": "RBC enzyme deficiency"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 32-year-old man presents with epigastric gnawing pain occurring after meals. Occasionally, dull pain awakens him at night. He also complains of bloating and occasional constipation. He has been having these symptoms for almost 2 years and uses antacids and castor oil for relief. Recently, he began to note that these remedies provide less relief than in the past. He reports no significant weight loss, night sweats, or a change in stool color. He has no family history of peptic ulcer disease or gastrointestinal malignancies. The patient does not smoke cigarettes but drinks alcohol occasionally. He rarely uses NSAIDs for symptomatic treatment. His blood pressure is 120/80 mm Hg, heart rate is 85/min, respiratory rate is 14/min, and temperature is 36.6°C (97.9°F). A physical examination revealed epigastric tenderness on palpation and the abdomen was distended. A urea breath test was performed, which was positive. Which of the following statements regarding the test results in this patient is true?", "answer": "The causative agent possesses urease; thus, it is possible to detect urease by giving the patient urea with labeled C-14 orally and then measuring the carbon dioxide content in the exhaled breath.", "options": {"A": "The test detected increased ammonia content in the patient’s exhaled breath with qualitative tests for ammonia detection.", "B": "The test detected products of increased cellular breakdown by the causative agent induced by urea ingestion.", "C": "The causative agent possesses urease; thus, it is possible to detect urease by giving the patient urease with labeled N-14 orally and then measuring the ammonia content in the exhaled breath.", "D": "The causative agent possesses urease; thus, it is possible to detect urease by giving the patient urea with labeled C-14 orally and then measuring the carbon dioxide content in the exhaled breath.", "E": "The causative agent possesses urease; thus, it is possible to detect urease by giving the patient urease and then measuring the pH of the exhaled breath to determine whether or not there was an increased breakdown of ammonia."}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 45-year-old man is brought into the emergency department after he was found collapsed in a housing development stairwell. He was found in a pool of vomit, barely breathing. Used syringes and a tourniquet were found near the patient. His blood pressure is 100/70 mm Hg, pulse is 65/min, and respiratory rate is 6/min. Physical examination reveals a thin and disheveled man with track marks on both arms. The appropriate reversal agent is administered. Which of the following findings would be most likely seen in this patient as a result of administering  this reversal agent?", "answer": "Yawning", "options": {"A": "Yawning", "B": "Miosis", "C": "Smooth skin", "D": "Pupil constriction", "E": "Tremulousness"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 33-year-old woman comes to the physician because of a 1-year history of irregular menses and infertility. She has a history of an eating disorder and has received dietary and behavioral therapy over the past 6 months with minimal improvement in her symptoms. She is 170 cm (5 ft 7 in) tall and weighs 49 kg (104 lb); her BMI is 17 kg/m2. Physical examination is significant for pallor and thin, soft, depigmented hair on the arms and back. After an extensive workup, the physician recommends pulsatile GnRH therapy. One week after initiating therapy, a pelvic ultrasound shows a 24-mm hypoechogenic cavity in the right ovary. The patient subsequently receives a drug that results in the resumption of meiosis and the loss of gap junctions between the cumulus granulosa cells and the oocyte. This patient most likely received which of the following drugs?", "answer": "Human chorionic gonadotropin", "options": {"A": "Follicle-stimulating hormone", "B": "Mifepristone", "C": "Human chorionic gonadotropin", "D": "Medroxyprogesterone", "E": "Cyproterone citrate"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 52-year-old woman visits her primary care practitioner, who has been following her closely after she was diagnosed with peptic ulcer disease. She tested positive for H. pylori in a urea breath test, which was later confirmed by an endoscopic biopsy. Her family history is significant for colorectal carcinoma, as well as ovarian cancer. Her past medical history is relevant for cigarette smoking and peptic ulcer disease, which has been under treatment twice, initially with a clarithromycin-containing regime. This was followed by a bismuth-containing regime after a fecal antigen test was positive 4 weeks later. A recent endoscopy and fecal antigen test detected H. pylori in her stomach mucosa. In addition to a protein pump inhibitor (PPI), which of the following should be added to the treatment regime of this patient?", "answer": "Levofloxacin, amoxicillin", "options": {"A": "Bismuth subsalicylate, metronidazole, tetracycline", "B": "Levofloxacin, amoxicillin", "C": "Levofloxacin, nitazoxanide, and doxycycline", "D": "Clarithromycin, amoxicillin", "E": "Rifabutin, amoxicillin"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "An 8-year-old boy is brought to the pediatrician’s office with his mother for a routine check-up. Although her son is doing well, the mother has some concerns with regards to his overall health. He was born at 39 weeks gestation via spontaneous vaginal birth. He is up to date on all vaccines and has met most of developmental milestones. She reports that he is shorter than his classmates and seems less developed physically than his older brother and sister when they were his age. Additionally, the boy’s teacher has some concerns regarding his learning capability not being at the level of his peers. His height and weight are at the 10th and 15th percentile respectively. He has a heart rate of 90/min, respiratory rate of 22/min, blood pressure of 110/65 mm Hg, and temperature of 37.0°C (98.6°F). At physical exam the child appears cheerful, well developed, and well nourished. He is small for his age. with upslanting palpebral fissures, flat occiput, low set ears, and a flat nose. Which of the following techniques would most likely identify the cause of this patient’s presentation?", "answer": "Karyotype", "options": {"A": "Punnett square", "B": "LOD score", "C": "Karyotype", "D": "Polymerase chain reaction", "E": "Gene mapping"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 55-year-old woman visits her primary care provider for concerns of frequent headaches. She complains of recurrent headaches and involuntary weight loss, which she attributes to a constant pain along the right side of her jaw that occasionally radiates to her right eye. Her past medical history includes diabetes mellitus type 2 and chronic glomerulonephritis resulting in stage II chronic kidney disease. Her mother passed away in her 70s and had been diagnosed with multiple sclerosis at the age of 50. Today, her blood pressure is 135/90 mm Hg, heart rate is 88/min, respiratory rate is 15/min, and temperature is 36.6°C (97.9°F). The right side of her face is painful to palpation from her jaw to the right side of her scalp. Which of the symptoms below is most commonly associated with the patient’s condition?", "answer": "Neck stiffness", "options": {"A": "Limb muscle weakness", "B": "Neck stiffness", "C": "Diplopia", "D": "Heliotrope rash", "E": "Shock-like pain in face"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 66-year-old man presents to his primary care provider for a routine checkup. He says that he feels well overall but has experienced some intermittent back pain and vague epigastric pain over the past 6 months. He also has experienced cramping in both legs that is worse whenever he walks for long periods of time. He has a history of poorly controlled hypertension, diabetes mellitus, recurrent renal stones, and major depressive disorder. He takes lisinopril, nifedipine, metformin, glyburide, and fluoxetine. He has a 55-pack-year smoking history and drinks alcohol socially. His temperature is 98.4°F (36.9°C), blood pressure is 155/85 mmHg, pulse is 92/min, and respirations are 16/min. On exam, he is well-appearing and in no acute distress. A normal S1 and S2 are heard on auscultation. He has no abdominal tenderness to palpation. A light pulsatile mass is felt in the mid-epigastrium. Achilles and patellar reflexes are 2+ bilaterally. His gait is normal. Which of the following additional findings is most strongly associated with this patient’s condition?", "answer": "Abdominal bruit", "options": {"A": "Abdominal bruit", "B": "Asymmetric upper extremity pulses", "C": "Continuous machine-like murmur", "D": "Costovertebral tenderness", "E": "Diastolic decrescendo murmur"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 17-year-old male collapses 25 minutes into a soccer game. He is unresponsive and pulseless. Despite adequate resuscitation by a bystander, the patient is pronounced dead when the ambulance arrives. The patient had no past medical history other than a heart murmur as a child and he took no medications. His family history is notable for an uncle who died suddenly of unknown causes at the age of 25. A mutation in which of the following proteins most likely contributed to this patient’s condition?", "answer": "Myosin heavy chain", "options": {"A": "Myosin heavy chain", "B": "Dystrophin", "C": "Tropomyosin", "D": "Fibrilin", "E": "Elastin"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 36-year-old woman, gravida 3, para 2, at 31 weeks' gestation comes to the emergency department because of painless, bright red vaginal bleeding for one day. She has not felt any contractions. Her other children were delivered by Cesarean section because of breech position. Fetal heart rate is reactive with no decelerations. Which of the following findings is most likely on ultrasound?", "answer": "Placenta over the cervical os", "options": {"A": "Retroplacental hematoma", "B": "Adnexal bleeding", "C": "Placenta over the cervical os", "D": "Gestational sac in a dilated cervix", "E": "Membranous umbilical vessels"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 24-year-old man is brought to the emergency department for bowling at a local bowling alley while inappropriately dressed. The patient refused to speak with police and was seen conversing with inanimate objects in the back of the police car. The patient states that his clothes were contaminated by assassins who have been tracking him for years. The patient refuses to answer any further questions, and continues to whisper toward someone else. The patient has a past medical history of homelessness, alcohol abuse, marijuana use, and cocaine abuse. Physical exam is notable for a healthy young man who seems mistrustful of all hospital personnel. The patient is started on a medication and is transferred to the psychiatric inpatient unit. The patient’s condition improves, but he still often speaks of a contamination that is on his clothes and skin that is coming from external parties. The patient is started on a new medication. He is then sent to group therapy, followed by physical activity in the yard. The physician is called over when the patient is found down in the recreation yard while he was exercising. The patient is not responsive, and his limbs seem to resist passive force. His temperature is 104°F (40°C), pulse is 112/min, blood pressure is 140/90 mmHg, respirations are 18/min, and oxygen saturation is 95% on room air. Which of the following best describes the most likely diagnosis?", "answer": "Dopamine blockade", "options": {"A": "Defective ryanodine receptor", "B": "Dehydration", "C": "Dopamine blockade", "D": "Inadequate evaporative cooling", "E": "Infection"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 23-year-old male presents to the emergency department after he was found naked wandering his neighborhood. The patient is disheveled and has not bathed in months. The patient has a past medical history of alcohol abuse and schizophrenia that is well controlled with haloperidol. The patient is started on haloperidol and most of his symptoms improve dramatically; however, he continues to refuse to eat food from the hospital as he believes it to be contaminated. The patient stays on the inpatient psychiatric unit and lab values are drawn and return as follows:\n\nSerum:\nNa+: 135 mEq/L\nK+: 3.0 mEq/L\nCl-: 92 mEq/L\nHCO3-: 22 mEq/L\nBUN: 7 mg/dL\nCa2+: 8.4 mg/dL\nCreatinine: 0.6 mg/dL\nGlucose: 70 mg/dL\n\nThat patient is started on an intravenous solution containing potassium chloride and is closely monitored. His oral intake also seems to be improving. Lab values are ordered again the following day and return as follows:\n\nSerum:\nNa+: 137 mEq/L\nK+: 2.9 mEq/L\nCl-: 95 mEq/L\nHCO3-: 22 mEq/L\nBUN: 8 mg/dL\nCa2+: 9.0 mg/dL\nCreatinine: 1.0 mg/dL\nGlucose: 77 mg/dL\n\nThe patient is continued on IV fluids and his clinical symptoms seem to further improve. Repeat labs the following three days remains largely unchanged. The patient's symptoms improve and he is determined to be at his baseline in terms of functioning. Which of the following is the best next step in management?", "answer": "IV fluids containing magnesium", "options": {"A": "Discharge the patient on IM haloperidol", "B": "Discharge the patient on oral haloperidol", "C": "IV fluids containing potassium", "D": "IV fluids containing magnesium", "E": "Increase oral intake"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 2-year-old girl is brought to the physician because of high-grade fever and crying while passing urine. Four months ago, she was treated for a febrile urinary tract infection with cefixime. There is no family history of serious illness. Her temperature is 39.2°C (102.6°F) and pulse is 123/min. Physical examination shows no abnormalities. Urine dipstick shows leukocyte esterase; urinalysis shows WBCs. Urine culture shows Escherichia coli sensitive to cefixime. A voiding cystourethrogram is shown. Without treatment, which of the following is this patient most likely to develop?", "answer": "Renal scarring", "options": {"A": "Renal cell carcinoma", "B": "Hypotension", "C": "Renal scarring", "D": "Ureter stenosis", "E": "Nephrotic syndrome"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 37-year-old man presents to his primary care physician with a chief complaint of diarrhea. The patient states that his symptoms have worsened recently. He works as a farmer and is dressed in tattered and old denim. He lives alone, and this is the first time he has come to town in years. The patient’s diet is mostly dairy products and some meat products. He denies any systemic symptoms and states that diarrhea tends to occur right after a meal. He also claims that at times he struggles to fall asleep, and sometimes he feels he lacks energy. The patient is instructed to avoid consuming dairy products for a week and to return with a report of his symptoms. As you set up the return appointment with this patient you notice that he is rather emotionless. He also states that he lacks anybody that he can list as an emergency contact so he leaves that section of his medical forms blank. What is the most likely diagnosis?", "answer": "Schizoid personality disorder", "options": {"A": "Antisocial personality disorder", "B": "Avoidant personality disorder", "C": "Major depressive disorder", "D": "Schizoid personality disorder", "E": "Schizotypal personality disorder"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 77-year-old man presents to the emergency department with a change in his mental status. The patient’s daughter states that he can cook and clean up after himself and only needs help paying bills. Yesterday the patient seemed fine; however, this morning she noticed that he struggled to perform simple tasks and was forgetful while cooking, leaving the stove on. They recently returned from a trip to Mexico and admit to drinking unfiltered water and eating local cuisines while abroad. The patient has a past medical history of hypertension and diabetes. His temperature is 97.5°F (36.4°C), blood pressure is 187/118 mmHg, pulse is 90/min, respirations are 16/min, and oxygen saturation is 100% on room air. Which of the following is the most likely diagnosis?", "answer": "Vascular dementia", "options": {"A": "Alzheimer dementia", "B": "Frontotemporal dementia", "C": "Lewy body dementia", "D": "Normal pressure hydrocephalus", "E": "Vascular dementia"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 65-year-old male with a past medical history of left ventricular hypertrophy presents to the emergency room because of a history of progressive shortness of breath and a cough productive of frothy pink sputum. Physical examination reveals crackles at the lung bases bilaterally. The patient denies fever, chills, or any recent infection. A radiograph of the chest shows septal lines and areas of opacification in both lung fields (see image).\nWhich of the following most likely accounts for this patient’s dyspnea?", "answer": "Alveolar and interstitial fluid accumulation", "options": {"A": "Obstruction of blood flow through pulmonary arteries", "B": "Destruction of interalveolar septa", "C": "Excess mucous production in bronchiolar epithelium", "D": "A collection of air in the pleural space", "E": "Alveolar and interstitial fluid accumulation"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 42-year-old man is brought to the emergency department because of several episodes of black, tarlike stool and lightheadedness over the past couple of days. He underwent an appendectomy at the age of 16. He has hypertension and tension headaches. He drinks 4 beers daily. Current medications include amlodipine and naproxen. His temperature is 36.7°C (98°F), pulse is 100/min, and his blood pressure is 100/70 mm Hg. The lungs are clear to auscultation bilaterally. The abdomen is soft, nondistended, and nontender. The liver is palpated 3 cm below the right costal margin. His hemoglobin concentration is 10 g/dL. Intravenous fluid resuscitation is begun. An esophagogastroduodenoscopy is performed, which does not show bleeding. Which of the following is the most appropriate next step in management?", "answer": "Colonoscopy", "options": {"A": "Double-balloon enteroscopy", "B": "Capsule endoscopy", "C": "Colonoscopy", "D": "Laparotomy", "E": "Angiography\n\""}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 68-year-old man comes to the physician because of constipation and decreased appetite during the past several months. In the past 2 weeks, he has also noticed an increasing frequency of urination. He has not had any dysuria or flank pain. He has a history of hypertension, calcium pyrophosphate crystal arthritis, and alcoholic cirrhosis. Current medications include hydrochlorothiazide, rifaximin, lactulose, and naproxen as needed for the joint pain. He quit drinking 5 years ago. He does not smoke cigarettes. His vital signs are within normal limits. Physical examination shows decreased bowel sounds but is otherwise unremarkable. Serum studies show:\nCreatinine 1.1 mg/dL\nCalcium 11.8 mg/dL\nPhosphorus 2.1 mg/dL\nMagnesium 1.6 mg/dL\nTotal protein 6 g/dL\nAlbumin 3.1 g/dL\nAST 53 U/L\nALT 43 U/L\nWhich of the following is the most appropriate next step in diagnosis?\"", "answer": "Serum parathyroid hormone level", "options": {"A": "Serum parathyroid-related protein level", "B": "Urine and serum protein electrophoresis", "C": "Serum parathyroid hormone level", "D": "24-hour urine calcium level", "E": "X-ray of the chest"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 68-year-old African American male presents to his primary care provider complaining of progressively worsening back pain. The pain is localized to the lower back and sometimes wakes him up from sleep. He has a history of hypertension and admits to a 50 pack-year smoking history. Further questioning reveals that he has also experienced fatigue and an unintentional weight loss of 18 pounds over the past year. Laboratory analysis is notable for an elevated alkaline phosphatase. A radiograph of the patient’s spine demonstrates multiple sclerotic lesions in the lumbar vertebral bodies. Which of the following tests would most likely confirm the diagnosis in this patient?", "answer": "Transrectal ultrasound-guided prostate biopsy", "options": {"A": "Renal biopsy", "B": "Serum protein electrophoresis", "C": "Fine needle aspiration of the thyroid", "D": "Transrectal ultrasound-guided prostate biopsy", "E": "Chest radiograph"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 75-year-old man presents to his primary care physician because he has been experiencing increasing muscle and joint pain over the last 3 months. He says that he also feels increasingly fatigued and weak despite no change to his daily routine. His past medical history is significant for an infection when he was 12 years of age that led to 2 months of paralysis and mechanical ventilation through a tracheostomy tube. At the time, he developed the paralysis after 3 days of fever and sore throat. He recalls that he was still able to feel everything and was embarrassed that his daily activities had to be performed for him by caregivers. The most likely cause of this patient's symptoms is associated with which of the following structures?", "answer": "Naked (+) stranded RNA virus", "options": {"A": "DNA virus", "B": "Enveloped (+) stranded RNA virus", "C": "Enveloped (-) stranded RNA virus", "D": "Naked (+) stranded RNA virus", "E": "Naked (-) stranded RNA virus"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 2-year-old boy was rushed to the emergency department in the early morning by his mother because he was unresponsive to deep pain stimuli. The patient’s mother said that he has been suffering from a fever, cough and runny nose for the last 10 days. 2 days ago, they visited a free clinic and received medication. When she gave him the medication yesterday, the patient had 3 episodes of vomiting and his condition rapidly worsened. This morning, the patient did not wake up, even after multiple attempts. On physical examination, the patient is febrile, hypotensive, and tachycardic. Peripheral pulses are 1+, and his extremities are pale and cool to touch. Pupils are equal and slowly reactive to light. Significant hepatomegaly is noted. Which of the following is the most likely etiology of this patient’s symptoms?", "answer": "Decrease in beta-oxidation", "options": {"A": "Decrease in electron transport chain", "B": "Decrease in beta-oxidation", "C": "Increase in gluconeogenesis", "D": "Increase in beta-oxidation", "E": "Increase in glycolysis"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 24-year-old patient presents to your gastroenterology practice on a referral from her primary care provider. The patient has been experiencing postprandial bloating and abdominal pain for one year. Symptoms occur following the ingestion of milk products. Which of the following drugs has a mechanism of action that is similar to the pathophysiology of this patient's disease?", "answer": "Magnesium hydroxide", "options": {"A": "Omeprazole", "B": "Bismuth", "C": "Ranitidine", "D": "Octreotide", "E": "Magnesium hydroxide"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "In which location is dimeric IgA most likely to be found in highest concentrations?", "answer": "Colostrum", "options": {"A": "Colostrum", "B": "Blood from the fetus", "C": "Blood from the mother", "D": "Fetal bone marrow", "E": "Fetal thymus"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 25-year-old man presents to the ER after a street fight. His girlfriend reports that he was struck with a bat in the head. After the initial hit, she reported that he briefly lost consciousness but then was normal for several hours. Since then, he has been rapidly decompensating. He is grabbing his head in pain and his mental status is altered. Vital signs are stable. Neurological exam reveals that his right pupil is dilated and his right lid is drooping. If this patient's symptoms are allowed to progress without intervention, which of the following would be expected to occur?", "answer": "Right sided hemiparesis", "options": {"A": "Right sided hemiparesis", "B": "Left sided hemiparesis", "C": "Down and in gaze of the right pupil", "D": "Right sided homonymous hemianopsia.", "E": "Right eye with an inability to abduct"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 7-year-old girl is brought to the emergency department because of diffuse abdominal pain and multiple episodes of vomiting for 2 hours. She started developing fever, headache, and neck pain 3 days ago. On arrival, she is unresponsive. Her temperature is 40.3°C (104.5°F) and palpable blood pressure is 45 mm Hg. Physical examination shows diffuse purpuric skin lesions. In spite of all appropriate therapy, she dies shortly thereafter. Autopsy shows massive parenchymal hemorrhage of the adrenal glands. Which of the following was the portal of entry for the most likely causal organism?", "answer": "Nasopharynx", "options": {"A": "Nasopharynx", "B": "Genital mucosa", "C": "Choroid plexus", "D": "Gastrointestinal tract", "E": "Skin"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 50-year-old female comes to the emergency department with sudden onset left-sided calf pain starting 20 minutes ago. Her past medical history is notable for diabetes, hypertension, and chronic atrial fibrillation controlled on an anti-arrhythmic. Upon arrival to the emergency department, her blood pressure is 150/91 mmHg, pulse is 100/min, and respirations of 22/min. Examination of the leg reveals a pale left calf with diminished dorsalis pedis and posterior tibial pulses. Prompt intervention relieves the patient’s symptoms. Which of the following, if seen microscopically, would indicate that her calf myocytes are more likely to recover without permanent damage?", "answer": "Cellular swelling", "options": {"A": "Cellular swelling", "B": "Mitochondrial vacuolization", "C": "Nuclear pyknosis", "D": "Plasma membrane damage", "E": "Fragmented cells and debris"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 56-year-old man comes to the physician because of progressive worsening of vision in both his eyes over the past 6 months. He reports that he first noticed some blurring of his vision and glare in the evenings, which have both gotten worse in this period. He works as a tower crane operator and spends most of his day outdoors. Ophthalmologic examination shows visual acuity of 20/100 in both eyes. A photograph of the eye is shown. Damage to which of the following structures is most likely responsible for this patient's current symptoms?", "answer": "Lens", "options": {"A": "Aqueous humor", "B": "Cornea", "C": "Vitreous body", "D": "Lens", "E": "Retina"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 25-year-old man presents to the clinic with the complaint of yellow discoloration of his skin. He reports that the discoloration appeared gradually over the past 5 days. He does not have any other complaints. He never had similar symptoms before. Past medical history is only significant for a recent flu infection that was so bad that he missed work for a week. Physical exam is significant for yellow sclera and slight yellowish discoloration of the skin over the face and neck. Liver function tests reveal:\nTotal bilirubin level 5 mg/dL\nDirect bilirubin level 0.4 mg/dL\nAspartate aminotransferase (AST) 25 U/L\nAlanine aminotransferase (ALT) 15 U/L\nWhat is the most likely pathology giving rise to this patient’s condition?", "answer": "Decreased conjugation of bilirubin by uridine-diphosphate glucuronyltransferase", "options": {"A": "Decreased hepatic uptake of unconjugated bilirubin", "B": "Decreased conjugation of bilirubin by uridine-diphosphate glucuronyltransferase", "C": "Bile duct obstruction", "D": "Hemolysis", "E": "Decreased transport of bile into the bile canaliculi"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 17-year-old girl is brought to the physician by her father because of concerns about her behavior. She worries excessively about her weight and body image, and has frequent diarrhea. She is 170 cm (5 ft 7 in) tall and weighs 63.5 kg (140 lb); BMI is 22 kg/m2. She appears anxious but well. Vital signs are within normal limits. Physical examination shows calluses on the knuckles of her right hand. Further evaluation of this patient is most likely to show which of the following findings?", "answer": "Parotid gland swelling", "options": {"A": "Lanugo body hair", "B": "Parotid gland swelling", "C": "Elevated blood pressure", "D": "Right upper quadrant tenderness", "E": "Jugular venous distention"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 36-year-old woman comes to the emergency department because of left wrist pain and swelling that started immediately after a fall. She was walking her dog when the dog abruptly pulled away, causing her to fall forward onto both hands. Physical examination shows left wrist pain with pinching and grasping, moderate swelling, and mild tenderness. Her left thumb is placed in a thumb immobilization splint. An x-ray of the wrist 2 days later is shown. The most likely cause of these findings is a fracture of which of the following bones?", "answer": "Scaphoid", "options": {"A": "Scaphoid", "B": "Ulna", "C": "Radius", "D": "Lunate", "E": "Hamate"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 2200-g (4-lb 14-oz) newborn is delivered at term to a 37-year-old primigravid woman. Apgar scores are 6 and 8 at 1 and 5 minutes, respectively. Examination in the delivery room shows that he is at the 2nd percentile for head circumference and at the 10th percentile for length. He has a small jaw, small eyes, and low-set ears. There is a keyhole-shaped defect in the iris of the left eye. He has seven fingers on each hand. There is an opening in the roof of the mouth extending into the soft and hard palate bilaterally. Cleft lip and cleft palate are present. A 3/6 holosystolic murmur is heard at the left lower sternal border. The heels are prominent, with convex-shaped deformity of the plantar surface of the feet. Which of the following is the most likely cause of these findings?", "answer": "Trisomy 13", "options": {"A": "Fragile X syndrome", "B": "Trisomy 21", "C": "Trisomy 18", "D": "Fetal alcohol syndrome", "E": "Trisomy 13"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 55-year-old woman is rushed to the emergency department after being found lying unconscious in a burning house by a firefighter. No history can be obtained. Her vital signs include pulse 130/min and respirations 16/min. Physical examination reveals soot all over her face. Scattered wheezes can be heard on auscultation of the chest. A thorough survey of the body shows no evidence of any burn injuries. Which of the following changes in the oxygen-hemoglobin curve would most likely be expected in this patient?", "answer": "The curve would be shifted left due to an increased oxygen binding affinity by hemoglobin.", "options": {"A": "The curve would be shifted left due to an increased oxygen binding affinity by hemoglobin.", "B": "The curve would be shifted left due to metabolic acidosis in peripheral tissues.", "C": "The curve would be unchanged because all the hemoglobin molecules are bound to a gas molecule.", "D": "The curve would be unchanged because the partial pressure of oxygen is unchanged.", "E": "The curve would be shifted right due to decreased hemoglobin affinity for oxygen."}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 73-year-old man with a past medical history significant for high blood pressure, hypothyroidism, and diabetes presents to the outpatient clinic. He complains of joint pain, muscle pain, and fatigue that has been present for the last several weeks. On examination, you notice a butterfly-shaped rash across the bridge of his nose and cheeks. He has a blood pressure of 124/72 mm Hg and heart rate of 64/min. Of the following, which medication is most likely responsible for his presentation?", "answer": "Hydralazine", "options": {"A": "Verapamil", "B": "Clonidine", "C": "Labetalol", "D": "Hydralazine", "E": "Terazosin"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 65-year-old woman with a 6-month history of acute promyelocytic leukemia managed with all-trans-retinoic acid presents with severe abdominal pain, nausea, vomiting, and bloody urine. The patient states her symptoms onset acutely a few hours ago and has not improved. She describes the pain as severe, sharp and stabbing in character, and diffusely localized to the umbilical region, accompanied by nausea and vomiting. The patient also states that she noticed blood in her urine last time she urinated. No additional significant past medical history. Her vitals signs include: temperature 37.0°C (98.6°F), blood pressure 95/75 mm Hg, pulse 115/min, respiratory rate 23/min, and oxygen saturation 99% on room air. On physical examination, the patient is ill-appearing and in severe distress. The cardiac exam is normal. Lungs are clear to auscultation. The abdomen is severely tender and out of proportion with physical exam findings. There are diffuse petechiae present over the entire body. Laboratory results are pending. A peripheral blood smear is shown in the exhibit. A contrast CT of the abdomen shows findings consistent with acute mesenteric ischemia. Which of the following set of laboratory findings would most likely be seen in this patient?", "answer": "PT: ↑ | PTT ↑ | Bleeding time: ↑ | Fibrin split products: ↑ | D-dimer: ↑| Fibrinogen: ↓ | Platelet count: ↓", "options": {"A": "PT: ↑ | PTT ↑ | Bleeding time: ↓ | Fibrin split products: ↑ | D-dimer: ↑| Fibrinogen: ↓ | Platelet count: ↓", "B": "PT: ↑ | PTT ↑ | Bleeding time: ↑ | Fibrin split products: ↑ | D-dimer: ↑| Fibrinogen: ↑ | Platelet count: ↓", "C": "PT: ↓ | PTT ↓ | Bleeding time: ↑ | Fibrin split products: ↑ | D-dimer: ↑| Fibrinogen: ↓ | Platelet count: ↓", "D": "PT: ↑ | PTT ↑ | Bleeding time: ↑ | Fibrin split products: ↑ | D-dimer: ↑| Fibrinogen: ↓ | Platelet count: ↓", "E": "PT: ↓ | PTT ↓ | Bleeding time: ↓ | Fibrin split products: ↓ | D-dimer: ↓| Fibrinogen: ↓ | Platelet count: ↓"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 32-year-old woman comes to the physician because of a throbbing left-sided headache that started 3 hours ago. Two hours ago, she took ibuprofen with no relief. She has been vomiting every 20 minutes since the start of the headache. She reports that she could not see very well for a few minutes this morning. A similar episode occurred last week. She is otherwise healthy and has recently started taking an oral contraceptive. Her vital signs are within normal limits. Physical examination shows no abnormalities except mild sensitivity to light. Visual acuity is 20/20. Which of the following is the most appropriate initial pharmacotherapy in this patient?", "answer": "Intravenous prochlorperazine", "options": {"A": "Intranasal dihydroergotamine and subcutaneous sumatriptan", "B": "Oral tramadol", "C": "Intravenous prochlorperazine", "D": "Oral propranolol", "E": "Oral ketorolac and oral ergotamine\n\""}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 66-year-old man presents with palpitation, syncope, and difficulty breathing. He has a past medical history of stroke and his current medications include warfarin. Physical examination is unremarkable. An ECG is performed and shows ventricular tachycardia. The patient is treated successfully with amiodarone. At the time of discharge, his medications include warfarin and amiodarone, and he is cautioned that his PT might be prolonged. Which of the following mechanisms best explains the effect of amiodarone on the coagulation profile of this patient?", "answer": "Amiodarone inhibits CYP2C9 leading to an increased risk of bleeding", "options": {"A": "Amiodarone induces CYP3A4 leading to a decreased effectiveness of warfarin", "B": "Amiodarone inhibits CYP2C9 leading to an increased risk of bleeding", "C": "Amiodarone causes hepatotoxicity which requires monitoring of the prothrombin time", "D": "Inorganic iodine from amiodarone decreases the effectiveness of warfarin", "E": "Amiodarone decreases the renal tubular secretion of warfarin leading to an increased risk of bleeding"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 55-year-old woman presents to the emergency department with recent onset confusion and photophobia. Upon questioning her husband, you discover the patient has been sick over the past week with fevers and productive sputum. Her vital signs are Temperature 102.6 Pulse 80 Respirations 18 Blood Pressure 110/70. The physical exam is significant for lethargy and nuchal rigidity. A lumbar puncture is performed and demonstrates cloudy fluid with an opening pressure of 35 cm H20, cell count of 1500 cells/uL (neutrophil predominant), protein level of 50 mg/dL and glucose of 30 mg/dL. Computed tomography scan demonstrates no space-occupying lesions. What is the most appropriate initial treatment for this patient?", "answer": "Vancomycin, ceftriaxone, ampicillin and dexamethasone", "options": {"A": "Acyclovir", "B": "Supportive treatment, no antibiotics", "C": "Ceftriaxone and dexamethasone", "D": "Vancomycin, ceftriaxone, ampicillin and dexamethasone", "E": "Vancomycin, ceftriaxone and ampicillin"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 58-year-old male presents to his primary care physician complaining of a painless bump on his penis. He first noticed the lesion 1 year ago but was too embarrassed to mention the issue at his last annual physical exam. The lesion has since grown in size and has recently become more erythematous. He has hypertension treated with lisinopril. At age 45, he was successfully treated for phimosis with a steroid cream. He first engaged in sexual intercourse at age 14 and has had “too many sexual partners to count” in his lifetime. He smoked one pack of cigarettes daily for 30 years but quit 10 years ago. He drinks one alcoholic beverage daily. Physical examination shows a nontender 5 mm x 5 mm ulcerated lesion with an erythematous base on the dorsum of the glans. There is no inguinal lymphadenopathy. Excisional biopsy of the lesion is performed. Which of the following pathological findings is most likely to be seen on the biopsy specimen?", "answer": "Atypical squamous cells with varying degrees of mitotic activity", "options": {"A": "Atypical squamous cells with varying degrees of mitotic activity", "B": "Spirochetes on dark-field microscopy", "C": "Nonspecific inflammatory features with C. trachomatis amplification on PCR", "D": "Multinucleated giant cells on Tzanck smear", "E": "Safety pin-shaped intracellular inclusions that appear purple on Giemsa stain"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 54-year-old man comes to the physician for a follow-up appointment. Three weeks ago he underwent emergent cardiac catheterization because of a myocardial infarction and had to stay at the hospital longer than expected because of decreased kidney function. He says his symptoms have since improved greatly and he now produces even more urine than before the procedure. His serum creatinine concentration is 1.6 mg/dL and blood urea nitrogen concentration is 20 mg/dL.This patient is at increased risk for which of the following complications?", "answer": "Hypokalemia", "options": {"A": "Hypermagnesemia", "B": "Metabolic alkalosis", "C": "Hypernatremia", "D": "Hypokalemia", "E": "Hyporeninemia"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 35-year-old woman visits her primary care provider with complaints of easy fatigability, breathlessness on exertion, and altered sensations in her lower limbs. Past medical history is positive for hypertension. She takes hydrochlorothiazide and lisinopril, ethinyl estradiol-progestin, and a multivitamin every day. Family history is noncontributory. She drinks alcohol almost every day and smokes cigarettes when she drinks. Today her heart rate is 95/min, respiratory rate is 17/min, blood pressure is 130/92 mm Hg, and temperature of 37.0°C (98.6°F). Overall, she has marked pallor with slight bluing of her lips and distal fingertips. Her heart has a regular rate and rhythm and her lungs are clear to auscultation bilaterally. Additionally, she has loss of touch, and vibration sense in both of her lower limbs. Her CBC is as follows:\nHemoglobin 8.0 g/dL\nMCV 112 fL\nWBC 2,500/mm3\nPlatelets 95,000/mm3\nWhat is the most likely diagnosis?", "answer": "Vitamin B12 deficiency", "options": {"A": "Vitamin B12 deficiency", "B": "Iron deficiency", "C": "Folic acid deficiency", "D": "Vitamin C deficiency", "E": "Vitamin A deficiency"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 40-year-old man is brought by his wife with nausea and vomiting. He had been working for four hours on repairing his car with the garage shutter closed and the car running but did not lose consciousness. The patient’s blood pressure is 120/70 mmHg, respirations are 28/min, pulse is 120/min, and SaO2 is 98% on room air. The patient has no medical history and is not taking any medications. The patient has 1 alcoholic drink/week and does not use any other illicit drugs. Ophthalmologic exam reveals bilateral retinal hemorrhages. The compound responsible for this patient’s clinical presentation has what mechanism of action?", "answer": "Inhibits the electron transport chain", "options": {"A": "Inhibits the electron transport chain", "B": "Interferes with membrane lipid peroxidation", "C": "Inhibits acetylcholine esterase", "D": "Prevents acetylcholine release", "E": "DNA alkylation"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 54-year-old man is hospitalized after a left hemicolectomy for colon cancer. On postoperative day 1, his hemoglobin is noted on routine labs to have dropped overnight from 7.1 g/dL to 5.3 g/dL. The patient does not report feeling any differently. On exam, his temperature is 100.4°F (38.0°C), blood pressure is 102/80 mmHg, pulse is 95/min, and respirations are 14/min. The patient’s urine output in his Foley bag has been 1.0 cc/kg/hr for the last 8 hours. Prior to the operation, the patient had a temperature of 98.8°F (37.1°C), blood pressure of 122/70 mmHg, and a pulse of 65/min. Which of these findings is most concerning regarding the severity of his hypovolemia?", "answer": "Decreased systolic blood pressure", "options": {"A": "Decreased pulse pressure", "B": "Decreased systolic blood pressure", "C": "Increased heart rate", "D": "Increased temperature", "E": "Urine output"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "An obese 45-year-old female presents to the emergency room complaining of abdominal pain. She reports a 4-hour history of severe right upper quadrant pain following a fatty meal. She has a history of multiple similar episodes over the past year. An ultrasound of the right upper quadrant reveals gallstones. Due to the recurrent nature of her disease, she undergoes an elective laparoscopic cholecystectomy. While in the operating room, the surgeons use the laparoscope to visualize a structure connecting the liver to the anterior wall of the abdominal wall. Which of the following embryologic structures eventually ends up within the visualized structure?", "answer": "Umbilical vein", "options": {"A": "Ductus venosus", "B": "Umbilical artery", "C": "Umbilical vein", "D": "Urachus", "E": "Vitelline duct"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 28-year-old woman presents with a recent history of severe headaches. The patient states that the headaches came on gradually about 1 week ago and have steadily worsened. She describes the headaches as severe, diffuse, and frequently causing nausea and vomiting, especially in the mornings. Past medical history is significant for bacterial meningitis, approx. one month ago, that was successfully treated. Current medications are combined oral contraceptives and fluoxetine. A review of systems is significant for fatigue and daytime sleepiness. Family history is significant for her mother and aunt who suffer from migraines with aura. Her temperature is 37.0°C (98.6°F), the blood pressure is 110/70 mm Hg, the pulse is 70/min, the respiratory rate is 16/min, and the oxygen saturation is 99% on room air. The cardiac exam is normal. Lungs are clear to auscultation. The neurological exam is normal. The ophthalmic exam reveals the indistinct margins of the optic disc, bilaterally. Which of the following is the most likely cause of the headaches in this patient?", "answer": "Hydrocephalus", "options": {"A": "Genetics", "B": "Hydrocephalus", "C": "Intracranial mass", "D": "Trigeminal neuralgia", "E": "Infection"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 72-year-old presents to the Emergency Room with hemoptysis. He has smoked 1 pack of cigarettes a day for the past 30 years. Physical examination of the face is shown in Image A and is accompanied by left upper extremity edema. Of the following, which is the most likely cause of the patient’s symptoms:", "answer": "Superior sulcus tumor", "options": {"A": "Pleural effusion", "B": "Superior sulcus tumor", "C": "Pulmonary embolus", "D": "Mass in the thoracic region of the spinal cord", "E": "Mass effect obstructing the superior vena cava"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 59-year-old man who was recently diagnosed with renal cell carcinoma comes to the physician for a follow-up evaluation. The physician recommends starting treatment with a chemotherapeutic agent that is also used to treat neovascular age-related macular degeneration. A recent history of which of the following conditions would discourage the use of this drug?", "answer": "Gastrointestinal bleeding", "options": {"A": "Interstitial lung disease", "B": "Chronic kidney disease", "C": "Platinum allergy", "D": "Folate deficiency", "E": "Gastrointestinal bleeding"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 36-year-old woman presents with a persistent cough productive of blood-streaked sputum, night sweats, and weight loss. No significant past medical history. She denies any history of smoking, alcohol consumption, or recreational drug use. She works as a nurse at a local hospital and lives in an apartment with her extended family. Her vital signs are a blood pressure of 100/80 mm Hg, heart rate of 94/min, respiratory rate of 17/min, and temperature of 35.9℃ (96.6℉). Physical examination reveals dullness to percussion and diminished breath sounds over the upper lobe of the left lung. During the discussion regarding the required workup, the patient tells the physician about recent contact with a patient with tuberculosis. She asks the physician not to report her case because she is concerned she will lose her job. Which of the following statements is correct?", "answer": "If this patient is diagnosed with active pulmonary tuberculosis, it should be reported even without the patient’s consent, and the patient should receive isolation and treatment.", "options": {"A": "If this patient is diagnosed with active pulmonary tuberculosis, it should be reported even without the patient’s consent, and the patient should receive isolation and treatment.", "B": "The patient has a right to privacy, so, without her consent, the physician can not report her case even if she is diagnosed with active pulmonary tuberculosis.", "C": "If this patient turns out to have active pulmonary tuberculosis, her case can stay unreported only if her apartment cohabitants do not include children or pregnant women.", "D": "If this patient turns out to have active pulmonary tuberculosis, her case can stay unreported only if she agrees to stay home from work and remain isolated at home for her entire treatment period.", "E": "Only active pulmonary tuberculosis is a reportable disease."}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 33-year-old woman gravida 2, para 1, at 35 weeks gestation is admitted to the hospital with fever and active labor. She reports a 2-day history of fluid leakage from the vagina without pain or vaginal bleeding. Her pregnancy has otherwise been uncomplicated. She has attended many prenatal appointments and followed the physician's advice about screening for diseases, laboratory testing, diet, and exercise. Her previous pregnancy was complicated by a preterm delivery at 34 weeks gestation. The patient reports a 10-pack-year history of smoking before pregnancy and smoked 4 cigarettes daily during pregnancy. At the hospital, her temperature is 39.6°C (103.3°F), blood pressure is 108/60 mm Hg, and pulse is 125/min. Her BMI is 18.2 kg/m2. Uterine palpation reveals tenderness. Cervical examination indicates 100% effacement and 10 cm dilation. Her lungs are clear to auscultation. The baseline fetal heart rate is 180/min. Which of the following is the most appropriate next step in management?", "answer": "Ampicillin and gentamicin", "options": {"A": "Amnioinfusion", "B": "Ampicillin and gentamicin", "C": "Cesarean delivery", "D": "Intravenous betamethasone", "E": "Ritodrine hydrochloride"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 49-year-old man, with a history of alcohol abuse over the last 2 decades, presents with a complaint of epigastric pain for about a year. He previously had one episode of acute pancreatitis for which he was hospitalized. He continued to drink 4–5 beers/day after he was discharged. His appetite is good, but he has a history of weight loss. He also complains of oily and bulky stools. He takes aluminum hydroxide gel and ranitidine for partial pain relief. Vital signs are stable. Routine physical exam and blood work are normal except for mild hypocalcemia. Abdominal CT scan is shown below. Which of the following tests is comparatively less useful in assessing the function of the organ involved in this condition?", "answer": "Serum amylase and lipase levels", "options": {"A": "Secretin stimulation test", "B": "Serum amylase and lipase levels", "C": "Serum trypsin level", "D": "Fecal elastase level", "E": "Magnetic resonance cholangiopancreatography (MRCP)"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 34-year-old woman presents to the office due to a pulmonary embolism confirmed by computed tomography (CT) chest angiogram, which she was recently hospitalized for. She does not have any recent surgical trauma or travel history. She complains of having episodes where her fingers become white and then blue, and they are usually accompanied by pain in the same region. These episodes tend to happen more frequently during winter and have been ongoing for about 2 years now. She also had a spontaneous abortion at 12 weeks of gestation last year. She does not have a family history of venous thromboembolic disease. The vital signs include heart rate 76/min, respiratory rate 18/min, temperature 37.2°C (99.0°F), and blood pressure 120/80 mm Hg. Physical examination is non-contributory. The complete blood count (CBC) results are as follows:\nHemoglobin 14.2 g/dL\nHematocrit 39%\nLeukocyte count 4,950/mm3\nNeutrophils 59%\nBands 3%\nEosinophils 1%\nBasophils 0%\nLymphocytes 31%\nMonocytes 4%\nPlatelet count 120,000/mm3\nThe coagulation test results are as follows:\nPartial thromboplastin time (activated) 56 seconds\nProthrombin time 15 seconds\nReticulocyte count 1.0%\nThrombin time < 2 seconds deviation from control\nWhich of the following diagnostic tests would be the most appropriate?", "answer": "Lupus anticoagulant", "options": {"A": "Antithrombin III", "B": "Protein C", "C": "Factor-V-Leiden", "D": "Lupus anticoagulant", "E": "Protein S"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 36-year-old woman, gravida 3, para 2, at 34 weeks' gestation is brought to the emergency department for the evaluation of continuous, dark, vaginal bleeding that started one hour ago. She also reports severe lower abdominal pain. Her current pregnancy was complicated by preeclampsia. Her first two children were delivered vaginally. Current medications include methyldopa and a multivitamin. Her pulse is 100/min, respirations are 16/min, and blood pressure is 90/60 mm Hg. The abdomen is tender, and hypertonic contractions are felt. There is blood on the vulva and on the medial aspect of both thighs bilaterally. The fetus is in a cephalic presentation. The fetal heart rate is 170/min with several decelerations. Which of the following is the most appropriate next step in the management of this patient?", "answer": "Emergency cesarean delivery", "options": {"A": "Emergency cesarean delivery", "B": "Elective cesarean delivery", "C": "Administration of terbutaline", "D": "Ultrasound", "E": "Administration of oxytocin and normal vaginal birth"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 16-year-old boy is brought to the emergency department because of severe left flank pain and nausea for 3 hours. The pain is colicky and radiates towards his groin. He drinks multiple glasses of iced tea every day. He has had similar episodes of abdominal pain in the past. His maternal uncle has a similar history of abdominal pain. His temperature is 37.1°C (98.8°F), pulse is 103/min, and blood pressure is 108/72 mm Hg. Examination shows a soft and nontender abdomen. Left costovertebral angle tenderness is present. An x-ray of the abdomen shows no abnormalities. A urinary cyanide nitroprusside test is positive. Further evaluation of this patient is most likely to show which of the following?", "answer": "Hexagon-shaped crystals on urinalysis", "options": {"A": "Rhomboid crystals on urinalysis", "B": "Urinary pH of 7.8", "C": "Serum anti-Saccharomyces cerevisiae antibodies", "D": "Proteus mirabilis on urine culture", "E": "Hexagon-shaped crystals on urinalysis"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 57-year-old woman comes to the emergency department because of severe dyspnea, cough, and pleuritic chest pain for 20 minutes. Three weeks ago, she underwent surgery for a total right knee replacement. The patient appears distressed. Her pulse is 112/min, respirations are 24/min, and blood pressure is 88/55 mm Hg. Examination shows jugular venous distention. There is a mildly tender surgical scar on her right knee. A CT scan of the chest is shown. Which of the following is the most appropriate treatment for this patient's condition?", "answer": "Alteplase", "options": {"A": "Endovascular stent-grafting", "B": "Alteplase", "C": "Coronary angioplasty", "D": "Bumetanide", "E": "Pericardiocentesis"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A group of multidisciplinary researchers from a tertiary hospital decides to investigate whether there is an association between splenectomy and pulmonary tuberculosis. From the hospital database, they identify 19,000 patients over the age of 20 with newly diagnosed pulmonary tuberculosis, as well as 72,000 patients without pulmonary tuberculosis for comparison purposes. Both of these groups are matched for age, gender, and an index year when the condition was initially diagnosed. The odds of pulmonary tuberculosis development associated with splenectomy and other comorbidities is estimated. After controlling for all relevant confounders, the results show that splenectomy is associated with a two-fold higher incidence of pulmonary tuberculosis development. There is also a synergistic effect between splenectomy and other comorbid conditions in the development of pulmonary tuberculosis. What type of study has been used by the researchers in this example?", "answer": "Case-control study", "options": {"A": "Cohort study", "B": "Cross-sectional study", "C": "Case-control study", "D": "Ecological study", "E": "Intervention study"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 53-year-old woman presents to the clinic with complaints of fatigue. She reports that over the past several months she has been lethargic and tired. She has gained 10 pounds over the past month but attributes it to her menopause. Her last menstrual period (LMP) was 1 year ago. Past medical history is significant for asthma and seasonal allergies, and medications include a rescue inhaler and cetirizine as need. Review of systems is negative except for cold intolerance and constipation. What is the best next step in evaluating this patient?", "answer": "TSH levels", "options": {"A": "Beta-hCG levels", "B": "FSH levels", "C": "Thyroid peroxidase antibody titer", "D": "TSH levels", "E": "Ultrasound of the neck"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 33-year-old man presents to his primary care physician for fatigue, weight loss, and diffuse pruritus. The patient has a past medical history of multiple admissions for severe abdominal pain and bloody diarrhea as well as several episodes of ascending cholangitis which were successfully treated. He is currently a member of Alcoholics Anonymous. His temperature is 98.2°F (36.8°C), blood pressure is 124/75 mmHg, pulse is 100/min, respirations are 13/min, and oxygen saturation is 99% on room air. Urinalysis is notable only for a dark urine sample with no red blood cells present. A rectal exam reveals pale stool and grossly visible blood. Physical exam is otherwise notable for pruritis, jaundice, and scleral icterus. Which of the following is the most likely underlying diagnosis?", "answer": "Cholangiocarcinoma", "options": {"A": "Acute cholecystitis", "B": "Ascending cholangitis", "C": "Cholangiocarcinoma", "D": "Cirrhosis", "E": "Colon cancer"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 43-year-old female presents with several years of pain and stiffness in her wrists and hands. Her symptoms have been getting progressively worse. She reports that her hands feel stiff for an hour or more after awaking in the morning. She undergoes subsequent testing, and is found to have anti-citrullinated protein antibodies. Her physician is concerned for rheumatoid arthritis, and discusses treatment with a biologic disease-modifying anti-rheumatic agent.\n\nWhich of the following must be done before beginning treatment with a TNF inhibitor?", "answer": "Test for latent mycobacterial infection", "options": {"A": "Confirm diagnosis with a test for rheumatoid factor", "B": "Confirm diagnosis with elevated ESR and CRP", "C": "Test for latent mycobacterial infection", "D": "Obtain a radiograph demonstrating osteophytes", "E": "Obtain an exercise stress test"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 65-year-old man is brought to the emergency department with a complaint of right-sided numbness for 5 hours. The numbness started in the right-side of the face and has progressed to the same side arm and leg within 30 minutes. He denies limb weakness, walking difficulty, vision problem, or vertigo. He had similar symptoms 5 months ago that were resolved within 10 minutes. The past medical history includes type 2 diabetes mellitus, hypertension, dyslipidemia, and hyperuricemia. The medication list includes allopurinol, amlodipine, aspirin, glimepiride, lisinopril, and rosuvastatin. The blood pressure is 165/102 mm Hg, and the rest of the vital signs are within normal limits. On examination, there are no facial droop and slurring of the speech noted. The muscle strength is normal in all 4 limbs with a normal tone and deep tendon reflexes. There is a decreased pinprick sensation and proprioception on the right arm and leg. The gait is normal. The blood sugar is 221 mg/dL. The CT scan of the head is normal. The MRI of the head with diffusion-weighted imaging reveals a 15 mm diffusion restriction in the left thalamus. Which of the following is the most crucial in the development of this patient’s condition?", "answer": "Lipohyalinosis of small penetrating arteries due to chronic hypertension", "options": {"A": "Emboli from deep leg veins with a patent foramen ovale", "B": "Emboli from the left ventricle of the heart", "C": "Leakage of blood from intracranial vessel due to uncontrolled hypertension", "D": "Lipohyalinosis of small penetrating arteries due to chronic hypertension", "E": "Significant stenosis of the left carotid artery"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 23-year-old man presents to a psychiatrist for evaluation of situational anxiety. He reports that he recently started a new job that involves regular public speaking and is very stressed before every public speaking event. He describes developing a rapid heart rate and diaphoresis that interferes with his ability to speak well. He has no past medical history and takes no medications. He does not smoke or drink alcohol. His temperature is 98.6°F (37°C), blood pressure is 110/65 mmHg, pulse is 85/min, and respirations are 17/min. On exam, he is well-appearing and appropriately conversational. He is alert and fully oriented. The patient is prescribed propranolol to take before major public speaking events. Which of the following physiologic changes will occur when the patient takes this medication?", "answer": "Decreased cardiac output and increased peripheral resistance", "options": {"A": "Decreased cardiac output and decreased peripheral resistance", "B": "Decreased cardiac output and increased peripheral resistance", "C": "Increased cardiac output and decreased peripheral resistance", "D": "Increased cardiac output and increased peripheral resistance", "E": "Normal cardiac output and normal peripheral resistance"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 69-year-old woman is brought into the emergency room by family members after they noted that she had become increasingly lethargic over the past 3 days. Her temperature is 39.5°C (103.1°F), the blood pressure is 75/40 mm Hg, the heart rate 130/min, the respiratory rate 24/min, and the oxygen saturation is 89% on room air. On examination, she is severely ill, drowsy, and unable to speak. Her skin is warm to the touch. White blood cell count is 15,000/mm3 and her urinalysis is positive for nitrites and leukocyte esterase. Which of the following is the best initial step in the management of this patient's condition?", "answer": "Assessment of airway, breathing, and circulation", "options": {"A": "Intramuscular adrenaline", "B": "Intravenous hydrocortisone", "C": "Infusion of hydroxyethyl starch (HES) solutions", "D": "Assessment of airway, breathing, and circulation", "E": "Intravenous noradrenaline"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 28-year-old G2P1 woman at 29 weeks gestation presents to the obstetrician after noticing red spots on her undergarments over the past week. Her vaginal bleeding has not been painful; however, she is concerned that it has persisted. Her previous child was born by cesarean section and she is currently taking folate and a multivitamin. She endorses feeling fetal movements. Her temperature is 98.9°F (37.2°C), blood pressure is 120/84 mmHg, pulse is 88/min, respirations are 17/min, and oxygen saturation is 99% on room air. Physical exam is notable for a gravid uterus and non-tender abdomen. Speculum exam reveals a closed cervical os and a small amount of blood. Which of the following is the most likely diagnosis?", "answer": "Placenta previa", "options": {"A": "Placenta percreta", "B": "Placenta previa", "C": "Placental abruption", "D": "Uterine rupture", "E": "Vasa previa"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 57-year-old woman comes to the emergency department 1 hour after experiencing a distressing 10-minute episode of stuttering during a business meeting. She has hypertension. She has smoked 2 packs of cigarettes daily for 30 years. Current medications include fosinopril and hydrochlorothiazide. Her temperature is 37°C (98.6°F), pulse is 90/min, respirations are 16/min, and blood pressure is 134/88 mm Hg. She is oriented to person, place, and time. Her speech is clear. When she is asked to hold both arms fully extended at shoulder level with palms upwards and eyes closed, her right palm turns inwards and downwards. Which of the following is the most likely cause of this patient's physical findings?", "answer": "Upper motor neuron lesion", "options": {"A": "Cerebellar lesion", "B": "Posterior column lesion", "C": "Inferior frontal gyrus lesion", "D": "Upper motor neuron lesion", "E": "Thalamus lesion"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 40-year-old man comes to the physician because of a 5-kg (11-lb) weight loss over the past month and easy bruising. He has not changed his diet significantly. He also noticed that his arms now bruise more easily. He appears pale. His pulse is 70/min, his blood pressure is 125/75 mm Hg, and his temperature is 38°C (100.4°F). Examination shows a palm-sized hematoma on his right arm. His spleen is palpable 5 cm below the costal margin. His liver is enlarged. Laboratory results show:\nLeukocytes 10,500/mm3\nHemoglobin 10.2 g/dL\nPlatelets 52,000/mm3\nFibrinogen 110 mg/dL (Reference: 150-400 mg/dL)\nCytogenetic analysis shows leukocytes with a reciprocal translocation of chromosomes 15 and 17. Which of the following is the most appropriate treatment for this patient at this time?\"", "answer": "All-trans retinoic acid", "options": {"A": "Rituximab", "B": "Cyclophosphamide", "C": "All-trans retinoic acid", "D": "Cryoprecipitate transfusion", "E": "Imatinib"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "At a routine exam, a 68-year-old female patient is discovered to have a serum calcium level of 11.5 mg/dL. Follow-up laboratory tests show a high parathyroid hormone with low phosphorus and mildly elevated alkaline phosphatase. 24-hour urine calcium level is elevated. Review of symptoms includes complaints of fatigue, constipation, and diffuse bone pain for which she takes vitamin D. Past medical history is significant for type 2 diabetes mellitus for 25 years and essential hypertension for 15 years. The patient has a history of kidney stones. Family history is irrelevant. Which of the following is the most likely etiology of this patient's condition?", "answer": "Solitary parathyroid adenoma", "options": {"A": "Vitamin D intoxication", "B": "Familial hypocalciuric hypercalcaemia", "C": "Solitary parathyroid adenoma", "D": "Thyrotoxicosis", "E": "Humoral hypercalcemia of malignancy"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 27-year-old man and his wife present to an infertility clinic for evaluation after they tried unsuccessfully to conceive for 2 years. He has no prior medical history and does not currently take any medications. On evaluation, he is found to have long extremities and gynecomastia. In addition, he has testicular atrophy and very little body hair, which is distributed primarily in the pubic region. Further analysis reveals azoospermia, and appropriate tests confirming the diagnosis are performed. The couple is told about the cause of their inability to conceive and given further options to pursue. Which of the following is associated with the pathophysiology underlying this patient's disorder?", "answer": "Increased aromatase activity", "options": {"A": "Abnormal signaling through androgen receptors", "B": "Abnormal conversion of testosterone", "C": "Defective migration of hormone producing neurons", "D": "Increased aromatase activity", "E": "Increased production of prolactin"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 32-year-old GP2 presents to an outpatient clinic for a routine gynecologic examination. The patient appears well, although she mentions that during the past 6 months she has noticed small amounts of vaginal bleeding in the middle of her menstrual cycles. Her last pregnancy was 3 years ago. Her subsequent menstrual cycles have been regular, lasting about 2–3 days. She mentions that she is up to date with her Pap smear; all of her Pap smears have been normal. She denies any recent travel or history of trauma. The patient is sexually active with her husband and they use condoms consistently. She does not smoke, drinks alcohol occasionally, and has never used illicit drugs. The physical examination is essentially normal. An ultrasound reveals a fleshy mass with a pedunculated stalk deep in the cervical canal. The uterine lining measures 5 mm in thickness and is homogeneous. Multiple small leiomyomas are also observed. The patient is otherwise asymptomatic and has no other complaints. The rest of the physical examination is unremarkable. Which of the following is the next best step in management?", "answer": "Removal of the lesion with a ring forceps", "options": {"A": "No further intervention with follow-up in 6 months", "B": "Electrocautery and cryofreezing", "C": "Cervical brush biopsy", "D": "Removal of the lesion with a ring forceps", "E": "Administration of antibiotics"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "An 11-year-old girl presents to her pediatrician with complaints of headache and rapid leg fatigue with exercise. Her vital signs are: HR 77, BP in left arm 155/100, RR 14, SpO2 100%, T 37.0 C. On palpation, her left dorsalis pedis pulse is delayed as compared to her left radial pulse. Her lower extremities feel slightly cool. Blood pressure obtained on the left lower extremity is 120/80. Which of the following is the most likely underlying pathology?", "answer": "Coarctation of the aorta", "options": {"A": "Peripheral arterial disease", "B": "Vasospasm", "C": "Coarctation of the aorta", "D": "Tetralogy of Fallot", "E": "Aortic stenosis"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 34-year-old woman comes to the gynecologist complaining of vaginal swelling and discomfort. She states that over the past 2 weeks she has noticed swelling of her right labia. The swelling continued to grow in size and now causes her discomfort when walking. She denies abnormal discharge or bleeding from the swelling or from the vulva. She normally shaves the area, but with the recent pain, she has been unable to. She denies any history of known trauma. The patient is relatively healthy and takes only a multivitamin. She never received the vaccine for human papillomavirus (HPV). On physical exam, there is a fluctuant, swelling of the right labia, most prominently at the posterior vestibule. Which of the following is the most likely diagnosis?", "answer": "Bartholin gland cyst", "options": {"A": "Bartholin gland cyst", "B": "Condyloma acuminata", "C": "Folliculitis", "D": "Granuloma inguinale", "E": "Vulvar cancer"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 4-month-old boy is brought to the physician because of noisy breathing for 2 months that has progressively become louder. The noisy breathing improves when he is in the prone position. It is worse when he is agitated, feeding, or lying on his back. He was born at term and has been healthy since. His temperature is 37.1°C (98.8°F), pulse is 120/min, and respirations are 50/min. Pulse oximetry on room air shows an oxygen saturation of 98%. Examination shows inspiratory stridor. Which of the following is the most appropriate treatment?", "answer": "Observation", "options": {"A": "Dexamethasone therapy", "B": "Observation", "C": "Surgical division", "D": "Ceftriaxone therapy", "E": "Supraglottoplasty"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 16-year-old girl comes to the physician with a 4-day history of painful vulvar lesions, generalized fatigue, and malaise. During this period, she has also had dysuria. She is sexually active with 2 male partners and uses condoms inconsistently. Her immunizations are up-to-date; she completed the vaccination course for human papilloma virus 2 months ago. Her temperature is 38.1°C (100.6°F), pulse is 100/min, respirations are 12/min, and blood pressure is 110/70 mm Hg. Pelvic examination shows several shallow ulcers on an erythematous base over the labia majora and minora. There is bilateral, tender inguinal lymphadenopathy. Which of the following is the most appropriate treatment for this patient's condition?", "answer": "Acyclovir therapy", "options": {"A": "Acyclovir therapy", "B": "Curettage", "C": "Azithromycin therapy", "D": "Doxycycline therapy", "E": "Penicillin therapy"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 57-year-old man comes to the physician because of progressively worsening epigastric pain and 6.8-kg (15-lb) weight loss for the past 2 months. Two weeks ago, he noticed painful, red blotches on the medial aspect of his right calf. He has smoked one pack of cigarettes daily for the last 35 years. He appears thin. Physical examination shows tender erythematous nodules on the right ankle and left antecubital fossa. Endoscopy shows a large mass in the antrum of the stomach. A biopsy specimen of the gastric mass shows disorganized mucin-secreting cells with surrounding fibrosis. These cells most likely originated from which of the following structures?", "answer": "Exocrine ducts in the body of the pancreas", "options": {"A": "Lymphoid tissue in the terminal ileum", "B": "Mature hepatocytes in the liver", "C": "Exocrine ducts in the body of the pancreas", "D": "Squamous epithelium in the proximal esophagus", "E": "Glandular epithelium in the sigmoid colon"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 62-year-old woman comes to the emergency department because of painful and difficult swallowing. Her voice has also become muffled. She has been well until last night and reports having intermittent fevers at home. The patient has smoked a pack of cigarettes a day since age 19 but is otherwise healthy. Her temperature is 39°C (102.2°F), blood pressure is 142/93 Hg/mm, heart rate is 109/min, and respiratory rate is 18/min. On examination, the patient's head is extended and she appears anxious. Her voice is muffled and there is inspiratory stridor. There is tender bilateral cervical lymphadenopathy and pain upon palpation of the hyoid. The remainder of the examination shows no abnormalities. Laboratory studies show a leukocyte count of 18,000/mm3 with 83% neutrophils. Which of the following is the most likely cause of this patient's presentation?", "answer": "Haemophilus influenzae type b", "options": {"A": "Adenovirus", "B": "Pseudomonas aeruginosa", "C": "Corynebacterium diphtheriae", "D": "Parainfluenza virus", "E": "Haemophilus influenzae type b"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 56-year-old woman is brought to the emergency department by her husband 30 minutes after a generalized tonic-clonic seizure. Over the past 3 months, she has had recurrent headaches and worsening early-morning vomiting. She has no personal or family history of a seizure disorder. An MRI of the brain shows a central mass; surgical resection is planned. One day before the surgery, the patient has another generalized seizure and, despite resuscitative efforts, she dies. Gross examination of the brain at autopsy is shown. Which of the following was the most likely cause of this patient's symptoms?", "answer": "Glioblastoma", "options": {"A": "Oligodendroglioma", "B": "Glioblastoma", "C": "Schwannoma", "D": "Brain metastasis", "E": "Meningioma"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 29-year-old woman (gravida 2, para 1) presents at 32 weeks gestation for routine follow-up care. Her previous pregnancy was complicated with preeclampsia, and she delivered at 35 weeks via cesarean delivery. Four years ago, she was diagnosed with arterial hypertension. Prior to pregnancy, she took amlodipine and hydrochlorothiazide; after she found out she was pregnant, she switched to methyldopa. The course of her current pregnancy has been unremarkable with normal laboratory values at each checkup. According to her blood pressure diary, her systolic blood pressure varies between 120 and 130 mm Hg, and her diastolic blood pressure is usually normal. At presentation, the blood pressure is 140/80 mm Hg, heart rate is 76/min, respiratory rate is 15/min, and temperature is 36.9°C (98.4°F). The fetal heart rate is 143/min. Examination shows a 1+ pitting lower leg edema. Dipstick test shows 2+ protein. 24-hour urine assessment demonstrates urinary protein excretion of 1 g/L. Which of the following laboratory values should be assessed next in this patient?", "answer": "Liver transaminases", "options": {"A": "Coagulogram", "B": "Liver transaminases", "C": "Total bilirubin", "D": "Lipidogram", "E": "Urinalysis"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "Following a colonoscopy performed on a 63-year-old man, the gastroenterologist identifies a firm tumor approx. 80 cm (31.4 in) from the entry site. He also performs an endoscopic polypectomy and tattooing at 50 cm (19.6 in) from the entry site. A pathologic report shows a benign polyp. One week later, the surgeon in the operating room is erroneously preparing to perform partial colectomy of the tattooed site. After confirming the patient’s name and before surgery, the surgical team reviews the patient’s history and medical documents orally based on institutional protocols. The surgery resident points out that the resected polyp is benign and the tumor lies 30 cm (11.8 in) distal to the tattooed area. The attending surgeon performs a partial colectomy on the correct site. Which of the following best describes this approach to the prevention of medical errors?", "answer": "Preoperative time-out", "options": {"A": "Closed-loop communication", "B": "Preoperative time-out", "C": "Primordial prevention", "D": "Root cause analysis", "E": "Sentinel event"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 28-year-old G2P1001 presents for a routine obstetric visit in her 36th week of pregnancy. She has a history of type I diabetes controlled by insulin and delivered 1 child by normal spontaneous vaginal delivery 2 years ago. Earlier in this pregnancy, she had 2 episodes of burning with urination and frequent urination. Urinalysis each time confirmed a urinary tract infection, and both urine cultures isolated organisms sensitive to nitrofurantoin. Her symptoms resolved with 10-day courses of nitrofurantoin. She has no complaints today. Urinalysis is positive for leukocyte esterase and nitrites. Which of the following is the best next step in management?", "answer": "Treat with oral nitrofurantion for 10 days then continue for prophylaxis until delivery", "options": {"A": "No treatment", "B": "Admit to the hospital and treat with intravenous ceftriaxone", "C": "Treat with oral trimethroprim-sulfamethoxazole for 10 days then continue for prophylaxis until delivery", "D": "Treat with oral nitrofurantion for 10 days", "E": "Treat with oral nitrofurantion for 10 days then continue for prophylaxis until delivery"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 3-year-old boy is brought to the physician by his parents because of clumsiness and multiple falls over the past 4 months. He started walking at the age of 18 months and could walk up steps by the time he was 27 months old but now struggles to walk at all without assistance. When standing up from a lying position, he crawls onto his knees and slowly walks himself up with his hands. There is bilateral calf enlargement. Analysis of a left calf biopsy specimen from this patient is most likely to show which of the following?", "answer": "Degeneration of muscle fibers with fibrofatty replacement", "options": {"A": "Perivascular inflammation with muscle fiber ischemia and atrophy", "B": "Proliferation of mitochondria within muscle fibers", "C": "Degeneration of muscle fibers with fibrofatty replacement", "D": "Atrophic muscle fibers interspersed among hypertrophic muscle fibers", "E": "Necrotic muscle fibers with lymphocytic infiltrate"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 60-year-old man presented to the hospital with right upper quadrant abdominal pain. He has a history of hepatitis B. He underwent a CT of his abdomen which revealed a large mass (11.3 cm x 7.2 cm in diameter) with a metastatic retroperitoneal lymph node. He was diagnosed with hepatocellular carcinoma and initially received radiotherapy while on the transplant list to prevent local expansion of his malignancy. 3 months after radiotherapy, the patient experienced hematemesis and melena. He was admitted to the emergency department for evaluation. His vitals were: blood pressure 84/56 mmHg, heart rate 92/min, and respiratory rate 20/min. Laboratory evaluation revealed severe anemia with a hemoglobin level of 5.7 g/dL, INR 1.8 and platelets of 68,000 cells/mm3. He received a blood transfusion. An endoscopic examination demonstrated diffuse edematous hyperemic mucosa and multiple hemorrhagic patches with active oozing in the antrum. What is the most likely diagnosis for the lesions seen in endoscopy?", "answer": "Intrinsic apoptotic pathway", "options": {"A": "Intrinsic apoptotic pathway", "B": "Coagulative necrosis", "C": "Overexpression of BcL-2 gene", "D": "Cytotoxic CD8 T cells pathway", "E": "Extrinsic apoptotic pathway"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 49-year-old Caucasian woman presents to your office for elevated blood pressure. She is a nurse and checks her blood pressure regularly while working in the wards. She presents with readings ranging between 163/101 and 156/94 mm Hg. After some research she conducted on her own, she has been exercising and following a low-fat, low-salt diet for the past 3 months. Her past medical history includes laparoscopic cholecystectomy for acute cholecystitis 2 years previously. Her mother and father have hypertension and her father had myocardial infarction at the age of 68 years. She takes no medications and denies smoking. She drinks 3 glasses of wine a week. Her blood pressure in the office after more than 10 minutes of rest was 153/89 mm Hg in her left arm and 145/90 mm Hg in her right arm. A review of her medical record reveals that her blood pressure was 142/92 mm Hg at her visit 1 year ago. Which of the following is the best next step in management?", "answer": "Blood glucose", "options": {"A": "Liver function tests", "B": "Urine microalbumin", "C": "Hemoglobin A1C", "D": "Blood glucose", "E": "Exercise stress test"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 55-year-old man presents to his primary care physician for back pain. The patient states that his back pain is worse in the morning and improves with certain activities. He does not experience pain when cycling but notices the pain when standing or walking. 2 months prior to presentation he was lifting heavy boxes and furniture into his daughter's new home. He is requesting pain medication and a doctor's note to take off work for the week as his symptoms are disrupting his life. Which of the following is most likely to be seen in this patient?", "answer": "Narrowing of the lumbar spinal canal on MRI", "options": {"A": "Bamboo appearance of the spine on radiography", "B": "Herniated nucleus pulposus on MRI", "C": "Muscular tenderness with perispinal palpation", "D": "Multiple doctors visits for other unrelated problems", "E": "Narrowing of the lumbar spinal canal on MRI"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 75-year-old man presents to the emergency department from his doctor’s office with a 2-day history of urinary hesitancy, fever, and chills. He additionally notes that he has been getting up frequently during the night to urinate. For the last 2 years, it has taken him longer than usual to initiate urination and his stream has gotten weaker. He has a history of hypertension for which he takes losartan. His blood pressure is 128/84 mm Hg, heart rate is 84/min, respiratory rate is 14/min, and temperature is 38.2°C (100.8°F). No costovertebral angle tenderness is present on physical examination. The patient declines rectal examination. Significant laboratory results are as follows:\nWBC 15.2 x  10°/L\nHemoglobin 13.4 g/dL\nPlatelets 185 x 109/L\nProstate-specific antigen (PSA) 10 ng/mL\nWhat is the most likely cause of the patient’s symptoms?", "answer": "Prostatitis", "options": {"A": "Prostate cancer", "B": "Urinary tract infection", "C": "Pyelonephritis", "D": "Nephrolithiasis", "E": "Prostatitis"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 6-year-old boy is brought to the physician for evaluation of bilateral erythematous skin lesions on the flexures of the elbows and knees. He has been scratching the areas frequently. He has had similar lesions intermittently for the last 2 years. A photograph of the lesions on the back of the knees is shown. This patient's skin lesions are most likely associated with which of the following?", "answer": "Reversible decrease in FEV1/FVC ratio", "options": {"A": "Reversible decrease in FEV1/FVC ratio", "B": "Glomerular subepithelial immune complex deposition", "C": "IgA anti-tissue transglutaminase antibodies", "D": "Hepatocyte infection with hepatitis C virus", "E": "Pencil-in-cup deformity of the fingers"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "An important step in the formation of thyroid hormones is the formation of I2 via oxidation of I-. Which of the following molecules is responsible for this reaction?", "answer": "Thyroid peroxidase", "options": {"A": "Thyroid deiodinase", "B": "Thyroid peroxidase", "C": "5'-deiodinase", "D": "Perchlorate", "E": "Propylthiouracil"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 29-year-old woman presents to her primary care provider for a normal check-up at the prompting of her mother. When asked how she is doing, she replies that she feels depressed. Upon further questioning, she states that she feels “worthless” now that her ex-boyfriend left her 2 days ago. She has been sitting in his bed all day trying to call him but he is not answering her calls. She says that she will never find another man like him and feels like she should just “disappear” rather than continue living without him. She also reports that she can hear his voice when he’s not around, especially at night before she goes to bed. She denies having any other friends and has some social anxiety, particularly in large groups of people. A review of her medical record indicates that she has endured several episodes of verbal and physical abuse from her prior relationships which she suggested “were all her fault.” She has had 4 prior serious relationships and reports that she has not been single for more than a few days in the last 10 years. On exam, she is unkempt with poor self-care. This patient’s history is most consistent with which of the following conditions?", "answer": "Dependent personality disorder", "options": {"A": "Avoidant personality disorder", "B": "Borderline personality disorder", "C": "Dependent personality disorder", "D": "Histrionic personality disorder", "E": "Paranoid personality disorder"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 65-year-old man presents to the emergency department with confusion and chest pain. He states his symptoms started after he landed on a return flight from Brazil. Since then, the patient states that he feels anxious, short of breath, and has pleuritic chest pain. The patient has a past medical history of diabetes and chronic kidney disease. His medications include insulin, lisinopril, aspirin, and atorvastatin. His temperature is 101°F (38.3°C), blood pressure is 154/94 mmHg, pulse is 90/min, respirations are 17/min, and oxygen saturation is 96% on room air. Physical exam is notable for a confused man. The patient’s laboratory studies are ordered as seen below.\n\nSerum:\nNa+: 140 mEq/L\nCl-: 103 mEq/L\nK+: 5.3 mEq/L\nHCO3-: 25 mEq/L\nBUN: 33 mg/dL\nGlucose: 168 mg/dL\nCreatinine: 1.8 mg/dL\nCa2+: 10.0 mg/dL\nTroponin: < 0.05 mcg/L\n\nA chest CT angiogram, an echocardiogram (ECG), and a second troponin are ordered and are all unremarkable. The patient’s chest pain resolves with diazepam. A lumbar puncture is performed and based on the results the patient is subsequently started on acyclovir. Which of the following is the best next step in management?", "answer": "Bolus of IV fluids", "options": {"A": "Bolus of IV fluids", "B": "Calcium gluconate", "C": "Cardiac catheterization", "D": "Hemodialysis", "E": "No further interventions needed"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 52-year-old homosexual man presents to the emergency department because of sudden right loin pain accompanied by nausea and vomiting. He has essential hypertension for 3 years for which he takes bisoprolol. He has a remote history of intravenous drug use. His temperature is 36.9°C (98.4°F), the blood pressure is 137/92 mm Hg, and the pulse is 95/min. Physical examination reveals right flank tenderness and 2+ edema of both legs up to the knees. Doppler ultrasonography shows an enlarged, echogenic right kidney with the absent venous signal. Laboratory results are shown:\nSerum creatinine 2.2 mg/dL\nUrine dipstick 4+ protein\nUrine analysis 20–25 red cells/high power field\nWhich of the following is the most likely underlying etiology of this patient's condition?", "answer": "Membranous nephropathy", "options": {"A": "Acute pyelonephritis", "B": "Kidney stones", "C": "Hypertensive kidney disease", "D": "Membranous nephropathy", "E": "Penile cancer"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 53-year-old woman is brought to the emergency department for a 2-hour history of balance problems. She was gardening when she suddenly felt very dizzy and she quickly called for her husband. When he arrived, she was sitting on the ground, swaying back and forth but overall leaning to the right. When she tried to stand up they found she was very unsteady and unbalanced, so her husband carried her to the car. In the emergency department, while lying in bed, she complains of a room-spinning sensation; when she sits up, she sways to the right. She is unable to walk more than 3 steps without falling. Finger-nose-finger and heel-knee-shin testing are abnormal. She has a past medical history of hypertension, polycystic ovarian syndrome, and type 2 diabetes mellitus. All of her vital signs are all within normal limits. Angiography would most likely show a dissection in which of the following vessels?", "answer": "Vertebral artery", "options": {"A": "Internal carotid artery", "B": "Anterior cerebral artery", "C": "Middle cerebral artery", "D": "Vertebral artery", "E": "Anterior spinal artery"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 65-year-old man with squamous cell carcinoma of the lung presents with a sodium of 118 and an altered mental status. He is started on 3% normal saline over the next several hours. The patient’s mental status improves and and a repeat sodium six hours later is 129. Three days after treatment he demonstrates quadriparesis and dysarthria. Which of the following best describes this cause of the patients symptoms after treatment?", "answer": "Osmotic demyelination syndrome", "options": {"A": "Lateral medullary syndrome", "B": "Medial medullary syndrome", "C": "Osmotic demyelination syndrome", "D": "Hypercalcemia", "E": "Hypocalcemia"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 27-year-old woman presents to the emergency department with severe wheezing, which started an hour ago. She informs the doctor that she has had mild persistent asthma for the last 2 years and is on inhaled corticosteroids, and uses them regularly. She has not experienced asthma symptoms for the last 2 months and there is no history of non-compliance. She mentions that her present symptoms came on about 20 minutes after her last meal. When the doctor makes specific inquiries, she recollects items in her lunch, which included canned milk product, commercially available roasted peanuts, homemade celery salad, and wine. She also mentions that she took a tablet of acetaminophen immediately after the meal because her legs were aching since morning, which she attributes to her morning walk at 6 am the same day. She has never developed respiratory symptoms in response to milk protein, peanuts, or acetaminophen until now. Skin prick testing for food allergens, performed a month back, was negative for all the common food allergens, including milk and peanuts. Which of the following is the most likely trigger for her current episode?", "answer": "Food additive", "options": {"A": "Ara-h-1 protein", "B": "β-lactoglobulin", "C": "Food additive", "D": "Acetaminophen", "E": "Exercise"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 30-year old African-American woman comes into your office for pregnancy counseling with her husband. She states that both she and her husband have family histories of sickle cell disease. Based on previous genetic testing, they both also have a copy of the sickle cell gene from their parents, but neither of them has ever manifested symptoms associated with the disease. They want to conceive and are concerned about the chances that their child might have the disease. What is the chance the offspring will be a child WITHOUT sickle cell anemia?", "answer": "3/4", "options": {"A": "1/2", "B": "3/4", "C": "1/4", "D": "2/3", "E": "1/3"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 52-year-old man presents to the clinic complaining of blood in his urine. He had a mild respiratory illness 3 weeks ago. Urinalysis reveals a high red blood cell count and casts in the urine. A diagnosis of post-streptococcal glomerulonephritis is made. The physician explains that the treatment is supportive and that the patient needs to follow up with him every two weeks. Six weeks later, the patient returns to the clinic because he does not feel well; he has been experiencing malaise and fatigue. On examination, his pulse is 98/min, blood pressure is 135/85 mm Hg, temperature is 36.6°C (98.0°F), and respiratory rate is 16/min. He has a mildly distended abdomen. Blood tests reveal that the patient’s creatinine level has increased from 1.2 mg/dL to 3.0 mg/dL over the last month. He is referred to a nephrologist who diagnoses him with rapidly progressive glomerulonephritis (RPGN) and starts him on hemodialysis, as his potassium level has risen to 7 mEq/dL. The patient is advised to undergo renal transplantation. His human leukocyte antigen (HLA) genotype is A7/A5, B2/B9, C8/C3. The first allele in each locus is the maternal form; the second is paternal. Several potential donors are available for the renal graft. Which of the following would be the closest match?", "answer": "Donor A: tA7/A5, ttB8/B2, ttC3/C8", "options": {"A": "Donor B: tA5/A12, tB22/9, ttC4/C3", "B": "Donor A: tA7/A5, ttB8/B2, ttC3/C8", "C": "Donor E: tA7/A8, ttB9/B27, tC3/C4", "D": "Donor C: tA7/A4, ttB2/B4, ttC8/C3", "E": "Donor D: tA4/A7, ttB1/B8, ttC8/C3"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "An investigator is studying determinants of childhood obesity by observing a cohort of pregnant women with obesity. After delivery, he regularly records the height and weight of the cohort's children. The results of the correlation analysis between mean childhood BMI at 4 years of age and mean maternal BMI before pregnancy are shown. Based on these findings, which of the following is the most likely correlation coefficient?", "answer": "0.45", "options": {"A": "-0.45", "B": "1.80", "C": "0.45", "D": "0", "E": "-1.80"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 25-year-old woman comes to the physician for a routine examination. She is a recreational runner and for the past 3 months she has been training for a marathon. Yesterday she ran 17 km (10.5 mile). Menses occur at regular 28-day intervals and last 6 days. She drinks three to five beers when going out with friends. She follows a vegan diet. She appears well. Her temperature is 36.6°C (98.0°F), blood pressure is 110/72 mm Hg, pulse is 70/min, and respirations are 14/min. Physical examination shows no abnormalities. Laboratory studies show:\nHemoglobin 9.8 g/dL\nMean corpuscular volume 91 fL\nLactate dehydrogenase 400 U/L\nPlatelet count 250,000/mm3\nReticulocyte count 3%\nHaptoglobin 23 mg/dL (N=41–165 mg/dL)\nSerum\nIron 90 μg/dL\nFerritin 170 ng/mL\nTotal iron binding capacity (TIBC) 220 μg/dL (N=251–406 μg/dL)\nUrinalysis shows trace blood but no RBCs. Which of the following is the most likely cause of this patient's anemia?\"", "answer": "Intravascular hemolysis", "options": {"A": "Extravascular hemolysis", "B": "Vitamin B12 deficiency", "C": "Iron deficiency", "D": "Intravascular hemolysis", "E": "Impaired heme synthesis"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 45-year-old man comes into the ED after a car accident. After waiting an hour in the waiting room, he begins to berate the receptionist and demands to be seen by a doctor. During the exam, the patient brags that he recently had to quit his job because they did not appreciate his talent and drive. After a medical student declines his invitation for a date, he becomes very angry and throws supplies across the room. The physician manages the patient's physical injuries and begins to suspect the patient has a personality disorder. Which personality disorder is most likely?", "answer": "Narcissistic personality disorder", "options": {"A": "Borderline personality disorder", "B": "Narcissistic personality disorder", "C": "Avoidant personality disorder", "D": "Histrionic personality disorder", "E": "Obsessive-compulsive personality disorder"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 61-year-old man comes to the physician because of weight loss and a non-productive cough for 4 months. He has smoked 2 packs of cigarettes daily for 42 years. A CT scan of the chest shows an irregular mass at the right hilum and axillary lymphadenopathy. A biopsy of the mass obtained on bronchoscopy confirms the diagnosis of metastatic non-small cell lung cancer. Results of a molecular diagnostic test show a microdeletion on the short arm of chromosome 7. The physician recommends chemotherapy with erlotinib. The beneficial effect of this drug is most likely due to arrest in which of the following phases of the cell cycle?", "answer": "G1 phase", "options": {"A": "G2 phase", "B": "M phase", "C": "G1 phase", "D": "G0 phase", "E": "S phase"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 52-year-old woman comes to the physician because of a 4-day history of painful swallowing and retrosternal pain. She was diagnosed with HIV infection 2 months ago; her medications include tenofovir, emtricitabine, and raltegravir. Vital signs are within normal limits. Physical examination of the oral cavity shows no abnormalities. The patient's CD4+ T-lymphocyte count is 70/mm3 (N ≥ 500). Empiric treatment is started. Two weeks later, she reports no improvement in symptoms. Esophagogastroduodenoscopy is performed and shows multiple round superficial ulcers in the distal esophagus. Which of the following is the most likely underlying cause of this patient's symptoms?", "answer": "Infection with herpes simplex virus", "options": {"A": "Adverse effect of medication", "B": "Degeneration of ganglion cells within the myenteric plexuses", "C": "Eosinophilic esophageal infiltrate", "D": "Infection with herpes simplex virus", "E": "Infection with Candida species"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "An 18-year-old girl comes to the emergency room with abdominal pain. She states that the pain started 6 hours ago, is 8/10, and localizes to the right lower abdomen. She recalls a similar episode last month. Her older brother was hospitalized 2 years ago for perforated appendicitis. Her mother has diverticulitis. The patient got her first menstrual period at age 14. Her periods occur regularly every 28 days. Her last menstrual period was 2 weeks ago. She is sexually active with multiple partners and uses condoms inconsistently. The patient’s temperature is 99°F (37.2°C), blood pressure is 110/74 mmHg, pulse is 89/min, and respirations are 14/min with an oxygen saturation of 98% on room air. On physical exam, the patient is in moderate distress. There is lower abdominal tenderness with guarding. A pelvic examination reveals clear mucous in the vaginal introitus, a mobile uterus, and tenderness of the right adnexa. Labs are obtained, as shown below:\n\nLeukocyte count: 10,000/mm^3 with normal differential\nHemoglobin: 13.5 g/dL\nPlatelet count: 200,000/mm^3\nBeta-human chorionic gonadotropin: Pending\n\nA pelvic ultrasound demonstrates a small fluid collection in the cul-de-sac posterior to the uterus. Which of the following is the most likely diagnosis?", "answer": "Midcycle pain", "options": {"A": "Appendicitis", "B": "Endometriosis", "C": "Midcycle pain", "D": "Pelvic inflammatory disease", "E": "Ruptured ectopic pregnancy"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "In a suburban town in Virginia, epidemiologists are alarmed by the increasing number of squamous cell lung cancer cases. Further investigation reveals that most people in the area work in a glass factory, the region’s main source of employment. A researcher is interested in studying the role of immunosurveillance in the pathogenesis of this lung cancer. He postulates that tumor infiltration by natural killer (NK) cells has a better prognosis since they play a major role in immunosurveillance. NK cells also kill tumor cells by the perforin-mediated destruction of cancerous cells. The researcher is interested in studying tumor infiltration by NK cells in the resected specimen from patients within the cohort who have been diagnosed with stage 1 lung cancer. Which of the following cluster of differentiation markers will he need to use to identify these cells in the resected specimens?", "answer": "CD56", "options": {"A": "CD20", "B": "CD3", "C": "CD34", "D": "CD117", "E": "CD56"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 26-year-old man presents to the office complaining of persistent back pain for the past 3 months. You saw the patient previously and prescribed NSAIDs and rest, but he has not improved. The patient states that his maternal grandfather had ‘back problems his whole life’, and he worries that he might have the same issues. An X-ray is performed and shows squaring of the vertebrae with longitudinal fibrous bands. What is the most likely diagnosis?", "answer": "Ankylosing spondylitis", "options": {"A": "Scoliosis", "B": "Ehlers-Danlos syndrome", "C": "Osteosarcoma", "D": "Ankylosing spondylitis", "E": "Osteopetrosis"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A regional hospital system has decided to institute a new task group for quality improvement and patient safety. The task group would like to begin by decreasing the number of days given for narcotic pain medication prescriptions in the emergency department to at most 7 days instead of the hospital average of 21 days per prescription. Which of the following interventions would be most successful at achieving the task group’s mission?", "answer": "Changing the electronic medical record to only allow a maximum of 7 days per prescription", "options": {"A": "Educating patients about appropriate narcotics dosing", "B": "Printing out and posting handouts detailing the dangers of narcotics", "C": "Sending an email to all providers notifying them of narcotics prescribing best practices", "D": "Changing the electronic medical record to only allow a maximum of 7 days per prescription", "E": "Providing an alert in the electronic medical record that shows the ideal number of days per prescription"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 57-year-old man comes to the clinic complaining of nausea and 1 episode of vomiting during the past day. He denies any precipitating event except for a headache for which he took some acetaminophen yesterday. The headache is described as bilateral, dull, and 8/10 in severity. He has never had such symptoms before. His past medical history is significant for hypertension, biliary colic, and a past hospitalization for delirium tremens when he “tried to quit alcohol cold turkey.” When asked about his current alcohol intake, the patient looks away and mutters “just a couple of drinks here and there.” The patient reports mild abdominal pain that began this morning but denies vision changes, bowel changes, fever, or weight loss. Physical examination demonstrates tenderness at the right upper quadrant (RUQ) that does not worsens with inhalation. What is the most likely explanation for this patient’s symptoms?", "answer": "Accumulation of N-acetyl-p-benzoquinone imine in the liver", "options": {"A": "Accumulation of N-acetyl-p-benzoquinone imine in the liver", "B": "Impaction of a gallstone in the ileus", "C": "Malignant overgrowth of glial cells in the brain", "D": "Obstruction of the cystic duct by gallstone", "E": "Upregulation of alpha-2 adrenergic receptors"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 48-year-old patient comes to the physician because of a 4-day history fever, headaches, loss of appetite, and myalgia. Two weeks ago, the patient went on a camping trip to Wisconsin. His temperature is 39.5°C (103.1°F). Physical examination shows no rash or joint swelling. Laboratory studies show:\nHemoglobin 14.1 g/dL\nLeukocyte count 3,800/mm3\nPlatelet count 85,000/mm3\nSerum\nAST 48 U/L\nALT 52 U/L\nTreatment with doxycycline is begun and the patient recovers. A paired acute and convalescent indirect fluorescent antibody test confirms that the patient had anaplasmosis. The patient's condition was most likely transmitted by which of the following vectors?\"", "answer": "Ixodes tick", "options": {"A": "Louse", "B": "Lone star tick", "C": "Ixodes tick", "D": "Dog tick", "E": "Flea"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 42-year-old woman comes to the clinic complaining of upper abdominal pain. Her symptoms started 1 month ago with vague abdominal discomfort following a meal at a steakhouse. Since then the pain has progressed to the point that she has more than 5 episodes a week. The pain is worse with eating but has not affected her appetite. She also reports a burning sensation in her chest when she lies down at night after dinner. She denies weight loss or dysphagia. She takes no medications except daily calcium supplements. She drinks 2 glasses of wine per week and denies tobacco use. Her blood pressure is 110/78, pulse is 72/min, and respirations are 13/min. On physical examination, the patient’s abdomen is soft and non-distended. Normal bowel sounds are appreciation. There is mild epigastric tenderness but no guarding and no rebound. Fecal occult blood is negative. Which of the following is the next best step in management?", "answer": "Start omeprazole", "options": {"A": "Start antibiotic therapy", "B": "Start omeprazole", "C": "Stool antigen test for Helicobacter pylori", "D": "Surgical fundiplication", "E": "Upper gastrointestinal endoscopy"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 3-year-old boy presents to the pediatrician crying with ear pain and his temperature has been 101°F (38.3°C) for several days. His mother states that other children at his daycare center have been having similar symptoms. She further describes that he was fed formula and was not breastfed. The mother admits that she smokes cigarettes daily. On exam, the boy is irritable and crying, and frequently tugs on his left ear. Both tympanic membranes appear erythematous, and the left appears opaque and bulging with decreased mobility on pneumatic otoscopy. Which of the following is the best next step in management?", "answer": "Amoxicillin", "options": {"A": "Amoxicillin", "B": "Amoxicillin-clavulanic acid", "C": "TMP-SMX", "D": "Tympanocentesis", "E": "Supportive therapy"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 47-year-old G3P2 woman presents to her endocrinologist for a follow-up appointment. Her last menstrual period was at the age of 35 years. She now feels fatigued and cannot concentrate on her work or type properly on the keyboard because of an onset of tremor in her hands. Her symptoms are taking a toll on her quality of life. The patient’s blood pressure is 124/83 mm Hg, pulse is 91/min, respirations are 17/min, and temperature is 36.7°C (98.1°F). On physical examination, there is a mild enlargement of the thyroid; the gland is minimally firm in texture and is nontender. Which of the following pathologic findings is she most likely to have?", "answer": "Silent thyroiditis", "options": {"A": "Follicular thyroid neoplasia  ", "B": "Silent thyroiditis", "C": "Chronic lymphocytic thyroiditis", "D": "Granulomatous thyroiditis", "E": "Fibrous thyroiditis"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 44-year-old woman is brought to the emergency department after she was found lying in the park mumbling to herself. She is lethargic and disoriented. She has a 2-week history of increasing weakness, nausea, and vomiting. She denies any recent alcohol or drug use. She has a history of systemic lupus erythematosus but stopped taking methotrexate many years ago. Her temperature is 37.3°C (99.1°F), pulse is 89/min, and blood pressure is 154/91 mm Hg. On mental status examination, she is confused and only oriented to person, but not to place or time. She is unable to name the days of the week backwards. She exhibits moderate generalized weakness. Physical exam shows jugular venous distention and pitting edema in the lower extremities. Laboratory studies show:\nSerum\nNa+ 137 mEq/L\nK+ 5.5 mEq/L\nCl- 120 mEq/L\nBicarbonate 15 mEq/L\nUrea nitrogen 94 mg/dL\nCreatinine 5.5 mg/dL\nGlucose 92 mg/dL\nWhich of the following is the most appropriate next step in management?\"", "answer": "Hemodialysis", "options": {"A": "Administer lactulose", "B": "Hemodialysis", "C": "Restart methotrexate", "D": "Begin low-protein diet", "E": "Fluid restriction"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "An investigator is studying the secretion of gastrointestinal hormones before and after food intake. She isolates a hormone that accelerates the emptying of gastric contents into the duodenal bulb. The isolated hormone is most likely which of the following?", "answer": "Gastrin", "options": {"A": "Glucagon-like peptide", "B": "Gastrin", "C": "Cholecystokinin", "D": "Vasoactive intestinal peptide", "E": "Secretin"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 45-year-old woman presents to the office with a chief complaint of a cough that has persisted for a month and a half. She also has night fevers and has lost 5 kg (11 lb) in the last 2 months. She recently returned from a 6-month trip to Peru. Her vitals include: heart rate 82/min, respiratory rate 17/min, temperature 38.0°C (100.4°F), and blood pressure 107/80 mm Hg. On auscultation, she has diminished respiratory sounds at the base of the right lung. Chest radiography shows an opacity in the right apex. What is the most likely cause of her presentation?", "answer": "Tuberculosis", "options": {"A": "Echinococcosis", "B": "Tuberculosis", "C": "Pulmonary thromboembolism", "D": "Heart failure", "E": "Lung cancer"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 52-year-old homeless man is brought to the urgent care clinic with altered mental status and disorientation for the last day. Past medical records are unavailable. His temperature is 37°C (98.6°F), the respiratory rate is 15/min, the pulse is 107/min, and the blood pressure is 92/67 mm Hg. He has a flapping tremor of the wrists during attempted extension. He is started on intravenous D5 1/2NS and blood is drawn for further testing. His condition deteriorates overnight. On re-examination the next morning, he has developed visual disturbances with a new horizontal nystagmus and a staggering gait. His blood tests show: \nSerum\nAlbumin 3.2 gm/dL\nAlkaline phosphatase 150 U/L\nAlanine aminotransferase 76 U/L\nAspartate aminotransferase 155 U/L\nGamma-glutamyl transpeptidase 202 U/L\nWhat is the most likely diagnosis?", "answer": "Wernicke's encephalopathy", "options": {"A": "Alcohol-related dementia", "B": "Hepatic encephalopathy", "C": "Acute liver failure", "D": "Delirium", "E": "Wernicke's encephalopathy"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 27-year-old woman comes to the emergency department at 14 weeks gestation with abdominal pain. She states she has passed a large amount of blood from her vagina in the past 2 hours. Her vitals are within normal limits and she describes her abdominal pain as a 4/10. Physical exam is notable for a dilated cervix. The patient states she does not want any invasive procedures in her workup but is accepting to necessary medical interventions. Which of the following is the best next step in management?", "answer": "Expectant management", "options": {"A": "Admission and external fetal monitoring", "B": "Dilation and curettage", "C": "Expectant management", "D": "Misoprostol", "E": "Transvaginal ultrasound"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 25-year-old female is admitted to the hospital for an intrauterine fetal demise (IUFD) during her 30th gestational week. The patient did not receive any prenatal care or screenings. The baby is delivered via C-section and the family wishes to conduct an autopsy to understand the reason for the IUFD and to better prepare for future pregnancies. On autopsy, the fetus is discovered to have severe facial abnormalities as well as a brain lacking the normal sagittal fissure. Which of the following genes was most likely mutated in this fetus?", "answer": "Sonic hedgehog", "options": {"A": "Hox", "B": "FGF", "C": "Wnt-7", "D": "Sonic hedgehog", "E": "BMP"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A healthy 32-year-old woman enrolls in a study investigating kidney function. Her renal plasma flow (RPF) is 600 mL/min. She is administered an intravenous substance that does not undergo tubular reabsorption. The following sets of measurements are taken every 10 minutes:\nPlasma concentration of substance Excretion rate of substance\nSet 1 0.1 mg/mL 60 mg/min\nSet 2 0.15 mg/mL 90 mg/min\nSet 3 0.2 mg/mL 104 mg/min\nSet 4 0.25 mg/mL 110 mg/min\nSet 5 0.3 mg/mL 116 mg/min\nThis patient was most likely administered which of the following substances?\"", "answer": "Para-aminohippurate", "options": {"A": "Cystatin C", "B": "Glucose", "C": "Para-aminohippurate", "D": "Inulin", "E": "Iohexol"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 6-year-old girl is brought to the physician for a well-child examination. She has no history of serious illness. Her temperature is 37°C (98.6°F), pulse is 95/min, and blood pressure is 96/52 mm Hg. Examination shows a 2/6 continuous, low-pitched murmur over the left upper sternal border that radiates towards the neck. The murmur disappears when she flexes her neck. The remainder of the examination shows no abnormalities. Which of the following is the most likely diagnosis?", "answer": "Venous hum", "options": {"A": "Patent ductus arteriosus", "B": "Venous hum", "C": "Coronary artery fistula", "D": "Aortic stenosis", "E": "Mitral valve prolapse"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 72-year-old man with a history of hypertension and hyperlipidemia presents to the emergency department with three-days of fever, cough, and shortness of breath. On physical exam, temperature is 101.3 deg F (38.5 deg C), pulse is 106/min, blood pressure is 148/92 mmHg, and respiratory rate is 24/min. Crackles are auscultated on the right lower lobe. Chest radiograph demonstrates right lower lobe opacities concerning for consolidation. Sodium level is 118 mEq/L. He is admitted to the hospital on empiric antibiotics. What is the most appropriate management of this patient’s hyponatremia?", "answer": "Fluid restriction", "options": {"A": "Hypertonic saline", "B": "Normal saline", "C": "Fluid restriction", "D": "Salt tablets", "E": "Demeclocycline"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 75-year-old man presents to the physician for a follow-up examination. Over the last several months, he reports dyspnea when walking during his daily exercise routine. He feels tired most of the time. He has no fever or weight loss. He has no history of severe illness and takes no medications. He does not smoke, drinks alcohol, or follow a particular diet. The vital signs are within normal limits. The physical examination reveals pale conjunctiva. The examination of the heart, lungs, abdomen, and extremities shows no abnormalities. No lymphadenopathy is palpated. The laboratory studies show the following:\nHemoglobin 8.5 g/dL\nMean corpuscular volume 105 μm3\nLeukocyte count 4,500/mm3\nPlatelet 160,000/mm3\nAbdominal ultrasonography shows no organomegaly or other pathologic findings. The peripheral blood smear shows large and hypogranular platelets and neutrophils with hypo-segmented or ringed nuclei. No blasts are seen. Bone marrow aspiration shows hypercellularity. In addition, ring sideroblasts, hypogranulation, and hyposegmentation of granulocyte precursors, and megakaryocytes with disorganized nuclei are present. Marrow myeloblasts are 4% in volume. Which of the following best explains these findings?", "answer": "Myelodysplastic syndrome", "options": {"A": "Acute myeloid leukemia", "B": "Aplastic anemia", "C": "Myelodysplastic syndrome", "D": "Primary myelofibrosis", "E": "Vitamin B12 deficiency"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 37-year-old man comes to the physician because of a 1-month history of a burning sensation in his chest. The sensation is most prominent when he is lying in bed, but it is also present after eating heavy meals. He also states his breath has an unpleasant odor in the morning. He has not lost any weight during this period. He has hypothyroidism. His father died of colon cancer and his mother has hypertension. He has smoked one pack of cigarettes daily for 15 years and drinks 2–3 beers on weekends. His medications include levothyroxine and an over-the-counter multivitamin. He is 170 cm (5 ft 7 in) tall and weighs 95 kg (210 lb); BMI is 32.9 kg/m2. Vital signs are within normal limits. Physical examination shows no abnormalities. Which of the following is the next best step in management?", "answer": "Proton-pump inhibitor", "options": {"A": "Urea breath test", "B": "Proton-pump inhibitor", "C": "H2 receptor blocker", "D": "Barium swallow", "E": "Calcium carbonate\n\""}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 36-year-old man presents with right upper quadrant pain, fatigue, and pruritus. His past medical history is significant for ulcerative colitis diagnosed 5 years ago, which is well-managed medically. He is vaccinated against hepatitis A and B and denies any recent travel abroad. On physical examination, mild jaundice of the skin is present. An abdominal examination reveals significant hepatosplenomegaly. A percutaneous liver biopsy is performed. Which of the following histopathologic findings would most likely be seen on the liver biopsy of this patient?", "answer": "Onion skin fibrosis (concentric periductal fibrosis)", "options": {"A": "Small drops of fat throughout the liver parenchyma", "B": "Normal histologic findings", "C": "Mononuclear cell infiltrate and apoptotic hepatocytes", "D": "Damage to the basement membrane of the biliary ducts and reactive hyperplasia of the epithelial duct lining", "E": "Onion skin fibrosis (concentric periductal fibrosis)"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 26-year-old man is brought to the emergency department because he has had abdominal pain, nausea, and vomiting for the past 2 hours. He ate a sandwich and coleslaw from a deli about 1 hour before the symptoms began. He has no history of serious illness and takes no medications. His temperature is 99.6°F (37.6°C), pulse is 80/min, respirations are 18/min, and blood pressure is 122/68 mm Hg. The lungs are clear to auscultation. Cardiac examination shows no abnormalities. Abdominal examination shows diffuse mild tenderness with no rigidity, rebound, or guarding. The remainder of the examination shows no abnormalities. Which of the following is the most likely causal organism?", "answer": "Staphylococcus aureus", "options": {"A": "Shigella dysenteriae", "B": "Yersinia enterocolitica", "C": "Staphylococcus aureus", "D": "Enterotoxigenic Escherichia coli", "E": "Bacillus cereus"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 12-year-old girl is brought to the emergency department because of severe pain and swelling of her right eye for 3 days. Over the past two weeks, she had nasal congestion and a constant, mild headache. She did not visit a doctor and instead took over-the-counter naproxen and phenylephrine. Her nasal congestion has since improved, but the headache persists. She underwent a dental procedure for caries about ten days ago. She does not recollect any recent insect bites or trauma. Her immunizations are up-to-date. She appears ill and reports occasional chills. Her temperature is 38.3°C (101°F), pulse is 89/min, and blood pressure is 110/70 mm Hg. Examination shows proptosis of the right eye. Vision is impaired in the affected eye. Her right upper and lower eyelid are erythematous, swollen, and tender to touch. Ocular movements cause severe pain. Her headache is worsened by leaning forward and improves when the patient is lying on her back. Which of the following is the most likely cause of the patient's symptoms?", "answer": "Bacterial infection from ethmoidal sinus", "options": {"A": "Cavernous sinus thrombosis", "B": "Dental abscess", "C": "Suppurative spread of dacrocystitis", "D": "Bacterial infection from sphenoid sinus", "E": "Bacterial infection from ethmoidal sinus"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 45-year-old man presents to the emergency room with fever and headache. He recently had a middle ear infection. On physical examination, when the head is passively flexed towards the chest, then flexion of the knee is observed. In addition, he reports that his headache increases after rotating his head horizontally. Lumbar puncture and CSF analysis were done. Which of the following laboratory findings would best represent your suspected diagnosis?", "answer": "Glucose: ↓, Proteins: ↑, Cells: 90% neutrophils, Lactic Acid (mmol/l): 4.5", "options": {"A": "Glucose: ↑, Proteins: ↑, Cells: 10% lymphocytes, Lactic Acid (mmol/l): 3.0", "B": "Glucose: ↓, Proteins: normal, Cells: 10% lymphocytes, Lactic Acid (mmol/l): 2.8", "C": "Glucose: ↑, Proteins: ↓, Cells: 90% neutrophils , Lactic Acid (mmol/l): 4.3", "D": "Glucose: normal, Proteins: normal, Cells: 90% neutrophils , Lactic Acid (mmol/l): 3.3", "E": "Glucose: ↓, Proteins: ↑, Cells: 90% neutrophils, Lactic Acid (mmol/l): 4.5"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 6-day-old female infant is brought to the emergency department because of poor feeding and irritability for two days. She was born at 39 weeks' gestation, and the pregnancy and delivery were uncomplicated. Her temperature is 39.2°C (102.6°F). She appears lethargic and makes occasional twitching movements in both upper extremities. The anterior fontanelle is soft and full. A lumbar puncture is performed and analysis of the cerebrospinal fluid shows increased protein and decreased glucose. Cerebrospinal fluid culture shows gram-positive, intracellular rods with tumbling motility. Infection of a healthy adult with the pathogen affecting this infant would most likely present with which of the following clinical conditions?", "answer": "Gastroenteritis", "options": {"A": "Cystitis", "B": "Pneumonia", "C": "Pelvic inflammatory disease", "D": "Meningitis", "E": "Gastroenteritis"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 64-year-old man has complaints of scrotal pain and swelling for the past 2 weeks. The pain is so severe that he is now unable to even sit comfortably for more than 5 minutes. Additionally, he complains of an inability to hold urine when he has an urge to urinate and of mild discomfort during urination. His medical history is significant for hypertension that is well-controlled with losartan. He smokes 1 pack of cigarettes every day and has been doing so for the past 25 years. On physical examination, swelling and erythema of the right hemiscrotal sac are evident, accompanied by intense tenderness with palpation of an indurated epididymis. What is the most likely infectious agent responsible for this patient’s condition?", "answer": "Escherichia coli", "options": {"A": "Chlamydia trachomatis", "B": "Neisseria gonorrhoeae", "C": "Coxsackievirus", "D": "Mumps virus", "E": "Escherichia coli"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 65-year-old female is diagnosed with invasive ductal carcinoma of the breast. After a lumpectomy with a negative axillary lymph node dissection and subsequent radiation therapy, the patient is started on adjuvant chemotherapy with anastrozole. Which of the following is an expected side effect of this medication?", "answer": "Increased risk for osteoporosis", "options": {"A": "Increased risk for endometrial carcinoma", "B": "Decreased LDL and increased HDL levels", "C": "Mental confusion progressing to more severe dementia", "D": "Increased risk for osteoporosis", "E": "Excessive weight loss"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "An 18-year-old man comes to the physician because of fatigue, back pain, and dark-colored urine for two days. He has no history of serious illness. He recently sprained his ankle playing basketball and has been taking ibuprofen as needed for pain. Physical examination shows scleral icterus. Laboratory studies show a hemoglobin concentration of 9.2 g/dL and serum lactate dehydrogenase concentration of 254 U/L. A photomicrograph of a peripheral blood smear with Wright's stain is shown. Which of the following is the most likely mode of inheritance for this patient's condition?", "answer": "X-linked recessive\n\"", "options": {"A": "Autosomal recessive", "B": "X-linked dominant", "C": "Autosomal dominant", "D": "Mitochondrial inheritance", "E": "X-linked recessive\n\""}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 32-day-old boy is brought to the pediatrician with complaints of purulent discharge from the umbilicus and perianal ulceration for the past few days. A detailed developmental history reveals that he was born to a couple who had a non-consanguineous marriage. He was born by normal delivery at 39 weeks of gestation and his neonatal period was uneventful. His birth weight was 2.9 kg (6.3 lb) and he is exclusively breastfed. His parents also report that he has had 25–30 episodes of loose stools per day since his seventh day of life. His umbilical cord fell off on the 25th day of life. His temperature is 38.6ºC (101.4°F), pulse is 110/min, and respiratory rate is 35/min. On physical examination, erythema and induration are noted around the umbilicus and mild hepatosplenomegaly is present. His laboratory studies show:\nHemoglobin 12.9 gm/dL\nLeukocyte count 73,000/mm3\nPlatelet count 170,000/mm3\nPeripheral smear Hypersegmented polymorphs, toxic granules\nStool pH 6\nWhich of the following tests is most likely to yield an accurate diagnosis?", "answer": "Flow cytometry", "options": {"A": "Ultrasonography of the abdomen and pelvis", "B": "Flow cytometry", "C": "Magnetic resonance imaging", "D": "Complete blood count", "E": "Urine culture and sensitivity"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 1-hour-old newborn male is evaluated in the delivery room. The infant was born at 37 weeks gestation to a 39-year-old G3. The mother initially labored at home with a midwife but was transferred to the hospital for failure to progress. The infant was eventually delivered via Caesarean section. The mother declined all prenatal screening during this pregnancy. Upon delivery, the infant is found to have a 3 cm full-thickness defect in the abdominal wall to the right of the umbilicus with evisceration of a loop of bowel. His Apgar scores were 7 and 8 at 1 and 5 minutes, respectively. His weight is 3.0 kg (6.6 lb), and his height and head circumference are in the 30th and 40th percentiles, respectively. The abdominal defect is immediately covered in sterile saline dressings, and an orogastric tube and two peripheral intravenous lines are placed.\n\nThis condition is associated with which of the following additional cardiac defects?", "answer": "No cardiac defects", "options": {"A": "No cardiac defects", "B": "Bicuspid aortic valve", "C": "Endocardial cushion defect", "D": "Tetralogy of Fallot", "E": "Ventricular septal defect"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 17-year-old girl is brought to the physician for a well-child examination. She is worried about gaining weight. She frequents buffet restaurants but feels guilty soon after. She has a history of burning her extremities with cigarettes. Her last menstrual period was 3 weeks ago. She attends high school and plays field hockey on the school team. She is at the 25th percentile for height, 12th percentile for weight, and 17th percentile for BMI. Examination shows bilateral parotid gland enlargement. Oropharyngeal examination shows perimolysis. The remainder of the examination shows no abnormalities. Which of the following is the most likely diagnosis?", "answer": "Bulimia nervosa", "options": {"A": "Major depressive disorder", "B": "Bulimia nervosa", "C": "Obsessive compulsive disorder", "D": "Body dysmorphic disorder", "E": "Anorexia nervosa\n\""}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 37-year-old man with a history of depression has a two-year history of slowly worsening movement abnormalities characterized by rapid, involuntary, nonrepetitive movements involving his face, trunk, and limbs presents to clinic. He has also noted worsening of his depression, along with symptoms of increased anxiety and irritability. During the interview, his wife explains that he has suffered cognitive decline, most notably in the realm of executive function. On family history, you discover that his father suffered from a similar illness before dying at the age of 44. What would be the expected findings on brain MRI?", "answer": "Atrophy of the caudate nucleus", "options": {"A": "Normal brain MRI", "B": "Atrophy of the caudate nucleus", "C": "Periventricular high-signal intensity lesions on FLAIR sequence", "D": "Atrophy of the hippocampi", "E": "A ring-enhancing lesions after administration of radiocontrast"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 55-year-old man with a history of diabetes and hypertension presents to the emergency department when he found half of his face paralyzed this morning. The patient was last seen normal the night before by his wife and woke up with these symptoms. He has a past medical history of diabetes and hypertension and is not currently taking any medications for these conditions. His temperature is 98.5°F (36.9°C), blood pressure is 177/118 mmHg, pulse is 90/min, respirations are 15/min, and oxygen saturation is 99% on room air. Physical exam is notable for an inability for the patient to move any part of his face on the right side. The rest of his neurological exam is within normal limits. Which of the following is the next best step in management for the most likely diagnosis?", "answer": "Topical lubricants and discharge", "options": {"A": "CT scan of the head", "B": "Elevation of the head of the bed and intubation", "C": "MRI of the head", "D": "Tissue plasminogen activator", "E": "Topical lubricants and discharge"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A newborn boy develops excessive bilious vomiting 4 hours after delivery. The infant was born vaginally to a 29-year-old mother (gravida 2, para 1) at 38 weeks gestation. History was significant for polyhydramnios detected at 32 weeks and monitored for the duration of gestation. He was put to the breast right after birth and sucked actively. He still has not passed meconium. The patient’s vital signs include: blood pressure 77/50 mm Hg, heart rate 128/min, respiratory rate 37/min, and temperature 36.4℃ (97.5℉). On physical examination, the newborn appears fussy and mildly dehydrated. His abdomen appears rounded, soft and nontender on palpation, with no palpable organomegaly or masses. What is the most probable site of obstruction?\n   ", "answer": "Duodenum, distal to Vater’s papilla", "options": {"A": "Duodenum, proximal to Vater’s papilla", "B": "Esophagus", "C": "Gastric pylorus", "D": "Duodenum, distal to Vater’s papilla", "E": "Sigmoid colon"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "The patient is counselled about her risk of thyroid malignancy. Serum studies show:\nNa+ 138 mEq/L\nK+ 4.1 mEq/L\nCl- 101 mEq/L\nTSH 0.03 μU/mL\nCalcium 9 mg/dL\nWhich of the following is the most appropriate next step in management?\"", "answer": "Thyroid scintigraphy scan", "options": {"A": "Close monitoring", "B": "Free T4 and T3 levels", "C": "Fine-needle aspiration biopsy", "D": "Open biopsy", "E": "Thyroid scintigraphy scan"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "An 18-month-old girl is brought to her pediatrician because of swelling in her hands and feet. Her mother is concerned because she has been inconsolable for the last 8 hours. The mother adds that the girl has been getting tired easily recently. The vital signs include: temperature 38.0°C (100.4°F), blood pressure 90/55 mm Hg, and pulse 122/min. Gentle palpation of the metacarpal and metatarsal bones causes the infant to scream. The laboratory evaluation is remarkable for mild anemia, leukocytosis, and increased reticulocyte count. Her peripheral blood smear is shown in the picture. Which of the following best represents the etiology of this infant condition?", "answer": "Abnormal globin chain structure", "options": {"A": "Red cell enzymatic deficiency", "B": "Red cell membrane protein defect", "C": "Abnormal heme synthesis", "D": "Abnormal globin chain structure", "E": "Abnormal globin chain synthesis"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 34-year-old gravida-1 at 8 weeks gestation seeks evaluation for a fever and sore throat for 3 days. She also reports generalized body pain and fatigue over this period. She was diagnosed with Graves’ disease 6 months ago. Before conception, methimazole was switched to propylthiouracil. She appears ill. The vital signs include: axillary temperature 38.0℃ (100.4℉), pulse 88/min, respiratory rate 12/min, and blood pressure 120/80 mm Hg. A 1 × 1 cm ulcer is seen on the side of the tongue. The ulcer is tender with surrounding erythema. Examination of the neck, lungs, heart, and abdomen shows no abnormalities. The laboratory studies show the following:\nHemoglobin 13.5 g/dL\nMean corpuscular volume 90 μm3\nLeukocyte count 2,500/mm3\nSegmented neutrophils 5%\nLymphocytes 88%\nPlatelet count 240,000/mm3\nAlanine aminotransferase 18 U/L\nAspartate transaminase 16 U/L\nWhich of the following is the most appropriate next step in management?", "answer": "Discontinuation of propylthiouracil", "options": {"A": "Acetaminophen for fever control", "B": "Discontinuation of propylthiouracil", "C": "Oral ampicillin", "D": "Rectal temperature measurement", "E": "Termination of pregnancy"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 27-year-old man comes to the physician because of a 1-week history of fever and pain with urination. His temperature is 39°C (102.2°F). Physical examination shows no abnormalities. A photomicrograph of a urine sample is shown. This patient's findings indicate damage to which of the following structures?", "answer": "Renal interstitium", "options": {"A": "Urethra", "B": "Ureter", "C": "Renal interstitium", "D": "Glomerulus", "E": "Urinary bladder"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "Twelve hours after undergoing uncomplicated total knee replacement, a 55-year-old man develops increasing anxiety, agitation, hand tremor, and nausea. He told the nurse he saw a bear in his room. His pain has been controlled with intravenous morphine. He has a history of advanced liver disease. He drinks 7 cans of beer daily. He is diaphoretic. His temperature is 37.6°C (99.7°F), pulse is 118/min, respirations are 18/min, and blood pressure is 146/92 mm Hg. Administration of which of the following drugs is the most appropriate next step in management?", "answer": "Lorazepam", "options": {"A": "Chlordiazepoxide", "B": "Cyproheptadine", "C": "Lorazepam", "D": "Dantrolene", "E": "Carbamazepine"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 45-year-old woman comes to the physician’s office with complaints of jaw pain. When she eats, yawns, or rubs her jaw, she gets intense, shooting pains down the left side of her jaw, including her lower lip and chin. These episodes last about 30 seconds and have recurred about 10 times per day for the last month. She finds these episodes extremely distressing and comes to the physician’s office in hope of finding a treatment. The patient denies any locking of her jaw. Physical exam is not notable for any tenderness to palpation over the jaw. She has no crepitus in her temporomandibular joint. The patient is able to open and close her jaw without pain. The nerve involved in this patient’s clinical presentation exits the skull through which of the following brain structures?", "answer": "Foramen ovale", "options": {"A": "Superior orbital fissure", "B": "Foramen rotundum", "C": "Foramen ovale", "D": "Foramen spinosum", "E": "Jugular foramen"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 64-year-old woman presents to the hospital for chemotherapy. She has newly diagnosed acute myeloid leukemia. She is due to receive treatment with bendamustine for 2 days. On day 2 of her treatment, the patient complains of intense pain in her right great toe. On physical exam, the metatarsophalangeal joint of the 1st toe is warm, erythematous, swollen, and tender to both movement and palpation. An arthrocentesis is performed that reveals negatively birefringent needle-shaped crystals under polarized light. A Gram stain of the synovial fluid is negative. In addition to adequate intravenous hydration, which of the following if given would have most likely prevented the patient’s symptoms?", "answer": "Allopurinol", "options": {"A": "Acetazolamide", "B": "Allopurinol", "C": "Colchicine", "D": "Corticosteroids", "E": "Probenecid"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 29-year-old woman comes to the physician with complaints of fever, headache, and rash, which have gradually worsened over the past 6 days. The patient informs the physician that the rash appeared after 2 days of fever. The rash started at the wrists and ankles and then gradually spread to the trunk, palms, and soles. On examination, the physician notes a maculopapular rash as shown in the image below. Vital signs show a temperature of 39.4°C (103.0°F), a blood pressure of 110/70 mm Hg, and a pulse rate of 86/min. Which of the following is the most likely diagnosis?", "answer": "Rocky Mountain spotted fever", "options": {"A": "Ehrlichiosis", "B": "Endemic typhus", "C": "Lyme disease", "D": "Rocky Mountain spotted fever", "E": "Q fever"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 25-year-old man presents to the emergency department after paramedics picked him up from an electronic music festival. His temperature is 103°F (39.4°C), blood pressure is 167/105 mmHg, and pulse is 122/min. On physical exam, the patient is highly alert, agitated, and diaphoretic. Laboratory testing is significant for a serum sodium concentration of 130 mEq/L. Which of the following was most likely ingested by the patient?", "answer": "3,4-methylenedioxymethamphetamine", "options": {"A": "Heroin", "B": "Ketamine", "C": "Phencyclidine", "D": "3,4-methylenedioxymethamphetamine", "E": "Lysergic acid diethylamide"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 1-day-old male is seen in the neonatal intensive care unit for respiratory distress. He was born at 37 weeks to a 24-year-old G3P11011 Rh- mother who had no prenatal care. On physical examination, temperature is 99°F (37.2°C), blood pressure is 120/85 mmHg, pulse is 120/min, respirations are 26/min, and pulse oximetry is 92% on room air. There is abdominal distention with a positive fluid wave. Laboratory results are as follows:\n\nSerum:\nAlkaline phosphatase: 80 U/L\nALT: 33 U/L\nAST: 32 U/L\nBilirubin (total): 10 mg/dL\nBilirubin (conjugated): 0.2 mg/dL\nAmylase: 76 U/L\n\nLeukocyte count: 5,000/mm^3 with normal differential\nHemoglobin: 8 g/dL\nPlatelet count: 200,000/mm^3\nMean corpuscular volume: 80 µm^3\nReticulocyte count: 3%\n\nWhat is the most likely diagnosis?", "answer": "Erythroblastosis fetalis", "options": {"A": "Dubin-Johnson syndrome", "B": "Gilbert syndrome", "C": "Breast feeding jaundice", "D": "Beta-thalassemia minor", "E": "Erythroblastosis fetalis"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "Study X examined the relationship between coffee consumption and lung cancer. The authors of Study X retrospectively reviewed patients' reported coffee consumption and found that drinking greater than 6 cups of coffee per day was associated with an increased risk of developing lung cancer. The same study in lab mice; however, did not come to a similar conclusion. Which of the following most likely explains the difference between these 2 studies?", "answer": "Confounding", "options": {"A": "Confounding", "B": "Lead time bias", "C": "Measurement bias", "D": "Observer bias", "E": "Selection bias"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 2-day-old boy was born at 38 weeks gestation to a 37-year-old woman by vaginal delivery. Since birth, the boy has had difficulty latching onto the breast but has not vomited or passed meconium. Examination reveals a flat facial profile with epicanthal eyelids, low-set earlobes, and a transverse crease on each palm. The abdomen is distended with absent breath sounds in the hypogastric region. A digital rectal examination shows a patent anal canal and is followed by a projected expulsion of gas and stool. What is the most likely mechanism underlying this patient’s findings?", "answer": "Failure of neural crest cell migration during embryologic development", "options": {"A": "Hypertrophic pylorus causing retrograde flow of gastric contents", "B": "Inspissated meconium causing intestinal obstruction", "C": "Failure of neural crest cell migration during embryologic development", "D": "Atresia of the duodenum", "E": "Telescoping of 2 parts of the intestine into each other"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "An otherwise healthy 23-year-old newly-married woman comes to the physician because of a 6-day history of discomfort in her vaginal area during and after sexual intercourse. Her last menstrual period was 3 weeks ago. Two years ago, she was diagnosed with genital herpes which was treated with acyclovir. She has been in a monogamous relationship for the past year and has been using an intrauterine device for contraception for the past month. Examination shows a 4-cm, mildly tender mass in the inferior aspect of the left labium minus with no signs of inflammation. Speculum examination causes her discomfort but shows no abnormalities. Which of the following is the most likely cause of these findings?", "answer": "Obstructed orifice of the Bartholin duct", "options": {"A": "Obstructed orifice of the Bartholin duct", "B": "Obstructed orifice of a sebaceous gland", "C": "Reactivation of the genital herpes", "D": "Squamous cell carcinoma of the vulva", "E": "Allergic reaction to the intrauterine device"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 22-year-old professional softball player is undergoing an annual check-up. Her medical history is significant for hallux valgus and scoliosis. She additionally notes that she frequently has bumps and bruises from playing softball, but she has no injuries today. Her family history is significant for heart disease. The patient's blood pressure is 110/70 mm Hg, heart rate is 78/min, and respiratory rate is 15/min. A physical examination is unremarkable except for an indurated palpable mass on her left breast. A biopsy of the mass is performed. Which biopsy findings are most likely to be present in this patient?", "answer": "Necrotic fat with calcifications and giant cells", "options": {"A": "Chronic inflammation with plasma cells", "B": "Necrotic fat with calcifications and giant cells", "C": "Leaf-like projections", "D": "Duct-like structures", "E": "Abundant extracellular mucin"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 5-month-old male infant is brought to the physician by his parents for the evaluation of a progressive enlargement of his head circumference. His parents report that he has been healthy except for an episode of tonsillitis 3 months ago treated with penicillin. The patient was born at term by a lower segment transverse cesarean section because of a transverse lie. He has met all developmental milestones. His immunizations are up-to-date. The patient is at the 50th percentile for length, 50th percentile for weight, and 95th percentile for head circumference. He appears well-nourished. His temperature is 37°C (98.6°F), pulse is 120/min, and blood pressure is 90/60 mm Hg. Physical examination shows a tense anterior fontanelle. The eyes deviate inferiorly and the eyelids are retracted. Which of the following is the most appropriate next step in the management of this patient?", "answer": "Ultrasound of the head", "options": {"A": "Administer furosemide", "B": "Serial lumbar punctures", "C": "CT scan of the head", "D": "Place a CSF shunt", "E": "Ultrasound of the head"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 37-year-old G1P1001 delivers a male infant at 9 pounds 6 ounces after a C-section for preeclampsia with severe features. The mother has a history of type II diabetes with a hemoglobin A1c of 12.8% at her first obstetric visit. Before this pregnancy, she was taking metformin, and during this pregnancy, she was started on insulin. At her routine visits, her glucose logs frequently showed fasting fingerstick glucoses above 120 mg/dL and postprandial values above 180 mg/dL. In addition, her routine third trimester culture for group B Streptococcus was positive. At 38 weeks and 4 days gestation, she was found to have a blood pressure of 176/103 mmHg and reported a severe headache during a routine obstetric visit. She denied rupture of membranes or vaginal bleeding. Her physician sent her to the obstetric triage unit, and after failure of several intravenous doses of labetalol to lower her blood pressure and relieve her headache, a C-section was performed without complication. Fetal heart rate tracing had been reassuring throughout her admission. Apgar scores at 1 and 5 minutes were 7 and 10. After one hour, the infant is found to be jittery; the infant's temperature is 96.1°F (35.6°C), blood pressure is 80/50 mmHg, pulse is 110/min, and respirations are 60/min. When the first feeding is attempted, he does not latch and begins to shake his arms and legs. After 20 seconds, the episode ends and the infant becomes lethargic. Which of the following is the most likely cause of this infant’s presentation?", "answer": "ß-cell hyperplasia", "options": {"A": "Transplacental action of maternal insulin", "B": "ß-cell hyperplasia", "C": "Neonatal sepsis", "D": "Inborn error of metabolism", "E": "Neonatal encephalopathy"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 65-year-old male presents to his cardiologist to discuss increasing episodes of dyspnea after climbing stairs. He also now needs three pillows at night to sleep. Physical examination reveals an early diastolic murmur best appreciated at the left sternal border with bounding peripheral pulses. The cardiologist is very concerned and immediately refers the patient for a surgical workup. What is the most likely diagnosis?", "answer": "Aortic regurgitation", "options": {"A": "Mitral valve insufficiency", "B": "Aortic regurgitation", "C": "Mitral stenosis", "D": "Aortic stenosis", "E": "Atrial myxoma"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 42-year-old overweight restaurant waiter develops excruciating pain in the heel of his right foot. Symptoms are most intense after getting out of bed but get better after walking. On physical examination, both feet have a flat medial arch. There is tenderness to palpation along the inner aspect of the right heel bone, minimal active dorsiflexion, and pain at passive dorsiflexion. X-ray films reveal a bone spur at the level of the attachment of the right plantar fascia. The spur is also present in the comparison film of the left foot. He is diagnosed with plantar fasciitis and is told to lose weight, rest, use ice, and take anti-inflammatory medications. Which of the following is most accurate?", "answer": "This was caused by excessive strain on the medial fascicle.", "options": {"A": "The central fascicle is the thinnest and the most likely to rupture.", "B": "The underlying structures of the sole of the foot are intact.", "C": "The patient's windlass mechanism remains intact.", "D": "This was caused by excessive strain on the medial fascicle.", "E": "The pain in the right foot is caused by the bone spur."}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 7-year-old boy is brought to the physician because of decreased vision, hearing, and speaking over the past 3 months. During this time, he has also had difficulty walking, concentrating, drawing, and feeding himself. His maternal male cousin had similar complaints and died at the age of 5 years. Examination shows hyperpigmented skin and nails. His speech is dysarthric. Neurologic examination shows an ataxic gait, spasticity, and decreased muscle strength in all extremities. Fundoscopy shows optic atrophy. Which of the following is the most likely cause of this patient's symptoms?", "answer": "Dysfunction of ATP-binding cassette transporter", "options": {"A": "Deficiency of β-glucocerebrosidase", "B": "Dysfunction of ATP-binding cassette transporter", "C": "Deficiency of arylsulfatase A", "D": "Deficiency of lysosomal galactocerebrosidase", "E": "Deficiency of sphingomyelinase"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 55-year-old man comes to the physician because of a 4-month history of nocturia. He wakes up twice each night to urinate. He has no history of serious illness. He takes no medication. His younger brother was diagnosed with testicular cancer at the age of 35 years. Rectal examination shows a smooth, symmetrical prostate without nodules. The physician offers to discuss the advantages and limitations of the prostate specific antigen (PSA) test in diagnosing prostate cancer. He mentions that a a serum PSA of 4 ng/mL is generally used as a cutoff value. At this cutoff, the test has a sensitivity of 21% for detecting any prostate cancer and 51% for detecting high-risk prostate cancer, with a specificity of 91%. In patients without urinary retention, hematuria, back pain, or incontinence, the positive predictive value for PSA > 4 ng/mL is estimated at 30% and the negative predictive value for PSA ≤ 4 ng/mL at 85%. Based on this information, what is the probability that this patient does not have prostate cancer if his PSA is 4.3 ng/mL?", "answer": "70%", "options": {"A": "79%", "B": "15%", "C": "30%", "D": "70%", "E": "9%"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 23-year-old woman presents to the emergency department for vomiting and abdominal pain. The patient states that she has been unable to eat or drink for the past 24 hours without vomiting. She also complains of worsening abdominal pain that started 3 days ago. The patient has a past medical history of IV drug abuse and alcohol abuse. She is not on any current medications. Her temperature is 99.5°F (37.5°C), blood pressure is 127/68 mmHg, pulse is 120/min, respirations are 17/min, and oxygen saturation is 98% on room air. On physical exam, tenderness is elicited when the right lower quadrant of her abdomen is palpated. Deep palpation and release of the left lower quadrant of her abdomen also causes severe pain. Rectal exam reveals normal tone and stool is Guiac negative. Laboratory studies are ordered as seen below.\n\nHemoglobin: 12 g/dL\nHematocrit: 36%\nLeukocyte count: 11,500/mm^3 with normal differential\nPlatelet count: 197,000/mm^3\n\nSerum:\nNa+: 139 mEq/L\nCl-: 100 mEq/L\nK+: 4.3 mEq/L\nHCO3-: 27 mEq/L\nBUN: 20 mg/dL\nGlucose: 67 mg/dL\nCreatinine: 1.1 mg/dL\nCa2+: 10.2 mg/dL\nAST: 12 U/L\nALT: 15 U/L\n\nUrine:\nCocaine: positive\nAmphetamines: positive\nß-hCG: positive\nMarijuana: positive\nHeroin: negative\nPCP: negative\nMDMA: positive\nGlucose: negative\nKetones: negative\n\nWhich of the following is the next best step in management?", "answer": "Ultrasound", "options": {"A": "Chest radiograph", "B": "Abdominal CT", "C": "Abdominal MRI", "D": "Ultrasound", "E": "Colonoscopy"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 75-year-old man was brought in by his daughter since he was having increased incidences of forgetting things. His daughter said that he becomes increasingly frustrated searching for his glasses and keys most of the time. He was helped out a couple of times in the supermarket for forgetting the way out. He recently lost his driving license when he was spotted by the cops driving in the wrong direction on the interstate. Which of the following is the most likely pathology for this presentation?", "answer": "Abnormal cleavage of amyloid precursor protein", "options": {"A": "Prion infection", "B": "α-synuclein defect", "C": "Depigmented substantia nigra and locus cerulus", "D": "Abnormal cleavage of amyloid precursor protein", "E": "Trinucloetide repeat"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 7-month-old male child is brought into your office for recent rhinorrhea and cough. The mother states that the child has had mild fevers of up to 100.7 F over the last three days along with clear nasal discharge, and a nonproductive cough, but the child has been working harder to breathe over the last day. The mother states the child was vaccinated for the flu one month ago. His vitals are significant for a temperature of 100.9F and his physical exam is significant for intercostal retractions along with expiratory wheezing. What is the most likely organism responsible?", "answer": "Respiratory syncytial virus", "options": {"A": "Parainfluenza virus", "B": "Adenovirus", "C": "Influenza A virus", "D": "Respiratory syncytial virus", "E": "Echovirus"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 56-year-old man comes to the physician because of increasing generalized fatigue for 1 month. He also has had a 5.4 kg (12 lb) weight loss over the past 6 months. He has hypertension and type 1 diabetes mellitus. His father died of colon cancer at the age of 65 years. He has smoked one pack of cigarettes daily for 32 years and drinks one alcoholic beverage per week. He has numerous tattoos, several of which were acquired when he went backpacking through Southeast Asia as a young man. Current medications include enalapril and insulin. He is 180 cm (5 ft 11 in) tall and weighs 78 kg (172 lb); BMI is 24.1 kg/m2. His temperature is 37.0°C (98.6°F), pulse is 86/min, and blood pressure is 140/90 mm Hg. The abdomen is soft and nontender. The liver is palpated 3 cm below the right costal margin. Laboratory studies show:\nHemoglobin 12.6 g/dL\nMean corpuscular volume 86 μm3\nLeukocyte count 8800/mm3\nPlatelet count 282,000/mm3\nHemoglobin A1C 6.3 %\nSerum\nGlucose 113 mg/dL\nCreatinine 1.1 mg/dL\nAlbumin 4.1 mg/dL\nTotal bilirubin 1.1 mg/dL\nAlkaline phosphatase 66 U/L\nAST 100 U/L\nALT 69 U/L\nFerritin 180 ng/mL\nα-fetoprotein\n410 ng/mL (N < 10 ng/mL)\nCT scan of the abdomen shows a 3.5 x 2 x 1.5 cm mass in segment 6 of the liver. Which of the following interventions most likely would have prevented this patient's condition?\"", "answer": "Hepatitis B vaccination", "options": {"A": "Regular phlebotomies", "B": "Hepatitis B vaccination", "C": "Smoking cessation", "D": "Penicillamine therapy", "E": "Antitrypsin replacement therapy"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 6-year-old girl with polycystic kidney disease is started on a new medication after receiving a kidney transplant from a matched, unrelated donor. Two days after starting the medication, laboratory studies show a leukocyte count of 17,500/mm3 (90% segmented neutrophils, 4% bands, 1% eosinophils, 3% lymphocytes, and 1% monocytes). Which of the following drugs is the most likely cause of these laboratory findings?", "answer": "Methylprednisolone", "options": {"A": "Methylprednisolone", "B": "Abciximab", "C": "Ganciclovir", "D": "Erythropoietin", "E": "Tacrolimus"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A clinical trial is conducted to investigate the efficiency of a new glucagon receptor antagonist in the treatment of type 2 diabetes mellitus. After 12 weeks of treatment with this drug, all participants in the study achieved statistically significant reductions in fasting and postprandial serum glucose. Three individuals reported symptoms of hypoglycemia while exercising. The activity of which of the following cellular enzymes is most likely to be decreased in response to treatment with this drug?", "answer": "Protein kinase A", "options": {"A": "Mitogen-activated protein kinase", "B": "Janus kinase", "C": "Guanylate cyclase", "D": "Protein kinase A", "E": "Phospholipase C"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 19-year-old man is admitted to the medical intensive care unit with suspected sepsis. Blood cultures grow Gram-negative cocci containing lipooligosaccharide in their cell wall. Which of the following would you expect to find on a detailed history and physical examination of this patient?", "answer": "Petechial rash", "options": {"A": "History of consuming undercooked beef", "B": "Petechial rash", "C": "Ascending paralysis", "D": "History of exposure to rabbit hides", "E": "Rice water stools"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 25-year-old male rugby player presents to the emergency room complaining of a severe headache. He is accompanied by his teammate who reports that he had a head-to-head collision with another player and briefly passed out before regaining consciousness. His past medical history is significant for a pilocytic astrocytoma as a child treated successfully with surgery. His family history is notable for stroke in his father. His temperature is 98.9°F (37.2°C), blood pressure is 160/90 mmHg, pulse is 60/min, and respirations are 20/min. On examination, he is lethargic but oriented to person, place, and time. The affected vessel in this patient directly branches from which of the following vessels?", "answer": "Maxillary artery", "options": {"A": "Maxillary artery", "B": "Internal carotid artery", "C": "Superficial temporal artery", "D": "Middle cerebral artery", "E": "Anterior cerebral artery"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 4-year-old boy presents with 3 days of fever, crampy abdominal pain, vomiting, and loose, bloody bowel movements containing mucus. The patient’s mother says that other children from his daycare class have also developed similar symptoms. The patient’s temperature is 39.0°C (102.2°F). On physical examination, the patient is irritable and inconsolable, and his abdomen is distended. Intravenous fluid resuscitation is initiated. Histopathologic analysis of his stool reveals numerous red and white blood cells. Which of the following is characteristic of the most likely microorganism responsible for this patient’s symptoms?", "answer": "Inactivation of the 60S ribosome subunit", "options": {"A": "Inactivation of elongation factor EF-2", "B": "Inactivation of the 60S ribosome subunit", "C": "Permanent activation of Gs alpha subunit", "D": "Overactivation of guanylate cyclase", "E": "Disabling Gi alpha subunit"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 23-year-old man develops a seizure on the medical floor. He was admitted 2 days ago with high-grade fever and severe headache. At the time of admission, he had photophobia, neck rigidity, and the following vital signs: temperature 39.5°C (103.1°F), blood pressure 130/70 mm Hg, and heart rate 120/min. A cerebral spinal fluid analysis was ordered, and he was started on intravenous antibiotics. The patient’s seizure terminates without any medication or intervention. An MRI is performed which reveals dilation of all the ventricles of the brain. Which of the following is the most likely cause of his abnormal radiologic findings?", "answer": "Arachnoid granulation adhesions", "options": {"A": "Excessive cerebrospinal fluid production", "B": "Blood clot in the foramen of 3rd ventricle", "C": "Aqueductal stenosis", "D": "Arachnoid granulation adhesions", "E": "Mega cisterna magna"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 27-year-old unconscious man is brought to the ED by EMS. He was found face down in the middle of the sidewalk at 2AM. The patient is disheveled and smells of alcohol. Physical exam reveals bruising and ecchymosis at the right temple and 1-mm pupils bilaterally. His temperature 97.1°F (36.3°C), blood pressure is 84/58 mmHg, pulse is 71/min, respirations are 8/min. Following initial stabilization and respiratory support, what is the best next step for this patient?", "answer": "Naloxone", "options": {"A": "Buprenorphine", "B": "Flumazenil", "C": "Glucose", "D": "Naloxone", "E": "Warming blankets"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 43-year-old man presents to the clinic for pain with swallowing for a month. He says that the pain has gotten worse over the past few weeks. His past medical history is significant for AIDS. He states that he has not been able to afford his highly active antiretroviral therapy, so he is not currently taking any medications. His temperature is 98.6°F (37°C), respirations are 15/min, pulse is 70/min, and blood pressure is 100/84 mm Hg. Physical examination reveals no mucosal lesions. Evaluation of the blood reveals:\nHb%: 11 gm/dL\nTotal count (WBC): 2,400 /mm3\nDifferential count:\nNeutrophils: 70%\nLymphocytes: 25%\nMonocytes: 5%\nCD4+ cell count: 51/mm3\nWhat is the best pharmacotherapy for this patient's current symptom?", "answer": "Oral fluconazole", "options": {"A": "Oral fluconazole", "B": "Oral nystatin liquid suspension", "C": "Intravenous amphotericin B", "D": "Oral acyclovir", "E": "Intravenous ganciclovir"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 25-year-old man is brought by his roommate to the emergency department with chest pain, which began 90 minutes ago. His roommate says that he has not slept within the past 24 hours and has been taking pills to help him study longer for his upcoming national dental board exam. On examination, he is diaphoretic, extremely agitated, and attempts to remove his IV lines and ECG leads. His temperature is 38.9°C (102.2°F), pulse is 115/min, and blood pressure is 160/102 mmHg. His pupil size is 7 mm bilaterally. The lungs are clear to auscultation. The most appropriate next step in management is administration of which of the following?", "answer": "Lorazepam", "options": {"A": "Lorazepam", "B": "Dantrolene", "C": "Activated charcoal", "D": "Ketamine", "E": "Haloperidol\n\""}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 65-year-old female presents to her primary care physician for a routine check-up. She reports feeling well but has noticed occasional weakness and constipation over the past few months. A complete blood count is within normal limits. Serum calcium is 11.9 mg/dL and serum phosphate is 2.4 mg/dL. Urine calcium output is 400 mg/24 h. A sestamibi scan demonstrates increased uptake near the inferior left pole of the thyroid gland. Which of the following mechanisms is most likely involved in this patient’s symptoms?", "answer": "Increased RANK-L expression", "options": {"A": "Increased osteoprotegerin expression", "B": "Decreased RANK-L expression", "C": "Increased RANK-L expression", "D": "Increased ß-adrenergic receptor synthesis", "E": "Decreased M-CSF synthesis"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 35-year-old male presents to his physician with a small mass that he found in the anterior of his neck a few days ago. The mass is not painful and does not affect his swallowing. He noticed no change in his weight. His history is significant for radiation exposure for treating his neuroblastoma at the age of 15. On examination, a nodule around the size of 2.2 cm is palpated in the right thyroid lobule; the nodule is firm and non-tender. There is cervical lymphadenopathy. His blood pressure is 118/75 mm Hg, respirations are 17/min, pulse is 67/min, and temperature is 37.5°C (99.5°F). Laboratory findings include serum Na+ of 136 mmol/L, K+ of 4.2 mmol/L, Cl– of 90 mmol/L, and bicarbonate of 24 mmol/L. Which of the following factors will most likely make the prognosis worse in this patient?", "answer": "Bone metastases", "options": {"A": "Age", "B": "Bone metastases", "C": "Palpable lymph nodes", "D": "Follicular histological variant", "E": "Hurthle cell variant"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "An 18-year-old man is referred to a psychiatrist for evaluation after a recent suicide attempt. On questioning him, he says that he did it because he got fed up with life and feels that he is worthless. The patient’s father informs the doctor that his son has been gloomy most of the time over the last 2 months, and his academic performance has declined significantly. His father further adds that his son’s appetite has decreased significantly over the last 3 months, leading to a 5.0 kg (11.0 lb) weight loss.  The patient denies any history of manic or hypomanic episodes. Physical examination is unremarkable. Routine laboratory tests, including thyroid hormone and cortisol levels, are within normal limits. Which of the following patterns of abnormal brain activity would most likely be present in this patient?", "answer": "Decreased norepinephrine levels in the cortical and limbic areas", "options": {"A": "Increased serotonergic activity in frontal cortex", "B": "Increased dopaminergic activity in the limbic system", "C": "Increased glutamatergic activity in the subthalamic nucleus", "D": "Decreased norepinephrine levels in the cortical and limbic areas", "E": "Decreased cholinergic activity in the hippocampus and amygdala"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 10-year-old girl is evaluated for a suspected primary deficiency. She is the first child in a consanguineous marriage. She was born vaginally at full term after an uncomplicated pregnancy and was breastfed for 9 months. The patient has had an episode of meningococcal meningitis, recurrent bronchiolitis, and multiple bouts of pneumococcal pneumonia over the past 5 years. She has also suffered from chronic otitis media since the age of 5. After a thorough examination, the child is found to have a partial CD19 deficiency. Which of the following proteins is heavily involved with this pathogenesis?", "answer": "CD21", "options": {"A": "CD155", "B": "CD8", "C": "CD16", "D": "CD21", "E": "CD25"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 24-year old woman is brought to the emergency department after a motor vehicle collision. She was a restrained passenger at the time of impact. On examination, the patient is pale and in moderate distress. She complains of a sharp pain in the posterior aspect of the left shoulder. Vitals include temperature is 37.0°C (98.6°F), right arm blood pressure is 94/63 mm Hg, left arm blood pressure is 90/61 mm Hg, pulse is 122/min, and respirations are 24/min. Cardiopulmonary auscultation reveals normal heart sounds and clear lungs. Neck veins are not distended. Several, large ecchymoses are visible over the chest and abdomen in a seatbelt pattern. Her abdomen is tender on superficial palpation with mild rebound tenderness and rigidity. Her range of motion is normal with 5/5 motor strength in all extremities. Wrist drop is absent. A FAST scan is pending. Based on the patient’s current presentation, which organ is most likely affected?", "answer": "Spleen", "options": {"A": "Pancreas", "B": "Heart", "C": "Spleen", "D": "Gallbladder", "E": "Appendix"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 68-year-old woman presents to her primary care physician with complaints of fatigue, difficulty breathing upon exertion, and crampy lower abdominal pain. She also notices that her stools are dark. She has had essential hypertension for 20 years for which she takes bisoprolol. Her family history is positive for type 2 diabetes mellitus. On physical examination, she looks pale. Complete blood count shows the following:\nHemoglobin 10 g/dL\nMean corpuscular volume (MCV) 70 fL\nMean corpuscular hemoglobin (MCH) 25 pg/cell\nMean corpuscular hemoglobin concentration (MCHC) 27 g/dL\nRed cell distribution width 16%\nPlatelet count 350,000/mm3\nSerum ferritin is 9 ng/mL. The patient is referred to a gastroenterologist and conventional colonoscopy reveals a polypoid mass in the ascending colon. Biopsy shows poorly differentiated adenocarcinoma. A preoperative staging is performed and a laparoscopic cancer resection with postoperative chemotherapy are planned. Which of the following tests can be used for postoperative follow up of this patient?", "answer": "Carcinoembryonic antigen (CEA)", "options": {"A": "Liver biochemistry", "B": "Carcinoembryonic antigen (CEA)", "C": "Pelvic magnetic resonance imaging (MRI)", "D": "Transrectal endoscopic ultrasound (TRUS)", "E": "Cancer antigen 125 (CA 125)"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 34-year-old man comes to the physician because of a 2-day history of progressively blurred vision. He also reports seeing flashing lights in his visual field. He does not have any pain. The patient has not been examined by a physician in several years. He appears emaciated. Examination shows right conjunctival injection. Visual acuity is 20/20 in the left eye and 20/100 in the right eye. Fundoscopic examination of the right eye is shown. His CD4+ T-lymphocyte count is 46/mm3. Which of the following is the most appropriate pharmacotherapy for this patient's eye condition?", "answer": "Valganciclovir", "options": {"A": "Valganciclovir", "B": "Penicillin G", "C": "Famciclovir", "D": "Sulfadiazine and pyrimethamine", "E": "Trimethoprim-sulfamethoxazole"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 42-year-old man comes to the physician because of several episodes of rectal bleeding over 2 weeks. He has had pain around the anal area for the past month. Six months ago, he was diagnosed with esophageal candidiasis and was treated with oral fluconazole. He is HIV-positive. He has had 9 male sexual partners over his lifetime and uses condoms inconsistently. The patient's current medications include dolutegravir, tenofovir, and emtricitabine. He is 179 cm (5 ft 10 in) and weighs 66 kg (146 lb); BMI is 20.9 kg/m2. Vital signs are within normal limits. Digital rectal examination and anoscopy show a hard 2-cm mass palpable 0.5 cm above the anal verge that bleeds on contact. There is no inguinal lymphadenopathy. The abdomen is soft and nontender. The CD4+ T-lymphocyte count is 95/mm3(N ≥ 500/mm3). A biopsy confirms the diagnosis. This patient is most likely to benefit from which of the following interventions?", "answer": "Radiochemotherapy", "options": {"A": "Radiochemotherapy", "B": "Local 5-fluorouracil therapy", "C": "Total mesorectal excision", "D": "Injection sclerotherapy", "E": "Submucosal hemorrhoidectomy\n\""}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 19-month-old boy comes into the emergency department with his parents. He has burns on his buttocks and perineal area. The patient’s mother says she was at home with the patient when she heard him screaming from the kitchen. She says she ran to the room to find that the patient had pulled down a container of hot water on himself. Which of the following burn patterns would be most indicative of child abuse in this patient?", "answer": "Circular burns of equal depth restricted to the buttocks, with sparing of the hands and feet", "options": {"A": "Burns to flexor and anterior surfaces", "B": "Burns with irregular borders, uneven depth of burns, and splash pattern", "C": "Burns with some areas blistering but with others not blistering", "D": "Circular burns of equal depth restricted to the buttocks, with sparing of the hands and feet", "E": "Non-circumferential burns"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 44-year-old woman presents to the physician for evaluation of recurrent episodes of pounding headache, palpitations, excessive sweating, anxiety, tremors, and pallor, with occasional vomiting for the last 2 weeks. She has presented to the same physician with similar complaints in the past; however, she is frustrated with the lack of proper diagnosis and now insists on a detailed workup. She does not take any medications. She has a history of progressively increasing thyroid swelling as well as multiple bone pain for the past 2 months. On physical examination, she is very lean and appears anxious and apprehensive. She has clammy and moist hands. Her temperature is 37.1°C (98.9°F), the pulse is 110/min, the blood pressure is 176/94 mm Hg, and the respiratory rate is 27/min. Her weight is 43 kg (94.8 lb), height is 145 cm (4 ft 7 in), and body mass index (BMI) is 20.4 kg/m2. A firm thyroid nodule is palpable in the right lobe. Physical examination is otherwise normal. What is the most appropriate initial management for this patient?", "answer": "24-h urine catecholamine by-products (vanillylmandelic acid (VMA), metanephrine, and normetanephrine)", "options": {"A": "Serum epinephrine and norepinephrine", "B": "Clonidine test", "C": "CT scan/MRI of the abdomen", "D": "24-h urine catecholamine by-products (vanillylmandelic acid (VMA), metanephrine, and normetanephrine)", "E": "Serum calcium and PTH"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 54-year-old male is involved in a high speed motor vehicle collision and is brought to the emergency department. On arrival, his vitals are temperature 98.6 °F (37 °C), blood pressure 110/70 mmHg, pulse 100/min, and respirations are 20/min. His Glasgow Coma Score (GCS) is 13 (eye opening 3, verbal response 5, and motor response 5). Physical exam is notable for a rapid and thready pulse, and a rigid and distended abdomen with positive rebound tenderness. FAST exam reveals a large hypoechoic stripe in the hepatorenal recess. Two large bore IV's are started and the patient is given a 1L bolus of normal saline. The patient’s mental status rapidly deteriorates and he becomes unresponsive. His pulse is 149/min and blood pressure is 70/40 mmHg. The patient is started on a medication while additional fluids are administered. Subsequently his vitals, his pulse is 80/minute and blood pressure is 120/80 mmHg. While the patient is being taken to the operating room, he develops pain in all four distal extremities. His digits appear blue and are cool to the touch. Which medication is most likely responsible for this complication?", "answer": "Norepinephrine", "options": {"A": "Epinephrine", "B": "Dobutamine", "C": "Norepinephrine", "D": "Vasopressin", "E": "Ephedrine"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 20-year-old man with a history of cystic fibrosis presents to his pulmonologist for a regular checkup. He generally feels well but noticed that he has had an increase in stool frequency. He describes his stools as loose and “greasy”, often staining the toilet bowl. He regularly uses albuterol and budesonide inhalers and has chest physical therapy several times a month. Physical exam is unremarkable. Serum level of which of the following coagulation factors is likely abnormal in this patient?", "answer": "II", "options": {"A": "II", "B": "V", "C": "VIII", "D": "XI", "E": "XII"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 6-year-old boy is brought to the physician by his father for an annual health maintenance examination. His father notes that he has several pigmented areas on his skin and a few fleshy bumps. He has also had some blurred vision in his left eye. He has no history of serious medical illness. He lives at home with both parents and is up-to-date on all his immunizations. His father has similar skin findings. His mother has epilepsy and glaucoma. Vital signs are within normal limits. Visual acuity testing shows 20/50 in the left eye and 20/20 in the right eye. Slit-lamp examination shows pigmented iris nodules. Examination of his skin shows eight brownish macules and numerous soft, non-tender, pedunculated lesions on the back, chest, and abdomen. Which of the following is the most appropriate next step in management?", "answer": "MRI of the brain", "options": {"A": "CT scan of the brain", "B": "MRI of the brain", "C": "Electroencephalogram", "D": "B-scan ultrasound", "E": "Gonioscopy"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 43-year-old man is brought to the emergency department because of a fever, cough, pleuritic chest pain, and dyspnea. Two days ago, he returned from a construction site along the Mississippi River. Abdominal examination shows a palpable spleen. An x-ray of the chest shows diffuse reticulonodular infiltrates. Therapy with a drug that binds ergosterol is initiated. This patient is most likely to experience which of the following adverse effects?", "answer": "Hypomagnesemia", "options": {"A": "Hypomagnesemia", "B": "Histamine release", "C": "Leukopenia", "D": "Dysgeusia", "E": "Cytochrome P450 induction"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 49-year-old African man presents to the physician with a 3-month history of fatigue, shortness of breath, and abdominal distention. He immigrated to the US approximately 6 months ago. He has no other medical problems and is currently not on medication. He previously worked as a farmer but stopped due to his inability to keep up with the work. His blood pressure is 112/58 mm Hg, pulse is 90/min, respiratory rate is 19/min, and temperature is 37.8°C (100.0°F). Physical examination reveals bilateral pedal edema up to the knees, jugular venous distention, and abdominal distention with free fluid. Chest auscultation reveals the following sound. Jugular venous pressure tracing reveals prominent ‘x’ and ‘y’ descents. Radial pulse is absent during inspiration bilaterally. Which of the following is the primary underlying cause of this patient’s presentation?", "answer": "Tuberculosis", "options": {"A": "Coxsackie A virus", "B": "Tuberculosis", "C": "Cor pulmonale", "D": "Protozoan infection", "E": "Tricuspid endocarditis"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 25-year-old primigravida is admitted to the hospital at 35 weeks gestation with lower leg edema. She denies any other symptoms. Prior to admission, the antepartum course was unremarkable and she was compliant with recommended  prenatal care. The vital signs were as follows: blood pressure, 155/90 mm Hg; heart rate, 84/min; respiratory rate, 16/min; and temperature, 36.6℃ (97.9℉). The fetal heart rate was 142/min. The physical examination shows 2+ pitting edema. A 24-hour urine assessment showed proteinuria (1.2 g). An ultrasound examination showed a normally developing fetus without structural abnormalities. The placental margin was located 3 cm away from the internal os. Which of the following options describes the  proper management in this patient assuming that no deterioration occurs up to the time of delivery?", "answer": "Induction of vaginal delivery at 37 weeks’ pregnancy if not begin spontaneously earlier", "options": {"A": "Induction of vaginal delivery at 37 weeks’ pregnancy if not begin spontaneously earlier", "B": "Cesarean delivery after a course of a corticosteroid treatment", "C": "Vaginal delivery induction after a course of corticosteroid treatment", "D": "Cesarean delivery at 37 weeks’ pregnancy or urgently after beginning of spontaneous delivery if it is earlier", "E": "Watch for a spontaneous vaginal delivery at any term from the moment of presentation"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 12-year-old female presents to the emergency room difficult to arouse and occasionally vomiting. On physical exam, her oral mucosa looks dry, her breath has a fruity odor, and her breathing is slow, deep and labored. What is the most likely primary metabolic disturbance?", "answer": "Anion gap metabolic acidosis", "options": {"A": "Anion gap metabolic acidosis", "B": "Non-anion gap metabolic acidosis", "C": "Metabolic alkalosis", "D": "Respiratory alkalosis", "E": "Respiratory acidosis"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 36-year-old man presents to the emergency room with subacute worsening of chronic chest pain and shortness of breath with exertion. The patient is generally healthy, lifts weights regularly, and does not smoke. His temperature is 97.8°F (36.6°C), blood pressure is 122/83 mm Hg, pulse is 80/min, respirations are 13/min, and oxygen saturation is 98% on room air. Cardiac auscultation reveals a crescendo-decrescendo murmur heard right of the upper sternal border with radiation into the carotids. An ECG shows left axis deviation and meets criteria for left ventricular hypertrophy. An initial troponin is < 0.01 ng/mL. Which of the following is the most likely diagnosis?", "answer": "Bicuspid aortic valve", "options": {"A": "Bacterial endocarditis", "B": "Bicuspid aortic valve", "C": "Cardiac myxoma", "D": "Mitral insufficiency", "E": "Senile calcific changes"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 66-year-old man is admitted to the intensive care unit for management of laboratory-confirmed septic shock. His current plan includes appropriate management of airway and breathing, intravenous antibiotics, fluid resuscitation, and supportive care. After the administration of adequate intravenous isotonic fluids, his temperature is 37.2°C (99.0°F), the pulse rate is 120/min, the blood pressure is 90/50 mm Hg, and the respiratory rate is 22/min. His extremities are warm and capillary refill time is normal. The patient is started on vasopressor therapy, and norepinephrine is chosen over epinephrine. Which of the following characteristics of norepinephrine best explains this choice in this patient?", "answer": "Norepinephrine has more α1-adrenergic effects compared to epinephrine", "options": {"A": "Norepinephrine has less α1-adrenergic effects compared to epinephrine", "B": "Norepinephrine has more β2-adrenergic activity compared to epinephrine", "C": "Norepinephrine has similar effects on β2 adrenergic receptors compared to epinephrine", "D": "Norepinephrine has similar α1-adrenergic effects compared to epinephrine", "E": "Norepinephrine has more α1-adrenergic effects compared to epinephrine"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 67-year-old man comes to the physician because of a worsening tremor that began one year ago. The tremor affects his left hand and improves when he uses his hand to complete a task. He also reports feeling stiffer throughout the day, and he has fallen twice in the past year. He has not noticed any changes in his cognition or mood. He has not had difficulty sleeping, but his wife says that he would kick and punch while dreaming for almost a decade. He drinks two cans of beer daily. He takes no medications. He appears healthy and well nourished. His vital signs are within normal limits. He maintains a blank stare throughout the visit. Further evaluation is most likely to show which of the following?", "answer": "Reduced amplitude on foot tapping", "options": {"A": "Reduced amplitude on foot tapping", "B": "Startle myoclonus", "C": "Extensor plantar response", "D": "Choreiform movements", "E": "No abnormalities\n\""}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 25-year-old African American man comes to the emergency department for “red urine.” Patient reports that he just returned from a skiing trip in the Rocky Mountains and developed the reddish urine today. He denies upper respiratory infection symptoms, chest pain, fever, or chills but does endorse some right flank pain that developed 3 days ago. Physical examination was unremarkable except for some tenderness upon palpation at the right flank. Laboratory findings are as follows:\n\nSerum:\nNa+: 137 mEq/L\nK+: 4.9 mEq/L\nCl-: 100 mEq/L\nHCO3-: 25 mEq/L\nOsmolality: 275 Osm/kg\n\nUrine:\nColor: Red\nProtein: 3+\nRBC: 4 cells/hpf\nOsmolality: 214 Osm/kg\nSpecific gravity: 1.004\n\nWhich finding would you most likely expect with this patient?", "answer": "HbS on hemoglobin electrophoresis", "options": {"A": "Cystic mass of the right kidney on CT abdomen/pelvis", "B": "HbS on hemoglobin electrophoresis", "C": "Linear deposition of IgG antibodies on renal electron microscopy", "D": "Renal stones on CT abdomen/pelvis", "E": "Segmental sclerosis and hyalinosis of renal glomeruli on light microscopy"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 62-year-old man presents to his primary care physician because of lower back pain and radiating leg pain. He says that the pain is searing and goes from the buttock into the posterior thigh and lateral leg. It is moderate in intensity and he has noticed that it worsens with sitting and improves with standing. His past medical history is significant for well controlled hypertension, but he has otherwise been healthy. He works as a laborer loading packages in a warehouse and is concerned because the pain does not allow him to work. On physical exam, he is found to have pain and paresthesia while performing a straight leg raise. Radiographs show loss of disk height and MRI shows significant degeneration and posterolateral herniation of the disk in between the L5 and S1 vertebrae. Adjacent disks appear to be relatively normal without notable herniation. Which of the following sets of findings would most likely be seen in this patient?", "answer": "Weak ankle plantarflexion and diminished Achilles reflex", "options": {"A": "Weak ankle dorsiflexion and diminished Achilles reflex", "B": "Weak ankle dorsiflexion and hallucis extension", "C": "Weak ankle plantarflexion and diminished Achilles reflex", "D": "Weak ankle plantarflexion and diminished patellar reflex", "E": "Weak ankle plantarflexion and hallucis extension"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 46-year-old woman presents to her primary care provider with pain in both of his hands and wrists. She notes that it is hard for her to prepare breakfast or wash dishes in the morning due to stiffness. It seems to subsides later in the day. She also complains of a constant fatigue and unintentional weight loss during the last few months. The past medical history is significant for hypertension. She takes captopril and aspirin daily, and occasional ibuprofen for the pain in her hands. Her mother developed similar symptoms in her hands resulting in hand deformity. The blood pressure is 140/90 mm Hg, heart rate is 67/min, respiratory rate is 13/min, and temperature is 37.0°C (98.6°F). Physical examination shows redness, edema, and tenderness on palpation at the metacarpophalangeal and proximal interphalangeal joints of both hands. The blood tests show the following findings:\nRed blood cell count 3.3 million/mm3\nHb 12.1 mg/dL\nLeukocyte count 10,101/mm3\nESR 48 mm/h\nC-reactive protein 3.9 mg/L\nAnti-cyclic citrullinated peptide 45 μ/mL\nWhich of the following medications is first-line therapy to slow disease progression?", "answer": "Methotrexate", "options": {"A": "Intra-articular corticosteroid injections", "B": "Methotrexate", "C": "Azathioprine", "D": "Meloxicam", "E": "Etanercept"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 27-year-old woman presents to her primary care physician’s office complaining of trouble sleeping. She reports that for the past 10 months she has experienced difficulty falling asleep due constant worrying. The content of her worry include items such as whether or not her child will feel lonely in day care and the health of her parents. These worrying episodes typically begin toward the end of the day and last for several hours. She states that she has trouble concentrating at work as well and describes her heart as \"racing\" during these episodes. She denies any alcohol or illicit drug use. Which of the following neurotransmitters is most likely decreased in this patient?", "answer": "GABA", "options": {"A": "Acetylcholine", "B": "Dopamine", "C": "GABA", "D": "Norepinephrine", "E": "Glutamate"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 10-year-old boy is brought to the physician because of fever and bloody diarrhea for the past few days. His parents report that he has become increasingly lethargic and irritable. His temperature is 38.6°C (101.4°F), pulse is 102/min, and respirations are 22/min. He has no significant past medical history. His parents say that he mostly only eats a diet of chicken, hamburgers, fries, cheese, and milk. On physical examination, pallor and edema in both legs are present. His laboratory studies show:\nHemoglobin 8.9 gm/dL\nLeukocyte count 9,300/mm3\nPlatelet count 67,000/mm3\nBlood urea nitrogen 43 mg/dL\nSerum creatinine 2.46 mg/dL\nCoombs test Negative\nWhich of the following is the most likely diagnosis?", "answer": "Escherichia-induced hemolytic uremic syndrome", "options": {"A": "Thrombotic thrombocytopenic purpura", "B": "Genetic form of hemolytic uremic syndrome", "C": "Hemolytic uremic syndrome associated with systemic disease", "D": "Escherichia-induced hemolytic uremic syndrome", "E": "Pneumococci-induced hemolytic uremic syndrome"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 50-year-old white male who works in construction comes to your office because of pain in his upper arm. He states that over the last few months, he has been having pain in his upper arm that worsens with raising objects overhead. He states that he also recently fell on his outstretched hand and that seemed to worsen his pain. His vital signs are within normal limits. He has no pain on internal or external rotation. He also had no pain with the lift off test, but does have significant pain with the empty can test and the arm drop test. Which structure has he most likely injured?", "answer": "Supraspinatus tendon", "options": {"A": "Pectoralis major tendon", "B": "Deltoid muscle", "C": "Supraspinatus tendon", "D": "Infraspinatus tendon", "E": "Subscapularis tendon"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 76-year-old man presents to the physician with a severe, pruritic rash as shown in the image. He has lost sleep over the past week because of itchiness and discomfort. He has not noticed any insect bites. He is not experiencing any pain. He currently lives in an elderly home where several other residents are experiencing a similar problem. He has no history of a serious illness and does not take any medications. His vital signs are within normal limits. A similar rash is seen on his face and below the knees on both sides. The skin of the groin, genital and perianal area, buttocks, and thighs show no abnormalities. The remainder of the physical examination is unremarkable. Which of the following pathogens is the most likely cause of this patient’s condition?", "answer": "Cimex lectularius", "options": {"A": "Cimex lectularius", "B": "Dermatobia hominis", "C": "Varicella zoster", "D": "Lice", "E": "Sarcoptes scabiei"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 6-month-old girl is brought to the hospital by her parents for evaluation due to poor feeding for the last month. Her parents say that she has not been eating well over the last two months, yet her abdomen has grown larger. Physical exam shows a thin female infant with an enlarged liver and palpable spleen. Eye exam reveals a red spot on the retina. She has an intact muscle tone and reflexes. Which of the following enzymes is deficient in this patient?", "answer": "Sphingomyelinase", "options": {"A": "Hexosaminidase A", "B": "α-galactosidase A", "C": "Glucocerebrosidase", "D": "Sphingomyelinase", "E": "Galactocerebrosidase"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 24-year-old female is brought to the ED from a nearby nightclub by the local police due to aggressive and violent behavior over the past hour. A friend accompanying the patient reports that the patient smoked marijuana that \"seemed different\" approximately one hour ago. The patient has never had this kind of reaction to marijuana use in the past. On examination, the patient is combative with slurred speech and active visual hallucinations; eye examination shows prominent vertical nystagmus. This patient's presentation can be best explained by intoxication with a substance that acts at which of the following receptors?", "answer": "NMDA", "options": {"A": "Serotonin", "B": "Cannabinoid", "C": "GABA", "D": "NMDA", "E": "Norepinephrine"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 2-month-old infant comes to the clinic because of progressive weakness and fatigue over the past 4 weeks. He is his mother’s first-born boy. She was in Mexico during the delivery and says that she had a regular 39-week gestation. She took folic acid during her pregnancy. The infant was born through vaginal delivery with no complications. Apgar scores were 10 and 9 at 1 and 5 minutes, respectively. The neonate did not go through a newborn screening process. His pulse is 130/min, respiratory rate is 43/min, temperature is 37.2°C (99.0°F), and blood pressure is 90/60 mm Hg. Physical examination shows lethargy, hypotonia, and a weak response to primitive reflexes. There is a “honey-like” odor around his diaper which the mother says has been present since birth. Which of the following enzymes is most likely deficient in this patient?", "answer": "Branched-chain alpha-ketoacid dehydrogenase", "options": {"A": "Branched-chain alpha-ketoacid dehydrogenase", "B": "Cystathionine synthase deficiency", "C": "Homogentisic acid oxidase", "D": "Phenylalanine hydroxylase", "E": "Propionyl-CoA carboxylase"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 35-year-old engineer is told by his boss that his team will need to work extra evening hours in the coming week in order to meet a project deadline. This frustrates the engineer, who already feels he is working too many hours. Instead of discussing this directly with his boss, the engineer calls in sick and leaves his work for his boss to finish. Which of the following psychological defense mechanisms is this individual demonstrating?", "answer": "Passive aggression", "options": {"A": "Anticipation", "B": "Displacement", "C": "Acting out", "D": "Passive aggression", "E": "Blocking"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 29-year-old woman comes to the physician because of a 4-month history of fever, progressive shortness of breath, and a dry cough. During this time, she has also had a 5-kg (11-lb) weight loss. Two months ago, she was in Kenya for several weeks to visit her family. Physical examination shows fine crackles and wheezing over both lung fields. Her serum calcium concentration is 11.8 mg/dL. An x-ray of the chest shows reticular opacities in both lungs and bilateral hilar lymphadenopathy. Which of the following is the most likely underlying mechanism of this condition?", "answer": "Granulomatous inflammation", "options": {"A": "Necrotizing inflammation", "B": "Granulomatous inflammation", "C": "Viral infection", "D": "Monoclonal plasma cell production", "E": "Neoplastic transformation\n\""}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 58-year-old man undergoes coronary angiography that demonstrates a 90% stenosis of the left anterior descending coronary artery. The circumflex branch of the left coronary artery is not significantly obstructed. Prior to the angiogram, he underwent a pharmacologic cardiac stress test. When administered, the pharmacologic agent caused the left circumflex artery to vasodilate, with resulting increased blood supply to its supplied myocardium that was already well-perfused at baseline. This increased flow through the circumflex artery shunted blood flow away from the myocardium supplied by the stenosed left anterior descending artery, resulting in ischemia that manifested as a perfusion defect on radionuclide imaging. Which of the following agents is most strongly associated with this phenomenon described above?", "answer": "Dipyridamole", "options": {"A": "Metoprolol", "B": "Verapamil", "C": "Diltiazem", "D": "Carvedilol", "E": "Dipyridamole"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 51-year-old woman comes to the physician because of a 3-week history of fatigue, non-productive cough, and worsening shortness of breath while walking. She was diagnosed with HIV 11 years ago. Two years ago, she was treated for esophageal thrush with fluconazole. She takes no medications because she does not feel like she needs them. She occasionally uses intravenous illicit drugs and has smoked a pack of cigarettes daily for 35 years. She appears ill. Her temperature is 38.4°C (101.1°F), respiratory rate is 25/min, pulse is 116/min, and blood pressure is 115/70 mm Hg. Pulse oximetry shows an oxygen saturation of 89% on room air. Inspiratory crackles are heard over bilateral lung fields. Cardiac examination shows no abnormalities. Laboratory studies show a CD4 count of 67/mm3 (N ≥ 500/mm3) and an elevated HIV viral load. An x-ray of the chest shows diffuse interstitial infiltrates bilaterally. In addition to starting antiretroviral therapy, the appropriate treatment for her current illness is initiated. Maintaining the patient on this medication to prevent recurrence of her current illness will also prevent infection with which of the following pathogens?", "answer": "Toxoplasmosa gondii", "options": {"A": "Varicella zoster virus", "B": "Toxoplasmosa gondii", "C": "Cryptococcus neoformans", "D": "Cytomegalovirus", "E": "Candida albicans"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 37-year-old man presents with right lower extremity weakness and low back pain. The patient states that he has had chronic mild to moderate low back pain for several years, but, 3 days ago after lifting a box, the pain increased in intensity and spread to his right leg. He describes the pain as severe, electrical in character, and descending from his right gluteal region along his right posterior thigh and leg to his right lateral ankle and foot. The patient also says that he has been having difficulty walking due to stumbling over his right foot. His temperature is 37.0℃ (98.6℉), the blood pressure is 125/80 mm Hg, the pulse is 72/min, the respiratory rate is 16/min, and the oxygen saturation is 98% on room air. On physical examination, the patient is alert and cooperative. Musculoskeletal examination of the lower extremities shows the following results:\nFunctional Muscle Group/DTR Tested Right Side Left Side\n               Strength\nHip extension 5/5 5/5\nHip abduction 4/5  5/5\nHip adduction  5/5  5/5\nHip flexion 5/5 5/5\nKnee flexion 5/5 5/5\nKnee extension 5/5 5/5\nFoot plantar flexion 5/5 5/5\nFoot dorsiflexion 4/5 5/5\nFoot inversion 4/5 5/5\nFoot eversion 4/5 5/5\nToe extension 3/5 5/5\n              Reflexes\nKnee 3+ 3+\nAchilles 1+ 3+\nPlantar 2+ 3+\n               Sensory\nSensation Decreased on the lateral aspect of the lower leg and dorsum of the foot Normal over all the surface\nLassegue test Positive at 30 deg. Negative\nWhich of the following is the most likely mechanism giving rise to this patient’s condition?", "answer": "Protrusion of the L4/L5 intervertebral disk", "options": {"A": "Protrusion of the L4/L5 intervertebral disk", "B": "Entrapment of the femoral nerve in the femoral canal", "C": "Compression of the sciatic nerve by piriform muscle", "D": "Inflammation of the S2-3 spinal roots", "E": "Herniation of the L2/3 intervertebral disk"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 21-year-old woman comes to the physician because of a 5-day history of pain with urination and vaginal itching. She is sexually active with multiple partners and uses condoms inconsistently. Pelvic examination shows erythema of the vulva and vaginal mucosa, punctate hemorrhages on the cervix, and green-yellow, malodorous discharge. A photomicrograph of the discharge is shown. Which of the following is the most likely causal organism?", "answer": "Trichomonas vaginalis", "options": {"A": "Neisseria gonorrhoeae", "B": "Treponema pallidum", "C": "Chlamydia trachomatis", "D": "Candida albicans", "E": "Trichomonas vaginalis"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 9-year-old girl has recently begun having daily staring-spells in which she becomes unresponsive for several seconds. Following these episodes, she rapidly returns to normal with no recollection of the event. Her performance in school has begun to deteriorate. The child's pediatrician refers her to a pediatric neurologist, and, after an appropriate neurological work-up, the child is diagnosed with absence seizures. Her neurologist recommends initiating an anti-seizure medication, but the patient adamantly refuses due to fear of side effects and her belief that the condition is not affecting her quality of life. Which of the following is the most appropriate next step?", "answer": "Obtain consent from one parent before initiating therapy", "options": {"A": "Do not initiate therapy at this time", "B": "Prescribe a long acting depot medication", "C": "Discuss the patient's school performance with her teachers", "D": "Obtain consent from one parent before initiating therapy", "E": "Obtain consent from both parents before initiating therapy"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 44-year-old woman comes to the physician because of pain and swelling below her left eye for 3 days. She has also had excessive watering from her eyes during this period. She has no history of serious illness and takes no medications. Her temperature is 37°C (98.6°F), pulse is 90/min, and blood pressure is 110/70 mm Hg. Examination shows erythema, tenderness, warmth, and swelling below the medial canthus of the left eye. There is purulent discharge from the lower lacrimal punctum on palpation of the swelling. The remainder of the examination shows no abnormalities. The discharge is sent for cultures. Which of the following is the most appropriate next step in management?", "answer": "Oral amoxicillin-clavulanate therapy", "options": {"A": "Topical ciprofloxacin", "B": "Intravenous ceftriaxone", "C": "Irrigation of lacrimal cannaliculi", "D": "Oral amoxicillin-clavulanate therapy", "E": "CT scan of the orbit\n\""}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 40-year-old man comes to the physician because of decreased sexual arousal and erectile dysfunction that has put strain on his marriage for the last year. He has also had fatigue and generalized weakness for the past 9 months. He has noticed his bowel movements have not been as frequent as usual. He has occasional dry coughing and back pain. He has not had fever, headache, or changes in vision. One year ago, he traveled to South Africa with his wife. He looks fatigued. He is 168 cm (5 ft 6 in) tall and weighs 89 kg (196 lb); BMI is 31.6 kg/m2. His temperature is 36.5°C (97.7°F), pulse is 50/min, and blood pressure is 125/90 mm Hg. Physical examination shows dry skin and a distended abdomen. Neurological examination reveals delayed deep tendon reflexes. Laboratory studies show:\nHemoglobin 11.0 g/dL\nPlatelet count 380,000/mm3\nSerum\nNa+ 130 mEq/L\nCl- 97 mEq/L\nK+ 4.5 mEq/L\nHCO3- 25 mEq/L\nGlucose 95 mg/dL\nTSH 0.2 μU/mL\nWhich of the following is the most likely cause of these findings?\"", "answer": "Pituitary adenoma", "options": {"A": "Hemochromatosis", "B": "Tuberculosis", "C": "Pituitary adenoma", "D": "Graves disease", "E": "Hashimoto thyroiditis"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 52-year-old man with limited, unresectable small cell lung cancer comes to the emergency department because of fever for the past 2 days. He has been on numerous chemotherapy regimens. His last round of treatment was with cisplatin and etoposide and ended 10 days ago. He feels fatigued but has not had nausea or vomiting. His temperature is 38.5°C (101.3°F), blood pressure is 100/60 mm Hg, and pulse is 115/min. The lungs are clear to auscultation. Examination shows a soft, nontender abdomen. Laboratory studies show:\nHemoglobin 10.2 g/dL\nLeukocyte count 4,000/mm3\nTotal neutrophils 8%\nEosinophils 2%\nLymphocytes 80%\nMonocytes 10%\nUrinalysis shows no abnormalities. Blood culture samples are obtained. Which of the following is the most appropriate next step in management?\"", "answer": "Cefepime", "options": {"A": "Cefepime", "B": "Piperacillin", "C": "Clindamycin", "D": "Bronchoscopy with bronchoalveolar lavage", "E": "High-resolution chest CT"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 28-year-old woman presents in respiratory distress. Auscultation of the lungs reveals bilateral crepitations and a friction rub. Lab findings show pancytopenia, proteinuria, and a false-positive test for syphilis. A chest X-ray shows bilateral pleural effusions. Which of the following findings are most likely?", "answer": "Photosensitivity", "options": {"A": "Photosensitivity", "B": "Urethritis", "C": "Xerostomia", "D": "Esophageal dysmotility", "E": "Aortitis"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 2-month-old infant is brought in by his mother for runny nose and cough. She reports he had an ear infection 2 weeks ago, and since then he has had a productive cough and nasal congestion. His medical history is significant for multiple ear infections and eczematous dermatitis. He has also been hospitalized for 2 episodes of severe viral bronchiolitis. The mother reports that the infant has a good appetite but has had intermittent, non-bloody diarrhea. The patient is at the 20th percentile for weight. On physical examination, the patient has widespread, dry, erythematous patches, mucopurulent nasal drip, and crusting of the nares. His tongue is coated by a thick white film which is easily scraped off. Crackles are heard at the left lung base. Labs are drawn, as shown below:\n\nHemoglobin: 12.8 g/dL\nPlatelets: 280,000/mm^3\nLeukocytes: 7,500/mm^3\nNeutrophils: 5,500/mm^3\nLymphocytes: 2,000/mm^3\n\nSerum:\nNa+: 138 mEq/L\nCl-: 96 mEq/L\nK+: 4.3 mEq/L\nHCO3-: 23 mEq/L\nUrea nitrogen: 18 mg/dL\nGlucose: 90 mg/dL\nCreatinine: 1.0 mg/dL\nCa2+: : 9.2 mg/dL\n\nWhich of the following is the most likely cause of this patient’s presentation?", "answer": "Adenosine deaminase deficiency", "options": {"A": "22q11.2 deletion", "B": "Adenosine deaminase deficiency", "C": "Defective leukocyte adhesion", "D": "Defective tyrosine kinase", "E": "WAS gene mutation"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 51-year-old inmate was released from prison 1 month ago and visits his general practitioner for evaluation of a positive HIV diagnosis he received from a local free clinic a week ago. The patient states that he had spent the last 2 years in prison and that, during that time, he had engaged in multiple unprotected sexual acts with fellow male inmates. When he was released from prison recently, he decided to get tested for HIV and was diagnosed positive. He is currently married with 2 children and has been paroled back to the home he shares with them. He has not told either his wife or his children of his diagnosis. He adamantly states that he is not homosexual, but that his wife would assume that he is if she found out he had contracted HIV while in prison. He states that he is terrified his wife will leave him or possibly keep his children from seeing him if she finds out about his HIV status.  He wants to be treated without the threat of his wife finding out. He insists that he will use the proper precautions to ensure his wife and children don’t contract HIV from him and reiterates the importance of keeping his diagnosis a secret. He continues and states that “they are all I have. If they leave me, I have no one.” Which of the following is the most appropriate response in this patient’s case?", "answer": "Advise the patient the positive diagnosis will be reported to the public health office, but you would also encourage him to have a discussion with his family.", "options": {"A": "Honor the patient’s wishes and treat him without telling his wife or reporting him to the Department of Health", "B": "Tell the patient you will honor his wishes, but report him to the Department of Health so they can tell his wife", "C": "Obtain a court order to notify the patient’s wife", "D": "Consult an ethics committee to determine whether or not to report him to the Department of Health", "E": "Advise the patient the positive diagnosis will be reported to the public health office, but you would also encourage him to have a discussion with his family."}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 62-year-old man with end-stage renal disease is brought to the emergency department because of fever, severe abdominal pain, and shaking chills for 4 hours. His last hemodialysis was 2 days ago. On arrival, he appears ill and is poorly responsive. Blood cultures grow gram-positive, catalase-positive cocci that express mecA. Intravenous antibiotic therapy is begun with an agent that disrupts cell membranes by creating transmembrane channels. Which of the following adverse events is associated with the use of this agent?", "answer": "Rhabdomyolysis", "options": {"A": "Photosensitivity", "B": "Mucocutaneous necrosis", "C": "Rhabdomyolysis", "D": "Ototoxicity", "E": "QT prolongation"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 25-year-old woman comes to the physician because of pain and weakness in her left leg that started 2 days ago while running a marathon. Physical examination shows impaired flexion of the left knee joint and impaired extension of the left hip joint. An MRI of the left lower extremity shows injury to the long head of the biceps femoris muscle and the semitendinosus muscle. Which of the following is the most likely origin of the injured muscles?", "answer": "Ischial tuberosity", "options": {"A": "Superior pubic ramus", "B": "Ischial tuberosity", "C": "Anterior superior iliac spine", "D": "Greater trochanter", "E": "Linea aspera"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 32-year-old man and his 29-year-old wife come to the physician because they have been unable to conceive despite regular unprotected sexual intercourse for 13 months. The woman reports regular menstrual cycles since the age of 13. Menses occur at regular 28-day intervals and last 5–7 days. Ovulation predictor kits consistently turn positive around day 14. The man has a negative history of mumps. They each smoked one pack of cigarettes per day until one year ago. The man works in construction and his wife is a secretary for a law firm. Examination of the scrotum in a standing position shows soft bands palpated in the upper pole of the left scrotum with an intact left testicle. Following Valsalva maneuver, the patient reports a dull, aching pain in his left hemiscrotum. A light held behind the scrotum does not shine through. The right scrotum appears normal. Semen studies show normal sperm count with moderately decreased motility and abnormal morphology. Which of the following is most likely to improve the patient's ability to conceive?", "answer": "Ligation of dilated pampiniform venous plexus", "options": {"A": "Ligation of dilated pampiniform venous plexus", "B": "Orchidopexy", "C": "Conservative management with scrotal support", "D": "Surgical excision of the hydrocele sac", "E": "Administration of ceftriaxone and doxycycline"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 29-year-old man comes into his primary care physician's office with a chief complaint of a cough. The patient states that the cough started yesterday and he is asking if he needs antibiotics. While conversing with the patient, you note that he seems cold, mistrustful, and does not display much emotion. The patient worked for a software company but recently took a different position that allows him to work from home. The patient states that he switched positions because while at the office he made a mistake during a presentation. He felt that afterwards, his fellow workers thought less of him and he was embarrassed to show his face around the office. The patient wishes he could have related better to his coworkers. He currently lives in a barn on the outskirts of town with his many cats. On physical exam you note a healthy young man, adorned in overalls and denim shoes. His physical exam is notable for erythema of the posterior pharynx. The patient is informed that he has a viral upper respiratory infection and is sent home with instructions to rest and hydrate himself. Which of the following personality disorders best characterizes this patient?", "answer": "Avoidant", "options": {"A": "Avoidant", "B": "Schizoid", "C": "Schizotypal", "D": "Paranoid", "E": "Dependent"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 49-year-old man is undergoing an elective hernia repair. No significant past medical history or current medications. The patient has been working as a cardiovascular surgeon in the same hospital for the past 15 years. In obtaining informed consent, the patient’s doctor has described all the available options for the procedure with their pros and cons, has offered different materials for the hernioplasty, and described the exact procedure. He has not focused too much on the possible complications and the risks and benefits of not performing the operation, because the patient insists he already knows everything that can happen since he is a surgeon himself. The patient has given his consent, but on the day of the operation, he changes his mind regarding the material of the synthetic mesh to be used for the hernioplasty. Which of the following is true about informed consent in this case?", "answer": "The patient’s doctor should have included possible complications of the given operation and risks and benefits of not performing it, regardless of the patient’s education or prior experience.", "options": {"A": "The informed consent could be shortened to just the description of the available options for synthetic mesh because the patient is a medical specialist.", "B": "The informed consent obtained from this patient in this hospital is invalid because he works in the hospital.", "C": "There is no need to receive an informed consent from a patient who is a doctor himself.", "D": "The patient’s doctor should have included possible complications of the given operation and risks and benefits of not performing it, regardless of the patient’s education or prior experience.", "E": "Even though the patient has changed his mind about the type of mesh material, since the basic procedure is still the same, informed consent does not need to be obtained from the patient again."}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 55-year-old man presents to his primary care provider complaining of blood clots in his urine. On further questioning, he also reports suprapubic discomfort and a feeling of bladder fullness with difficulty voiding. The patient reports recently starting treatment for a newly diagnosed non-Hodgkin lymphoma. Vital signs are within normal limits. Physical exam reveals pain on palpation of the suprapubic region. What is the mechanism of action of the drug most likely responsible for the patient’s complaints?", "answer": "Alkylating agent", "options": {"A": "Alkylating agent", "B": "Intercalating agent", "C": "Reverse transcriptase inhibitor", "D": "Microtubule inhibitor", "E": "Folic acid analogue"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 25-year-old man presents to his primary care physician with lower back pain. He states that he has had the pain for the past two years. The patient works as a butcher, and recently was moving heavy meat carcasses. The patient states that his pain is worse in the morning and that nothing improves it aside from swimming. The patient has a past medical history of anabolic steroid abuse, acne, hypertension and obesity. His current medications are hydrochlorothiazide, ibuprofen, topical benzoyl peroxide, and acetaminophen. On physical exam there is no tenderness upon palpation of the spine. There is limited range of motion of the spine in all 4 directions. Which of the following is most likely to confirm the most likely diagnosis in this patient?", "answer": "MRI of the sacroiliac joint", "options": {"A": "Radiograph of the spine", "B": "MRI of the spine", "C": "The straight leg test and the clinical presentation", "D": "MRI of the sacroiliac joint", "E": "HLA typing"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 42-year-old African American female presents to your clinic complaining of excessive thirst and urination. She reports that these symptoms began one week ago, and they have been affecting her ability to work as a schoolteacher. Labs are drawn and are listed below.\n\nSerum:\nNa+: 145 mEq/L\nCl-: 101 mEq/L\nK+: 4.4 mEq/L\nHCO3-: 25 mEq/L\nUrea nitrogen: 24 mg/dL\nGlucose: 115 mg/dL\nCreatinine: 0.7 mg/dL\nHemoglobin: 10.5 g/dL\nHematocrit: 25%\nLeukocyte count: 11,000/mm^3\nPlatelets: 200,000/mm^3\n\nUrine:\nSpecific gravity: 1.006\nEpithelial cells: 5/hpf\nGlucose: negative\nProtein: 20 mg/dL\nRBC: 6/hpf\nWBC: 1/hpf\nLeukocyte esterase: negative\nNitrites: negative\nBacterial: none\n\nA water deprivation test is performed with the following results:\n\nSerum osmolality: 305 mOsm/kg\nUrine osmolality: 400 mOsm/kg\nUrine specific gravity: 1.007\n\nDesmopressin is administered, and the patient's urine osmolality increases to 490 mOsm/kg. The patient's antidiuretic hormone is measured and is within normal limits. Which of the following may be associated with this patient’s condition?", "answer": "Dactylitis", "options": {"A": "Coarse tremor", "B": "Auditory hallucinations", "C": "Amenorrhea", "D": "Peripheral neuropathy", "E": "Dactylitis"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 42-year-old male with a history of schizophrenia presents to his psychiatrist for a normal follow-up visit. He is accompanied by his case manager. The patient was diagnosed with schizophrenia at the age of 27. After being trialed on two different medications, he was deemed to be stable on a third medication which he has been taking for the past 10 years. He reports that he occasionally hears voices. He lives in supportive housing, and his caretakers report that he prefers to be alone but is not disruptive. His temperature is 99°F (37.2°C), blood pressure is 130/90 mmHg, pulse is 105/min, and respirations are 18/min. On exam, he demonstrates a flattened affect and disorganized speech. A funduscopic examination reveals pigmented plaques at the retinal periphery. No deposits are seen in the cornea or anterior lens. This patient has most likely been treated with which of the following medications?", "answer": "Thioridazine", "options": {"A": "Clozapine", "B": "Fluphenazine", "C": "Olanzapine", "D": "Chlorpromazine", "E": "Thioridazine"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 6-month-old girl is brought to the emergency department because her lips turned blue for several minutes earlier during feeding. Her father reports that the patient had similar episodes while playing that resolved quickly. During the examination, she sits calmly in her father's lap. When her ears are examined, the patient begins to cry and her lips and fingers begin to turn blue. Further evaluation of this patient is most likely to show which of the following?", "answer": "Right axis deviation on ECG", "options": {"A": "Machine-like hum on auscultation", "B": "Diminutive left ventricle on echocardiogram", "C": "Decreased blood pressure in both lower extremities", "D": "Pulmonary vascular congestion on chest x-ray", "E": "Right axis deviation on ECG"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 52-year-old female presents to clinic complaining of sudden onset of flank tenderness that was fluctuating and radiating into her groin. Laboratory analysis reveals a serum calcium of 12.4 (normal 8.4-10.2) and a serum phosphorous of 2.5 (normal 2.7-4.5) and a chloride:phosphorous ratio >33. You suspect primary hyperparathyroidism. Which of the following mechanisms is responsible for the patient’s current condition?", "answer": "Increased RANK-L production", "options": {"A": "PTH binding to receptors on osteoclasts", "B": "Parafollicular, or C-cell, synthesis of calcitonin", "C": "Increased RANK-L production", "D": "Decreased M-CSF production", "E": "Increased synthesis of osteoid by osteoblasts"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 53-year-old man comes to the physician because of a 2-week history of fatigue, generalized itching, and yellowing of the eyes and skin. He underwent a liver transplantation because of acute liver failure following α-amanitin poisoning 1 year ago. Physical examination shows scleral icterus and abdominal distention with shifting dullness. A liver biopsy specimen shows decreased hepatic duct density. Further histological examination of the liver biopsy specimen is most likely to show which of the following findings?", "answer": "Interstitial fibrosis", "options": {"A": "Graft vessel vasculitis", "B": "Neoplastic cells containing bile", "C": "Fibrinoid necrosis", "D": "Interstitial fibrosis", "E": "Viral inclusions\n\""}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 23-year-old man comes to the emergency department because of a 5-day history of progressively worsening dyspnea. He has had intermittent episodes of chest pain, which was 4/10 in intensity and increased on inspiration. He does triathlons and has not been able to train because of the discomfort. He has had no fever or syncopal episodes. He had an upper respiratory tract infection 3 weeks ago. His father died of heart disease at the age of 55 years. His temperature is 36.8°C (98.2°F), pulse is 113/min, and blood pressure is 100/70 mm Hg. Examination shows jugular venous distention. Inspiratory crackles are heard throughout the thorax. Cardiac examination shows an S3 gallop. Laboratory studies show:\nHemoglobin 14.8 g/dL\nLeukocyte count 9200/mm3\nPlatelet count 230,000/mm3\nESR 41 mm/hr\nSerum\nCreatinine 1.1 mg/dL\nGlucose 92 mg/dL\nLDH 120 U/L\nTroponin I 0.204 ng/mL (N< 0.1 ng/mL)\nAn x-ray of the chest shows an enlarged cardiac silhouette and prominent vascular markings in both lung fields. An ECG shows diffuse T-wave inversions. Which of the following echocardiographic findings is most likely in this patient?\"", "answer": "Left ventricular dilation and global hypokinesis", "options": {"A": "Swinging heart with compression of the left heart chambers", "B": "Increased left ventricular wall thickness", "C": "Mitral valve stenosis with left atrial enlargement", "D": "Left ventricular dilation and global hypokinesis", "E": "Vegetations on the mitral valve"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "Two days after undergoing abdominal surgery for lysis of adhesions, a 52-year-old man has nausea and one episode of bilious vomiting. The patient's nausea is somewhat alleviated in the prone position. The patient has had a 70-kg (154-lb) weight loss since undergoing bariatric surgery 1 year ago. Physical examination shows abdominal distention. Sudden movement of the patient elicits a sloshing sound on auscultation of the abdomen. An upper gastrointestinal series of the abdomen with oral contrast shows no passage of contrast past the third segment of the duodenum. The obstruction in this patient is most likely caused by which of the following structures?", "answer": "Superior mesenteric artery", "options": {"A": "Superior mesenteric artery", "B": "Gallbladder", "C": "Common bile duct", "D": "Portal vein", "E": "Inferior vena cava"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 16-year-old girl is brought to the physician because her mother is concerned about her lack of appetite and poor weight gain. She has had a 7-kg (15-lb) weight loss over the past 3 months. The patient states that she should try to lose more weight because she does not want to be overweight anymore. She maintains a diary of her daily calorie intake. Menarche was at the age of 13 years, and her last menstrual period was 3 months ago. She is on the high school track team. She is sexually active with 2 male partners and uses condoms inconsistently. She is at 50th percentile for height and below the 5th percentile for weight and BMI. Her temperature is 37°C (98.6°F), pulse is 58/min and blood pressure is 96/60 mm Hg. Examination shows fine hair over the trunk and extremities. Which of the following is the most likely diagnosis?", "answer": "Anorexia nervosa", "options": {"A": "HIV infection", "B": "Type 1 diabetes mellitus", "C": "Hyperthyroidism", "D": "Obsessive compulsive disorder", "E": "Anorexia nervosa"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 25-year-old male presents with progressively worsening headaches over the past two months. He also feels that he has been losing his balance more often over the past week, but he denies any motor weakness or sensory impairment. His neurological exam reveals impaired upward gaze, pupils that constrict poorly to light but react to accommodation, and bilateral upper eyelid retraction. On tandem walking, he tends to fall on both sides. The remainder of the physical examination is unremarkable. What is the most likely diagnosis in this patient?", "answer": "Pineal tumor", "options": {"A": "Frontal lobe tumor", "B": "Multiple sclerosis", "C": "Pituitary mass", "D": "Pineal tumor", "E": "Craniopharyngioma"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 32-year-old woman presents to an urgent care facility after having sustained a deep cut 8 hours ago while hiking in the Appalachian mountains. Immediately after she sustained the injury she rinsed out the dirt with a bottle of saline from her first aid kit. She immigrated to the United States at age 20 and was unvaccinated upon arrival. Her medical records indicate that she has since received one dose of Tdap and one Td booster 3 years ago. She is afebrile, well appearing, and her wound appears clean without signs of infection at this time. What is the next best step in management?", "answer": "Tetanus toxoid and tetanus immunoglobulin", "options": {"A": "Tetanus immunoglobulin only", "B": "Tetanus titers and if negative, tetanus toxoid and immunoglobulin within 48 hours", "C": "Tetanus toxoid only", "D": "Tetanus toxoid and tetanus immunoglobulin", "E": "Tetanus toxoid and tetanus immunoglobulin today; tetanus toxoid again on days 3, 7, and 14 after exposure"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 39-year-old woman presents to the emergency department with a chief concern of abdominal pain. She states that her symptoms occurred shortly after she began eating dinner that evening. She states that the pain is in the right side of her abdomen and travels to her right shoulder. She has a past medical history of polycystic ovarian syndrome, obesity, type II diabetes mellitus, and hypertension. Her current medications include metformin, insulin, atorvastatin, aspirin, and lisinopril. Her temperature is 99.5°F (37.5°C), blood pressure is 110/75 mmHg, pulse is 90/min, respirations are 13/min, and oxygen saturation is 99% on room air. On abdominal exam, the patient demonstrates tenderness in the right upper quadrant. The patient is started on IV fluids and morphine. Four hours later, she states that the pain has abated. Which of the following is associated with this patient's most likely diagnosis?", "answer": "Cholecystokinin", "options": {"A": "Acetylcholine", "B": "Cholecystokinin", "C": "Gastrin", "D": "Histamine", "E": "Secretin"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 12-year-old girl is brought to the primary physician because of severe ear pain and yellow discharge from her left ear for the past 2 days. It is also mildly pruritic. The pain started during her last day of summer camp, where she spent a lot of time outdoors hiking, horseback riding, and swimming. Her temperature is 37°C (98.6°F), pulse is 76/min, and blood pressure is 110/75 mm Hg. Examination shows tragal tenderness and a red and edematous external auditory canal. A diagnostic tuning fork is placed in the middle of the patient's forehead. The patient reports hearing the sound more loudly in the left ear. To complete the workup, the tuning fork is placed on the mastoid process of the left ear. Once she can no longer hear the sound, the tuning fork is placed in front of the auricle, and she reports no longer hearing the sound. On the right side, once the sound from the mastoid process subsides and the tuning fork is placed in front of the right ear, she reports hearing the sound again. Which of the following is the most likely cause of the patient's symptoms?", "answer": "Infection with Pseudomonas aeruginosa", "options": {"A": "Infection with Aspergillus species", "B": "Infection with varicella-zoster virus", "C": "Abnormal squamous epithelial growth", "D": "Infection with Pseudomonas aeruginosa", "E": "Pleomorphic replacement of normal bone\n\""}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 50-year-old man comes to the emergency department because of severe lower chest pain for the past hour. The pain radiates to the back and is associated with nausea. He has had two episodes of non-bloody vomiting since the pain started. He has a history of hypertension and type 2 diabetes mellitus. He has smoked one pack of cigarettes daily for 30 years. He drinks five to six beers per day. His medications include enalapril and metformin. His temperature is 38.5°C (101.3°F), pulse is 110/min, and blood pressure is 90/60 mm Hg. The lungs are clear to auscultation. Examination shows a distended abdomen with epigastric tenderness and guarding but no rebound; bowel sounds are decreased. Laboratory studies show:\nHemoglobin 14.5 g/dL\nLeukocyte count 5,100/mm3\nPlatelet count 280,000/mm3\nSerum\nNa+ 133 mEq/L\nK+ 3.5 mEq/L\nCl- 98 mEq/L\nTotal bilirubin 1.0 mg/dL\nAmylase 160 U/L\nLipase 880 U/L (N = 14–280)\nAn ECG shows sinus tachycardia. Which of the following is the most likely diagnosis?\"", "answer": "Acute pancreatitis", "options": {"A": "Acute mesenteric ischemia", "B": "Aortic dissection", "C": "Peptic ulcer disease", "D": "Myocardial infarction", "E": "Acute pancreatitis"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 29-year-old woman presents to the physician’s office complaining of swollen hands for the past 3 weeks. It is associated with stiffness in the morning, which lasts about 10 minutes. The patient’s medical history is significant for hypothyroidism that is managed with levothyroxine. She has no recent travel history. Vital signs are normal. On examination, the patient has a butterfly-shaped, non-blanching rash on her face with mild cervical lymphadenopathy. The metacarpophalangeal and proximal interphalangeal joints are tender and appear swollen. Cardiopulmonary examination reveals a grade 2/6 holosystolic murmur heard best at the apex. Which of the following tests is the best next step in evaluating this patient?", "answer": "Antinuclear antibody", "options": {"A": "Anti-double-stranded-DNA antibody", "B": "Anti-U1 ribonucleoprotein antibody", "C": "Lupus anticoagulant", "D": "Antinuclear antibody", "E": "Anti-histone antibody"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 61-year-old male dies in a motor vehicle accident. Autopsy of the heart reveals dilatation of the left atrium and expansion of the left ventricular cavity with associated eccentric hypertrophy. The structural changes in this patient's heart are most likely associated with which of the following?", "answer": "Mitral insufficiency", "options": {"A": "Pulmonic stenosis", "B": "Mitral insufficiency", "C": "Chronic hypertension", "D": "Wolff-Parkinson-White syndrome", "E": "Congenital atrial septal defect"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 52-year-old business executive presents to his physician with complaints of intermittent chest pain which started 2 months ago. He describes his pain as crushing, centrally located, and typically lasting about 5 minutes but never more than 10 minutes. The pain radiates to his left arm and jaw, occurs only when he climbs the stairs or runs on a treadmill, and is relieved by rest. He has been hypertensive and diabetic for the last 10 years and has been compliant with his medications. His physical exam findings are within normal limits. Lab tests are normal except for a significantly elevated LDL-cholesterol level. A stress ECG shows ST-segment depression in the anterior chest leads when his heart rate and blood pressure increase to over 40% from their baseline values. The physician decides to initiate a medication to relieve his symptoms. Which of the following changes best describes the direct effect of the prescribed medication on his cardiovascular physiology in the cardiac output/venous return versus right atrial pressure graph?", "answer": "iv", "options": {"A": "i", "B": "ii", "C": "iii", "D": "iv", "E": "vi"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 34-year-old man comes to the physician for a follow-up appointment. He was diagnosed with HIV 6 years ago and has been on highly active antiretroviral therapy with emtricitabine, tenofovir, and darunavir. He reports that he has been compliant with his medication regimen. His last CD4+ T-lymphocyte count was 520/mm3 (N > 500) and HIV viral load was undetectable. Today, his CD4+ T-lymphocyte count is 410/mm3 and his HIV viral load is 240 copies/mL. Further evaluation shows resistance to emtricitabine and tenofovir. Mutations in which of the following genes are most likely responsible for these findings?", "answer": "pol", "options": {"A": "tat", "B": "pol", "C": "rev", "D": "gag", "E": "env"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 61-year-old woman with a history of stage IV pancreatic cancer comes to the emergency department with insomnia due to intractable midepigastric pain. The pain had been constant for months but has worsened over the past few weeks despite the fact that she is already taking hydrocodone 10 mg and ibuprofen 400 mg. She has a past medical history of chronic pain and major depressive disorder. In the past month, she has been taking her pain medications with increasing frequency, going from twice a day to four times a day. Her other medications include venlafaxine and eszopiclone. She describes her mood as low, but states she does not have any suicidal thoughts. She appears fatigued and slightly cachectic. Her temperature is 36°C (96.8°F), pulse is 100/min, and blood pressure is 128/65 mm Hg. Physical examination shows a mass in the midepigastric region. Which of the following is the most appropriate next step in management?", "answer": "Switch from hydrocodone to hydromorphone", "options": {"A": "Discontinue hydrocodone and ibuprofen, and start IV ketorolac", "B": "Switch from hydrocodone to hydromorphone", "C": "Administer regional block of the celiac plexus using lidocaine", "D": "Switch from eszopiclone to zolpidem", "E": "Allow the patient to take hydrocodone and ibuprofen up to every four hours\n\""}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "Two days into hospitalization for pyelonephritis and sepsis, a 48-year-old woman develops severe sudden-onset dyspnea. She has no history of serious cardiopulmonary disease. She is fatigued and pale. Her blood pressure is 115/65 mm Hg, the pulse is 120/min, the respiratory rate is 36/min, and the temperature is 39.7°C (103.5°F). Her oxygen saturation is 80% on 60% FiO2. She has severe nasal flaring, supraclavicular and intercostal respiratory retractions, and paradoxical abdominal movements. Inspiratory crackles are heard over both lung fields. Cardiac examination shows no murmurs. A chest X-ray, taken before orotracheal intubation, is shown. Which of the following is the most appropriate next step in management?", "answer": "Low tidal volume ventilation", "options": {"A": "Broad-spectrum antibiotics", "B": "High-dose glucocorticoids", "C": "High positive end-expiratory pressure", "D": "Intravenous fluids", "E": "Low tidal volume ventilation"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 48-year-old man presents to the physician with a cough with expectoration and breathlessness on exertion for the last 4 years. There is no history of any other medical conditions. He has been a smoker for the last 10 years. He recently immigrated from a developing country and his immunization status is unknown. After a complete physical examination of the patient, the physician orders a chest radiogram which shows increased bronchovascular markings and flattening of the diaphragm. His spirometry findings include an FEV1 of 82% of predicted, which increases to 88% of predicted at 15 minutes after the administration of inhaled albuterol. The FEV1/FVC ratio is 0.66. The physician explains the diagnosis to the patient and emphasizes the importance of smoking cessation. He also offers him specific vaccinations. However, the patient mentions that he does not have medical insurance and due to his poor financial situation, he can afford only 1 of the suggested vaccines. In such a situation, which of the following vaccines should definitely be recommended to this patient?", "answer": "Influenza vaccine", "options": {"A": "13-valent pneumococcal conjugate vaccine", "B": "23-valent pneumococcal polysaccharide vaccine", "C": "Haemophilus influenzae type b vaccine", "D": "Influenza vaccine", "E": "Pertussis vaccine"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A five-year-old female presents to the pediatrician for a well visit. The patient’s parents report that she recently entered kindergarten and her teacher expressed concern that the patient is not meeting developmental milestones. She struggles to name colors and has not expressed any interest in learning to read. The patient’s parents have also noticed that the patient is not completing tasks that her older siblings were doing by this age, including dressing herself independently and going to the bathroom by herself. The patient rolled over at 9 months, sat without support at 12 months, and walked at 20 months. Her parents also report that the patient is very social, and that adults frequently comment on her friendly personality. The patient is in the 15th percentile for weight and 5th percentile for height. On physical exam, the patient has a broad forehead, flat nasal bridge, long philtrum, and a wide mouth. She has a strabismus on neurological exam, and her cardiac exam is significant for a heart murmur. Laboratory testing is below:\n\nSerum:\nNa+: 145 mEq/L\nK+: 3.9 mEq/L\nCl-: 100 mEq/L\nHCO3-: 24 mEq/\nUrea nitrogen: 11 mg/dL\nGlucose: 76 mg/dL\nCreatinine: 0.9 mg/dL\nCa2+: 11.9 mg/dL\n\nWhich of the following cardiac abnormalities is associated with this condition?", "answer": "Supravalvular aortic stenosis", "options": {"A": "Bicuspid aortic valve", "B": "Coarctation of the aorta", "C": "Complete atrioventricular septal defect", "D": "Supravalvular aortic stenosis", "E": "Tetralogy of Fallot"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 20-year-old male comes to the physician because of a 1-week-history of a painless ulceration on his penis. The patient is sexually active with multiple partners and does not use barrier protection. Physical examination shows a shallow, firm ulcer with a smooth base along the shaft of the penis and nontender bilateral inguinal adenopathy. Which of the following is most likely to confirm the diagnosis in this patient?", "answer": "Dark field microscopy", "options": {"A": "Tzanck preparation", "B": "Culture swab", "C": "Urine polymerase chain reaction", "D": "Dark field microscopy", "E": "Serologic detection of antibodies"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 31-year-old man presents to the clinic as a follow-up visit after recently being diagnosed with medullary thyroid cancer. Last year, he was diagnosed with a pheochromocytoma that was successfully resected. His family history is positive for medullary thyroid cancer in his father and paternal grandmother with a mucosal neuroma in his brother. What additional finding is most likely to be present in this patient on physical examination?", "answer": "Marfanoid habitus", "options": {"A": "Ash leaf spot", "B": "Hyperparathyroidism", "C": "Pituitary adenoma", "D": "Neurofibromas", "E": "Marfanoid habitus"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "Digestion begins in the mouth by breaking food up into smaller particles through mastication and mixing it with saliva containing amylase. Food then enters the stomach, where gastric acid and pepsin initiate protein digestion. The resulting chyme is then expelled into the duodenum where pancreatic enzymes, such as lipase and phospholipase-A2, digest lipids. These digested lipids are then ready for absorption across the gastrointestinal mucosa. Resection of which of the following segments of the gastrointestinal tract would prevent the absorption of these digested lipids?", "answer": "Jejunum", "options": {"A": "Jejunum", "B": "Ileum", "C": "Ascending colon", "D": "Descending colon", "E": "Rectum"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A group of investigators is studying hemodynamic regulatory mechanisms in a human volunteer subject. The volunteer is administered a stimulant drug, and a sudden increase in blood pressure is observed. It is hypothesized that the increase in blood pressure causes stretching of the atria. Increased atrial stretch would most likely lead to which of the following changes?", "answer": "Decreased reabsorption of sodium", "options": {"A": "Increased excretion of potassium and hydrogen ions", "B": "Vasodilation and decreased platelet aggregation", "C": "Decreased reabsorption of sodium", "D": "Increased reabsorption of solute-free water", "E": "Vasoconstriction and stimulation of thirst"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 26-month-old boy is presented to the outpatient clinic by his parents complaining of a productive cough for the last 5 days. His mother reports a history of recurrent chest infections during the past year. He also has a history of chronic bloody diarrhea and pronounced bleeding after his circumcision. The vital signs are as follows: blood pressure 100/60 mm Hg, pulse 100/min, temperature 38.0°C (100.4°F), and respiratory rate 27/min. On examination, there are purpuric eruptions over the extremities as well as eczematous patches on the flexural surfaces of his elbows and knees. Chest auscultation reveals crepitus over the base of the right lung. Chest radiography is suggestive of consolidation in the right lower lobe. Blood test results show anemia, thrombocytopenia with small platelets, and leukopenia. With a suspicion of a congenital immunodeficiency, flow cytometry is ordered which reveals a Wiskott-Aldrich syndrome protein (WASP) mutation. Which of the following would be the definitive treatment of this patient’s condition?", "answer": "Early hematopoietic stem cell transplantation (HSCT)", "options": {"A": "Early hematopoietic stem cell transplantation (HSCT)", "B": "Intravenous immunoglobulin (IVIG)", "C": "Rituximab", "D": "Chemotherapy", "E": "Corticosteroids"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "Four hours after undergoing an open emergency surgery under general anesthesia for a bleeding abdominal aortic aneurysm, a 55-year-old man is unable to move both his legs. During the surgery, he had prolonged hypotension, which was corrected with IV fluids and vasopressors. He has a history of hypertension and hyperlipidemia. He has smoked one pack of cigarettes daily for 35 years. Prior to admission, his medications were hydrochlorothiazide and atorvastatin. The patient is conscious and oriented to place and person. His temperature is 37.7°C (99°F), pulse is 74/min, and blood pressure is 100/70 mm Hg. Examination shows muscle strength of 1/5 in the lower extremities. Further evaluation of this patient is most likely to show which of the following?", "answer": "Normal proprioception in the extremities\n\"", "options": {"A": "Normal temperature sensation in the extremities", "B": "Babinski's sign present bilaterally", "C": "Normal bulbocavernosus reflex", "D": "Bilaterally increased knee and ankle jerk", "E": "Normal proprioception in the extremities\n\""}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 30-year-old woman seeks evaluation at a local walk-in clinic with a week-long history of lightheadedness and palpitations. She also complains of fatigability and shortness of breath of the same duration. The past medical history is significant for menarche at 9 years of age, heavy menstrual bleeding for the past several years and abdominal pain that worsens during menses. She stopped trying to conceive a child after 2 spontaneous abortions in the past 4 years and has been on iron oral supplementation for the last 2 years. She adds that she feels a dull pressure-like discomfort in her pelvis and constipation. The physical examination is significant for pale mucous membranes and a grade 2/6 ejection systolic murmur in the area of the pulmonic valve. Pelvic examination reveals an enlarged, mobile uterus with an irregular contour. The hemoglobin level is 10 g/dL and the hematocrit is 27%. Based on these findings, which of the following is the most likely diagnosis?", "answer": "Uterine leiomyoma", "options": {"A": "Uterine adenomyosis", "B": "Uterine leiomyoma", "C": "Endometrial hyperplasia", "D": "Endometrial carcinoma", "E": "Endometrial polyp"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A study is conducted in a town with a population of 225,000, where the people are followed-up for the development of emphysema. A total of 1,000 smokers are selected and followed-up, out of which 200 actually develop the disease. A control group of 1,000 non-smokers is formed, out of which 20 develop emphysema. The prevalence of smoking in the general population is 40%. The researcher calculates all possible risk estimates, including the odds ratio. What percentage of the risk of developing emphysema can be attributed to smoking?", "answer": "18%", "options": {"A": "40%", "B": "20%", "C": "10%", "D": "2%", "E": "18%"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A medical student is performing clinical research by analyzing the aggregated data of all patients from a national database. In performing the study, she uses all the data collected from patients who had an appendectomy and analyzes the risk factors that are associated with readmission after discharge. She first excludes some of the data based on previously determined exclusion criteria and then performs analysis on the rest. She performs a multiple regression on all variables and finds that one of the risk factors demonstrates a < 5% probability of being the same between groups. She takes this result and presents it to faculty; however, they respond that the finding is meaningless. Which of the following faults to this study most likely explains why the result was considered meaningless?", "answer": "Failure to consider clinical significance versus statistical significance", "options": {"A": "Data should not be excluded from the analysis", "B": "Data should not have been aggregated", "C": "Failure to consider clinical significance versus statistical significance", "D": "Single rather than multiple regression should have been performed", "E": "Usage of the wrong threshold for significance"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 60-year-old man presents to the emergency department with ‘discomfort’ in his chest and a ‘squeezing’ sensation in his neck. The symptoms started 45 minutes ago while he was washing the dishes. He also complains of nausea. He has been a regular smoker for 45 years, averaging a pack of cigarettes each day. He also drinks heavily on weekends. His medical history is significant for a stroke 3 months ago, but the patient admits he has not been taking his medications. Vital signs show: pulse 62/min, respiratory rate 20/min, blood pressure 176/94 mm Hg, and temperature 36.9°C (98.4°F). Physical examination reveals a visibly distressed man who is sweating profusely. The chest is clear to auscultation and a 4th heart sound can be heard. Aspirin was administered upon arrival. His ECG is shown in the picture. Which of the following features is a contraindication for thrombolytic therapy in this patient?", "answer": "Stroke 3 months ago", "options": {"A": "Patient's age", "B": "Aspirin administration", "C": "Elevated blood pressure", "D": "History of smoking", "E": "Stroke 3 months ago"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 3-year-old girl is brought by her parents to the office for bloody diarrhea and a seizure. The parents say she started having fever, abdominal pain, and diarrhea about 3 days ago, but the bloody diarrhea started 12 hours ago. The seizure was the last symptom to appear 3 hours ago, and it consisted of repetitive movement of arms and legs with loss of consciousness. Her 4-year-old brother had a similar case with bloody diarrhea 2 weeks ago. Her vital signs include: blood pressure is 130/85 mm Hg, her respiratory rate is 25/min, her heart rate is 120/min, and her temperature is 39.2°C (102.6°F). On physical examination, she looks pale and sleepy, the cardiopulmonary auscultation is normal, the abdomen is painful on palpation, and the skin assessment reveals the presence of disseminated pinpoint petechiae. The urinalysis show hematuria. The Coombs test is negative. The complete blood count results are as follows:\nHemoglobin 7 g/dL\nHematocrit 25 %\nLeukocyte count 17,000/mm3\nNeutrophils 70%\nBands 2%\nEosinophils 1%\nBasophils 0%\nLymphocytes 22%\nMonocytes 5%\nPlatelet count 7,000/mm3\nHer coagulation tests are as follows:\nPartial thromboplastin time (activated) 30 seconds\nProthrombin time 12 seconds\nReticulocyte count 1 %\nThrombin time < 2 seconds deviation from control\nWhat is the most likely diagnosis?", "answer": "Hemolytic-uremic syndrome", "options": {"A": "Disseminated intravascular coagulation", "B": "Henoch-Schonlein purpura", "C": "Salmonella infection", "D": "Systemic vasculitis", "E": "Hemolytic-uremic syndrome"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 68-year-old woman presents to the emergency room with productive cough and fever. She has a chronic cough that has been getting progressively worse over the last 2 weeks. Last night she developed a fever and vomited. She smoked one pack of cigarettes per day for 40 years and recently quit. Her past medical history includes COPD and her medications include ipratropium and fluticasone. On physical exam her temperature is 102.2°F (39°C), blood pressure is 131/78 mmHg, pulse is 110/min, respirations are 22/min, and oxygen saturation is 95% on room air. She has decreased breath sounds bilaterally with diffuse crackles. You obtain a sputum sample and identify an organism that grows selectively on medium containing factors V and X. Which of the following organisms is the most likely cause of this patient's symptoms?", "answer": "Haemophilus influenzae", "options": {"A": "Haemophilus influenzae", "B": "Streptococcus pneumoniae", "C": "Bacteroides species", "D": "Mycoplasma pneumoniae", "E": "Fusobacterium species"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 36-year-old man comes to the physician because of progressive fatigue and night sweats for 2 months. During this time, he has also had a 10-kg (22-lb) weight loss. Physical examination shows painless swelling of the cervical, axillary, and inguinal lymph nodes. Examination of the abdomen shows hepatosplenomegaly. Histologic examination of a lymph node biopsy specimen shows Reed-Sternberg cells. A diagnosis of Hodgkin lymphoma is made. The patient is started on a chemotherapeutic regimen that includes bleomycin. The mechanism of action of this drug is most similar to that of which of the following?", "answer": "Metronidazole", "options": {"A": "Trimethoprim", "B": "Sulfamethoxazole", "C": "Rifampin", "D": "Metronidazole", "E": "Chloramphenicol"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "An 7-year-old girl is brought to the pediatrician by her concerned mother, because she is \"more physically matured\" than the rest of the girls in her class. On physical exam, she is noted to have breast development and pubic hair. On gonadotropin reseasing hormone (GnRH) stimulation, she has an increase in leutienizing hormone (LH) levels. Thyroid function tests and an MRI of the head are both within normal limits. Which of the following is the most appropriate treatment for this condition?", "answer": "Leuprolide", "options": {"A": "Ketoconazole", "B": "Leuprolide", "C": "Finasteride", "D": "Octreotide", "E": "Anastrozole"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 45-year-old woman presents to the emergency department with hematemesis. Her son said that the patient had complained of gnawing abdominal pain that worsened before and improved after meals for the past 3 weeks. She frequently travels for work and is often stressed. She drinks alcohol socially and does not smoke tobacco or marijuana. She has not had anything to eat or drink for the past 24 hours due to the pain, but coughed up \"several cup of\" frank red blood before arrival. Her temperature is 98°F (37°C), blood pressure is 80/50 mmHg, pulse is 140/min, respirations are 23/min, and oxygen saturation is 96% on room air. Gastric ultrasound reveals high gastric residual volume. The patient is empirically started on 3 units of uncrossmatched O-negative blood transfusion and pantoprazole. The patient's initial laboratory data return in the meantime:\n\nHemoglobin: 5 g/dL\nHematocrit: 18 %\nLeukocyte count: 8,000/mm^3 with normal differential\nPlatelet count: 400,000/mm^3\n\nSerum:\nNa+: 140 mEq/L\nCl-: 115 mEq/L\nK+: 3.2 mEq/L\nHCO3-: 26 mEq/L\nBUN: 60 mg/dL\nGlucose: 104 mg/dL\nCreatinine: 1.1 mg/dL\n\nBlood type: AB\nRhesus status: negative\n\nAfter bedside esophageogastroduodenoscopy with stapling of several peptic ulcers, repeat labs are obtained in 2 hours. The patient now complains of feeling hot with intermittent shivering. She denies any other symptoms. Her temperature is 101°F (38.3°C), blood pressure is 100/55 mmHg, pulse is 100/min, respirations are 20/min, and oxygen saturation is 99% on room air. Her lungs are clear to auscultation bilaterally, and no accessory respiratory muscle use is observed. No rash is seen. What is the most likely diagnosis?", "answer": "Febrile nonhemolytic reaction", "options": {"A": "Citrate toxicity", "B": "Febrile hemolytic reaction", "C": "Febrile nonhemolytic reaction", "D": "Transfusion related bacterial contamination", "E": "Transfusion related acute lung injury"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 66-year-old man comes to the physician because of a 3-week history of shortness of breath with exertion. He has hypertension, hyperlipidemia, and type 2 diabetes mellitus. Current medications include aspirin, losartan, simvastatin, and insulin. His temperature is 37.1°C (98.8°F), pulse is 74/min, and blood pressure is 150/84 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 96%. Cardiac examination is shown. Further evaluation of this patient is most likely to show which of the following?", "answer": "Elevated serum brain natriuretic peptide levels", "options": {"A": "Earlier onset of abnormal cardiac sound with standing", "B": "Elevated serum brain natriuretic peptide levels", "C": "Digital clubbing", "D": "Left-to-right shunt through the atrial septum", "E": "Bounding pulses of peripheral arteries"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 27-year-old gravida 2, para 2 woman presents to her OB/GYN’s office concerned that she may be pregnant. She and her husband use condoms for contraception. The night before, the condom broke during intercourse. She has 2 children under the age of 3 and does not want another child at this time. She says she cannot take “the pill” because she had a blood clot in her leg after her last cesarean section successfully treated with 6 months of anticoagulation. She smokes cigarettes and drinks alcohol regularly. Which of the following would be the most appropriate recommendation for this patient?", "answer": "Recommend copper IUD", "options": {"A": "Reassure her that she is likely not pregnant", "B": "Refer her to an abortion clinic", "C": "Recommend etonogestrel implant", "D": "Recommend copper IUD", "E": "Recommend levonorgestrel IUD"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 25-year-old Ashkenazi Jewish man presents to his primary care physician for a follow-up visit. One week ago, he presented with a chief complaint of priapism while engaging in intercourse with two of his partners. During that visit, it was determined that his blood pressure was 175/100 mmHg. He returns this week to have his vitals rechecked. His temperature is 99.5°F (37.5°C), pulse is 80/min, blood pressure is 182/100 mmHg, respirations are 10/min, and oxygen saturation is 98% on room air. Bloodwork is drawn and is shown below.\n\nSerum:\nNa+: 139 mEq/L\nK+: 3.7 mEq/L\nCl-: 100 mEq/L\nHCO3-: 28 mEq/L\nUrea nitrogen: 9 mg/dL\nGlucose: 122 mg/dL\nCreatinine: 1.0 mg/dL\nCa2+: 9.8 mg/dL\nMg2+: 1.7 mg/dL\n\nAfter a physical exam is performed, which of the following is the best initial step in management for this patient's underlying condition?", "answer": "Duplex ultrasound", "options": {"A": "Begin lifestyle modification and weight loss program", "B": "Begin lifestyle modification, weight loss program, and hydrochlorothiazide", "C": "24-hour urinary cortisol", "D": "Duplex ultrasound", "E": "Serum aldosterone level"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 63-year-old man is brought to the emergency department after having 8–9 episodes of red watery stool. He has no abdominal pain or fever. He underwent an angioplasty 4 years ago and received 2 stents in his left main coronary artery. He has hypertension, hypercholesterolemia, coronary artery disease, and chronic constipation. Current medications include aspirin, metoprolol, and simvastatin. He drinks one beer daily. He is in distress. His temperature is 37.3°C (99.1°F), pulse is 110/min, respirations are 14/min, and blood pressure is 86/58 mm Hg. Examination shows pale conjunctivae. The abdomen is soft and nontender. Bowel sounds are increased. The lungs are clear to auscultation. Cardiac examination shows an S4 gallop. Rectal examination shows frank blood. Laboratory studies show:\nHemoglobin 9.8 g/dL\nLeukocyte count 7,800/mm3\nPlatelet count 280,000/mm3\nProthrombin time 14 seconds (INR=0.9)\nSerum\nNa+ 135 mEq/L\nK+ 4.1 mEq/L\nCl- 101 mEq/L\nUrea nitrogen 16 mg/dL\nGlucose 96 mg/dL\nCreatinine 0.7 mg/dL\nTwo large bore intravenous catheters are inserted and 0.9% saline infusions are administered. A nasogastric tube is inserted. Aspiration shows clear gastric content containing bile. Directly afterwards, his pulse is 133/min and blood pressure is 80/54 mm Hg. Which of the following is the most appropriate next step in management?\"", "answer": "Angiography", "options": {"A": "Angiography", "B": "Laparotomy", "C": "Colonoscopy", "D": "Esophagogastroduodenoscopy", "E": "Enteroscopy"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 15-month-old boy with Down syndrome is brought to the physician for a well-child examination. The mother is concerned about giving the child any more vaccinations, as she reports he had a fever of 38.7°C (101.7°F) soon after his vaccinations at 12-months of age. He has had a runny nose for 2 days. He has a seizure disorder with a seizure lasting 1–2 minutes a few times a week that has not been controlled by medications. He was treated for intussusception at 6 months of age. His father was diagnosed with HIV 2 years ago. His medications include phenytoin, levetiracetam, and vitamin supplements. He is allergic to amoxicillin and has previously developed localized urticaria after consumption of eggs. His immunizations are up-to-date. Vital signs are within normal limits. Examination shows low-set ears, hypertelorism, and a flat head. The remainder of the examination shows no abnormalities. Which of the following is a relative contraindication for administering one or more routine vaccinations in this patient at this time?", "answer": "Uncontrolled seizure disorder\n\"", "options": {"A": "Egg protein allergy", "B": "Fever of 38.7°C (101.7°F) after previous vaccination", "C": "Current upper respiratory tract infection", "D": "History of intussusception", "E": "Uncontrolled seizure disorder\n\""}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 1-year-old boy is brought to his pediatrician’s office due to regression of development. She has observed that he is not progressing as he did during the 1st year of his life. There seems to be a regression in some behavioral and other milestones. She is also concerned about his facial development. On examination, the vital signs are normal. He has coarse facial features with a bulging frontal bone. Additionally, his lips are enlarged and corneal clouding is observed. Urine studies show an increase in dermatan sulfate. Which of the following genetic conditions is most likely related to these clinical features?", "answer": "Hurler syndrome", "options": {"A": "Hunter syndrome", "B": "Morquio syndrome", "C": "Tay-Sachs disease", "D": "Hurler syndrome", "E": "Fabry disease"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 6-year-old African American girl is brought to the physician by her mother because she has recently developed axillary and pubic hair. She also has multiple pustules on her forehead and has had oily skin for 3 months. Her mother reports that she recently bought some deodorant for the girl because of her body odor. Her mother has hypothyroidism. She is at the 95th percentile for height and the 99th percentile for weight and BMI. Her vital signs are within normal limits. She has no palpable glandular breast tissue. There is coarse hair under both axilla and sparse dark hair on the mons pubis and along the labia majora. Which of the following is the most likely explanation for this patient's examination findings?", "answer": "High levels of insulin", "options": {"A": "High levels of insulin", "B": "Adrenal enzyme deficiency", "C": "Overproduction of leptin", "D": "Pituitary tumor", "E": "Ovarian cyst"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 45-year-old woman comes to the physician for a health maintenance examination. Her father has a history of type 2 diabetes mellitus. She has gained 18-kg (40-lb) since the birth of her son 6 years ago. Her BMI is 31 kg/m2. Physical examination shows hyperpigmented plaques in the axillae and posterior neck. Laboratory studies show a hemoglobin A1c of 6.4% and an elevated serum insulin level. Which of the following factors is most likely involved in the pathogenesis of this patient's condition?", "answer": "Increased levels of serum fatty acids", "options": {"A": "Increased serum levels of glucagon-like peptide-1", "B": "Positive MHC class I serotype", "C": "Increased levels of serum fatty acids", "D": "Decreased levels of serum cortisol", "E": "Positive HLA-DR4 serotype"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "An 89-year-old woman presents with worsening dyspnea on exertion and generalized fatigue. She has fainted once. Exam reveals a crescendo-decrescendo systolic ejection murmur that radiates to the carotids. What pathological step preceded calcification in her condition?", "answer": "Cellular injury and necrosis", "options": {"A": "Commissural fibrosis", "B": "Congenital bicuspid valve", "C": "Fibrillin-1 deficiency", "D": "Cellular injury and necrosis", "E": "Cellular hypertrophy"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 22-year-old man presents to the emergency department for chest pain. He says that the chest pain began a few hours prior to presentation and is associated with nausea, abdominal discomfort, and sweating. He has experienced similar symptoms multiple times in the past, which brings him great concern because he believes he may be having a heart attack. This concern has persisted for 2 months. This has caused him to avoid taking long train rides or driving on divided highways. Approximately 7 months ago his parents divorced. Medical history is significant for obesity. He denies any medications or illicit drug use. Physical examination is unremarkable. An electrocardiogram demonstrates sinus tachycardia with a pulse of 110/min. Which of the following is most likely the diagnosis?", "answer": "Panic disorder", "options": {"A": "Adjustment disorder", "B": "Illness anxiety disorder", "C": "Panic disorder", "D": "Somatic symptom disorder", "E": "Specific phobia"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "An investigator is developing a new vaccine. Eukaryote ribosomes are utilized to create a novel protein. After the aminoacyl-tRNA binds to the A site, which of the following is the next step in protein formation?", "answer": "Catalysis of peptide bond", "options": {"A": "Catalysis of peptide bond", "B": "Recognition of UAG codon by release factor", "C": "Assembly of 40s subunit with tRNA", "D": "Advancement of ribosome in 3' direction", "E": "Assembly of 60S subunit with mRNA"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 70-year-old Caucasian woman presents with a 2-week history of blood-tinged sputum. Her past medical history is significant for peptic ulcer disease for which she underwent triple-drug therapy. She is a lifetime non-smoker and worked as a teacher before retiring at the age of 60 years. A review of systems is significant for a weight loss of 6.8 kg (15 lb) over the last 5 months. Her vitals include: blood pressure 135/85 mm Hg, temperature 37.7°C (99.9°F), pulse 95/min, and respiratory rate 18/min. Physical examination is unremarkable. A contrast CT scan of the chest shows an irregular mass in the peripheral region of the inferior lobe of the right lung. A CT-guided biopsy is performed and reveals malignant tissue architecture and gland formation with a significant amount of mucus. Which of the following is the most significant risk factor for this patient’s most likely diagnosis?", "answer": "Sex", "options": {"A": "Medications", "B": "Occupational history", "C": "Past medical history", "D": "Race", "E": "Sex"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "Four days after admission to the hospital for community-acquired pneumonia, a 68-year-old woman has abdominal pain and multiple episodes of loose stools. They are watery, foul-smelling, and occasionally streaked with blood. She has approximately 6 episodes daily. She feels tired. She is currently being treated with intravenous ceftriaxone and oral azithromycin. She underwent a laparoscopic cholecystectomy 5 years ago. She returned from a trip to Bolivia 4 weeks ago. Her temperature is 37.5°C (99.5°F), pulse is 98/min, and blood pressure is 138/80 mm Hg. Bronchial breath sounds are heard over her right lung. Abdominal examination shows mild diffuse tenderness throughout the lower quadrants. The abdomen is not distended. The remainder of her examination shows no abnormalities. Her hemoglobin concentration is 12 g/dL, leukocyte count is 14,100/mm3, and erythrocyte sedimentation rate is 37 mm/h. Which of the following is the most appropriate next step in management?", "answer": "Enzyme immunoassay for glutamate dehydrogenase antigen", "options": {"A": "Stool for ova and parasites", "B": "Fecal lactoferrin", "C": "Enzyme immunoassay for glutamate dehydrogenase antigen", "D": "Stool acidity test", "E": "Sigmoidoscopy"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "An otherwise healthy 52-year-old man comes to the physician because of a 2-month history of palpitations. He says that he can feel his heart beat in his chest all the time. For the past 3 weeks, he has shortness of breath on exertion. He has not had chest pain, orthopnea, or nocturnal dyspnea. He emigrated from Nepal at the age of 25 years. He does not take any medications. His temperature is 36.5°C (97.7°F), pulse is 103/min, and blood pressure is 138/56 mm Hg. The lungs are clear to auscultation. Cardiac examination is shown. Which of the following is the most likely diagnosis?", "answer": "Aortic valve regurgitation", "options": {"A": "Pulmonary valve stenosis", "B": "Aortic valve regurgitation", "C": "Tricuspid valve regurgitation", "D": "Pulmonary valve regurgitation", "E": "Mitral valve prolapse"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 55-year-old male presents to the emergency department after he was seen having a seizure. On presentation he is comatose and very jaundiced despite having no previous medical history and dies shortly thereafter. Over the next several hours 5 more patients present to the ER with severe diarrhea, abdominal pain, and bleeding abnormalities. They all recently returned from a several day camping trip where they slept in the woods and cooked with ingredients they were able to find in the wild. The original patient was also part of this camping trip. Postmortem analysis reveals massive hepatic necrosis. Which of the following activities was most likely inhibited by the cause of this patient's presentation?", "answer": "Transcription of mRNA", "options": {"A": "Splicing of mRNA", "B": "Transcription of mRNA", "C": "Transcription of rRNA", "D": "Transcription of tRNA", "E": "Translation of mRNA"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 46-year-old woman is brought to the emergency department for respiratory depression. Routine urine toxicology screening is positive for alcohol, fentanyl, and benzodiazepines. Blood glucose is 80 mg/dL. Naloxone, flumazenil, and lactated Ringer's solution are administered intravenously. Two hours later, the woman has a tonic-clonic seizure lasting for one minute. Her pulse is 100/min, blood pressure is 145/90 mm Hg, and respiratory rate is 24/min. Pulse oximetry on room air shows an oxygen saturation of 98%. The patient appears drowsy and diaphoretic. She is not oriented to place or time but responds to her name. Examination shows a hematoma on her left temple. Neurological examination shows stiff extremities and a tremor in both hands. The remainder of the examination shows no abnormalities. Which of the following is the most likely cause of this patient's seizure?", "answer": "Benzodiazepine withdrawal", "options": {"A": "Hypoglycemia", "B": "Benzodiazepine withdrawal", "C": "Alcohol withdrawal", "D": "Fentanyl overdose", "E": "Subdural hemorrhage"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 22-year-old man comes to the emergency department because of sudden onset of facial swelling, abdominal pain, and nausea 1 hour after eating some trail mix. He does not have shortness of breath or hoarseness. He has never had a similar episode before. He has asthma treated with an albuterol inhaler, which he uses less than once a month. His pulse is 90/min, respirations are 25/min, and blood pressure is 125/80 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 99%. Physical examination shows perioral swelling and scattered urticaria over the face and the fingers of his right hand. There is no swelling of the oropharynx and no audible stridor. The lungs are clear to auscultation bilaterally. Treatment with intravenous diphenhydramine is begun. Shortly after, the abdominal pain and nausea have resolved, the swelling has improved, and the rash has started to fade. Which of the following is the most appropriate next step in management?", "answer": "Prescribe epinephrine autoinjector", "options": {"A": "Recommend avoidance of peanuts", "B": "Perform patch test", "C": "Prescribe epinephrine autoinjector", "D": "Advise to carry oral cetirizine at all times", "E": "Administer oral prednisone"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 2-year-old boy is referred by his primary care physician to a geneticist because of prolonged and recurrent infections. Specifically, he has had an abnormally large number of upper respiratory and gastrointestinal infections over the last year. He was born with a defect in the cardiac septum that was repaired right after birth and has remained asymptomatic since then. On evaluation, the patient appears to have hyperactive reflexes and his arm twitches upon blood pressure measurement. The regions of this patient's lymph nodes that is likely abnormal also contains which of the following?", "answer": "High endothelial venules", "options": {"A": "Efferent sinuses", "B": "High endothelial venules", "C": "Plasma cell cords", "D": "Primary follicles", "E": "Subcapsular macrophages"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 45-year-old woman presents with a 2-year history of fatigue, paresthesia, diarrhea, and abdominal pain. She says she experiences 2–3 episodes of non-bloody diarrhea per month associated with crampy abdominal pain. She also has the bilateral tingling sensation of her upper and lower limbs in a glove and stocking pattern which is sometimes associated with the burning sensation of her hands and legs. Past medical history is unremarkable. The patient denies smoking, alcohol consumption, illicit drug use. Her vital signs include: blood pressure 100/60 mm Hg without postural changes, heart rate 92/min, respiratory rate 16/min, temperature 37.0℃ (98.6℉). Laboratory findings are significant for the following:\nHgb 7.2 gm/dL\nMCV 110 fL\nRBC 3.6 X109/L\nPlatelets 10,000/mm3\nTotal count  4,200/mm3\nReticulocyte 0.8%\nA peripheral blood smear demonstrates hypersegmented neutrophils. Anti-intrinsic factor and anti-tissue transglutaminase antibodies were negative. An upper GI series with small bowel follow-through is performed which shows a narrowing of the barium contrast in the lumen of the terminal ileum to the width of a string. Which of the following is the most likely diagnosis in this patient?", "answer": "Crohn's disease", "options": {"A": "Pernicious anemia", "B": "Celiac disease", "C": "Crohn's disease", "D": "Bacterial overgrowth", "E": "Hypothyroidism"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 15-month-old boy is brought to his pediatrician by his mother with a swollen and painful right elbow. She reports that he stumbled and fell on the carpeted floor of their living room, hitting his right elbow on the ground. The mother reports that he did not appear to be in a great deal of pain after the fall, and that she noted the swelling of the joint a few hours after the fall. He recently started walking approximately 2 weeks ago. He does not have any known medical issues, and he is not currently on medication. The mother's pregnancy was without complications and the boy was delivered vaginally without complications at 40 weeks. Aspiration of the right elbow joint reveals frank blood. Which of the following should be included in the work-up of this patient?", "answer": "Prothrombin time/partial thromboplastin time", "options": {"A": "Peripheral blood smear", "B": "Creatinine level and percutaneous kidney biopsy", "C": "Prothrombin time/partial thromboplastin time", "D": "24 hour urine collection for porphyrin levels", "E": "Rheumatoid factor"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 45-year-old male comes into your office one week after he was tackled playing football with his friends. The patient states that the medial aspect of his knee collided with another player's knee. Since then, he has been taking ibuprofen for knee pain. On exam, the patient's right knee appears larger than his left knee with a small effusion. The patient has intact sensation and strength in both lower extremities. The patient's right knee has no laxity on valgus stress test, but is very lax on varus stress test. Lachman's test and posterior drawer test both have firm endpoints without laxity. McMurray's test is positive and the patient states he feels catching and locking during the test. Which of the following structures has this patient injured in addition to the meniscus?", "answer": "Lateral collateral ligament", "options": {"A": "Anterior cruciate ligament", "B": "Posterior cruciate ligament", "C": "Medial collateral ligament", "D": "Lateral collateral ligament", "E": "Medial patellofemoral ligament"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 19-month-old girl is brought for a well-child examination. She was born at term and has been healthy. On physical examination, the child is alert and active. Her temperature is 37.3 °C (99.1 °F), pulse is 102/min, respirations are 24/min, and blood pressure is 102/54 mm Hg. She is at the 75th percentile for height and 80th percentile for weight. Cardiac examination shows a normal S1 and a split S2 during inspiration. A grade 2/6 soft mid-systolic murmur is heard maximally at the lower left sternal border. A contrast echocardiogram is performed and reveals a mild transient right-to-left interatrial shunt that becomes apparent when the child coughs. Which of the following is the most appropriate next step in management?", "answer": "No intervention", "options": {"A": "No intervention", "B": "Warfarin therapy", "C": "Aspirin therapy", "D": "Surgical closure", "E": "Regular echocardiographies"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 6-year-old girl is brought to the emergency department because of right knee pain for the past 3 days. During this period, the girl has refused to walk. Her mother reports that her symptoms began after she fell down while playing. Three weeks ago, the patient had a sore throat and was treated with penicillin V. Her father has hemophilia A and has had repeated episodes of joint pain and swelling following minor injury. The patient's immunizations are up-to-date. Her temperature is 38.1°C (100.6°F), pulse is 120/min, and respirations are 21/min. The right knee joint is warm and erythematous. The girl starts to cry as soon as the physician tries to flex the knee joint. Further evaluation of this patient is likely to show which of the following findings?", "answer": "Gram-positive cocci in synovial fluid", "options": {"A": "Positive antinuclear antibody test", "B": "Gram-positive cocci in synovial fluid", "C": "Prolonged prothrombin time", "D": "Increased antistreptolysin O titers", "E": "Rhomboid crystals in synovial fluid"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 35-year-old man attempted to climb Mount Everest. At an altitude of 7,000 meters, he became short of breath and developed a dusky blue tinge around his face and lips. A physician in the climbing party performs a rudimentary physical exam which reveals a respiratory rate of 30/min, blood pressure of 130/90 mm Hg, heart rate of 108/min, and temperature of 36.4°C (97.5°F), with few basal crackles on the right side of chest. No jugular venous distension or dependent edema is noted. With this information, the mountain climber is sent down the mountain for further evaluation. Investigation reveals a normal chest X-ray with a normal heart size. What is the most likely cause of this patient’s condition?", "answer": "Hypoxemic hypoxia", "options": {"A": "Diffusion defect", "B": "Anemic hypoxia", "C": "Ischemic hypoxia", "D": "Hypoxemic hypoxia", "E": "Methemoglobinemia"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 28-year-old man who was involved in a motorcycle accident presents to the nearest trauma center to get his wounds treated. After the initial evaluation and resuscitation by the emergency trauma team, a CT scan shows a skull base fracture. Which of the following clinical features can be seen as a long-term complication of posterior pituitary dysfunction?", "answer": "Polydipsia", "options": {"A": "Erectile dysfunction", "B": "Decreased lean body mass", "C": "Hyponatremia", "D": "Polydipsia", "E": "Cold intolerance"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 19-year-old woman comes to the physician for a follow-up examination. She has a history of type 1 diabetes mellitus and is compliant with her medications. After reviewing the patient's recent blood sugar levels, the physician changes the patient's antidiabetic regimen by changing the dosage of an insulin that does not produce an observable peak in serum insulin concentration. The dosage of which of the following types of insulin was most likely changed in this patient's medication regimen?", "answer": "Insulin glargine", "options": {"A": "Insulin glargine", "B": "Insulin glulisine", "C": "Regular insulin", "D": "Insulin lispro", "E": "NPH insulin"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 31-year-old woman visits her local walk-in clinic for 2 days of dysuria, increased voiding frequency, urgency, and intense suprapubic pain. She just came back a day ago from a short honeymoon trip to Prague. On physical examination, the patient is found with exquisite suprapubic pain. Costovertebral tenderness is absent and pelvic examination is normal. Her vital signs are: temperature 36.5°C (97.7°F), heart rate 78/min, respiratory rate 15/min. Which of the following organisms would be most likely isolated in this patient?", "answer": "Staphylococcus saprophyticus", "options": {"A": "Streptococcus agalactiae", "B": "Enterococcus faecalis", "C": "Proteus mirabilis", "D": "Klebsiella pneumoniae", "E": "Staphylococcus saprophyticus"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 14-year-old boy is brought to the physician by his mother because of a 1-week history of fever, fatigue, and throat pain. He appears lethargic. His temperature is 38.5°C (101.3°F). Physical examination shows bilateral cervical lymphadenopathy. Oral examination shows the findings in the photograph. A peripheral blood smear shows lymphocytosis with atypical lymphocytes. A heterophile antibody test is positive. Which of the following is the most appropriate recommendation by the physician?", "answer": "Avoid contact sports", "options": {"A": "Start oral amoxicillin therapy", "B": "Start antiretroviral therapy", "C": "Schedule bone marrow biopsy", "D": "Avoid contact sports", "E": "Avoid crowded places"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 62-year-old carpenter presents to your clinic complaining of worsening joint pain in her hands. She states that the pain is present in all of her fingers, but is worse in the right hand and that it gets better when she has a few days off from work. She notes no paresthesias, fever, or fatigue. On examination, the patient is afebrile and all vital signs are stable. She has hard, non-tender lesions overlying the proximal interphalangeal joints of the 2nd and 3rd fingers on the right hand and all 5 digits on this hand have a decreased range of motion. An X-ray of her hands is shown. What is the most likely pathogenesis leading to the X-ray findings?", "answer": "Repetitive movement injury", "options": {"A": "Repetitive movement injury", "B": "Overgrowth of a gram-positive bacteria", "C": "Deposition of monosodium urate crystals", "D": "Genetic predisposition associated with the HLA-B27 gene", "E": "Production of rheumatoid factor and other autoantibodies"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 7-year-old girl presents to the emergency department with a bloody nose that spontaneously started bleeding 20 minutes ago. On physical examination, she appears well and has no lymphadenopathy. Her heart has a regular rate and rhythm, her lungs are clear to auscultation bilaterally, and her abdomen is soft without hepatosplenomegaly, but she does have petechiae over her lower extremities. A complete blood count is obtained and reveals a leukocyte count of 11,300 cells/mcL, hemoglobin 12.1 g/dL, hematocrit 36%, and platelets 15,000/mcL. A peripheral smear shows a few morphologically normal platelets. Her mother reports that she had a viral infection 2 weeks ago but has been otherwise healthy. Which of the following is the next best step?", "answer": "Start intravenous immunoglobulin", "options": {"A": "Start intravenous immunoglobulin", "B": "Give 1 unit of packed erythrocytes", "C": "Perform a splenectomy", "D": "Perform a bone marrow aspiration", "E": "Observation"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 2-year-old boy is brought to the physician by his parents because their son frequently avoids eye contact and has no friends in daycare. He was born at term and has been healthy except for an episode of otitis media 6 months ago. His immunizations are up-to-date. He is at the 95th percentile for height, 20th percentile for weight, and 95th percentile for head circumference. Vital signs are within normal limits. Examination shows elongated facial features and large ears. The patient is shy and does not speak or follow instructions. He continually opens and closes his mother's purse and does not maintain eye contact. Which of the following is the most likely cause of this patient's presentation?", "answer": "CGG trinucleotide repeat expansion on X-chromosome", "options": {"A": "CGG trinucleotide repeat expansion on X-chromosome", "B": "Deletion of the long arm on chromosome 7", "C": "Genomic imprinting on chromosome 15", "D": "Trisomy", "E": "An additional X chromosome"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 78-year-old man is admitted to hospital for treatment of a severe attack of pneumonia he has been experiencing for the past three days. A week earlier, he had been feeling well until he developed what he describes as a mild cold. Over the next few days, he began to have difficulty breathing and developed a productive cough and fever. As his condition worsened despite antibiotic therapy at home, he was admitted for intravenous antibiotics and observation. He has a 50-pack-year history of smoking and has been diagnosed with chronic obstructive pulmonary disease (COPD). Prior to admission, the man was taking inhaled formoterol, budesonide, and oxygen at home. He has been drinking 3 alcoholic drinks daily for the last 60 years and smoked marijuana during his 20s. His lab results from 1 week ago and from his day of admission to hospital are as follows:\n7 days ago\nOn admission to hospital\nSerum glucose (random)  130 mg/dL\nSerum electrolytes\nSodium 142 mEq/L\nPotassium 3.9 mEq/L\nChloride 101 mEq/L\nSerum creatinine 0.8 mg/dL\nBlood urea nitrogen 9 mg/dL\nCholesterol, total 170 mg/dL\nHDL-cholesterol 42 mg/dL\nLDL-cholesterol 110 mg/dL\nTriglycerides 130 mg/dL\nSerum glucose (random)  100 mg/dL\nSerum electrolytes\nSodium 140 mEq/L\nPotassium 4.0 mEq/L\nChloride 100 mEq/L\nSerum creatinine 0.9 mg/dL\nBlood urea nitrogen 11 mg/dL\nCholesterol, total 130 mg/dL\nHDL-cholesterol 30 mg/dL\nLDL-cholesterol 80 mg/dL\nTriglycerides 180 mg/dL\nWhat best explains the change in this patient’s lipid profile over this time period?", "answer": "Physiological response", "options": {"A": "COPD exacerbation", "B": "Drug side effect", "C": "Physiological response", "D": "Pneumonia complication", "E": "Undiagnosed dyslipidemia"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 42-year-old woman comes to the physician because of a 4-week history of progressive difficulty swallowing solid foods. The patient reports feeling like food gets stuck in her throat, and that she has to drink a lot of water to swallow her meals. Over the past 3 months, she has had progressive fatigue and occasional dyspnea while performing her daily activities. Her pulse is 104/min, respirations are 19/min, and blood pressure is 110/70 mm Hg. Physical examination shows conjunctival pallor, erythema around the corners of the mouth, and dry, scaly lips. Her fingernails appear spoon-shaped and brittle. Auscultation of the heart shows a grade 1/6 systolic murmur best heard at the second left intercostal space. Esophagogastroduodenoscopy shows thin membranes that are protruding into the upper third of the esophagus. Further evaluation of the patient is most likely to show which of the following?", "answer": "Craving for non-nutritive substances", "options": {"A": "Altered sense of smell", "B": "Intolerance to cold temperatures", "C": "Thickening of the skin", "D": "Eosinophilic infiltration of the esophagus", "E": "Craving for non-nutritive substances"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 27-year-old nullipara makes an appointment with her gynecologist to discuss the results of her cervical cancer screening. She is not vaccinated against HPV and has a single sexual partner. She and her partner are planning pregnancy, so she recently discontinued oral contraception and began to take folate and iron supplements. She has no history of gynecologic diseases. Her first Pap smear showed atypical squamous cells of undetermined significance, but 2 subsequent Pap smears had normal results. The most recent Pap smear was reported as a high-grade squamous intraepithelial lesion. Colposcopy was performed at the next visit and a biopsy was obtained from a small patch of the acetowhite epithelium at the cervical transformation zone. The pathologic assessment shows CIN 3. Which of the following statements regarding the management of this patient is correct?", "answer": "Close follow-up with cytology and colposcopy may be considered in this patient.", "options": {"A": "Observation of young patients with CIN 3 is preferred because of a high chance of regression.", "B": "The annual rate of progression of CIN 3 to cancer is > 10%, so the patient should be treated as soon as possible.", "C": "Close follow-up with cytology and colposcopy may be considered in this patient.", "D": "Additional HPV testing would be useful to guide the therapy.", "E": "Pregnancy is not recommended in women with high-grade cervical lesions, so treatment is reasonable."}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 47-year-old woman comes to the physician because of a 3-month history of recurrent episodes of nausea and feeling like the room is spinning. Each episode lasts less than a minute and usually occurs when she gets out of bed in the morning or suddenly turns her head. She has not vomited and does not have headaches. She is asymptomatic between episodes. Which of the following findings most closely correlates with this patient's symptoms?", "answer": "Nystagmus", "options": {"A": "Intention tremor", "B": "Nystagmus", "C": "Binocular diplopia", "D": "Abnormal Rinne test", "E": "Orthostatic hypotension"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 56-year-old man is brought to the emergency department by his wife because of increasing confusion and lethargy for the past 12 hours. He is oriented only to person. His temperature is 37.3°C (99.1°F), pulse is 109/min, respirations are 18/min, and blood pressure is 108/67 mm Hg. Examination shows abdominal distention and several erythematous, lacy lesions on the chest that blanch with pressure. His hands make a flapping motion when they are dorsiflexed. Which of the following is the most likely precipitating factor for this patient's symptoms?", "answer": "Presence of hemoglobin in the intestine", "options": {"A": "Elevated systemic vascular resistance", "B": "Destruction of gut anaerobes", "C": "Thiamine pyrophosphate deficiency", "D": "Presence of hemoglobin in the intestine", "E": "Low protein consumption"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 63-year-old man comes to the physician because of a 4-hour history of severe pain in the right knee. His temperature is 38.0°C (100.1°F). Examination shows erythema, edema, and warmth of the right knee; range of motion is limited by pain. Arthrocentesis of the knee joint yields cloudy fluid with a leukocyte count of 24,000/mm3 (74% segmented neutrophils). Polarized light microscopy shows needle-shaped, negatively birefringent crystals. Five hours after treatment with a drug is begun, he develops abdominal cramp, diarrhea, and vomiting. The patient was most likely treated with a drug that predominantly acts on which of the following parts of the cell?", "answer": "Cytoskeleton", "options": {"A": "Cell wall", "B": "Cytosolic enzyme", "C": "Nucleus", "D": "Cytoskeleton", "E": "Membrane transporter"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 1-year-old boy presents to the emergency department for several days of irritability and poor feeding. His parents are very concerned that he has been acting differently. The patient has an unremarkable past medical history and has been followed by a pediatrician. His temperature is 102°F (38.9°C), blood pressure is 57/38 mmHg, pulse is 170/min, respirations are 35/min, and oxygen saturation is 99% on room air. During the exam the infant is irritable and is crying. Musculoskeletal exam reveals that the patient's knee can not be extended while the patient's hip is in a flexed position without significant patient irritation. Fundoscopy is within normal limits. Abdominal, cardiac, and pulmonary exam are within normal limits. Which of the following is the next best step in management?", "answer": "Lumbar puncture", "options": {"A": "Blood and urine cultures", "B": "Head CT", "C": "Lumbar puncture", "D": "Vancomycin and ceftriaxone", "E": "Vancomycin, ceftriaxone, and prednisone"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 74-year-old man comes to the physician because of a 2-month history of shortness of breath and leg swelling. He has trouble climbing one flight of stairs due to dyspnea. He has hypertension and was diagnosed with multiple myeloma 6 months ago. Current medications include hydrochlorothiazide. Cardiopulmonary examination shows jugular venous distention, bibasilar crackles, and pitting edema in the lower extremities. Transthoracic echocardiography shows a thickened myocardium with elevated diastolic filling pressures. Which of the following is the most likely underlying mechanism of this patient's cardiomyopathy?", "answer": "Amyloid deposition", "options": {"A": "Chronic vasoconstriction", "B": "Myosin gene mutation", "C": "Amyloid deposition", "D": "Chronic hypercalcemia", "E": "Iron deposition"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 47-year-old man is brought to the emergency department 30 minutes after he was involved in a motor vehicle collision. On arrival, he is unconscious and unresponsive to painful stimuli. His pulse is 120/min, respirations are 10/min, and his blood pressure is 88/60 mm Hg. Infusion of 0.9% saline is begun, and intubation is attempted without success. Pulse oximetry on 20 L/min of oxygen via bag mask shows an oxygen saturation of 78%. The next appropriate step in the management of this patient involves passing a tube through an incision through which of the following structures?", "answer": "Investing layer of deep cervical fascia", "options": {"A": "Investing layer of deep cervical fascia", "B": "Annular ligament", "C": "Cricotracheal ligament", "D": "Prevertebral layer of deep cervical fascia", "E": "Thyrohyoid ligament"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "Parents bring an 11-month-old baby to the clinic because the baby has a fever of 39.0°C (102.2°F). The baby is irritated and crying constantly. She is up to date on immunizations. A complete physical examination reveals no significant findings, and all laboratory tests are negative. Five days after resolution of her fever, she develops a transient maculopapular rash. What is the most likely diagnosis?", "answer": "Roseola", "options": {"A": "Roseola", "B": "Erythema infectiosum", "C": "Rubella", "D": "Measles", "E": "Kawasaki disease"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 67-year-old man is brought to his primary care practitioner by his daughter who has noticed a ‘pill-rolling’ tremor in his right hand, along with a progressively slow, shuffling gait. The patient’s daughter says that these symptoms gradually started 2 weeks ago and have progressively worsened. His past medical history is significant for hypertension, which is well-controlled with losartan. He does not take any other medications. Physical examination reveals a slow shuffling gait, difficulty initiating movements, a resting tremor in his right hand that decreases in intensity with voluntary movement, and cogwheel-like rigidity in the right arm. The primary care practitioner decides to prescribe levodopa and carbidopa. Which of the following statements would best explain the mechanism of action of these drugs?", "answer": "Increased dopamine synthesis", "options": {"A": "Inhibition of the enzyme monoamine oxidase (MAO) B", "B": "Stimulation of dopamine receptors", "C": "Blockade of muscarinic receptors", "D": "Inhibition of dopamine reuptake", "E": "Increased dopamine synthesis"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 79-year-old man with a long-standing history of hypertension and diabetes presents to the emergency department with sudden-onset of loss of motor function on the left side of his body. Neurologic exam shows normal sensation throughout the body. MRI of the brain is obtained and shows a small sub-cortical infarct involving a perforating vessel. Which of the following is the most likely underlying pathogenesis?", "answer": "Lipohyalinosis of small vessels", "options": {"A": "Embolism originating from the left atrium", "B": "Berry aneurysm", "C": "Lipohyalinosis of small vessels", "D": "Large vessel thrombosis", "E": "Fibromuscular dysplasia"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A cardiology specialist working in the university hospital center noticed that a large number of his patients who had myocardial infarctions also had some sort of malignancy in their medical history. In order to determine whether a relationship existed between myocardial infarction and malignant processes, he decided to pursue a case-control study. His selected cases consisted of a sample of patients hospitalized in an internal ward with a history of a myocardial infarction, while control cases were patients on the same ward without a history of a myocardial infarction. Their charts and medical documentation were then reviewed for a history of any type of malignancy. The results of the study led the cardiologist to conclude that, for patients with malignancy, the odds of having a myocardial infarction were 3.2 times higher when compared to patients without malignancy. If the cardiologist was aware of Berkson’s bias (also known as the admission rate bias), he could minimize it by which of the following?", "answer": "Recruiting the controls from different wards to increase disease variability", "options": {"A": "Including the diagnoses negatively related to the risk factor being studied", "B": "Increasing the number of cases and controls included in the study", "C": "Excluding controls that present a probability of hospital admission similar to cases", "D": "Recruiting the controls from different wards to increase disease variability", "E": "Excluding those patients with preferential recollection of exposures"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 27-year-old woman presents to her primary care physician’s office with fatigue, headaches, and concentration difficulties. Her symptoms began approximately 7 months prior to presentation. Throughout this time, she reports problems with initiating and remaining asleep, has noticed periods of muscle soreness, and has feelings of restlessness. She states that she is very concerned about whether she will be able to pay her monthly expenses and if her parents are satisfied with her career choices. She is also worried about how her colleagues and supervisor think of her performance at work. She denies any significant past medical history besides occasional palpitations. She takes a daily multivitamin. Family history is significant for panic disorder in her mother. She currently lives alone and at times socializes with friends. She occasionally drinks alcohol during social gatherings, does not smoke, and denies any illicit drug use. Her temperature is 99°F (37.2 °C), blood pressure is 110/75, pulse is 101/min, and respirations are 18/min. Physical examination is unremarkable. Which of the following is the most appropriate pharmacologic treatment for this patient?", "answer": "Buspirone", "options": {"A": "Buspirone", "B": "Imipramine", "C": "Mirtazapine", "D": "Olanzapine", "E": "Trazodone"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 73-year-old man comes in to the emergency department because of nausea and severe pain in his upper abdomen and right shoulder blade for the past day. He was able to eat a little for breakfast but vomited up the meal a couple of hours later. He has type 2 diabetes mellitus treated with metformin. He has smoked half a pack of cigarettes daily for 40 years and drinks 4 beers every week. He appears acutely distressed. His temperature is 38.8°C (102°F), pulse is 124/min, and blood pressure is 92/68 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 95%. The abdomen is soft and there is tenderness to palpation of the right upper quadrant with soft crepitus. The remainder of the examination shows no abnormalities. Laboratory studies show:\nHemoglobin 14.3 g/dL\nLeukocyte count 18,100/mm3\nPlatelet count 216,000/mm3\nSerum\nAspartate aminotransferase (AST, SGOT) 41 U/L\nAlanine aminotransferase (ALT, SGPT) 19 U/L\nAlkaline phosphatase 110 U/L\nTotal bilirubin 0.9 mg/dL\nDirect bilirubin 0.2 mg/dL\nAlbumin 4.1 g/dL\nUltrasonography of the right upper quadrant shows a gallbladder with an air-filled, thickened wall and no stones in the lumen. Which of the following is the most likely diagnosis?\"", "answer": "Emphysematous cholecystitis", "options": {"A": "Chronic pancreatitis with pseudocyst rupture", "B": "Emphysematous cholecystitis", "C": "Gallstone ileus", "D": "Perforated duodenal ulcer", "E": "Primary sclerosing cholangitis"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 26-year-old man presented with a headache and fatigue for the past few months. On presentation to the clinic, the blood pressure is 190/110 mm Hg; the femoral pulse is reduced compared to the radial pulse, and an ejection click is heard. There was no murmur. Which of the following is associated with his condition?", "answer": "Coarctation of the aorta", "options": {"A": "Mitral valve regurgitation", "B": "Ventricular septal defect (VSD)", "C": "Wolff-Parkinson-White syndrome", "D": "Coarctation of the aorta", "E": "Atrial septal defect (ASD)"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 57-year-old man with a history of diabetes and stage 3 chronic kidney disease is admitted to the hospital for elective coronary angiography. The senior resident admitting the patient to the ward is concerned about his chronic renal impairment and the scheduled angiography, which will require the use of intravenous contrast. Which of the following strategies is most likely to decrease the likelihood that the procedure will exacerbate the patient’s renal failure?", "answer": "Use non-iodinated contrast medium", "options": {"A": "Intravenous mannitol before and during the procedure", "B": "Intravenous N-acetyl cysteine before and during the procedure", "C": "Hemodialysis immediately after the procedure", "D": "Use non-iodinated contrast medium", "E": "Forced diuresis with furosemide"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 17-year-old girl is brought in a wheelchair because of gradually progressive difficulty in walking, incoordination, and frequent falls. Her symptoms started at 9 years old with clumsiness while walking. She later experienced difficulties with coordination, which later involved her arms and trunk. She was born at term with normal developmental milestones. The physical examination reveals severely ataxic gait, nystagmus, absent deep tendon reflexes, and loss of vibration and proprioception. Presuming it is an inherited condition, what is the most likely genetic pathophysiology of this disorder?", "answer": "GAA trinucleotide repeats", "options": {"A": "Dystrophin gene mutation", "B": "GAA trinucleotide repeats", "C": "Mitochondrial DNA mutation", "D": "NOTCH3 mutation", "E": "PMP22 gene duplication"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A previously healthy 51-year-old man is brought to the emergency department because of confusion for 2 hours. His wife reports that he fell and hit his head while changing a ceiling light the previous evening. On arrival, he is unconscious. His temperature is 37.1°C (98.8°F), pulse is 54/min, respirations are 8/min and irregular, and blood pressure is 198/106 mm Hg. The right pupil is dilated and fixed; the left pupil is round and reactive to light. There is extension of the extremities to painful stimuli. He is intubated and mechanically ventilated. A mannitol infusion is begun. A noncontrast CT scan of the brain shows herniation of the right medial temporal lobe. Which of the following is the most likely additional finding in this patient?", "answer": "Right-sided hemiplegia", "options": {"A": "Right-sided hemiplegia", "B": "Left-side facial nerve palsy", "C": "Bilateral spasticity", "D": "Multifocal myoclonus", "E": "Right eye esotropia and elevation"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 1-year-old female presents to the emergency department with 2 days of fever up to 103ºF. During the course of her work-up, a urine culture reveals gram negative rods and a urinary tract infection (UTI) is diagnosed. She is placed on ceftriaxone and quickly defervesces. Follow-up of the urine culture reveals the causal bacteria was E. coli, without any concerning resistance patterns and was susceptible to ceftriaxone. This is her first UTI and there is no family history of renal abnormalities or vesicourethral reflux. In addition to her current therapy, what additional steps should be taken during the management of this child's UTI?", "answer": "Renal bladder ultrasound", "options": {"A": "Prophylactic antibiotic therapy to prevent future UTIs", "B": "Voiding cystourethrogram", "C": "Renal bladder ultrasound", "D": "Repeat urine culture", "E": "Renal scintigraphy"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 22-year-old woman presents to her primary care physician because she has been having severe pruritus on her left leg. She says the symptoms started 1 week ago after she went on a hiking trip with her friends. She wore shorts during the hike and felt as if something brushed her skin on the front of her leg just below the knee. She has no past medical history and no family history of autoimmune diseases. On physical exam, she has red pruritic papules and vesicles on her left leg. Which of the following mechanisms was most likely involved in the development of this patient's symptoms?", "answer": "Cytotoxicity due to T-cells", "options": {"A": "Activation of cell surface receptors by antibodies", "B": "Cross-linking of IgE antibodies", "C": "Cytotoxicity due to antibodies", "D": "Cytotoxicity due to T-cells", "E": "Immune complex deposition"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "An adopted 7-year-old boy is brought to a pediatrician with a history of progressive muscular weakness, intellectual impairment, and speech problems. The adoptive parents say that the patient was normal at birth, but as he grew older, his muscular weakness increased. Physical examination reveals the wasting of muscles of the dorsal forearm and the anterior compartment of the lower legs. Thenar and hypothenar eminences are also flattened. However, deep tendon reflexes are 2+ bilaterally. His face has an atypical appearance with thin cheeks and temporal wasting. When he was asked to make a tight fist and open his hands quickly, he could not open them immediately, and relaxation of the contracted muscles was very slow. The pediatrician suspects genetic muscular dystrophy. Which of the following is the trinucleotide repeat linked to this patient’s most likely condition?", "answer": "CTG", "options": {"A": "CTG", "B": "CAG", "C": "CGG", "D": "GAA", "E": "CGT"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 36-year-old woman presents to her primary care physician for her yearly physical exam. She says that she has been experiencing some mild shortness of breath, but otherwise has no medical complaints. Her past medical history is significant for allergies and asthma as a child, but she is not currently taking any medications or supplements. She does not smoke and drinks about 2 glasses of wine per week as a social activity. On physical exam she is asked to take deep breaths during cardiac auscultation. The physician notices that the splitting of S2 decreases during inspiration. Which of the following is most consistent with this physical exam finding?", "answer": "Left bundle branch block", "options": {"A": "Asthma recurrence", "B": "Atrial septal defect", "C": "Left bundle branch block", "D": "Pulmonary stenosis", "E": "Right bundle branch block"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 47-year-old woman presents to the emergency department with calf pain and swelling that has persisted for the past 24 hours. She recently had an elective cholecystectomy performed 3 days ago that was complicated intraoperatively by bleeding requiring a transfusion of 1 unit of packed red blood cells. The patient is otherwise healthy, and her vitals are within normal limits. Physical exam is notable for an enlarged and tender right calf. Ultrasound with doppler reveals non-compressible veins of the affected leg. Which of the following is appropriate initial management of this patient?", "answer": "Heparin", "options": {"A": "CT angiogram of the chest", "B": "Discharge and close outpatient follow up", "C": "Heparin", "D": "Inferior vena cava filter", "E": "Warfarin"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 24-year-old primigravida is admitted to the hospital at 36 weeks gestation with a headache and blurred vision. The vital signs are as follows: blood pressure, 170/95 mm Hg; heart rate, 88/min; respiratory rate, 15/min; and temperature, 36.6℃ (97.9℉). The physical examination is significant for pitting edema of the lower extremity. Meningeal signs are negative. The ophthalmoscopic exam shows vascular narrowing and a cotton-like fundal exudate. The dipstick test shows 1+ proteinuria. While the blood is being drawn, the patient has a generalized tonic-clonic seizure. Which of the following options describe the most likely mechanism underlying the patient’s seizure?", "answer": "Failure of cerebral vasoregulation", "options": {"A": "Increase in the extracellular sodium concentration", "B": "Failure of cerebral vasoregulation", "C": "Inhibition of brain GABA-signaling", "D": "Increased activation of NMDA receptors", "E": "Dysfunction of neuronal voltage-gated Ca-channels"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 12-month-old girl is brought in by her mother to the pediatrician for the first time since her 6-month checkup. The mother states that her daughter had been doing fine, but the parents are now concerned that their daughter is still not able to stand up or speak. On exam, the patient has a temperature of 98.5°F (36.9°C), pulse is 96/min, respirations are 20/min, and blood pressure is 100/80 mmHg. The child appears to have difficulty supporting herself while sitting. The patient has no other abnormal physical findings. She plays by herself and is making babbling noises but does not respond to her own name. She appears to have some purposeless motions. A previous clinic note documents typical development at her 6-month visit and mentioned that the patient was sitting unsupported at that time. Which of the following is the most likely diagnosis?", "answer": "Rett syndrome", "options": {"A": "Language disorder", "B": "Rett syndrome", "C": "Fragile X syndrome", "D": "Trisomy 21", "E": "Cerebral palsy"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 55-year-old man comes to the emergency department because of cramps and left-sided flank pain, nausea, and urinary frequency for 3 hours. He has no history of serious illness and takes no medications. He drinks 2–3 alcoholic beverages daily. His temperature is 37.2°C (99.0°F), pulse is 107/min, and blood pressure is 145/80 mm Hg. Examination of the back shows left costovertebral angle tenderness. An x-ray of the abdomen shows no abnormalities. Abdominal ultrasound shows a 4-mm stone in the distal left ureter and a scatter of small stones in the left renal pelvis. Urinalysis shows RBCs and needle-shaped crystals, but no WBCs. Pain medication and intravenous fluids are administered. In addition to adequate hydration, the patient is most likely to benefit from which of the following?", "answer": "Potassium citrate", "options": {"A": "Probenecid", "B": "Vitamin C", "C": "Potassium citrate", "D": "High-protein diet", "E": "Hydrochlorothiazide"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 4-year-old boy is brought to the physician because of a 1-month history of generalized fatigue. During the past week, he has also had fever and severe leg pain that keeps him awake at night. Examination shows cervical and axillary lymphadenopathy. His liver is palpated 4 cm below the right costal margin and the spleen is palpated 3 cm below the left costal margin. His hemoglobin concentration is 10.2 g/dL, leukocyte count is 64,500/mm3, and platelet count is 29,000/mm3. A bone marrow aspirate predominantly shows immature cells that stain positive for CD10, CD19, and TdT. Which of the following is the most likely diagnosis?", "answer": "Acute lymphoblastic leukemia", "options": {"A": "Leukemoid reaction", "B": "Idiopathic thrombocytopenic purpura", "C": "Acute myeloid leukemia", "D": "Acute lymphoblastic leukemia", "E": "Hodgkin lymphoma"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 41-year-old man comes to the physician because of a 10-day history of generalized weakness. He has also had headaches and night sweats and is a known user of illicit intravenous drugs. His temperature is 39.1°C (102.4°F), pulse is 110/min, respirations are 17/min, and blood pressure is 127/78 mm Hg. There are several track marks on his forearms. A holosystolic murmur that increases on inspiration is heard along the left sternal border. Laboratory studies show a leukocyte count of 13,900/mm3 and an erythrocyte sedimentation rate of 58 mm/h. Which of the following is the most likely consequence of this patient's condition?", "answer": "Pulmonary embolism", "options": {"A": "Hematuria", "B": "Rupture of nail-bed capillaries", "C": "Retinal hemorrhages", "D": "Pulmonary embolism", "E": "Painful nodules on pads of the fingers"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 17-year-old girl presents to the emergency department with a painful rash on her head. She says that she started noticing a rash 2 weeks ago that has gotten worse over time. In addition, she says that she has been very thirsty over the same time period and often needs to urgently use the restroom during the day, which has been disrupting her ability to pay attention in school. Otherwise she says that she has some headaches, but attributes this to migraines that run in her family. She does not take any medications, doesn't smoke, and drinks socially with her friends. On physical exam, a disfiguring red scalp rash is observed and radiographs reveal lytic appearing skull lesions. Further examination and testing would most likely reveal which of the following findings in this patient?", "answer": "Granules with tennis racket shape on electron microscopy", "options": {"A": "Anti-nuclear antibodies on serology", "B": "Granules with tennis racket shape on electron microscopy", "C": "HLA-B27 gene variant on genetic testing", "D": "Neoplastic CD2+ and CD4+ cells on serology", "E": "Noncaseating granulomas with multinucleated giant cells on histology"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 57-year-old man presents to the emergency department with a change in his mental status. His wife noticed he was particularly somnolent this evening which prompted her to bring him in. The patient has a past medical history of congestive heart failure, diabetes, and hypertension. His temperature is 99.5°F (37.5°C), blood pressure is 97/58 mmHg, pulse is 40/min, respirations are 17/min, and oxygen saturation is 95% on room air. A fingerstick blood glucose is notable for a value of 47 mg/dL. Which of the following is the best treatment for this patient?", "answer": "Glucagon", "options": {"A": "Atropine", "B": "Calcium chloride", "C": "Dextrose", "D": "Glucagon", "E": "Transcutaneous pacing"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 16-year-old boy comes to his primary care clinic for a sports physical. He states that he wants to try out for his high school’s football team this year. He's \"trying to get in better shape.” The patient has no complaints except for occasional headaches when he is stressed about exams. The patient also mentions that he is embarrassed of his “small penis” and asks if there is something he can take for that. The patient’s temperature is 98°F (36.7°C), blood pressure is 118/76 mmHg, and pulse is 79/min. On physical examination, the patient is obese and has no visible facial hair. His testes are less than 20 mL in volume, and his phallus measures less than 8 cm. Initial labs show testosterone levels of 95 ng/dL and a low follicle stimulating hormone/luteinizing hormone ratio. Which of the following is the next best diagnostic step?", "answer": "Thyroid-stimulating hormone and prolactin levels", "options": {"A": "Adrenocorticotrophic hormone stimulation test", "B": "Brain magnetic resonance imaging", "C": "Semen analysis", "D": "Spectral karyotype", "E": "Thyroid-stimulating hormone and prolactin levels"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 72-year-old man presents to the hospital with retrosternal chest pain and shortness of breath. The pain started 5 hours prior to arrival and has not changed after sublingual nitroglycerin intake. The patient has a history of long-standing persistent atrial fibrillation but had not been taking anticoagulants at the time of presentation. He had also been diagnosed with iron-deficiency anemia 3 months before admission and is taking 120 mg of elemental iron daily. He has no history of ischemic heart disease. Clinical investigation confirms inferior ST-elevation myocardial infarction with occlusion of the right coronary artery. The patient is managed with percutaneous coronary intervention (PCI). Six hours after the PCI, the patient develops cardiogenic shock; 8 hours after presentation, he dies, despite intensive care management. The autopsy reveals widespread inferior-posterior myocardial infarction and thrombotic occlusion of the left circumflex artery. The microscopic image depicts a macroscopically intact myocardium. Which of the following statements regarding this patient’s myocardial tissue is true?", "answer": "This slide shows changes in the myocardial tissue that result from lipid peroxidation during the patient's lifetime.", "options": {"A": "The slide depicts coagulative necrosis of the myocytes.", "B": "This slide shows changes in the myocardial tissue that result from lipid peroxidation during the patient's lifetime.", "C": "The changes shown on this slide are a result of iron overload.", "D": "The slide shows cardiac steatosis.", "E": "The microscopic image reveals cardiac tissue hypertrophy."}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 3-year-old boy is brought in by his parents for placement of a tracheostomy tube in order to allow for better ventilator support of his breathing. At birth, he was flaccid with a poor sucking reflex. Since then, his weakness has progressively worsened such that he is unable to sit, eat, or breathe independently. Family history reveals that his grandfather was affected by a degenerative disorder at age 50, and his father had the same degenerative disorder at age 30. Examination is significant for tongue fasciculations and absent deep tendon reflexes. Which of the following forms of inheritance is associated with the most likely cause of this patient's disorder?", "answer": "Autosomal recessive on chromosome 5", "options": {"A": "Autosomal dominant on chromosome 19", "B": "Autosomal recessive on chromosome 5", "C": "Autosomal recessive on chromosome 9", "D": "X-linked dominant", "E": "X-linked recessive"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 73-year-old man is brought to the emergency department 30 minutes after the sudden onset of right-sided body weakness. His wife reports that he does not seem to understand simple questions. He has type 2 diabetes mellitus and has smoked 1 pack of cigarettes daily for 45 years. The patient speaks fluently, but he answers questions with nonsensical phrases and cannot repeat single words. Which of the following is the most likely diagnosis?", "answer": "Wernicke aphasia", "options": {"A": "Conduction aphasia", "B": "Global aphasia", "C": "Wernicke aphasia", "D": "Transcortical sensory aphasia", "E": "Anomic aphasia"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 23-year-old woman comes to physician for an annual health maintenance examination. She feels well. She is 155 cm (5 ft 1 in) tall and weighs 79 kg (174 lb); BMI is 33 kg/m2. Examination shows a skin rash over both axillae. A photograph of her left axilla is shown. This patient's skin finding is most likely associated with which of the following conditions?", "answer": "Polycystic ovarian syndrome", "options": {"A": "Niacin deficiency", "B": "Primary adrenal insufficiency", "C": "Polycystic ovarian syndrome", "D": "Hashimoto thyroiditis", "E": "Pregnancy"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 72-year-old female is brought in by ambulance after being found down in her home. Her daughter discovered her after returning from work and does not know how long she has been down. Physical exam reveals right sided paralysis with a positive babinski sign. She is also found to produce strained stuttering speech with no perceivable meaning. She is unable to follow any instructions and cannot repeat speech. An MRI is obtained showing a left MCA infarct. Damage to which of the following structures is most likely to be responsible for her language deficits?", "answer": "Arcuate fasciculus + Inferior frontal gyrus + superior temporal gyrus", "options": {"A": "Arcuate fasciculus", "B": "Inferior frontal gyrus", "C": "Superior temporal gyrus", "D": "Inferior frontal gyrus + superior temporal gyrus", "E": "Arcuate fasciculus + Inferior frontal gyrus + superior temporal gyrus"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 66-year-old male with a history of diabetes and knee osteoarthritis presents to his primary care provider in July complaining of headaches and blurry vision. He reports a 6-month history of occasional dull diffuse headaches and blurry vision. He notes that the episodes have increased in severity since the weather got warmer and that he occasionally feels extremely itchy when he spends time outdoors. The patient lives in southern Arizona. Moreover, he has felt chronically fatigued and has lost 10 pounds without dieting or changing his appetite. He currently takes metformin and his most recent hemoglobin A1c was 6.5%. Physical examination reveals multiple bruises on the bilateral upper and lower extremities and hepatosplenomegaly. Fundoscopic examination demonstrates enlarged retinal veins. Multiple laboratory tests are pending. At steady state, which of the following sets of findings is most likely in this patient?", "answer": "Increased plasma volume, increased RBC mass, decreased EPO, normal SaO2", "options": {"A": "Increased plasma volume, increased RBC mass, decreased EPO, normal SaO2", "B": "Normal plasma volume, increased RBC mass, increased EPO, normal SaO2", "C": "Decreased plasma volume, normal RBC mass, normal EPO, normal SaO2", "D": "Normal plasma volume, increased RBC mass, increased EPO, decreased SaO2", "E": "Increased plasma volume, decreased RBC mass, decreased EPO, normal SaO2"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 25-year-old woman is brought to the emergency department for the evaluation of severe abdominal pain for the last hour. Abdominal ultrasound shows a non-compressible and enlarged appendix. The patient is diagnosed with acute appendicitis. While obtaining informed consent from the patient for appendectomy, the patient reports that she does not want to undergo surgery because she does not trust doctors. She states that all doctors are “bad” and all they think about is money. She adds that she thinks that nurses are “angels” and that they should take care of her instead of the “arrogant” doctors. This patient's behavior is characteristic of a condition that is most typically associated with which of the following?", "answer": "Self-injurious behavior", "options": {"A": "Paranoid delusions", "B": "Repeated performance of certain routines", "C": "Substance use disorder", "D": "Fear of social situations", "E": "Self-injurious behavior"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 20-year-old woman presents with persistent sadness for the last 2 months. She says that she is always feeling tired and nothing seems to cheer her up. Although previously a top student at her college, she did not register for classes this term, because she does not feel like going to school anymore. She says her friends complain that she does not want to ‘hang out’ with them anymore. She is sleeping more than usual and often does not want to leave the bed in the morning. The patient denies any suicidal ideation or preoccupation with death. Her past medical history is unremarkable. She currently takes a daily multivitamin. The vital signs include pulse 64/min, respiratory rate 12/min, blood pressure 110/70 mm Hg, and temperature 36.9°C (98.5°F). Her body mass index (BMI) is 17.5 kg/m2. On physical examination, the patient is pale. Mucous membranes and oral cavity are dry with poor dentition. Multiple calluses are present on the knuckles of her left hand. Which of the following medications is the best course of treatment in this patient?", "answer": "Mirtazapine", "options": {"A": "Trazodone", "B": "Mirtazapine", "C": "Lorazepam", "D": "Bupropion", "E": "Amitriptyline"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 31-year-old man presents to the clinic with complaints of sudden onset of fever, headache, chills, and a painful “bump” in his right groin. He recently spent three months working as a park ranger in New Mexico. His physical exam is notable for an enlarged lymph node in the inguinal region that is extremely tender to palpation. The patient is promptly treated with antibiotics, and his case is reported to the Centers for Disease Control and Prevention. Which of the following was the most likely vector that transmitted the disease to this for patient?", "answer": "Flea", "options": {"A": "Armadillo", "B": "Flea", "C": "Louse", "D": "Rat", "E": "Tick"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "As the only full-time inpatient endocrinologist at your hospital, you have been tasked with deciding which blood glucose measuring device to use on the wards. A medical device representative presents you with the data in Image A. All readings were performed on the same individual whose blood glucose was known to be 125 mg/dL at the time. Which of the devices has the best precision?", "answer": "Device D", "options": {"A": "Device A", "B": "Device B", "C": "Device C", "D": "Device D", "E": "Not enough information provided"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 21-year-old male comes to the physician’s office with complaints of fatigue. The patient is a college intramural athlete and has noticed that during hard workouts with his team, he gets severe muscle pain and weakness to the point where he has to stop and rest. Usually he is able to recover and the cramps subside after rest. After strenuous workouts he has also noticed that his urine is dark. On exam, the patient has no acute symptoms and appears to be sitting comfortably with a completely normal exam. The patient does not have any tenderness to palpation of his muscles. Which of the following enzymes is most likely defective in this patient?", "answer": "Glycogen phosphorylase", "options": {"A": "Glucose-6-phosphatase", "B": "Debranching enzyme", "C": "Glycogen phosphorylase", "D": "Galactocerebrosidase", "E": "Acid maltase"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 78-year-old man comes to the physician because of a 3-week history of dyspnea, chest pain, dry cough, painful swallowing, and a feeling of fullness in his head. The symptoms were initially mild but have progressively worsened. He has a history of gastroesophageal reflux disease treated with esomeprazole. He does not smoke cigarettes. His pulse is 99/min and blood pressure is 95/66 mm Hg. Examination shows swelling and redness of the face and neck. There is distention of the superficial veins of his neck and upper thorax. Plain radiographs of the chest show a widened mediastinum and unremarkable lung fields. Which of the following is the most likely underlying cause of this patient's symptoms?", "answer": "Mediastinal lymphoma", "options": {"A": "Pancoast tumor", "B": "Cardiac tamponade", "C": "Constrictive pericarditis", "D": "Descending aortic aneurysm", "E": "Mediastinal lymphoma"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 52-year-old man is brought to the emergency department 30 minutes after his farmhand found him on the ground sweating profusely. On arrival, he is lethargic and unable to provide any history. His temperature is 37.5°C (99.5°F), pulse is 42/min, and blood pressure is 95/60 mm Hg. Physical examination shows diaphoresis and excessive salivation. The pupils are constricted. There is scattered expiratory wheezing throughout both lung fields. His clothes are soaked with vomit, urine, and feces. A drug with which of the following mechanisms of action is most appropriate for this patient?", "answer": "Muscarinic acetylcholine receptor antagonism", "options": {"A": "Non-selective α adrenergic receptor antagonism", "B": "β2 adrenergic receptor agonism", "C": "Muscarinic acetylcholine receptor antagonism", "D": "Acetylcholinesterase enzyme inhibition", "E": "Nicotinic acetylcholine receptor agonism"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 40-year-old woman is admitted to the hospital about four hours after her husband discovered that she ingested a bottle of acetaminophen in an attempted suicide. The patient denies any symptoms at this time. Vital signs include a blood pressure of 115/80 mmHg and pulse of 85/min. Physical exam is unremarkable. AST and ALT levels are approximately 2500 U/L. APAP level is 160 mcg/mL, and INR is 1.7. The patient refuses N-acetyl-cysteine (NAC) treatment. What is the best next step in management?", "answer": "Involve the patient's husband to guide medical care", "options": {"A": "Administer NAC", "B": "Cancel the NAC order", "C": "Involve the patient's husband to guide medical care", "D": "Force the patient to accept NAC", "E": "Consult psychiatry"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "An 11-month-old baby boy is brought to the emergency room by his parents for vomiting. His mom reports that he has had a cold for the past week with a runny nose and low-grade fevers. However, his condition worsened today when he began coughing and struggling to breathe. During one of his coughing spells he threw up his milk as well. The parents deny any sick contacts, changes in diet, or bowel changes but endorse fatigue and decreased appetite. A physical examination demonstrates a healthy-looking baby with an intense cough and significant inspiratory stridor. What is the pathophysiology of this patient’s condition?", "answer": "Toxin that inactivates Gi protein", "options": {"A": "Generation of reactive oxygen species", "B": "Production of IgA proteases", "C": "Toxin that inactivates elongation factor-2", "D": "Toxin that inactivates Gi protein", "E": "Toxin that permanently activates Gs protein"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 56-year-old male undergoes a pancreaticoduodenectomy for resection of a tumor of the head of the pancreas. His medical history is otherwise insignificant except for a series of minor respiratory and gastrointestinal infections since childhood that were effectively treated with antibiotics. Before today, he has not had any prior surgeries or required a blood transfusion. In the post anesthesia care unit, his hemoglobin is measured and found to be 5.2 g/dL. A transfusion of 2 units of packed red blood cells is ordered. Minutes after the transfusion is initiated, the patient reports severe itching, nausea, and shortness of breath. His vital signs show a drop in blood pressure from 138/88 to 92/47 and an increase in heart rate from 94 to 118. The patient's nurse stops the transfusion immediately. Which of the following underlying conditions most likely predisposed this patient to develop this reaction?", "answer": "Selective IgA deficiency", "options": {"A": "Severe combined immunodeficiency disorder", "B": "Bruton's agammaglobulilnemia", "C": "Wiskott-Aldrich syndrome", "D": "IL-12 deficiency", "E": "Selective IgA deficiency"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 5-year-old girl is brought to the emergency department after sustaining an atraumatic tibial fracture while playing with her friends. This patient has a history of fractures in her upper and lower extremities. Children's services have investigated the family several times in the past and found no abuse. She was born at 39 weeks gestation via spontaneous vaginal delivery which resulted in several mild fractures. She is up to date on all vaccines and is meeting all developmental milestones. The mother has a brother with a similar history that is still living. Her vital signs show a heart rate of 90/min, respiratory rate of 22/min, blood pressure of 110/65 mm Hg, and temperature of 37.0°C (98.6°F). Physical exam reveals a regular heart rate, and her lungs are clear to auscultation bilaterally. The sclera of both eyes are blue. Additionally, her teeth are brown and distorted. Her leg is swollen, erythematous, and tender to palpation. An X-ray reveals a tibia fracture, while multiple fractures at various stages of healing are also seen on her arms. The physician suspects this is a genetic condition. Which of the inheritance patterns can be attributed to the girl’s condition?", "answer": "Locus heterogeneity", "options": {"A": "Incomplete penetrance", "B": "Pleiotropy", "C": "Anticipation", "D": "Locus heterogeneity", "E": "De novo mutation"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 72-year-old woman presents to her primary care physician because she is coughing pink sputum and has difficulty breathing. She says that she was feeling pretty good until she traveled to her grandson's wedding last week. Since then she has had increasing difficulty sleeping and walking due to her shortness of breath. Physical exam reveals swollen ankles, basilar crackles bilaterally, and a murmur best heard in the left lateral decubitus position. She is already taking several medications for this condition; however, given the recent worsening of symptoms she is started on an additional medication. Which of the following is the most likely mechanism of action for the medication that was started in this patient?", "answer": "Inhibition of Na-K-Cl cotransporter", "options": {"A": "Competitive inhibition of hormonal signaling", "B": "Decrease in adenylyl cyclase activity", "C": "Inhibition of Na-Cl symporter", "D": "Inhibition of Na-K-Cl cotransporter", "E": "Relaxation of vascular smooth muscle"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 37-year-old woman is brought to the emergency department for acute abdominal pain for the past 2 hours. She reports that the pain is constant, 10/10, and is diffusely spread across her stomach. She reports nausea and 1 episode of vomiting 1 hour ago, painless bloody urine, and paresthesias in her hands bilaterally. The patient claims similar episodes in the past following the use of alcohol, though with milder pain. Her past medical history is significant for pelvic inflammatory disease that was adequately treated 5 years ago. She is currently sexually active with her husband without contraceptive use. Her temperature is 98.6°F (37°C), blood pressure is 148/98 mmHg, pulse is 103/min, respirations are 18/min, and oxygen saturation is 99% on room air. A physical examination demonstrates a patient in acute distress with diffuse abdominal tenderness and decreased sensation of the hands bilaterally. What is the most likely explanation for this patient’s symptoms?", "answer": "Mutation of the porphobilinogen deaminase enzyme", "options": {"A": "Implantation of the embryo outside of the uterus", "B": "Inflammation of the appendix", "C": "Inflammation of the pancreas", "D": "Mutation of the porphobilinogen deaminase enzyme", "E": "Obstruction of the cystic duct and subsequent inflammation of the gallbladder"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A medical research study is being conducted to evaluate the specificity of a novel blood test for rheumatoid arthritis. Of the 300 patients enrolled, half are diagnosed with RA. The remaining patients are age-matched controls. In the subgroup of patients with RA, 125 are found positive for the novel blood test. In the control group, 45 are found positive. Which of the following represents the overall specificity of this novel test?", "answer": "105 / (105 + 45)", "options": {"A": "105 / (105 + 25)", "B": "125 / (125 + 105)", "C": "125 / (125 + 45)", "D": "105 / (105 + 45)", "E": "125 / (125 + 25)"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 58-year-old man comes to the emergency department because of multiple episodes of coughing up blood over the past 2 hours. He says that he has coughed up approximately half a cup of bright-red blood each time. He has had progressively worsening shortness of breath on exertion and a productive cough with occasionally blood-tinged sputum for the past 6 months. He has a history of hypertension and chronic obstructive pulmonary disease. He has worked in a car manufacturing company for over 20 years. He drinks 2 to 3 beers every evening. He has smoked 1 pack of cigarettes daily for the past 30 years. His medications include amlodipine, tiotropium, and an albuterol inhaler as needed. His temperature is 37.2 °C (99.0 °F), blood pressure is 102/68 mm Hg, pulse is 108/min, and respirations are 22/min. Pulse oximetry on room air shows an oxygen saturation of 89%. He appears anxious and cachectic. Examination of the lung shows decreased breath sounds bilaterally. There is no cervical or axillary lymphadenopathy. His hemoglobin is 11.5 g/dL, leukocyte count is 8,800/mm3, and a platelet count is 160,000/mm3. His coagulation parameters are within normal limits. Serum studies and urine analysis show no abnormalities. He is intubated and mechanically ventilated, and infusion of 0.9% saline is begun. An x-ray of the chest shows hyperinflation of the lung fields and a 2-cm nodule in the right lower lobe. In addition to placing the patient in the right lateral decubitus position, which of the following is the most appropriate next step in management?", "answer": "Bronchoscopy", "options": {"A": "Radionuclide scan", "B": "CT scan of the chest", "C": "Upper endoscopy", "D": "Arteriography", "E": "Bronchoscopy"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A previously healthy 3-year-old girl is brought to the physician because she refuses to use her left arm after “tripping over a stone” that morning on the way to the supermarket while holding her mother's hand. She did not hit the ground. Development has been normal for her age. She appears anxious. Her vital signs are within normal limits. The left forearm is held close to her body in partial extension and pronation. There is no swelling or bruising of the elbow or the forearm. Palpation of the proximal radius produces pain. The child cries on attempting to passively supinate the forearm. Which of the following is the most appropriate next step for the physician?", "answer": "Forced hyperpronation of the arm", "options": {"A": "Administer ibuprofen and ice packs", "B": "Forced hyperpronation of the arm", "C": "Notify child protective services", "D": "Obtain rheumatoid factor and antinuclear antigen assay", "E": "Perform nerve conduction studies and electromyography\n\""}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A previously healthy 29-year-old woman comes to the physician because of a 3-day history of low-grade fever, muscle aches, and a rash. She has had 4 male sexual partners over the past year and uses condoms inconsistently. Examination shows a diffuse maculopapular rash that includes the palms and soles. Testing for nonspecific anticardiolipin antibodies is positive. Which of the following is the most appropriate next step in management?", "answer": "Test for fluorescent treponemal antibody absorption", "options": {"A": "Assess for double-stranded DNA antibodies", "B": "Obtain bacterial culture", "C": "Administer penicillin G", "D": "Analyze rash with darkfield microscopy", "E": "Test for fluorescent treponemal antibody absorption"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 59-year-old man with New York Heart Association Class II heart failure presents to your outpatient clinic for routine follow-up. His blood pressure is 134/89 mm Hg and heart rate is 75/min. Physical examination reveals clear lung sounds bilaterally with normal S1 and S2 heart sounds. He currently takes captopril, bisoprolol, and furosemide. You would like to add on spironolactone. Of the following, which is true regarding aldosterone antagonists in patients with heart failure?", "answer": "Aldosterone antagonists decrease morbidity and mortality in heart failure patients", "options": {"A": "Aldosterone antagonists do not require renal dosing", "B": " Aldosterone antagonists are indicated for patients in all stages of heart failure", "C": "Aldosterone antagonists decrease morbidity and mortality in heart failure patients", "D": "Aldosterone antagonists can cause visual disturbances", "E": "Aldosterone antagonists may precipitate a cough in heart failure patients"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 32-year-old man comes to the physician because of a 1-week history of fever, nausea, headache, and confusion. Three weeks ago, he had an episode of a sore throat, diarrhea, and generalized lymphadenopathy. He is sexually active with a new partner that he met 2 months ago and they use condoms inconsistently. He appears ill. Physical examination shows nuchal rigidity. Further evaluation shows infection with a single-stranded, positive-sense RNA virus. The cells most likely affected in this patient’s current condition are analogous to which of the following cell types?", "answer": "Langerhans cells", "options": {"A": "Ependymal cells", "B": "Osteoblasts", "C": "Mast cells", "D": "Schwann cells", "E": "Langerhans cells"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 64-year-old man presents for a routine physical. He states that he has felt abnormally weak during this time and has had trouble focusing in the setting of losing 5 pounds. The patient states he has a decreased appetite and also has not had a bowel movement in the past 5 days and feels uncomfortable. On review of system, he endorses abdominal pain. His temperature is 97.5°F (36.4°C), blood pressure is 132/83 mmHg, pulse is 115/min, respirations are 15/min, and oxygen saturation is 98% on room air. Physical exam is notable only for the patient being able to recall 1 of 3 objects. His cranial nerve exam is unremarkable and his gait is stable. Urinalysis is initially notable for a clear and voluminous sample with a low specific gravity. Which of the following tests is most likely abnormal in this patient?", "answer": "Calcium level", "options": {"A": "Calcium level", "B": "Lead level", "C": "Phosphate level", "D": "Potassium level", "E": "TSH level"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "Ten days after a motor vehicle collision, a 28-year-old man develops jaundiced skin. Upon initial presentation for his injuries, the patient was taken for an emergency laparotomy, which revealed significant internal hemorrhage from blunt abdominal trauma to the spleen. He required rapid transfusion with a total of 7 units of packed red blood cells. He has recovered well from the procedure until this morning, when he began to develop jaundiced skin and sclerae. He does not have pruritus. He has had no prior surgeries and takes no other medications. He is sexually active with one female partner. Prior to the accident, he drank 4 beers per day. His vital signs are within normal limits. Abdominal examination is limited due to pain. There are no palpable abdominal masses. There is a midline surgical scar with no erythema, purulence, or drainage. He has healing abrasions on the upper left side of his face and bruises over the anterior abdomen. CT scans show a resolving hematoma in the peritoneal cavity. Laboratory studies show:\nHemoglobin 9.7 g/dL\nHematocrit 30%\nLeukocyte count 7,000/mm3\nPlatelet count 135,000/mm3\nSerum\nTotal bilirubin 3.9 mg/dL\nIndirect bilirubin 3.7 mg/dL\nDirect bilirubin 0.2 mg/dL\nAspartate aminotransferase (AST) 60 U/L\nAlanine aminotransferase (ALT) 92 U/L\nWhich of the following is the most likely cause of this patient's jaundice?\"", "answer": "Increased formation of bilirubin", "options": {"A": "Biliary obstruction", "B": "Hepatocellular injury", "C": "Increased formation of bilirubin", "D": "Impaired conjugation of bilirubin", "E": "Decreased hepatic uptake of unconjugated bilirubin\n\""}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 69-year-old man comes to the physician because of a cough for the past 3 months. The cough is mostly dry, but the patient recalls a recent episode in which he coughed up mucus with dark red streaks. He has felt tired for the past few months. Over the past month, he has had poor appetite and a 5-kg (11-lb) weight loss. He also has occasional back pain, which has worsened in recent weeks. He has no recent travel history. He has smoked a pack of cigarettes daily for 30 years. He does not drink alcohol. His vitals are within normal limits. Auscultation of the lungs reveals wheezing in the lower right lung field. There is no peripheral lymphadenopathy. The liver is of normal size, and the spleen is not palpable. Laboratory studies show a hemoglobin concentration of 13.5 g/dL, serum calcium concentration of 12.3 mg/dL, and a total serum protein of 7.0 g/dL. X-rays of the chest are shown. Which of the following is the most likely diagnosis?", "answer": "Squamous cell lung carcinoma\n\"", "options": {"A": "Tuberculosis", "B": "Lobar pneumonia", "C": "Small cell lung carcinoma", "D": "Sarcoidosis", "E": "Squamous cell lung carcinoma\n\""}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 37-year-old man comes to the physician because of a 3-month history of worsening painful swallowing, hoarseness, and bilateral otalgia. He has had a 10-kg (22-lb) weight loss during this period. He does not smoke or drink alcohol. Laryngoscopic examination shows an abnormal mass located on the right true vocal cord. Immunohistochemistry of the mass shows expression of HPV-16 DNA. This neoplasm most likely derived from which of the following types of epithelial tissue?", "answer": "Stratified squamous epithelium with submucosal glands", "options": {"A": "Stratified squamous epithelium with submucosal glands", "B": "Simple columnar epithelium with cilia", "C": "Pseudostratified columnar epithelium with cilia", "D": "Pseudostratified columnar epithelium with cartilage", "E": "Simple cuboidal epithelium with club cells"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "An investigator is studying patients with an autosomal dominant mutation in the long arm of chromosome 10. This mutation alters the structure of CD95 receptors and impairs the binding of a ligand to this receptor. These patients are at greatest risk for which of the following complications?", "answer": "Autoimmune cytopenia", "options": {"A": "Partial albinism", "B": "Parathyroid aplasia", "C": "Autoimmune cytopenia", "D": "Acute myeloid leukemia", "E": "Diabetes mellitus"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "An investigator is studying cardiovascular changes during exercise. He is following a 25-year-old female volunteer who is training for a marathon. Her training consists of running on a treadmill for increasing amounts of time. During her training sessions, laboratory studies show increased concentrations of adenosine and lactate in the active muscles. Which of the following is most likely a direct effect of these metabolites?", "answer": "Decreased systemic vascular resistance", "options": {"A": "Decreased stroke volume", "B": "Decreased capillary pressure", "C": "Decreased systemic vascular resistance", "D": "Increased venous return", "E": "Increased mixed venous oxygen saturation"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A previously healthy 16-year-old girl is brought to the physician by her parents because of behavior changes and involuntary limb movements over the past 2 days. She also has a 2-week history of fever, headache, and fatigue. Her temperature is 38°C (100.4°F), pulse is 110/min, respirations are 20/min, and blood pressure is 102/72 mm Hg. Mental status examination shows impaired speech and a disorganized thought process. Muscle strength is 5/5 in all extremities. Urine toxicology screening is negative. Cerebrospinal fluid analysis shows a leukocyte count of 70 cells/mm3 (90% lymphocytes) and a protein concentration of 51 mg/dL. Abdominal ultrasound shows a large right adnexal mass. The patient's symptoms are most likely caused by antibodies against which of the following?", "answer": "Glutamate receptors", "options": {"A": "Purkinje cell Yo antigens", "B": "GM1 ganglioside", "C": "Acetylcholine receptors", "D": "Neuronal Hu antigens", "E": "Glutamate receptors"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 7-year-old boy is brought to the physician by his mother because of low-grade fevers and a cough lasting for 2 weeks. He has vomited several times after fits of coughing. He has no history of serious illness and has not received any routine childhood vaccinations. His temperature is 38.3°C (101°F). Physical examination shows erythema of the nasal and oral mucosa. While in the exam room, he has a long series of consecutive coughs, during which he appears diaphoretic. The coughing is followed by a loud inspiratory gasp. Laboratory studies show a leukocyte count of 16,300/mm3 (67% lymphocytes). The pathogen most likely responsible for this patient's presentation contains a toxin that acts by which of the following mechanisms?", "answer": "Increases intracellular cAMP", "options": {"A": "Increases intracellular cAMP", "B": "Increases intracellular cGMP", "C": "Inactivates host elongation factor", "D": "Inactivates host 60S ribosome", "E": "Activates Gi-coupled protein receptors"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 21-year-old college student is rushed to the ER because of a high-grade fever that started this morning. She vomited several times last night. She is complaining of a severe, unremitting headache. Her temperature is 38.9°C (102.0°F), respiratory rate is 20/min, pulse is 112/min, and blood pressure is 105/78 mm Hg. She is highly sensitive to light. Her neck feels stiff on passive flexion, with positive Kernig’s and Brudzinski’s signs. There is a non-blanching maculopapular rash all over the body. Cerebrospinal fluid (CSF) samples are sent to the lab for analysis and she is started on intravenous fluids and antibiotics. The CSF analysis will most likely reveal which of the following?", "answer": "Polymorphonuclear leukocytosis", "options": {"A": "Elevated glucose concentration", "B": "Eosinophils", "C": "Decreased protein concentration", "D": "Lymphocytosis", "E": "Polymorphonuclear leukocytosis"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 58-year-old man with chronic obstructive pulmonary disease and hypertension comes to the physician because of shortness of breath 3 days after starting propranolol. His temperature is 36.7°C (98.1°F), pulse is 64/min, respirations are 20/min, and blood pressure is 138/88 mm Hg. Auscultation of the lungs shows diffuse expiratory wheezes. In addition to discontinuing the propranolol, which of the following drugs should be administered?", "answer": "Albuterol", "options": {"A": "Albuterol", "B": "Prednisone", "C": "Glucagon", "D": "Tiotropium bromide", "E": "Theophylline"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 6-year-old boy is admitted with a one-week history of diarrhea, which was sometimes bloody and originally began after a birthday party. He has become lethargic and has not been eating or drinking. His vital signs are as follows: T 38.5 C, HR 135, BP 82/54. Physical examination is significant for petechiae on his legs and diffuse abdominal tenderness to palpation. Lab-work shows BUN 72 mg/dL, creatinine 8.1 mg/dL, and platelet count < 10,000. PT and PTT are within normal limits. Which of the following would be expected on a peripheral blood smear?", "answer": "Fragmented red blood cells", "options": {"A": "Rouleaux formation", "B": "Fragmented red blood cells", "C": "Spur cells", "D": "Giant platelets", "E": "No abnormalities"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A microbiology student is studying the different types of cell surface markers on immune cells. He is interested in the human major histocompatibility complex (MHC) and human leukocyte antigens (HLAs). While studying, he learns that both class I and class II MHC molecules are expressed on specific types of cells. Currently, he is studying the HLA-DP, HLA-DQ, HLA-DRα, and HLA-DRβ genes. Which of the following cells express molecules encoded by these genes?", "answer": "Thymic epithelial cells", "options": {"A": "Eosinophils", "B": "Mesenchymal cells", "C": "Platelets", "D": "T lymphocytes", "E": "Thymic epithelial cells"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 10-year study of 1,000 residents in a small US town is conducted to determine the risk of developing lung cancer. The study assesses each subject with a comprehensive physical exam and chest X-ray at 3-time points: at baseline, at the 5-year point, and at the conclusion of the study. At each time point, the total number of cases of lung cancer in the population is recorded. The data gathered from the study are given in the table below:\nTime point Total cases of lung cancer\nt = 0 years 100\nt = 5 years 500\nt = 10 years 600\nWhich of the following is the incidence of lung cancer per 1,000 people per year?", "answer": "87", "options": {"A": "104", "B": "50", "C": "0.6", "D": "87", "E": "125"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 7-year-old boy suffers from generalized edema. Urine protein excretion is 5.2 g over 24 hours, and serum analysis reveals hyperlipidemia. The patient responds to treatment with prednisone, and, 8 weeks later, his urine does not contain measurable protein. If a kidney biopsy had been performed while the patient’s condition was pathologic, which of the following would you expect to find upon glomerular electron microscopy?", "answer": "Effacement of podocyte foot processes", "options": {"A": "Effacement of podocyte foot processes", "B": "Subepithelial ‘spike and dome’ deposits", "C": "Subepithelial humps", "D": "Thin glomerular basement membrane", "E": "Subendothelial thickening"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A previously healthy 3-month-old girl is brought to the emergency department because her lips turned blue while passing stools 20 minutes ago. She has not stopped crying since then. She was born at 38 weeks' gestation. She is at the 50th percentile for length and below the 30th percentile for weight. She is alert and agitated. Her temperature is 36.6°C (98°F), pulse is 180/min, respirations are 50/min, and blood pressure is 70/50 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 70%, which increases to 81% on administration of 100% oxygen. Physical examination shows perioral cyanosis and retractions of the lower ribs with respiration. Cardiac examination shows a harsh grade 2/6 systolic crescendo-decrescendo murmur at the left upper sternal border. Which of the following would most likely improve this patient's symptoms?", "answer": "Knee-chest positioning", "options": {"A": "Knee-chest positioning", "B": "Supine positioning", "C": "Hyperextension of the neck", "D": "Lower limb elevation", "E": "Prone positioning"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "An 8-year-old girl of Asian descent is brought to the physician because of fatigue. She is not able to keep up with the rest of her classmates in gym class because she tires easily. Physical examination shows pale conjunctivae. Laboratory studies show:\nHemoglobin 11.0 g/dL\nMean corpuscular volume 74 μm3\nRed cell distribution width 14 (N=13-15)\nSerum ferritin 77 ng/mL\nPeripheral blood smear shows small, pale red blood cells. Hemoglobin electrophoresis is normal. Which of the following best describes the pathogenesis of the disease process in this patient?\"", "answer": "Cis deletion of α-globin genes", "options": {"A": "Decreased production of β-globin proteins", "B": "Amino acid substitution in the β-globin protein", "C": "Cis deletion of α-globin genes", "D": "Inadequate intake of iron", "E": "Acquired inhibition of heme synthesis"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 52-year-old postmenopausal woman comes to the physician with a 6-month history of difficulty biting down and chewing that is becoming progressively worse. She has been taking acetaminophen for headaches and nonspecific pain in her hips and back. She also complains that her hearing has been deteriorating as she gets older. Vital signs are within normal limits. Examination shows a mildly tender, 1-cm, bony, immobile swelling in the left side of her forehead. Intraoral examination shows bilateral expansion of the maxillary alveolus and malocclusion. Audiometry shows bilateral mixed conductive and sensorineural hearing loss. Laboratory studies show:\nHemoglobin 14.6 g/dL\nLeukocyte count 9,000/mm3\nPlatelet count 256,000/mm3\nSerum\nAlkaline phosphatase 1100 U/L\nVitamin D 40 ng/ml (N = 20–100 ng/mL)\nCalcium 9.5 mg/dL\nParathyroid hormone 300 pg/mL\nA plain x-ray of the skull is shown. Which of the following is the most appropriate next step in management?\"", "answer": "Intravenous zoledronate", "options": {"A": "Hematopoietic cell transplantation", "B": "Transsphenoidal hypophysectomy", "C": "Surgery and adjuvant chemotherapy", "D": "Intravenous zoledronate", "E": "Estrogen replacement therapy"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 66-year-old man is brought to the emergency department because of worsening shortness of breath and progressive swelling of his legs for 1 week. He has hypertension and hyperlipidemia. Current medications include amlodipine and pravastatin. His temperature is 37.5°C (99°F), pulse is 95/min, respirations are 12/min, and blood pressure is 113/70 mm Hg. Pulmonary examination shows bilateral coarse crackles. An S3 gallop is heard on auscultation. There is jugular venous distension and pitting edema of both ankles. He is admitted to the hospital and treatment with intravenous bumetanide is initiated. Serum studies obtained 5 days after admission show:\nNa+ 138 mEq/L\nCl− 101 mEq/L\nMg2+ 1.3 mEq/L\nUrea nitrogen 42 mg/dL\nCreatinine 1.8 mg/dL\nArterial blood gas analysis on room air:\npH 7.51\nPCO2 52 mm Hg\nPO2 60 mm Hg\nHCO3- 33 mmol/L\nFurther evaluation of this patient is most likely to show which of the following findings?\"", "answer": "Elevated serum aldosterone", "options": {"A": "Elevated serum aldosterone", "B": "Decreased urine chloride", "C": "Decreased serum renin", "D": "Elevated serum potassium", "E": "Decreased serum vasopressin"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 16-year-old boy is brought to the emergency department by his parents after collapsing at home. He was resting at home after an uneventful dental procedure that involved the extraction of several teeth. He became drowsy and then unconscious and was unrousable. At the hospital, his temperature is 37.0° C (98.6° F), respiratory rate is 15/min, pulse rate is 67/min, and blood pressure is 122/98 mm Hg. Oxygen saturation is 85% on room air. The patient is deeply cyanosed despite a good respiratory effort and a clear airway. His lungs are clear to auscultation, bilaterally. Even though an endotracheal tube is introduced and assisted ventilation is induced, his condition does not improve. A review of dental records reveals the details of the procedure where the local anesthetic pilocarpine was administered. What is the most likely cause of this patient’s condition?", "answer": "Methemoglobinemia", "options": {"A": "Cyanide poisoning", "B": "Methemoglobinemia", "C": "Anaphylactic reaction", "D": "Sulfhemoglobinemia", "E": "Carbon monoxide poisoning"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "Please refer to the summary above to answer this question\nWhich of the following is the most likely underlying cause of this patient's upper extremity symptoms?\"\n\"Patient Information\nAge: 1 day\nSex: F\nEthnicity: Hispanic\nSite of Care: office\nHistory\nReason for Visit/Chief Concern: brought in by her parents because “her arm looks funny”\nHistory of Present Illness:\nmother had no prenatal care\nlabor was spontaneous with rupture of membranes yielding fluid with dark green streaks\nthe infant was delivered vaginally 1 day ago at home at approximately 39 weeks' gestation\nthe delivery was complicated by shoulder dystocia, which was managed with suprapubic pressure and the McRoberts maneuver\nfather reports that the infant's right arm “just hangs by the side” and that she never bends her right elbow\nthe infant is breastfeeding, stooling, and voiding without complication\nPast Medical History:\nnone\nFamily History:\nmother has type 2 diabetes mellitus\nMedications:\nnone\nImmunizations:\nhas not received any routine vaccinations\nAllergies:\nno known drug allergies\nSocial History:\nthe infant lives with her mother, father, and paternal grandmother\nno one in the residence smokes\nPhysical Examination\nTemp Pulse Resp BP O2 Sat Ht Wt Head circumference\n37.1°C\n(98.8°F)\n154/min 45/min 87/49 mm Hg\n99%\n50 cm\n(20 in; 69th percentile)\n4,400 g\n(9 lb 11 oz; 99th percentile)\n35 cm\n(13.8 in; 82nd percentile)\nAppearance: well-appearing; crying during the examination\nHEENT: red reflex is seen bilaterally; there is a fluctuant area over the left parietal bone that crosses suture lines\nPulmonary: clear to auscultation\nCardiac: regular rate and rhythm; normal S1 and S2; no murmurs, rubs, or gallops\nAbdominal: no tenderness, masses, or hepatosplenomegaly; bowel sounds normal; umbilical stump is intact and clamped\nExtremities: hips are stable bilaterally\nMusculoskeletal: clavicles are intact bilaterally; the right upper extremity hangs limply from the shoulder in full extension, adduction, and fixed internal rotation; the hand is pronated, and the wrist and fingers are flexed\nSkin: dry, warm; no jaundice\nNeurologic: normal suck and grasp reflexes; the Moro reflex is normal in the left upper extremity and absent in the right upper extremity; deep tendon reflexes are 2+ bilaterally\"", "answer": "Damage to the upper trunk of the brachial plexus", "options": {"A": "Injury to the median nerve", "B": "Damage to the upper trunk of the brachial plexus", "C": "Damage to the lower trunk of the brachial plexus", "D": "Asphyxia during the delivery", "E": "Aspiration of meconium"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 34-year-old man presents with severe left inguinal pain and swelling since last night. He has just returned from a summer trip to the southwestern United States where he spent most of his time working with homeless and unemployed people in an area that straddles New Mexico and Utah. Upon further inquiry, he denies any contact with wild or domestic animals including pets, but he does remember occasionally seeing mice in his motel room and found their droppings on the floor. On physical exam his temperature is 38.5°C (101.3°F), pulse is 95/min, respiration rate is 18/min, and blood pressure is 130/85 mm Hg. The left inguinal area is swollen. There is no skin erythema and it is not warm to palpation. There are several enlarged and soft lymph nodes with a hard underlying core. The area is very tender and surrounded by edema. A localized rash is found in the ipsilateral inner thigh above the knee (see image). Examination of the heart, lungs, abdomen, and other limbs shows no abnormalities. Which of the following pathogens is the most likely cause of this patient’s condition?", "answer": "Yersinia pestis", "options": {"A": "Bartonella henselae", "B": "Hantavirus", "C": "Rhabdovirus", "D": "Borrelia burgdorferi", "E": "Yersinia pestis"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 10-year-old unvaccinated girl presents to her pediatrician with a rash. Her mother reports that she has had a fever, “red eyes,” sore throat, and rash on her face for the last day. On physical examination, the girl appears sick but not toxic, and has nonpurulent conjunctivitis and an erythematous posterior pharynx without exudate or tonsillar hypertrophy. She has lymphadenopathy bilaterally. Her heart has a regular rate without murmurs, her lungs are clear to auscultation bilaterally, and her abdomen is soft without hepatosplenomegaly. She has red cheeks with circumoral pallor and no other skin findings. Which of the following is the most appropriate advice for this patient’s mother?", "answer": "She will likely develop a maculopapular truncal rash in a few days that will fade to become a lacy rash.", "options": {"A": "This infection could have been prevented with a vaccine.", "B": "Her symptoms were caused by human herpesvirus type 6 (HHV-6) or human herpesvirus type 7 (HHV-7).", "C": "She will likely develop a maculopapular truncal rash in a few days that will fade to become a lacy rash.", "D": "As a result of this illness, she may develop shingles later in life.", "E": "She should be started on oral valacyclovir."}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 42-year-old woman presents to the clinic for worsening fatigue and difficulty breathing for the last 6 months. Previously, she could routinely walk 3 miles after dinner, but now she can no longer walk more than 2 blocks without being short of breath. She also reports being tired soon after starting any type of physical activity. On further questioning, she recalls having on and off fevers, occasional night sweats, and losing 5 kg (11 lb) over the last 6 months. Her past medical history reveals 2 cesarean deliveries in her twenties and a hospitalization for acute appendicitis in her teens. She currently takes no medications and also denies smoking and recreational drug use. She drinks half a glass of wine with her evening meals. Her vitals include a respiratory rate of 14/min, a pulse rate of 87/min, a blood pressure of 110/89 mm Hg, and a temperature of 36.7°C (98.0°F). Physical examination is normal. A chest X-ray shows bilateral hilar lymphadenopathy. Which of the following changes in forced expiratory volume (FEV1) and forced vital capacity (FVC) are expected if she takes a pulmonary function test?", "answer": "FEV1: decrease and FVC: decreased", "options": {"A": "FEV1: decrease and FVC: decreased", "B": "FEV1: decreased and FVC: no change", "C": "FEV1: decreased and FVC: increased", "D": "FEV1: no change and FVC: no change", "E": "FEV1: no change and FVC: decreased"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 42-year-old woman is brought to the emergency department because of a severe, throbbing, occipital headache for 2 hours. She also reports nausea, photophobia, and chest tightness. The symptoms developed shortly after she had a snack consisting of salami and some dried fruits at a wine tasting event. The patient has recurrent migraine headaches and depression, for which she takes medication daily. She is mildly distressed, diaphoretic, and her face is flushed. Her temperature is 37.2°C (98.9 F), pulse is 88/min, respirations are 19/min, and blood pressure is 190/128 mmHg. Deep-tendon reflexes are 2+ bilaterally. This patient's symptoms are most likely caused by a side effect of which of the following medications?", "answer": "Tranylcypromine", "options": {"A": "Naproxen", "B": "Tranylcypromine", "C": "Almotriptan", "D": "Topiramate", "E": "Doxepin"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 70-year-old man is brought to the emergency department because of severe back pain that began when he was lifting a box 1 hour ago. He also has a 2-year history of increasingly severe right hip pain. Physical examination shows tenderness to palpation of the lower spine as well as erythema of the skin over the right hip. Neurologic examination shows decreased hearing in the left ear; the Weber test localizes to the left side. Serum studies show an alkaline phosphatase concentration of 410 U/L, calcium concentration of 9.5 mg/dL, and parathyroid hormone level of 322 pg/mL. An x-ray of the spine shows a fracture of the L4 vertebra. Which of the following is the most likely diagnosis?", "answer": "Osteitis deformans", "options": {"A": "Osteoporosis", "B": "Osteomalacia", "C": "Osteitis deformans", "D": "Osteonecrosis", "E": "Osteopetrosis"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A study investigating the use of adalimumab for the relief of peripheral arthropathy in patients with psoriatic arthritis was conducted. The study utilizes a crossover design in which half of the study participants are given adalimumab for a month while the other half takes placebo. After a 2 week washout period in which no one takes any adalimumab, the group that was originally on adalimumab is given placebo for a month while the group that was originally taking placebo is given adalimumab for a month. Pain in all affected joints is assessed clinically by follow-up visits every two weeks for the duration of the study. Which of the following is true about cross-over study designs?", "answer": "1 and 2", "options": {"A": "Crossover studies avoid the ethical issue of not giving all participants access to a novel therapeutic agent", "B": "Crossover studies minimize the effects of differences between participants", "C": "The purpose of the washout period is to increase the length of the study to gather more data", "D": "1 and 2", "E": "2 and 3"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 64-year-old woman presented to the community health clinic complaining of nausea, bloating, pain in both knees, and a burning sensation in her feet. She has recently immigrated to the United States and was previously diagnosed with diabetes mellitus, hypertension, and osteoarthritis but no medical records are currently available. She has stopped taking her medication since immigrating; however, she does recall being on insulin but cannot recall the dosage or the specific type. She has a blood pressure of 172/120 mm Hg, heart rate of 95/min, respiratory rate of 15/min, and temperature of 37.0°C (98.6°F). Her random serum glucose is 364 mg/dL. She is started on atorvastatin, amlodipine, ramipril, aspirin, duloxetine, metoclopramide, acetaminophen, and insulin detemir. Three weeks later, she presents with generalized weakness, walking difficulty, and hand tremors. Physical examination reveals bilateral hand tremors, cogwheel rigidity, and bradykinesia. She is walking with small narrow steps and reduced arm swing. Today her random serum glucose is 150 mg/dL. Her symptoms are presumed to be caused by a drug. Which medication is likely responsible for these symptoms?", "answer": "Metoclopramide", "options": {"A": "Atorvastatin", "B": "Duloxetine", "C": "Metoclopramide", "D": "Ramipril", "E": "Acetaminophen"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 51-year-old man presents to the emergency room after being the victim of a robbery and assault. He was walking down an alley when he was approached by a stranger with a knife. Upon resisting, the stranger stabbed the patient’s right distal forearm before stealing his wallet and evading the scene. The patient was able to call an ambulance and has remained conscious despite mild bleeding from the injury site. He reports severe pain in his forearm and an inability to move his 2nd and 3rd fingers. He has no medical conditions and takes no medications. He is allergic to penicillin and ibuprofen. On exam, the patient is able to flex the proximal interphalangeal (PIP) joints of his 2nd through 5th fingers. When the PIP joints of his 2nd through 5th fingers are restrained by the examiner, flexion is noted at the DIP joints of the 4th and 5th fingers but not the 2nd and 3rd digits. Thumb flexion at the metacarpophalangeal (MCP) joint and interphalangeal (IP) joint is preserved. Sensation is intact over the palmar and dorsal aspects of the radial and ulnar hand. This patient most likely has an injury to which of the following muscle tendons?", "answer": "Flexor digitorum profundus", "options": {"A": "Flexor digitorum brevis", "B": "Flexor digitorum longus", "C": "Flexor digitorum profundus", "D": "Flexor digitorum superficialis", "E": "Flexor pollicis longus"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "Researchers develop a drug X that acts on the loop of Henle but discover that it does not reach its intended site of action within the nephron. It is freely filtered but rapidly disappears from the proximal tubule. They modify several of the chemical properties of drug X to produce drug Y, which cannot be reabsorbed from the proximal tubule. Which of the following natural substances are most similar to the concentration profiles of drug X and drug Y in the proximal tubule?", "answer": "Drug X: glucose; Drug Y: creatinine", "options": {"A": "Drug X: creatinine; Drug Y: glucose", "B": "Drug X: glucose; Drug Y: creatinine", "C": "Drug X: glucose; Drug Y: potassium", "D": "Drug X: potassium; Drug Y: creatinine", "E": "Drug X: creatinine; Drug Y: potassium"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 66-year-old woman comes to the emergency department because of fever and difficulty swallowing for 5 hours. She appears anxious. Her temperature is 39.1°C (102.4°F). Physical examination shows an extended neck and excessive drooling. Her voice is muffled and there is inspiratory stridor. There is tender bilateral cervical lymphadenopathy and pain upon palpation of the hyoid. Laboratory studies show a leukocyte count of 18,800/mm3 with 85% neutrophils. Which of the following is the most likely causal organism?", "answer": "Haemophilus influenzae type b", "options": {"A": "Haemophilus influenzae type b", "B": "Streptococcus pyogenes", "C": "Adenovirus", "D": "Corynebacterium diphtheriae", "E": "Parainfluenza virus\n\""}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 65-year-old man with a history of coronary artery disease presents to your office complaining of ongoing chest pain with exertion. The patient has had a recent cardiac work-up that showed no areas of acute ischemia. At the last visit, the patient was prescribed sublingual nitroglycerin for symptom relief of stable angina. On further questioning, the patient states that he has been swallowing the tablet whole instead of allowing it to dissolve because he “does not like the taste”. What is the cause of the persistent symptoms?", "answer": "First pass metabolism of nitroglycerin", "options": {"A": "Coronary steal syndrome", "B": "Nitroglycerin tolerance", "C": "Unstable angina", "D": "First pass metabolism of nitroglycerin", "E": "Concomitant use of sildenafil"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 5-year-old boy is brought to the physician by his mother because of a 3-day history of low-grade fever and sore throat. This morning, she noticed a rash on his buttocks, hands, and feet. He does not have pruritus. His temperature is 38.3°C (100.9°F), pulse is 99/min, and blood pressure is 123/78 mm Hg. Physical examination shows oral vesicles. A photograph of the rash on the feet is shown. Which of the following is the most likely pathogen?", "answer": "Coxsackie A virus", "options": {"A": "Herpes simplex virus 1", "B": "Varizella zoster virus", "C": "Coxsackie A virus", "D": "Parvovirus B19", "E": "Epstein-Barr virus"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "An 8-year-old African-American male is found to have a holosystolic, harsh-sounding murmur upon physical examination. The murmur is best appreciated at the left sternal border, and is found to be louder when the patient squats. Which of the following is the most likely diagnosis?", "answer": "Ventricular septal defect", "options": {"A": "Ventricular septal defect", "B": "Patent ductus arteriosus", "C": "Atrial septal defect", "D": "Tricuspid atresia", "E": "Aortic stenosis"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 29-year-old G1P0 woman at 32 weeks of gestation comes to the emergency department complaining of vaginal bleeding for the past hour. She noticed some blood on the toilet paper when she went to the bathroom an hour ago, but now she is bleeding through her underwear. She denies any trauma, pain, abnormal discharge or odor, fever, or recent infections. The patient mentioned that that during her last ultrasound, the doctor told her that, “there’s an abnormality but not to worry,” but she can’t remember the name of the condition. Her temperature is 100.1°F (37.8°C), blood pressure is 120/70 mmHg, pulse is 86/min, and respirations are 15/min . A fetal heart tracing is obtained and shows a fetal heart rate of 130-140, long-term variability, and appropriate accelerations. What is the most likely explanation for this patient’s presentation?", "answer": "Attachment of the placenta to the lower placental segment over the internal os", "options": {"A": "Abnormal placental spiral artery development", "B": "Attachment of the placenta to the lower placental segment over the internal os", "C": "Cystic swelling of chorionic villi and trophoblast proliferation", "D": "Fetal vessels in close proximity to the cervical os", "E": "Premature separation of placenta from the uterine wall"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 55-year-old woman comes to the office complaining of a dry mouth for the past few months. She has to drink water more frequently, as she finds it difficult to chew and swallow solid foods. She has to wake up 3–5 times each night to drink due to intense thirst. She also complains of a foreign body sensation in both the eyes for the past month. She has had no joint pain, fever, weight loss, or urinary or bowel changes. She does not smoke cigarettes but drinks alcohol socially. Her mother has rheumatoid arthritis for which she takes methotrexate, and her father died of prostatic carcinoma 7 years ago. Her temperature is 36.7°C (98°F), blood pressure is 130/75 mm Hg, pulse is 80/min, respirations are 14/min, and BMI is 28 kg/m2. On examination, the eyes and oral cavity appear dry, and dental caries are present. No lymphadenopathy is noted. Cardiopulmonary and abdominal examinations are negative. Laboratory results are shown below:\nComplete blood count:\nHemoglobin 10 g/dL\nLeukocytes   13,500/mm3\nPlatelets 170,000/mm3\nESR 65 mm/hr\n   Antinuclear antibody Positive\nRheumatoid factor Positive\nAnti dsDNA Negative\nAnti Ro Positive\nAnti-CCP Negative\nAnti Jo 1   Negative\nWhich of the following is the most likely diagnosis?", "answer": "Primary Sjogren’s syndrome", "options": {"A": "Rheumatoid arthritis", "B": "Systemic lupus erythematosus", "C": "Primary Sjogren’s syndrome", "D": "Polymyositis", "E": "Secondary Sjogren’s syndrome"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 42-year-old woman presents to the physician with chronic abdominal pain. She was initially diagnosed with an ulcer in the 2nd part of the duodenum and severe esophagitis 6 years ago. Despite confirmed H. pylori eradication and long-term therapy with pantoprazole, she has had frequent recurrences of duodenal and gastric ulcers. The medical history is otherwise unremarkable. She is a 10 pack-year smoker and consumes alcohol regularly. Her father had severe gastric ulcer disease. The vital signs are within normal limits. The body mass index is 19 kg/m2. Mild epigastric tenderness is noted on deep palpation of the epigastrium. The laboratory studies show the following:\nLaboratory test\nHemoglobin 10 g/dL\nMean corpuscular volume 75 μm3\nLeukocyte count 7500/mm3 with a normal differential\nSerum  \nNa+ 145 mEq/L\nK+ 4.5 mEq/L\nCa+ 9.5 mg/dL\nPhosphorus 4 mg/dL\nUrea nitrogen 18 mg/dL\nCreatinine 1.0 mg/dL\nWhich of the following is the most likely underlying cause of this patient’s condition?", "answer": "Gastrin-secreting tumor", "options": {"A": "Chronic alcohol consumption", "B": "Gastrin-secreting tumor", "C": "Primary hyperparathyroidism", "D": "Tobacco use", "E": "Non-disclosed ibuprofen use"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 33-year-old woman comes to the emergency department for severe abdominal pain for the past hour. The pain is 10/10, stabbing, and concentrated around the epigastric region with radiation to the back. She had 2 episodes of emesis and complains of nausea. She has had multiple similar episodes over the past 3 months which are not correlated with oral intake. She denies fever, weight changes, headaches, palpitations, bowel changes, or chest pain, but endorses nausea and stool that is hard to flush. Her medical history is significant for diabetes that is controlled with metformin. Her surgical history is significant for an elective cesarean section 5 years ago. She is currently sexually active with contraceptive use. What imaging finding would you expect in this patient?", "answer": "Multiple pancreatic calcifications on CT", "options": {"A": "Gallbladder thickening and presence of cholelithiasis on ultrasound", "B": "Increase in appendicular diameter and fat stranding on computer tomography (CT)", "C": "Lack of an intrauterine pregnancy on ultrasound", "D": "Multiple air-fluid levels on upright abdominal radiograph", "E": "Multiple pancreatic calcifications on CT"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 37-year-old female presents to her primary care provider for a normal follow-up visit. Her past medical history is notable for poorly controlled type II diabetes mellitus despite good treatment adherence to oral medications. She has been trialed on metformin and glyburide but stopped them due to rapid weight gain, respectively. She was started on a new oral diabetes medication three months ago. Since starting the new medication, she has noticed slowly progressive swelling in her lower extremities. Her temperature is 99.2°F (37.3°C), blood pressure is 120/75 mmHg, pulse is 105/min, and respirations are 22/min. She has gained 10 pounds since her last visit. Physical examination reveals 1+ pitting edema in the bilateral legs. A hemoglobin A1c lab test is drawn. This patient’s symptoms are most likely attributable to which of the following medications?", "answer": "Pioglitazone", "options": {"A": "Glipizide", "B": "Exenatide", "C": "Pioglitazone", "D": "Pramlintide", "E": "Acarbose"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 21-year-old woman comes to the physician for a follow-up examination. Four months ago, she underwent posterior arthrodesis for thoracolumbar scoliosis. She has recovered well from the surgery but noticed difficulties combing her hair with her right hand. A photograph of the patient's back is shown. The nerve that was most likely injured in the surgery originates from which of the following spinal roots?", "answer": "C5–C7", "options": {"A": "C6-C8", "B": "C1-C3", "C": "C3-C5", "D": "T2-T5", "E": "C5–C7"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 45-year-old female is brought by ambulance to your emergency room after complaining of shortness of breath along with profuse sweating at a company social function. Her vitals were notable for elevated blood pressure with a normal exam and a stable electrocardiogram. She has been seeing a psychiatrist recently for her depression and was prescribed phenelzine after failing treatment with a first-line antidepressant therapy. What must she have been exposed to at the party that led to such a dramatic side effect?", "answer": "Tyramine", "options": {"A": "Norepinephrine", "B": "Tryptophan", "C": "Tyramine", "D": "Gluten", "E": "Dopamine"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 3-day-old female infant is brought by her mother to the pediatrician’s office. The patient’s mother says she has been noticing bruising on her child’s arms and some blood in her diapers. The infant was born at home after the mother received normal prenatal care. The patient has been exclusively breastfed since birth and is gaining weight appropriately. On exam, multiple ecchymoses are noted throughout the patient’s torso and extremities. The patient is lethargic with a large, full anterior fontanelle. On examination of the diaper, some dried blood mixed with a small amount of stool is noted. Which of the following would most likely be expected for this patient's prothrombin time (PT), partial thromboplastin time (PTT), and bleeding time?", "answer": "PT increased, aPTT normal, bleeding time normal", "options": {"A": "PT normal, aPTT normal, bleeding time normal", "B": "PT increased, aPTT normal, bleeding time normal", "C": "PT increased, aPTT increased, bleeding time increased", "D": "PT normal, aPTT normal, bleeding time increased", "E": "PT normal, aPTT increased, bleeding time normal"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 53-year-old woman comes to see her primary care physician because she has had fever and malaise for two days. She was in her usual state of health until three days ago when she began to feel tired in the evening and decided to go to bed early. The next day she developed a fever, productive cough, chills, and malaise. She is otherwise healthy with no chronic conditions and lives by herself with two cats. She smokes one pack of cigarettes per day and drinks alcohol socially. On physical exam, she is found to have increased dullness to percussion at the lung bases and blood work is obtained showing elevated levels of C-reactive protein and hepcidin. The signal responsible for the elevated levels of these proteins was most likely secreted by which of the following cells?", "answer": "Macrophages", "options": {"A": "Macrophages", "B": "Neutrophils", "C": "Regulatory T-cells", "D": "Type 1 helper T-cells", "E": "Type 2 helper T-cells"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "Three weeks after undergoing transurethral prostate resection for benign prostatic hyperplasia, a 70-year-old man has fever, malaise, and pain in his extremities. Physical examination shows subungal petechiae and tender red papules on his fingers and toes. A new holosystolic murmur is heard on chest auscultation. A photomicrograph of a Gram stain of an isolate from blood culture is shown. The organism does not cause hemolysis on blood agar. Addition of pyrrolidonyl-β-naphthylamide gives the bacterial colonies a cherry red color. Which of the following is the most likely causal organism?", "answer": "Enterococcus faecalis", "options": {"A": "Enterococcus faecalis", "B": "Pseudomonas aeruginosa", "C": "Streptococcus gallolyticus", "D": "Cardiobacterium hominis", "E": "Staphylococcus epidermidis"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "An 85-year-old woman is brought to her primary care provider by her son for a checkup. She is feeling well with no major complaints. Her son is concerned that she has been bruising much more easily over the last week or two. Past medical history is significant for hypertension, hyperlipidemia, and a urinary tract infection that was successfully treated with an extended course of oral cephalexin 3 weeks ago. Family history is noncontributory. Today, her heart rate is 90/min, respiratory rate is 17/min, blood pressure is 125/85 mm Hg, and temperature is 36.7°C (98.1°F). On physical exam, her heart has a regular rate and rhythm and her lungs are clear to auscultation bilaterally. She has some poorly demarcated purple-yellow bruising and areas of dark purple bruising as well. Further analysis reveals a prolonged PT that corrects with mixing, normal liver function tests, and a stool test that is guaiac positive. The physician administers an injection that should improve her condition and recommends further testing and a follow-up exam. What is the mechanism of action of the medication received by the patient?", "answer": "γ-carboxylation of liver enzymes", "options": {"A": "γ-carboxylation of pancreatic enzymes", "B": "Protein C deficiency", "C": "Activation of 7-dehydrocholesterol by UV light", "D": "γ-carboxylation of liver enzymes", "E": "Parathyroid hormone elevation"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 35-year-old man presents with loose stools and left lower quadrant abdominal pain. He says he passes 8–10 loose stools per day. The volume of each bowel movement is small and appears mucoid with occasional blood. The patient reports a 20-pack-year smoking history. He also says he recently traveled abroad about 3 weeks ago to Egypt. The vital signs include: blood pressure 120/76 mm Hg, pulse 74/min, and temperature 36.5°C (97.8°F). On physical examination, mild to moderate tenderness to palpation in the left lower quadrant with no rebound or guarding is present. Rectal examination shows the presence of perianal skin ulcers. Which of the following is the most likely diagnosis in this patient?", "answer": "Amebiasis", "options": {"A": "Amebiasis", "B": "Crohn’s disease", "C": "Ulcerative colitis", "D": "Salmonellosis", "E": "Diverticulosis"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "Hepatocyte nuclear factor 4 alpha (HNF4a) is a transcription factor that is found in the liver, pancreas, kidney, and intestines. The gene is composed of 11 exons and depending on the tissue there are different isoforms of the protein being expressed. Which of the following is responsible for producing the different isoforms of HNF4a?", "answer": "Alternative splicing", "options": {"A": "Addition of 7-methylguanosine cap", "B": "Addition of polyadenylated (poly-A) tail", "C": "Alternative splicing", "D": "Histone acetylation", "E": "DNA methylation"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 50-year-old man presents for a routine examination. Past medical history is significant for cirrhosis secondary to hepatitis C virus (HCV) infection diagnosed 4 years ago and complicated by ascites. Current medications include furosemide 40 mg orally daily. Physical examination is unremarkable. Laboratory findings are significant for the following:\nLaboratory test\nAspartate Aminotransferase (AST) 80 U/L\nAlanine Aminotransferase (ALT) 50 U/L\nTotal bilirubin 2.5 mg/dL\nDirect bilirubin 1.8 mg/dL\nAlkaline phosphatase (ALP) 140 U/L\nInternational normalized ratido (INR) 1.9\nSerum creatinine 1 mg/dL\nUrinalysis\nSodium 200 mmol/24h\nPotassium 60 mmol/24h\nProtein Nil\nRBCs Nil\nRBC casts Nil\nWBCs Nil\nUrea 13 g/24h\nCreatinine 6 mmol/24h\n  Abdominal and renal ultrasound reveals no interval change over the past 6 months. Moderate ascites is present. Upper GI endoscopy reveals esophageal varices with a hepatic venous pressure gradient measuring 14 mm Hg. Diagnostic paracentesis is performed and yields a clear liquid with an absolute polymorphonuclear neutrophil (PMN) count of 75 cells/mm3. Which of the following is the most likely etiology of this patient’s condition?", "answer": "Portal hypertension", "options": {"A": "Congestive gastropathy", "B": "Hepatocellular carcinoma", "C": "Portal hypertension", "D": "Spontaneous bacterial peritonitis", "E": "Hepatorenal syndrome"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 45-year-old man with HIV comes to the physician because of multiple lesions on his lower extremity. The lesions are increasing in size and are not painful or pruritic. He does not have lymphadenopathy. He works at a garden center. He lives in Mississippi. Medications include abacavir, dolutegravir, and lamivudine. His temperature is 37.7°C (98.8°F), pulse is 75/min, and blood pressure is 125/80 mm Hg. Examination shows multiple lesions on both heels; some are elevated. There are two similar lesions on the chest. An image of the patient's right heel is shown. His CD4+ T-lymphocyte count is 450/mm3 (normal ≥ 500/mm3). A skin biopsy shows multiple spindle-shaped cells and leukocyte infiltration. Which of the following is the most likely causal organism?", "answer": "Human herpesvirus 8", "options": {"A": "Mycobacterium avium complex", "B": "Human herpesvirus 8", "C": "Bartonella henselae", "D": "Coccidioides immitis", "E": "Epstein-Barr virus"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 32-year-old woman presents to the office complaining of pain, numbness, and discoloration of her fingers over the past 6 months. She notices that cold temperatures worsen these symptoms, turning the tip of her fingers white and sometimes blue. Her vital signs show her temperature is 37.5°C (99.5°F), blood pressure is 124/86 mm Hg, pulse is 80/min, and respirations are 10/min. On physical examination, the patient has a pale malar rash spread across her face with tender cervical and axillary lymphadenopathy. Examination of her hands reveal tenderness and shiny sclerodactyly. Antinuclear and anti-U1 ribonucleoprotein antibodies are positive. A diagnosis of mixed connective tissue disease is confirmed. What is the next best step in management?", "answer": "Echocardiogram", "options": {"A": "Echocardiogram", "B": "Arthrocentesis", "C": "Bone marrow transplant", "D": "Upper GI series", "E": "Lymph node biopsy"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 58-year-old woman presents with difficulty moving her right shoulder. She underwent a right radical mastectomy with lymph node dissection 3 weeks ago. Her surgery went well with no complications. She has undergone some physical therapy which has not been effective. A few days ago, she started to notice brief periods of painful shoulder instability, especially while opening or closing doors. On physical examination, there is normal active and passive range of motion in the right shoulder. Strength is 5 out of 5 in all muscles of the right shoulder and upper extremity. Sensation is intact. When the patient is asked to push against the wall, her right shoulder blade moves backward (see image). Which of the following nerves is most likely injured in this patient?", "answer": "Long thoracic nerve", "options": {"A": "Axillary nerve", "B": "Suprascapular nerve", "C": "Radial nerve", "D": "Long thoracic nerve", "E": "Ulnar nerve"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 40-year-old man comes to the physician because he is concerned about the amount of breast tissue he has recently developed. His wife has noticed that he has been irritable for the past month. He was recently treated for tinea capitis. In preparation for an upcoming bodybuilding competition, he has been eating a lot of chicken breast. He drinks 2 beers everyday. He smokes marijuana 3–4 times a week but does not smoke cigarettes. He weighs 90 kg (198 lb) and is 175 cm (5 ft 8 in) tall; BMI is 30.1 kg/m2. Physical examination shows bilateral gynecomastia and small, firm testes. There is no hepatosplenomegaly or abdominal tenderness. Laboratory studies show:\nHematocrit 60%\nPlatelet count 400,000/mm3\nSerum\nNa+ 135 mEq/L\nCl- 97 mEq/L\nK+ 4.5 mEq/L\nHCO3- 25 mEq/L\nGlucose 100 mg/dL\nWhich of the following is the most likely cause of his symptoms?\"", "answer": "Anabolic steroid use", "options": {"A": "Side effect of tinea capitis treatment", "B": "Anabolic steroid use", "C": "Normal aging", "D": "Erythropoietin use", "E": "Marijuana use"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 35-year-old woodsman from local forestry presents to a clinic for counseling regarding his contact with a wild fox that occurred 5 days ago. He says that the fox was not aggressive, allowed him to caress it, and even licked his forearm where he had an open wound. Two days ago, in the same forest, foresters shot a group of foxes who had attacked them, and the fox corpses were handed over to a local veterinary laboratory for testing. Two locals also reported they were attacked by foxes, so the patient became concerned about his exposure. At the time of presentation, the patient had no complaints. His vital signs are as follows: the blood pressure is 125/80 mmHg, the heart rate is 81/min, the respiratory rate is 14/min, and the temperature is 36.8°C (98.2°F). Physical examination reveals 2 healing lacerations, 2 × 3 cm, with a depth of 1 mm each, and multiple scratches on the flexor surface of his right arm. The patient is unaware of his immunization status. Which of the following statements is correct?", "answer": "If rabies immunoglobulin is not available immediately, it can be administered within 7 days of the first vaccine dose.", "options": {"A": "The patient does not need immunoglobulin to be administered since he was not bitten by the animal.", "B": "Before initiating post-exposure prophylaxis, results of laboratory testing of the fox's corpses should be obtained.", "C": "There is no need to treat the patient’s wounds before administering post-exposure prophylaxis because the wounds are already healing; thus, they do not pose a threat to the patient’s health.", "D": "If rabies immunoglobulin is not available immediately, it can be administered within 7 days of the first vaccine dose.", "E": "The patient should be isolated for the whole duration of post-exposure prophylaxis measures."}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 14-year-old boy presents to his primary care physician for a general check up. The patient's parents refuse to allow the boy to join the school basketball team. The patient has attended two practices, and both times during conditioning, he has fainted. Otherwise, the child is performing well in school. The patient has a past medical history of obesity, elevated fasting blood glucose, and high blood pressure. He is not currently taking any medications. The patient's parents want the patient to be cleared medically before he goes back to playing basketball again. His temperature is 99.5°F (37.5°C), blood pressure is 130/87 mmHg, pulse is 81/min, and respirations are 11/min. Physical exam is notable for an obese child who is pleasant and conversational. Pulmonary exam reveals lungs that are clear to auscultation bilaterally. Cardiovascular exam reveals a murmur heard loudest along the left sternal border. Neurological exam reveals 5/5 strength in the upper and lower extremities with 2+ reflexes. Further diagnostic exams are ordered. Which of the following is appropriate management in this patient?", "answer": "Metoprolol", "options": {"A": "Metformin", "B": "Metoprolol", "C": "Hydrochlorothiazide", "D": "Suggest the patient exercise more before joining a competitive team", "E": "Clear the patient to participate in sports"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 65-year-old man with chronic obstructive pulmonary disease is admitted to the hospital for the treatment of worsening shortness of breath and productive cough. Three days later, he complains of weakness in the lower limbs. His muscle strength is 4/5 at both hips but normal elsewhere. The drug that is most likely responsible for this patient's muscle weakness inhibits which of the following?", "answer": "Nuclear factor-κB", "options": {"A": "Adenosine receptor", "B": "5-lipoxygenase", "C": "Myosin light-chain kinase", "D": "Nuclear factor-κB", "E": "Phospholipase C"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 64-year-old woman is brought to the emergency department after a syncopal episode 2 hours ago while grocery shopping. She has been feeling fatigued and lightheaded for the past couple of days. She has hypertension. Current medications include carvedilol. She appears diaphoretic. She is oriented to person but not to place or time. Her blood pressure is 102/65 mm Hg. An ECG is shown. Which of the following is the most appropriate next step in management?", "answer": "Placement of transcutaneous pacemaker", "options": {"A": "Observation", "B": "Adminstration of epinephrine", "C": "Administration of dopamine", "D": "Placement of transcutaneous pacemaker", "E": "Administration of amiodarone\n\""}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 42-year-old morbidly obese woman presents to the emergency room for evaluation of a rash that started 3 days ago. The rash appeared under the patient’s breasts as well as in the abdominal folds, and the patient describes it as being very itchy. The rash is bright red with scaling and a few scattered purulent areas of skin breakdown. The patient is afebrile and is in no apparent distress, besides being uncomfortable from the itching. What is the most likely causative agent of this rash?", "answer": "A commensal yeast that is catalase-positive", "options": {"A": "A heavily encapsulated, urease-positive yeast", "B": "A gram-negative rod that produces pyocyanin", "C": "An irregular, non-septate yeast with wide angles", "D": "An acid-fast bacillus", "E": "A commensal yeast that is catalase-positive"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 47-year-old man comes to the physician because of severe retrosternal chest pain and shortness of breath for 45 minutes. He has dyslipidemia, hypertension, and type 2 diabetes mellitus. Current medications include hydrochlorothiazide, lisinopril, metformin, and atorvastatin. He has smoked 1 pack of cigarettes daily for 20 years. He appears pale and diaphoretic. His temperature is 37°C (98.6°F), pulse is 115/min, and blood pressure is 140/70 mm Hg. Breath sounds are normal. The remainder of the examination shows no abnormalities. An ECG shows left ventricular hypertrophy with ST-segment elevation in leads I, aVL, and V1–V6. High-dose aspirin, clopidogrel, metoprolol, sublingual nitroglycerin, and unfractionated heparin are administered. As the patient awaits transport to the nearest emergency room, he collapses and becomes unresponsive. His pulse and blood pressure cannot be detected. Despite resuscitative efforts, the patient dies. Which of the following is the most likely cause of death in this patient?", "answer": "Ventricular fibrillation", "options": {"A": "Papillary muscle rupture", "B": "Left ventricular failure", "C": "Ventricular fibrillation", "D": "Septal wall rupture", "E": "Pulmonary embolism\n\""}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 4-year-old boy presents to a clinic with intermittent fevers and a rash for 6 days. According to his mother, he is also complaining of pain all over his body. She adds that the rash 1st appeared on his face within 12 hours of the onset of fever, and later spread to his trunks and limbs. The patient denies any itchiness over the rash. There is no history of a sore throat or recent use of medication for symptom relief. The temperature is 37.2°C (99.9°F) and the pulse is 88/min. On examination, there is a maculopapular rash on the face and the trunk, including the limbs, but sparing the palms and soles. The pediatrician reassures the mother that this is most likely a viral infection and will resolve spontaneously. After 7–10 days, the boy is brought back to the clinic for a follow-up visit. The areas affected by the rash appear to have a central clearing giving a lacy or reticular appearance, especially on the cheeks and it looks like someone slapped him on the cheeks. Immunoglobulin M (IgM) antibody detection by the enzyme-linked immunoassay (ELISA) will most likely detect antibodies against which of the following pathogens?", "answer": "Parvovirus B19", "options": {"A": "Streptococcus pyogenes", "B": "Measles virus", "C": "Human herpesvirus 6", "D": "Rubella virus", "E": "Parvovirus B19"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 25-year-old woman comes into your office with complaints of heavy bleeding. She states that her mother also has heavy bleeding during her menstrual cycle. She has had a heavy flow as long as she can remember and had her first menstrual cycle at age 12. She states during her cycle, she has to change pads every 2 hours for at least 3 days. She also states that she gets bruised easily just like her mother. She denies any past medical history other than her heavy menstrual flow and denies taking any medications. She also denies any medical history in her father and says he is \"perfectly healthy.\" Her vitals are HR 85, T 98.8 F, RR 13, BP 125/75. Her CBC is significant for Hgb 10.5, WBC 5.8, Plts 250, Hct 33. On coagulation studies, her PT is 14 seconds and her PTT is 43 seconds. Her INR is 1.1. What is the most likely cause of this patient's menorrhagia?", "answer": "Von Willebrand's disease", "options": {"A": "Factor V Leiden", "B": "Von Willebrand's disease", "C": "Hemophilia A", "D": "Hemophilia B", "E": "Antiphospholipid antibody syndrome"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 30-year-old woman comes to the physician because of numbness, fatigue, and blurry vision for 1 week. The symptoms are worse after a hot shower or bath. She had an episode of right arm weakness 2 years ago that resolved without intervention. She recently returned from a hiking trip in upstate New York. Her temperature is 37.1°C (100°F) and blood pressure is 100/66 mm Hg. Physical examination shows decreased sensation to light touch in the left hand, right thigh, and right flank. Strength is normal. There is left-sided photophobia and pupillary constriction in the left eye is decreased compared to the right eye. Which of the following best describes the pathogenesis of the disease process in this patient?", "answer": "Th1 cell-mediated nerve sheath damage", "options": {"A": "Spirochete protein cross-reactivity in the meninges", "B": "Osmotically-mediated Schwann cell damage", "C": "Th1 cell-mediated nerve sheath damage", "D": "Immune complex deposition in the arterial endothelium", "E": "Lymphocytic infiltrate of the endoneurium"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 30-year-old man visits his physician with thoughts that he ‘is not real’ which occurred suddenly and have persisted for weeks. The patient states that, 3 weeks ago, he witnessed an armed robbery in which he saw a person get shot in the chest. The patient states that at the time the shot was fired, he felt as though he ‘wasn’t in the room’ and as if he was ‘floating above watching it all happen’ below him. Ever since the event, he has been having similar experiences without provocation. He states that now, seemingly out of nowhere, he will have a sudden feeling that he is ‘perceiving life as a dream’. He now seeks help to control these feelings of depersonalization. Which of the following would be the best course of treatment for this patient?", "answer": "Psychotherapy", "options": {"A": "Amantadine", "B": "Butorphanol", "C": "Ketamine", "D": "Dextromethorphan", "E": "Psychotherapy"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 9-year-old boy presents with recent onset worsening performance in school and facial lesions that look like acne. Past medical history is significant for developmental delays and infantile spasm. No current medications. On physical examination, there are facial papulonodular lesions (as shown in the image), pitting of dental enamel, and multiple hypomelanotic oval macules over the torso. Which of the following genes is most likely impaired in this patient?", "answer": "TSC", "options": {"A": "VHL", "B": "TSC", "C": "NF1", "D": "NF2", "E": "GNAQ"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 14-year-old girl is brought to the emergency department because of occipital headache, nausea, and vomiting for the last 2 hours. She has a multi-year history of frequent left ear infections and discharge, with poor response to antimicrobial therapy. She has muffled hearing in the left ear. Her blood pressure is 134/78 mm Hg, the pulse is 83/min, the respiratory rate is 16/min, and the temperature is 36.5°C (97.7°F). She is alert and oriented. Physical examination of the left ear shows perforation of the tympanic membrane, granulation tissue, and white keratinaceous debris in the posterosuperior quadrant of the tympanic membrane. An MRI shows evidence of sigmoid sinus thrombosis on the left side and a hyperintense area in the middle ear on. Which of the following is the most likely underlying cause of this patient’s current condition?", "answer": "Cholesteatoma", "options": {"A": "Acoustic neuroma", "B": "Cholesteatoma", "C": "Chronic serous otitis media", "D": "Chronic suppurative otitis media", "E": "Meningioma"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "An otherwise healthy 8-year-old boy is brought to the emergency department by his mother 2 hours after the sudden onset of scrotal pain. Physical examination shows nontender testes and a tender, 5-mm, bluish nodule at the superior pole of the left testis. The patient undergoes urgent surgical exploration of the scrotum. During the operation, the nodule on the superior pole of the testis is found to be necrotic. In the process of embryologic development, this nodule forms as a result of the activity of which of the following?", "answer": "Sertoli cells", "options": {"A": "Leydig cells", "B": "Estradiol", "C": "5-alpha reductase", "D": "Luteinizing hormone", "E": "Sertoli cells"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 23-year-old woman comes to the physician for a 6-month history of dry cough, hoarseness, and chest pain. She does not smoke and has not lost weight. Laboratory studies show no abnormalities. An x-ray of the chest shows a mass that projects across the right hilum. A CT scan of the chest is shown. Which of the following is the most likely diagnosis?", "answer": "Neurofibroma", "options": {"A": "Rhabdomyosarcoma", "B": "Neurofibroma", "C": "Sarcoma", "D": "Aortic aneurysm", "E": "Lymphoma"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 4-year-old is brought into the emeregency room by his mother. The mother states that the child had a slight cough one week ago that has since worsened. The mother states the child's cough sounds like someone barking and states that he has also had mild fevers along with rhinorrhea. The patient's vitals are significant for a fever of 100.8 F, and his physical exam reveals inspiratory stridor. What is the most likely organism responsible?", "answer": "Parainfluenza virus", "options": {"A": "Parainfluenza virus", "B": "Respiratory syncytial virus", "C": "Adenovirus", "D": "Ebstein barr virus", "E": "Influenza A virus"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A researcher interested in the relationship between vaccination and autism sends a survey to parents of children who are active patients at a large primary care practice. The survey asks several questions, including whether their children received their childhood vaccines on-time, and whether their children currently have a diagnosis of an autism spectrum disorder. Which of the following correctly identifies the study design used by the researcher?", "answer": "Cross-sectional", "options": {"A": "Cross-sectional", "B": "Case-crossover", "C": "Cohort", "D": "Randomized controlled trial", "E": "Case-control"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 6-month-old boy is brought to the physician for a well-child examination. He was born at term, and pregnancy was complicated by prolonged labor. There is no family history of serious illness. He can sit upright without support and can roll over from the prone to the supine position. He cannot pull himself to stand. He can grasp his rattle and cannot transfer it from one hand to the other. He babbles. He cries if anyone apart from his parents holds him or plays with him. He touches his own reflection in the mirror. Vital signs are within normal limits. He is at 40th percentile for head circumference, 30th percentile for length and at 40th percentile for weight. Physical examination shows no abnormalities. Which of the following developmental milestones is delayed in this infant?", "answer": "Fine motor", "options": {"A": "Fine motor", "B": "Social", "C": "Language", "D": "Gross motor", "E": "Cognitive"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 28-year-old woman is admitted to the hospital for treatment of a displaced fracture of the femoral neck following a high-speed motor vehicle collision. She is given pentazocine for pain relief. This drug binds to heptahelical transmembrane receptors. Which of the following is the most likely effect of this drug?", "answer": "Opening of postsynaptic K+ channels", "options": {"A": "Release of presynaptic acetylcholine", "B": "Opening of presynaptic Ca2+ channels", "C": "Release of presynaptic norepinephrine", "D": "Opening of postsynaptic Na+ channels", "E": "Opening of postsynaptic K+ channels"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 70-year-old man comes to the physician because of fatigue and intermittent epigastric pain. The symptoms began about one year ago. He describes the pain as diffuse and 3 out of 10 in intensity. Recently, he has had unusually large black stools. He appears pale. His pulse is 72/min and his blood pressure is 110/70 mm Hg. Physical examination shows epigastric tenderness. A urea breath test is positive. Upper gastrointestinal endoscopy reveals an ulcerating mass in the gastric antrum. Biopsies of the mass show diffuse infiltrates of small lymphoid cells that are positive for CD20 antigen. A CT scan of the chest and abdomen shows normal regional lymph nodes. Which of the following is the most appropriate therapy with curative intent at this time?", "answer": "Amoxicillin, clarithromycin, and omeprazole", "options": {"A": "Distal gastrectomy with gastrojejunostomy", "B": "Rituximab, cyclophosphamide, adriamycin, and vincristine", "C": "Imatinib", "D": "External beam radiation therapy", "E": "Amoxicillin, clarithromycin, and omeprazole"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 42-year-old woman approaches your office complaining of a 1-year long persistent dysuria, increasing discomfort with bladder filling and voiding, and suprapubic pain. She further comments that she has been presenting with abdominal cramps, and alternating periods of diarrhea and constipation for the past 4 months. Her family medical history is negative for malignancies and hereditary disorders. Her personal history is relevant for various visits to the general practitioners for similar complaints that resulted in multiple antimicrobial treatments for urinary tract infection. At the moment, she is not taking any medication. Physical examination shows suprapubic tenderness as well as tender areas in the pelvic floor. The vital signs include: temperature 37.0°C (98.6°F), heart rate 68/min, blood pressure 120/58 mm Hg, and respiratory rate 13/min. Vaginal examination is normal. No adnexal masses are detected and no vaginal secretions are noticed.\nShe brings a urinalysis and a urine culture from 1 week ago that show the following:\nTest Result Normal Range\nUrine culture Negative < 100,000 CFU/mL to no bacterial growth in asymptomatic patients\nUrinalysis Density: 1.030; Leukocyte esterase (-); Nitrites (-); pH: 6.0, Presence of 4 RBCs per high power field. Density: 1.030 - 1.060; Leukocyte esterase (-), Nitrites (-), pH: 4.5 - 8.0\nWhat is the most appropriate step in this case?", "answer": "Self-care and behavior modification", "options": {"A": "Self-care and behavior modification", "B": "Admission to the ER for intravenous antibiotic administration", "C": "Urinary analgesia with phenazopyridine", "D": "Conjugated estrogens", "E": "Escalation to levofloxacin"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 27-year-old man comes to the physician for a routine health maintenance examination. He says he feels well, but is worried because his 32-year-old brother recently had to start hemodialysis because of kidney disease. He reports that his grandfather had \"\"bad kidneys” as well. The patient does not have dysuria, hematuria, or flank pain. He has no history of serious illness. His vital signs are within normal limits. Physical examination shows no abnormalities. An ultrasound of his right kidney is shown. Which of the following is the most appropriate next step in management?\"", "answer": "Reassurance", "options": {"A": "Percutaneous aspiration", "B": "Reassurance", "C": "Renal biopsy", "D": "Abdominal CT scan", "E": "Partial nephrectomy"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 45-year-old man is following up with his primary care doctor for follow up of his essential hypertension. This is his annual check-up, and he reports that he has been doing well since his appointment last year. He denies any negative side effects from his amlodipine or metformin. His physical examination is within normal limits, and his vital signs are all within normal limits, other than his blood pressure being 142/84 mm Hg. Which of the following best describes the mechanism of action for his blood pressure medication?", "answer": "Dihydropyridine calcium channel blockers preferentially bind to a vascular smooth muscle", "options": {"A": "Because of its negative inotropic effects, it should be avoided in patients with underlying cardiomyopathy", "B": "Dihydropyridine calcium channel blockers preferentially bind to a vascular smooth muscle", "C": "Calcium channel blockers only bind to channels on cardiac muscles", "D": "Non-dihydropyridine calcium channel blockers preferentially bind to a vascular smooth muscle", "E": "Calcium channel blockers only bind to channels on the sarcoplasmic reticulum"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 50-year-old male visits his primary care physician with skin lesions on his knees and elbows. He reports joint pain, and physical examination reveals severe swelling of the fingers on both hands. Tests for serum rheumatoid factor are negative. Which of the following pairs of adjectives most likely characterize the patient’s skin lesions:", "answer": "Silver, scaly", "options": {"A": "Honey-colored, crusting", "B": "Irregular, depigmented", "C": "Silver, scaly", "D": "Velvety, hyperpigmented", "E": "Non-blanching, hemorrhagic"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 42-year-old woman comes to the physician because of a low-grade fever and generalized fatigue for a week. During this period, she has passed decreased amounts of urine. Two months ago, she underwent a renal allograft transplant because of reflux nephropathy. There is no family history of serious illness. Her current medications include prednisone, cyclosporine, and azathioprine. Her temperature is 37.8°C (100°F), pulse is 99/min, and blood pressure is 160/94 mm Hg. Examination shows several white patches within the oral cavity. There is a well-healed surgical incision over the right lower abdomen. The remainder of the examination shows no abnormalities. Laboratory studies show:\nHemoglobin 12.1 g/dL\nLeukocyte count 6,000/mm3\nPlatelet count 156,000/mm3\nSerum\nUrea nitrogen 89 mg/dL\nGlucose 76 mg/dL\nCreatinine 3.9 mg/dL\nDonor-specific antibodies negative\nA biopsy of the allograft shows mononuclear infiltrates with tubulitis and arteritis. C4d staining is negative. Oral fluconazole is administered. Which of the following is the most appropriate next step in the management of this patient?\"", "answer": "Methylprednisolone therapy", "options": {"A": "Intravenous immunoglobulin therapy", "B": "Methylprednisolone therapy", "C": "Removal of graft", "D": "Plasmapheresis", "E": "Local graft irradiation"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 55-year-old woman is brought to your office for evaluation of 6 months of anal discomfort, vaginal pruritus, and soreness that worsened in the last several months. The past medical history is significant for hypertension and smoking. The family history is negative for malignancies. The physical examination is unremarkable, except for the presence of white, atrophic papules merging into an ulcerated plaque, with some of the white lesions extending and surrounding the anus (see image). You order biopsies of the lesions and a follow-up appointment. 2 weeks later, the histology evaluation reports hyperkeratosis, significant epidermal thinning, and plugging of infundibular follicles. Which of the following lesions is the patient at risk to develop?", "answer": "Differentiated squamous cell carcinoma (SCC)", "options": {"A": "Basal cell carcinoma (BCC)", "B": "Vulvar low-grade squamous intraepithelial lesion (LSIL)", "C": "Differentiated squamous cell carcinoma (SCC)", "D": "Vulvar high-grade squamous intraepithelial lesion (HSIL)", "E": "Bowenoid squamous cell carcinoma"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 32-year-old male presents to his primary care physician with complaints of chronic headaches that have developed and increased in frequency and severity over the last several months. Additionally, the patient has noted he has been less coordinated over the last few weeks, stumbling and tripping often when he is walking. Physical examination is significant for notably reduced hand grip strength bilaterally as well as decreased pain and temperature sensation along the upper back and down both arms to the hands. A referral to the appropriate specialist is made, and an MRI of the brain and neck is obtained. Results of the MRI are show in Figures A and B. Which of the following is the most likely diagnosis in this patient?", "answer": "Arnold-Chiari malformation type 1", "options": {"A": "Arnold-Chiari malformation type 1", "B": "Arnold-Chiari malformation type 2", "C": "Arnold-Chiari malformation type 3", "D": "Arnold-Chiari malformation type 4", "E": "Budd-Chiari syndrome"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "After hospitalization for urgent chemotherapy to treat Burkitt’s lymphoma, a 7-year-old boy develops paresthesias of the fingers, toes, and face. Blood pressure is 100/65 mm Hg, respirations are 28/min, pulse is 100/min, and temperature is 36.2°C (97.2°F). Inflating a blood pressure cuff on the boy’s arm produces carpal spasm. He has excreted 20 mL urine in the past 6 hours. Laboratory studies show the following:\nHemoglobin 15 g/dL\nLeukocyte count 6,000/mm3 with a normal differential serum\nK+ 6.5 mEq/L\nCa+ 6.6 mg/dL\nPhosphorus 5.4 mg/dL\nHCO3− 15 mEq/L\nUric acid 12 mg/dL\nUrea nitrogen 54 mg/dL\nCreatinine 3.4 mg/dL\nArterial blood gas analysis on room air:\npH 7.30\nPCO2 30 mm Hg\nO2 saturation 95%\nFebuxostat is initiated. Which of the following is the most appropriate next step in management?", "answer": "Hemodialysis", "options": {"A": "Hemodialysis", "B": "High-dose furosemide", "C": "Intravenous 0.9% saline", "D": "Sodium bicarbonate", "E": "Orotracheal intubation"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "An 84-year-old woman with an indwelling urinary catheter and a history of recurrent nephrolithiasis is brought to the emergency department from her nursing home because of increasing confusion over the past day. On arrival, she is oriented only to person. Her temperature is 38.3°C (100.9°F). Examination shows dry mucous membranes. Urine studies show:\npH 8.3\nWBC 40/hpf\nBacteria moderate\nNitrites positive\nThe urine has an ammonia odor. Which of the following is most likely to be present on this patient's urine culture?\"", "answer": "Gram-negative, oxidase-negative rods", "options": {"A": "Gram-negative, oxidase-positive rods", "B": "Gram-positive, novobiocin-resistant cocci", "C": "Gram-negative, lactose-fermenting rods", "D": "Gram-positive, gamma-hemolytic cocci", "E": "Gram-negative, oxidase-negative rods"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 28-year-old woman who was recently hired at a new company feels intense physical attraction towards her supervisor. She feels he is exceptionally kind to her and finds herself fantasizing about him during work. While talking to her co-workers, she ardently raises complaints about her supervisor and declares that she finds him to be extremely repulsive, rude, and arrogant. Which of the following ego defenses is this patient most closely exhibiting?", "answer": "Reaction formation", "options": {"A": "Denial", "B": "Isolation of affect", "C": "Reaction formation", "D": "Repression", "E": "Suppression"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "An 11-year-old boy presents to his pediatrician with his mother for a sore throat. His symptoms began approximately a few days ago after attending a birthday party with his friends. His symptoms are accompanied by nausea, vomiting, and a mild headache. He also has mild discomfort in his throat when eating food or drinking water. The patient denies rhinorrhea, conjunctivitis, cough, myalgias, or a rash. His mother said his temperature last night was 101°F (38.3°C). On physical exam, the patient has tender and enlarged anterior cervical lymph nodes. Upon oral inspection, there is pharyngeal inflammation and exudates with petechial lesions on the soft palate. Which of the following is the best next step in management?", "answer": "Rapid antigen detection test", "options": {"A": "Azithromycin", "B": "Observation", "C": "Penicillin V", "D": "Rapid antigen detection test", "E": "Throat culture"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 52-year-old male with follicular non-Hodgkin lymphoma undergoes chemotherapy. He develops suprapubic pain and hematuria. Which of the following compounds is most likely responsible for this patient's symptoms?", "answer": "Cyclophosphamide", "options": {"A": "Cyclophosphamide", "B": "Cisplatin", "C": "Mesna", "D": "Bleomycin", "E": "Carmustine"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 68-year-old man comes to the physician because of a 1-week history of difficulty with urination. Two weeks ago, he was hospitalized for treatment of a cerebrovascular accident; his symptoms began after he was discharged. His vital signs are within normal limits. Neurologic examination shows mild dysarthria, right facial droop, and right hemiparesis. Rectal examination shows a normal prostate. The patient produces 70 mL of urine for a sample. Placement of a Foley catheter yields an additional 500 mL of urine. Which of the following is the most appropriate pharmacotherapy for this patient?", "answer": "Muscarinic agonist", "options": {"A": "Alpha-1 receptor antagonist", "B": "Muscarinic agonist", "C": "Muscarinic antagonist", "D": "Alpha-1 receptor agonist", "E": "5-alpha-reductase inhibitor"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 61-year-old woman presents with painless vaginal bleeding. Patient says the bleeding has been occurring occasionally for the past 3 years. Past medical history is significant for diabetes mellitus type 2 and hypertension, both managed medically. Current medications are atorvastatin, lisinopril, hydrochlorothiazide, and metformin. Patient has not been sexually active since the death of her husband 9 years ago. Menopause occurred 8 years ago, and she denies taking hormone replacement therapy or estrogen-containing oral contraceptives. Her last Pap smear 1 year ago was normal. Vital signs are temperature 37.0℃ (98.6℉), blood pressure 130/85 mm Hg, pulse 82/min, respiratory rate 13/min, and oxygen saturation 99% on room air. BMI is 33.8 kg/m2. On physical examination, patient is alert and cooperative. Cardiac exam is normal. Lungs are clear to auscultation. Abdomen is soft and non-tender with no masses or hepatosplenomegaly. Examination of the perineum shows pale, atrophic vaginal mucosa. Speculum examination shows no vaginal or cervical lesions. The cervix is movable and non-tender. There is trace blood in the vaginal vault and mild bleeding from the cervical os. The uterus is not enlarged but softened on palpation. Adnexa is non-palpable. Which of the following is the next best diagnostic step in this patient?", "answer": "Endometrial biopsy", "options": {"A": "Transabdominal ultrasound", "B": "Hysteroscopy", "C": "Pap test", "D": "Endometrial biopsy", "E": "Pelvic MRI"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 20-year-old African American woman presents to the clinic after missing her last 2 periods. Her cycles are usually regular, occurring at 28–32 day intervals with moderate bleeding and some abdominal discomfort. She also complains of occasional diffuse and generalized headaches. She is a college student and works part-time as a bartender. The past medical history is benign. The blood pressure is 110/70 mm Hg, the pulse is 80/min, the respiratory rate is 14/min, and the temperature is 36.5°C (97.7°F). The physical examination is significant for mild breast tenderness and secretions from the nipple area. A urine pregnancy test is negative. Which of the following is the best initial step in her management?", "answer": "Serum prolactin levels", "options": {"A": "MRI of the brain", "B": "Serum prolactin levels", "C": "LH:FSH ratio", "D": "Ultrasound of the abdomen and pelvis", "E": "Dopamine agonists"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 50-year-old man comes to the physician because of an 8-month history of intermittent watery diarrhea and abdominal pain. He has had a 12-kg (26-lb) weight loss during this period. He has also had episodic pain of the ankle, wrist, and knee joints during the past 5 years. An endoscopy with small bowel biopsy is performed. Histopathologic examination of a tissue specimen shows foamy macrophages in the lamina propria with periodic acid-Schiff (PAS)-positive inclusions. Further evaluation is most likely to show which of the following?", "answer": "Intracellular, gram-positive bacilli", "options": {"A": "Anti-tissue transglutaminase antibodies", "B": "Anti-cyclic citrullinated peptide antibody", "C": "Anti-saccharomyces cerevisiae antibodies", "D": "Intracellular, gram-positive bacilli", "E": "Low serum TSH and high free T4 concentrations"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 49-year-old woman comes to the physician because of a growing lump in the right breast that she first noticed 1 month ago. Physical examination of the right breast shows a 3.5-cm firm, fixed mass in the right upper quadrant. There is dimpling of the overlying skin. A mammogram shows a mass with poorly-defined margins and microcalcifications. Immunohistochemical analysis of a biopsy specimen from the mass shows malignant cells that stain negative for estrogen and progesterone receptors and positive for human epidermal growth factor receptor 2. The drug that most specifically targets this patient's tumor is also used in the treatment of which of the following conditions?", "answer": "Gastric cancer", "options": {"A": "Multiple sclerosis", "B": "Gastric cancer", "C": "Endometrial cancer", "D": "Osteoporosis", "E": "Rheumatoid arthritis"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 17-year-old girl is brought to the physician because her mother is concerned about her lack of appetite. She has had a 4-kg (8.8-lb) weight loss over the past 4 months. The patient states that she does not “feel like eating so much”. Over the last year her academic performance in school has decreased and she has had a lot of disputes with her parents concerning her future. Her mother says that she has also become more nervous and restless. Her grandmother had a problem with her thyroid. She is sexually active with two male partners and uses condoms inconsistently. She is at 60th percentile for height and at 15th percentile for weight. She appears thin. Her temperature is 37°C (98.6°F), pulse is 104/min, and blood pressure is 135/80 mm Hg. The pupils are 9 mm large, round and minimally reactive to light. Deep tendon reflexes are 2+ bilaterally. There is fine tremor of her hands. The remainder of the examination shows no abnormalities. Which of the following is the most appropriate next step in diagnosis?", "answer": "Obtain toxicology screening", "options": {"A": "Measure serum electrolytes", "B": "Perform abdominal ultrasound", "C": "Obtain toxicology screening", "D": "Obtain MRI of the brain", "E": "Obtain HIV screening test"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "An 11-year-old male presents to the pediatrician to be evaluated for learning difficulties. His parents report that the patient’s grades have been falling since he started middle school this year. The patient previously attended a smaller elementary school that focused more on the arts and creative play. His parents report that at home the patient bathes and dresses himself independently but requires help with more difficult tasks, such as packing his backpack and making a schedule for homework. He enjoys reading comic books and playing video games. The patient’s parents report that he said his first word at 19 months and walked at 21 months. His mother notes that she herself struggled to pay attention in her classes and completed college in six years after taking a reduced course load. On physical exam, the patient has a long, narrow face with large ears. His testicles are larger than expected for his age. Which of the following additional findings is most likely to be found in this patient’s history?", "answer": "Poor reciprocal emotional behavior", "options": {"A": "Compulsive completion of rituals", "B": "Cruelty to animals or fire-setting", "C": "Difficulty seeing the board at school", "D": "Persistent bedwetting at night", "E": "Poor reciprocal emotional behavior"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 17-year-old girl comes to the primary care clinic with her father complaining of right knee pain. She reports that the pain started about a month ago, and since then it has gotten progressively worse. The knee pain is not constant but becomes most noticeable when going up or down the stairs. She also endorses that her knee becomes uncomfortable towards the end of class. Her father is worried because the pain is affecting her ability to play basketball, and she has college scouts coming to watch her play. The patient has no chronic medical conditions. She had a tonsillectomy as a child. She takes a multivitamin and uses ibuprofen as needed for the pain. On physical examination, there is tenderness at the inferior pole of the patella, without swelling or overlying skin changes. Which of the following is the most likely diagnosis?", "answer": "Patellar tendonitis", "options": {"A": "Osgood-Schlatter disease", "B": "Patellar stress fracture", "C": "Patellar tendonitis", "D": "Patellofemoral syndrome", "E": "Prepatellar bursitis"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 60-year-old man presents to the physician for his 10-year colonoscopy screening. He has no complaints except for occasional diarrhea and dribbling of urine. He says that he is on a healthy diet and exercises 3 days a week. He quit smoking 5 years ago after smoking 1 pack of cigarettes per day for 20 years. He has hypertension and dyslipidemia. He has benign prostatic hyperplasia that was diagnosed last year. On physical examination, his abdomen is lax with no tenderness or rigidity. Rectal examination reveals no blood in the rectal vault. Colonoscopy reveals a 4 x 3 cm polyp in the sigmoid colon. Multiple biopsies are obtained and sent for pathologic examination. Genetic testing reveals a mutation in the KRAS gene. Which of the following pathological type of polyp does this patient most likely have that also puts him at higher risk of malignancy?", "answer": "Villous adenomatous polyps", "options": {"A": "Hamartomatous polyps", "B": "Villous adenomatous polyps", "C": "Tubular adenomatous polyps", "D": "Hyperplastic polyps", "E": "Submucosal polyps"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 20-year-old healthy female volunteer is enrolled in a study involving renal perfusion. The medical history is unremarkable and she takes no medications. She denies smoking, drinking, and drug use. The family history is unremarkable. The physical examination reveals no abnormal findings. A drug which is known to selectively act on a segment of the renal vasculature is administered and the glomerular filtration rate (GFR) and filtration fraction (FF) both increase. Which of the following could be the mechanism of action of the administered drug?", "answer": "Efferent arteriole constriction", "options": {"A": "Efferent arteriole constriction", "B": "Renal artery constriction", "C": "Efferent arteriole dilation", "D": "Increased peritubular capillary permeability", "E": "Afferent arteriole constriction"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 3-year-old male is brought to the emergency room by his mother for a rash and fever. The mother reports that the child first developed a cough and malaise three days ago. Over the last 24 hours, a rash developed and the patient had a temperature up to 101.4°F (38.6°C) the night prior to presentation. The child’s medical history is notable for a prior hospitalization at the age of 2 for fever, vomiting, and lethargy. During that hospitalization, a cerebrospinal fluid sample demonstrated gram-negative diplococci. His current temperature is 100.9°F (38.3°C), blood pressure is 130/85 mmHg, pulse is 115/min, and respirations are 22/min. Physical examination reveals a lethargic male child with a diffuse petechial skin rash that is most prominent on the trunk and legs. This patient most likely has a deficiency in which of the following factors?", "answer": "C5", "options": {"A": "C1q", "B": "C2", "C": "C3", "D": "C4", "E": "C5"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 13-month-old boy is brought to the physician for the evaluation of rectal bleeding that occurred earlier that morning. The patient has also had several itchy and red skin lesions that started on his scalp and spread downwards. The parents report that their son has had six episodes of bilateral otitis media since birth. His immunizations are up-to-date. He is at the 3rd percentile for height and weight. His vital signs are within normal limits. Examination shows several eczematous lesions over the scalp, neck, and upper and lower extremities, as well as multiple red spots that do not blanch on pressure. The remainder of the physical examination shows no abnormalities. Laboratory studies show:\nHemoglobin 9.4 g/dL\nLeukocyte count 11,500/mm3\nPlatelet count 30,000/mm3\nProthrombin time 14 sec\nPartial thromboplastin time 33 sec\nWhich of the following is the most likely diagnosis?\"", "answer": "Wiskott-Aldrich syndrome", "options": {"A": "Leukocyte adhesion deficiency", "B": "Chronic granulomatous disease", "C": "DiGeorge syndrome", "D": "Chediak-Higashi syndrome", "E": "Wiskott-Aldrich syndrome"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 28-year-old woman, gravida 3, para 2, at 34 weeks' gestation comes to the physician because of a 1-day history of dyspnea, dry cough, and chest pain. Her pulse is 112/min, respirations are 24/min, and blood pressure is 108/78 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 90%. Examination shows jugular venous distention and bilateral pitting edema below the knees that is worse on the right side. There is dullness to percussion over the right lung base. Which of the following is the most likely diagnosis?", "answer": "Pulmonary embolism", "options": {"A": "Aortic dissection", "B": "Pulmonary embolism", "C": "Panic attack", "D": "Bacterial pneumonia", "E": "Acute pericarditis"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 55-year-old man comes to the physician for a follow-up examination. One month ago, he underwent a right-sided kidney transplantation due to severe polycystic kidney disease. Following the procedure, he was started on transplant rejection prophylaxis. He has had some chest and back pain as well as frequent coughing. He has also had 5–6 bowel movements per day of loose stool and occasional vomiting. He appears pale. Temperature is 37°C (98.6°F), pulse is 80/min, and blood pressure is 155/90 mm Hg. Physical examination shows lower extremity pitting edema. Laboratory studies show:\nHemoglobin 10 g/dL\nLeukocyte count 2,500/mm3\nPlatelet count 80,000/mm3\nSerum\nUrea nitrogen 30 mg/dL\nGlucose 150 mg/dL\nWhich of the following is the most likely underlying cause of this patient's symptoms?\"", "answer": "Mycophenolate mofetil", "options": {"A": "Tacrolimus", "B": "Daclizumab", "C": "Mycophenolate mofetil", "D": "Cyclosporine", "E": "Azathioprine"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 2-year-old boy with a history of multiple hospitalizations for fever and infection undergoes immunologic evaluation. Serum CH50 assay shows inappropriately low erythrocyte lysis and further workup confirms C8 deficiency. This patient is at increased risk for recurrent infections with which of the following pathogens?", "answer": "Neisseria species", "options": {"A": "Neisseria species", "B": "Giardia species", "C": "Pneumocystis species", "D": "Nocardia species", "E": "Mycobacterium species\n\""}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 55-year-old man is brought to the emergency department because of cough and poor appetite for the past week. Since it began, he has been coughing up small amounts of malodorous phlegm. During the past two nights, he has also had night sweats. He was diagnosed with HIV infection 5 years ago. He has hypertension, type 2 diabetes mellitus, and severe heartburn. The patient is homeless and does not take any medication. He has smoked a pack of cigarettes daily for 30 years. He drinks 8–10 beers daily. His temperature is 38.9°C (102.0°F), pulse is 101/min, respirations are 25/min and blood pressure is 145/92 mm Hg. The patient appears intoxicated. Physical examination shows crackles and dullness to percussion at the right lung base. Scattered expiratory wheezing is heard throughout both lung fields. A grade 2/6 mid-systolic ejection murmur is heard along the upper right sternal border. His CD4+T-lymphocyte count is 280/mm3 (Normal ≥ 500). An x-ray of the chest shows a hazy infiltrate in the right lower lung field. Which of the following is the most likely cause of this patient's symptoms?", "answer": "Aspiration pneumonia", "options": {"A": "Bronchoalveolar carcinoma", "B": "Pneumocystis pneumonia", "C": "Aspiration pneumonia", "D": "Mitral valve regurgitation", "E": "Pharyngoesophageal diverticulum\n\""}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 2-year-old boy is brought in to his pediatrician for his annual exam, flu vaccination, and to evaluate a diaper rash. The itchy pink rash has been bothering the boy for about 1 week and over the counter, remedies are not helping. He was born at 39 weeks gestation via spontaneous vaginal delivery. He is up to date on all vaccines and is meeting all developmental milestones. During the discussion, his parents are frustrated by his behavior and inability to follow directions. Today, his vital signs are stable and normal for his age. On physical examination, the boy appears uncomfortable. His heart has a regular rate and rhythm and his lungs are clear to auscultation bilaterally. There is a pink-red, raised rash in the anogenital region and medial thighs. Additionally, there are multiple bruises on the boy’s buttocks and the back of his thighs. Some are healing and some are fresh. When questioned about the bruising, the parents become evasive and end the discussion. Which of the following is the next best step in the management of the child?", "answer": "To report to Child Protective Services", "options": {"A": "To report to Child Protective Services", "B": "To suggest that the mother use disposable diapers containing superabsorbent material", "C": "To order patch testing for allergic contact dermatitis", "D": "To obtain skin scrapings for examination by light microscopy", "E": "Mupirocin cream"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 62-year-old woman comes to the physician for the evaluation of a palpable mass in the left breast that she noticed 3 weeks ago. During this period, she has also had some left-sided blood-tinged discharge. She has hypertension, type 2 diabetes mellitus, and hypercholesterolemia. She has no children. The patient's menopause occurred at 57 years of age. Her mother died of colon cancer at the age of 65 years. The patient had smoked one pack of cigarettes daily for 30 years but quit 15 years ago. She does not drink alcohol. Her current medications include enalapril, metformin, atorvastatin, and a multivitamin. She is 165 cm (5 ft 5 in) tall and weighs 84 kg (187 lb); BMI is 30.9 kg/m2. She appears well. Her temperature is 37°C (98.6°F), pulse is 78/min, and blood pressure is 135/80 mm Hg. Examination of the breasts shows a left-sided single, nontender, firm mass with poorly defined margins in the upper outer quadrant. Biopsy of the mass confirms the diagnosis of pleomorphic lobular carcinoma in situ (LCIS) that is estrogen-receptor (ER) positive. The patient undergoes lumpectomy of the left breast and treatment with tamoxifen is started. The patient's therapy increases her risk of which of the following conditions?", "answer": "Endometrial cancer", "options": {"A": "Myelosuppression", "B": "Cardiotoxicity", "C": "Osteoporosis", "D": "Endometrial cancer", "E": "Ovarian cancer"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A confused and disoriented 32-year-old man is brought to the emergency department by his wife. He was in his usual state of health until yesterday, when he started complaining of fever and headache. This morning he was complaining of worsened headache and was acting odd, prompting his wife to bring him to the hospital. His past medical history is unremarkable. At the hospital, his temperature is 39.2°C (102.5°F), pulse is 116/min, and blood pressure is 96/64 mm Hg. Physical examination is notable for neck stiffness and a large scar across his abdomen that his wife says is from a splenectomy operation following a car accident a few years ago. He has not seen a doctor since that time. A lumbar puncture shows elevated protein, low glucose, and 1,200 WBCs with 95% polymorphonuclear cells; gram staining shows gram-positive diplococci. Which of the following is the most likely risk factor contributing to this patient's underlying diagnosis?", "answer": "Dysfunction of a single organ", "options": {"A": "Congenital humoral immunodeficiency", "B": "Congenital cellular immunodeficiency", "C": "Dysfunction of a single organ", "D": "Dysfunction of multiple organs", "E": "Undiagnosed viral infection"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A group of scientists is verifying previous research on DNA replication. The diagram illustrates the theoretical DNA replication process in bacteria such as Escherichia coli. What does the letter ‘a’ represent in this process?", "answer": "Okazaki fragments", "options": {"A": "RNA Primers", "B": "Okazaki fragments", "C": "Single-stranded DNA binding proteins", "D": "The leading strand", "E": "Replication fork"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A physician is involved in a research collaboration with a pharmaceutical company. The company invites her to give a lecture series for other physicians on new therapies in her field of expertise at a retreat center in the Caribbean. Which of the following is acceptable for the physician to accept?:\nA) Compensation for travel expenses\nB) An honorarium for speaking\nC) Assistance with preparing her presentations", "answer": "A and B", "options": {"A": "A only", "B": "B only", "C": "C only", "D": "A and B", "E": "A, B, and C"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 15-year-old teenager is brought to a pediatrician by his parents. They are concerned about his performance at school and have received several letters from his school noting that the adolescent has difficulty with reading and writing compared to his classmates and often misbehaves during class. A physical exam reveals some atypical findings. A Wechsler Intelligence Scale for Children (WISC) shows that the boy has a mild intellectual disability with an IQ of 84. Complete blood count and serum TSH levels are normal. After a careful review of all findings the pediatrician suspects the teenager may have a numerical chromosomal disorder and orders karyotype (see image). Which of the following set of findings were most likely found during the physical exam?", "answer": "Tall Stature and gynecomastia", "options": {"A": "Macroorchidism, large jaw and ears", "B": "Arachnodactyly, scoliosis and aortic root dilation", "C": "Short stature, broad chest and thick skin folds in neck", "D": "Short stature, hypotonia and obesity", "E": "Tall Stature and gynecomastia"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "Ten days after delivery, a 1500-g (3.3-lb) male newborn is feeding poorly. He was born at 32 weeks' gestation. He has had frequent episodes of vomiting for the past 2 days. He has no fever, diarrhea, or hematemesis. He appears lethargic and is difficult to arouse. His temperature is 37°C (98.6°F), pulse is 145/min, respirations are 65/min, and blood pressure is 78/55 mm Hg. The lungs are clear to auscultation. The abdomen is hard with rebound tenderness. The patient is responsive only to painful stimuli. His hemoglobin concentration is 13.0 g/dL, leukocyte count is 10,900/mm3, and platelet count is 90,000/mm3. Arterial blood gas analysis on room air shows:\npH 7.31\nPCO2 30 mm Hg\nPO2 80 mm Hg\nO2 saturation 98%\nAn x-ray of the abdomen is shown. Which of the following is the most appropriate treatment?\"", "answer": "Exploratory laparotomy", "options": {"A": "Nasogastric tube gut decompression", "B": "Exploratory laparotomy", "C": "Administration of ampicillin, gentamicin, and metronidazole", "D": "Supportive care", "E": "Barium enema\n\""}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 45-year-old man who underwent liver transplantation 3 months ago for chronic liver failure presents to the physician because of a backache following a fall from sitting. He is currently on immunosuppressive therapy with glucocorticoids and cyclosporine. He has no comorbidities. On physical examination, his vitals are within normal limits. He has tenderness over his lumbar spine. An X-ray of the lumbar spine shows a wedge compression fracture of the L1 vertebra. His serum testosterone and serum creatinine levels are normal. Bone mineral densitometry shows a T-score of –3.0. What is the most likely diagnosis?", "answer": "Transplantation-related osteoporosis", "options": {"A": "Renal osteodystrophy", "B": "Osteopenia", "C": "Osteomalacia", "D": "Rickets", "E": "Transplantation-related osteoporosis"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 56-year-old woman presents to the emergency department with acute onset of pain and redness of the skin of her right arm for the past 3 days. She has had type 2 diabetes mellitus for the past 22 years, but she is not compliant with her medications. Her temperature is 38.0°C (100.4°F), pulse is 105/min, and blood pressure is 116/74 mm Hg. On physical examination, her forearm is tender and erythematous. She is diagnosed with acute cellulitis, and intravenous clindamycin is started. On the 6th day of antibiotic therapy, the patient complains of severe watery diarrhea, fever, and abdominal tenderness without rigidity. Which of the following is the best initial diagnostic test for her current complaint?", "answer": "Polymerase chain reaction", "options": {"A": "Complete blood count with differential", "B": "Abdominal CT scan", "C": "Sigmoidoscopy or colonoscopy", "D": "Fecal occult blood test", "E": "Polymerase chain reaction"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A group of researchers attempts to determine the mean fasting triglyceride levels in patients between the ages of 30 and 60 in a suburb of Tampa, FL. Over the course of several years, the team manages to obtain the blood levels of a random sample of 10,000 volunteers who fit their inclusion criteria. The blood levels are measured and demonstrate a standard deviation of 5. Which of the following correlates with the estimated standard error of the mean for this population?", "answer": "0.05", "options": {"A": "0.02", "B": "0.05", "C": "0.10", "D": "0.15", "E": "0.25"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 14-year-old girl is brought to the physician by her mother for evaluation of several bruises on her lower extremities. She has had these bruises for about 6 weeks, and the mother is concerned that she might be bullied at school. The patient has had increasing fatigue and paleness over the past several days. She has a history of recurrent generalized tonic-clonic seizures treated with carbamazepine. She appears pale and ill. Her temperature is 37.8°C (100.1°F), pulse is 115/min, and blood pressure is 100/60 mm Hg. The lungs are clear to auscultation. Examination shows a soft, nontender abdomen with no organomegaly. There are several subcutaneous purple spots on her legs bilaterally. Her hemoglobin concentration is 8.4 g/dL, leukocyte count is 2,600/mm3, platelet count is 18,000/mm3, and reticulocyte count is 0.3%. Serum electrolyte concentrations are within normal limits. Which of the following is the most likely underlying cause of this patient's symptoms?", "answer": "Adverse effect of medication", "options": {"A": "Henoch–Schönlein purpura", "B": "Immune thrombocytopenic purpura", "C": "Sickle cell disease", "D": "Systemic lupus erythematosus", "E": "Adverse effect of medication"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 51-year-old man comes to the emergency department because of a 3-day history of shortness of breath, fever, and chills. He has no history of serious illness. His temperature is 39.5°C (103.1°F). Physical examination shows a grade 4/6, holosystolic, blowing murmur over the apex that radiates to the axilla. Crackles are heard in both lower lung fields. Examination of the extremities shows several non-tender, non-blanching, erythematous macules on the palms and soles. Histopathologic examination of these macules is most likely to show which of the following?", "answer": "Microabscesses with neutrophil infiltration of capillaries", "options": {"A": "Capillary wall rupture with fibrin thrombus formation", "B": "Microabscesses with neutrophil infiltration of capillaries", "C": "Epithelioid cells with surrounding multinucleated giant cells", "D": "Cleft-like vacuoles within the arterioles", "E": "Spiral-shaped bacteria with axial filaments in the epidermis"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "An investigator is studying the maternal and fetal consequences of a recent spike in benzodiazepine addiction in Ireland. She is particularly interested in whether benzodiazepine use contributes to oral cleft deformities in newborns exposed to alprazolam, clonazepam, or lorazepam during the first trimester. The investigator uses statistical data from the local demographic institute to calculate the number of newly diagnosed cases of oral cleft deformities in Ireland over the past 5 years. Which of the following terms describes the investigator's statistical measure of interest?", "answer": "Cumulative incidence", "options": {"A": "Mortality rate", "B": "Relative risk", "C": "Cumulative incidence", "D": "Odds ratio", "E": "Attributable risk"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 55-year-old woman comes to the office for preventive health care. She has recently migrated to the United States from Hong Kong. Her past medical history is noncontributory. She denies smoking cigarettes or drinking alcohol. She last saw a doctor at the age of 14 when she was diagnosed with appendicitis and underwent an appendectomy. Her father died of a stroke at 59 years old and her mother died of a heart attack at 66 years old. She has 2 daughters who are in good health. Temperature is 37°C (98.7°F), blood pressure is 113/85 mm Hg, pulse is 69/min, respiratory rate is 14/min, and BMI is 24 kg/m2. Cardiopulmonary and abdominal examinations are negative.\nLaboratory test\nComplete blood count\nHemoglobin 12.5 g/dL\nMCV 88 fl\nLeukocytes 5,500/mm3\nPlatelets 155,000/mm3\nBasic metabolic panel\nSerum Na+ 135 mEq/L\nSerum K+ 3.7 mEq/L\nSerum Cl- 106 mEq/L\nSerum HCO3- 25 mEq/L\nBUN 10 mg/dL\nSerum creatinine 0.8 mg/dL\nLiver function test\nSerum bilirubin 0.8 mg/dL\nAST 30 U/L\nALT 35 U/L\nALP 130 U/L (20–70 U/L)\nWhat is the next best step in management of this patient?", "answer": "Gamma glutamyl transferase", "options": {"A": "Hepatitis serology", "B": "Bone scan", "C": "Ultrasonography of the abdomen", "D": "Gamma glutamyl transferase", "E": "Anti mitochondrial antibody"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 33-year-old man presents to his primary care practitioner, complaining about the presence of white spots in both of his hands. He states that the white spots have expanded in the last few months; they are not tender nor ulcerated. His past medical history is relevant for hypothyroidism. Upon physical examination, the patient shows hypopigmented macules on both hands and on the back and shoulders adjacent to a patch of skin, with signs of excoriation and scratching. Under the Wood’s lamp, the skin lesions on the hands, back, and shoulders show fluorescence. There are no signs of inflammation in any of the skin lesions. The vital signs of the patient are within normal limits. Which is the most likely diagnosis of this condition?", "answer": "Vitiligo", "options": {"A": "Vitiligo", "B": "Tinea versicolor", "C": "Pityriasis alba", "D": "Tinea corporis", "E": "Halo nevus"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 3-year-old boy is brought to the emergency department by his mother. He started violently coughing, wheezing, and having difficulty breathing about 10 minutes ago. She had briefly left him lying on his back playing with toys and when she returned he was choking. She attempted the Heimlich maneuver with no improvement. He has a heart rate is 120/min, respiratory rate is difficult to evaluate, blood pressure of 110/65 mm Hg, and temperature of 37.0°C (98.6°F). A respiratory exam reveals wheezing and decreased breath sounds on the right side. A stat chest X-ray is ordered. Which of the following is the most likely site where the aspirated foreign body is lodged?", "answer": "Posterior segment of the right upper lobe", "options": {"A": "Basilar segment of the right upper lobe", "B": "Superior segment of the right upper lobe", "C": "Posterior segment of the right upper lobe", "D": "Basilar segment of the left lower lobe", "E": "Basilar segment of the right lower lobe"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 38-year-old man presents with weakness, loss of appetite, headaches, and irritability. He developed these symptoms gradually over the past 4 months. He was diagnosed with Crohn’s disease, which was moderate at the time of diagnosis 6 months ago. He takes methotrexate 15 mg, which effectively controls his symptoms. The patient’s vital signs include: blood pressure 105/70 mm Hg, heart rate 102/min, respiratory rate 16/min, and temperature 36.4℃ (97.5℉). On physical examination, the patient is pale. His lungs are clear to auscultation. His heart sounds are rhythmic; a short early systolic murmur can be heard over the apex of the heart. The rest of the exam is unremarkable. The patient’s blood test shows the following findings:\nErythrocytes 2.7 x 109/mm3\nHb 9.3 g/dL\nHct 37%\nMean corpuscular hemoglobin  45.2 pg/cell (2.8 fmol/cell)\nMean corpuscular volume 122 µm3 (122 fL)\nReticulocyte count 0.4%\nTotal leukocyte count 3050/mm3\nNeutrophils 62%\nLymphocytes 32%\nEosinophils 1%\nMonocytes 5%\nBasophils 0%\nPlatelet count 199,000/mm3\nWhich of the following drugs should be prescribed to this patient?", "answer": "Folic acid", "options": {"A": "Riboflavin", "B": "Niacin", "C": "Thiamine pyrophosphate", "D": "Pyridoxine", "E": "Folic acid"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 75-year-old man with coronary artery disease and mitral valve stenosis status-post coronary artery bypass graft and mitral bioprosthetic valve replacement is evaluated in the intensive care unit. His postsurgical course was complicated by ventilator-associated pneumonia and bilateral postoperative pleural effusions requiring chest tubes. He has been weaned from the ventilator and has had his chest tubes removed but has required frequent suctioning to minimize aspirations. He has been dependent on a percutaneous gastrostomy tube for enteral nutrition for the past four weeks. He is currently on aspirin, carvedilol, atorvastatin, ceftazidime, and pantoprazole. He has a history of prostate cancer status post radical prostatectomy. His temperature is 96°F (35.6°C), blood pressure is 95/55 mmHg, pulse is 50/min, and respirations are 20/min. On physical exam, he is not alert and oriented but responds with moans when stimulated. His laboratory data are listed below:\n\nSerum:\nNa+: 145 mEq/L\nCl-: 110 mEq/L\nK+: 3.4 mEq/L\nHCO3-: 26 mEq/L\nBUN: 10 mg/dL\nGlucose: 112 mg/dL\nCreatinine: 1.4 mg/dL\nThyroid-stimulating hormone: 10 µU/mL\nCa2+: 11.1 mg/dL\nPO4-: 1.0 mg/dL\nAST: 6 U/L\nALT: 10 U/L\nAlbumin: 2.5 mg/dL\nLactate dehydrogenase: 200 U/L (140-280 U/L)\nHaptoglobin: 150 mg/dL (30-200 mg/dL)\n1,25-(OH)2 D3: 10 pg/mL (15-75 pg/mL)\nParathyroid hormone: 9 pg/mL (10-60 pg/mL)\n\nLeukocyte count: 10,000 cells/mm^3 with normal differential\nHemoglobin: 9 g/dL\nHematocrit: 30 %\nPlatelet count: 165,000 /mm^3\n\nHis electrocardiogram and chest radiograph are shown in Figures A and B. What is the most likely cause of his hypercalcemia?", "answer": "Immobilization", "options": {"A": "Hemolytic anemia", "B": "Euthyroid sick syndrome", "C": "Immobilization", "D": "Malignancy", "E": "Primary hyperparathyroidism"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 35-year-old woman presents for a follow-up. The patient was diagnosed with major depressive disorder 16 months ago and has tried multiple medications with no improvement, namely bupropion, fluoxetine, sertraline, and imipramine. Upon inquiry, she assures the psychiatrist that she has been fully compliant with her medications so far but stopped her current medications a few weeks back as they did not help either. Her husband suggested her to try a herbal preparation for improving her mood. She also noted that she felt temporarily better while attending her sister’s wedding last weekend, but she still remains depressed most of the times. Which of the following would be the next best step in the treatment of this patient’s depression?", "answer": "Phenelzine", "options": {"A": "St John’s Wort", "B": "Selegiline", "C": "Phenelzine", "D": "Electroconvulsive therapy", "E": "Getting regular exercise"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 17-year-old boy is brought in by paramedics to the emergency department. He was found down at a family picnic. The boy's parents state that he tried many new foods at the picnic. Additionally, because it is springtime, many insects were out while he was playing football. His temperature is 99.5°F (37.5°C), blood pressure is 127/68 mmHg, pulse is 120/min, respirations are 33/min, and oxygen saturation is 84% on room air. Physical exam is notable for tachycardia and very minimal breath sounds bilaterally. No jugular venous distention is noted and an abdominal exam is within normal limits. Which of the following best describes an effect of the next best step in management?", "answer": "Decreased serum potassium", "options": {"A": "Decreased serum potassium", "B": "Equilibration of environmental and chest cavity pressure", "C": "Hypoglycemia", "D": "Increased systemic vascular resistance", "E": "Neuroprotective in the fetus"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 45-year-old woman comes to the emergency department with her 17-year-old son because she believes she has been poisoned by her ex-husband. She reports that her coffee tasted “strange” this morning. After breakfast, she then saw a black car drive by the house, which she concludes must have been her ex-husband, who also drives a black car. She says that since the divorce 3 years ago, her ex-husband has been seeking revenge and thinks that he has installed cameras in her apartment to spy on her and their son. She has never seen any of these cameras but when she is alone in the apartment, she can sometimes hear them beeping and feel them recording her. The son also reports his mother's coffee mug smelled of bitter almonds, which he suspects was cyanide. He agrees with the mother's distrust towards his father and reports that he has also occasionally heard a camera beeping but has not been able to find any cameras yet. The mother's vital signs are within normal limits. Physical examination shows no abnormalities. Arterial blood gas analysis on room air shows a pH of 7.4. Toxicology screening is negative. Which of the following is the best initial step in management?", "answer": "Examine mother and son separately", "options": {"A": "Ziprasidone therapy", "B": "Repetitive transcranial magnetic stimulation", "C": "Examine mother and son separately", "D": "Family therapy", "E": "Report the case to the authorities"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 2-year-old boy is brought to the physician after his adoptive mother observed jerking movements of his arms and legs earlier that morning. He was adopted from an orphanage in Albania at 4 months of age. He has a history of intellectual disability. Examination shows pale skin and light blue eyes. There is a dry, eczematous, scaly rash on the extensor surfaces of the extremities. This patient is most likely deficient in which of the following enzymes?", "answer": "Phenylalanine hydroxylase", "options": {"A": "Phenylalanine hydroxylase", "B": "α-ketoacid dehydrogenase", "C": "Cystathionine synthase", "D": "Tyrosinase", "E": "Homogentisate oxidase"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 45-year-old man comes to the physician because of a 4-month history of increased frequency of urination. He wakes up several times a night to urinate and feels fatigued during the day. He also complains of increased thirst; he drinks multiple liters of water and soda daily and still feels thirsty. Vital signs are within normal limits. Physical examination shows patches of velvety hyperpigmentation in the axilla and on the posterior neck. Laboratory evaluation in this patient is most likely to show which of the following?", "answer": "Elevated glycated hemoglobin concentration", "options": {"A": "Elevated serum thyroxine concentration", "B": "Elevated glycated hemoglobin concentration", "C": "Elevated serum prostate-specific antigen", "D": "Positive urinary leukocyte esterase", "E": "Low urine osmolality"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 69-year-old man comes to the physician with a 9-month history of worsening shortness of breath on exertion and need to urinate at night. He occasionally has palpitations but does not have chest pain. The patient had a transient ischemic attack 5 years ago for which he underwent right-sided carotid endarterectomy. He has hypertension and type 2 diabetes mellitus. Current medications include metformin, lisinopril, aspirin, and simvastatin. He appears fatigued. His pulse is 61/min, blood pressure is 120/75 mmHg, and respirations are 25/min. Pulse oximetry shows an oxygen saturation of 96%. Examination shows cold extremities. There are no murmurs or rubs on cardiac auscultation. Fine, bilateral crackles are heard at the lung bases. There is 2+ lower extremity edema. An ECG shows sinus rhythm and known T wave inversions in leads V1 to V4. Which of the following agents is most likely to improve the patient's long-term survival?", "answer": "Eplerenone", "options": {"A": "Eplerenone", "B": "Ivabradine", "C": "Furosemide", "D": "Verapamil", "E": "Digoxin"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 22-year-old woman presents to her primary care provider complaining of a facial rash. She says the rash began 3 weeks ago after hiking in the White Mountains of New Hampshire this summer. Since that time she has also experienced pain in her hands and wrists that is worse in the morning and accompanied by subjective fevers. She denies chest pain, shortness of breath, nausea, or vomiting. Vital signs are 99.6°F (37.6°F), blood pressure is 134/82 mmHg, pulse is 88/min, and respirations are 18/min. Examination demonstrates a rash on the patient's face that spares the nasolabial folds along with oral ulcers. The metacarpophalangeal joints are tender to palpation, and range of motion is limited by pain. Complete blood count demonstrates normocytic anemia with thrombocytopenia. Which of the following is the next best step in diagnosis?", "answer": "Anti-nuclear antibodies", "options": {"A": "Anti-cardiolipin antibodies", "B": "Anti-dsDNA antibodies", "C": "Anti-histone antibodies", "D": "Anti-nuclear antibodies", "E": "Anti-Smith antibodies"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 54-year-old man presents with fever and a painful jaw mass with a yellowish discharge. He says that he first noticed the jaw mass 6 weeks ago and that the mass has been progressively increasing in size. He reports a history of chronic alcoholism and currently takes more than 6 drinks daily. His temperature is 37.9°C (100.2°F). On physical examination, there is a 7 × 7 cm mass at the tip of the jaw bone with significant surrounding edema and sclerosis The mass is severely tender on light palpation and has a yellowish malodorous discharge. The oral cavity shows signs of very poor dentition. Laboratory analysis of the discharge reveals gram-positive anaerobic filamentous bacteria. Which of the following organisms is the most likely cause of this patient’s condition?", "answer": "Actinomyces israelii", "options": {"A": "Peptostreptococcus magnus", "B": "Actinomyces israelii", "C": "Nocardia asteroides", "D": "Rhizopus spp.", "E": "Eikenella corrodens"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 57-year-old homosexual man presents to the emergency department with epigastric pain. He has presented multiple times for the same complaint in the past. The patient has a past medical history of alcoholism and is homeless. He states that his symptoms at this time are constant and occur at all times of the day and are near his baseline. He also endorses fatty and foul smelling diarrhea during this time frame. Which of the following is the best initial diagnostic test for this patient’s condition?", "answer": "CT scan", "options": {"A": "CT scan", "B": "Endoscopy", "C": "Lipase", "D": "Secretin stimulation test", "E": "Stool ova and parasite analysis"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 6-year-old boy is rushed to the emergency department after being involved in a motor vehicle accident. He has abrasions on his left knee and left elbow. His wounds are cleaned and a pressure bandage is applied. Typically, neutrophils and macrophages are attracted toward the site of injury by various chemical mediators. Which of the following cells is responsible for the initial cascade by the release of TGF-β and PDGF?", "answer": "Platelets", "options": {"A": "Mast cells", "B": "Lymphocytes", "C": "Fibroblasts", "D": "Platelets", "E": "Basophils"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 70-year-old man comes to the emergency department after briefly losing consciousness and collapsing when rising from a chair. He did not sustain any injuries from his collapse. He has had a two-week history of dizziness upon standing. He has smoked one pack of cigarettes daily for 55 years. He drinks three beers and two glasses of whiskey daily. He currently takes dutasteride and tamsulosin for benign prostatic hyperplasia. His blood pressure is 120/80 mm Hg supine and 100/70 mm Hg one minute after standing with no change in pulse rate. Physical examination shows conjunctival pallor. On cardiac auscultation, there is a plopping sound followed by a low-pitched, rumbling mid-diastolic murmur heard best at the apex. Which of the following is the most likely cause of this patient's presentation?", "answer": "Cardiac tumor", "options": {"A": "Stokes-Adams attack", "B": "Constricted aortic valve orifice", "C": "Cardiac tumor", "D": "Adverse medication effect", "E": "Left ventricular dilation"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 6-month-old infant is brought to a pediatrician for his scheduled immunizations. The parents deny any specific current complaints, but his facial features differ from those of other children in the family. During the physical examination, the pediatrician notes that the infant’s vital signs are stable. His facial features include a medial epicanthic fold, a face that appears flat, and a flat occiput with low-set ears. The pediatrician also notes a single transverse palmar crease on both hands. An echocardiogram is performed which suggests that the infant has a congenital heart disease which is the most common form of congenital heart disease seen in children with this particular genetic disorder. Which of the following congenital heart diseases does this infant most likely present with?", "answer": "Atrioventricular septal defect", "options": {"A": "Supravalvar aortic stenosis", "B": "Tetralogy of Fallot", "C": "Ventricular septal defect", "D": "Atrial septal defect", "E": "Atrioventricular septal defect"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 32-year-old white woman comes to the physician because of fatigue, lethargy, and swelling of the lower legs for 2 months. She reports recurrent episodes of pain in both wrists, her right knee, and her right ankle in the past year. She has had skin problems that are aggravated by exposure to sunlight for the past 18 months. She has smoked one pack of cigarettes daily for 13 years and drinks one alcoholic beverage daily. Her temperature is 37°C (98.6°F), pulse is 92/min, and blood pressure is 115/75 mm Hg. Examination shows 2+ pretibial edema bilaterally and periorbital edema. There are erythematous patches with scaling on both cheeks. Laboratory studies show:\nHemoglobin 11.2 g/dL\nLeukocyte count 8500/mm3\nPlatelet count 130,000/mm3\nSerum\nUrea nitrogen 36 mg/dL\nGlucose 77 mg/dL\nCreatinine 0.9 mg/dL\nAlbumin 2.6 mg/dL\nTotal cholesterol 275 mg/dL\nTriglycerides 180 mg/dL\nUrine\nBlood negative\nGlucose negative\nProtein 4+\nWBC 0–1/hpf\nFatty casts numerous\nA renal biopsy specimen is most likely to show which of the following?\"", "answer": "Thickened capillary loops", "options": {"A": "Thickened capillary loops", "B": "Segmental sclerosis", "C": "Crescent formation", "D": "Splitting of basement membrane", "E": "Hypercellular glomeruli"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 60-year-old man presents to the clinic with his wife for “weird breathing” during the night. The patient’s wife says that his breathing pattern is irregular but he does not snore. The patient says he is not aware of these symptoms. Past medical history is remarkable for an NSTEMI when he was 50 years old. He spends a night at the sleep lab where his tidal volume is monitored overnight and a tracing is shown in the image below. Which of the following is most likely responsible for this patient’s breathing pattern?", "answer": "Left ventricular heart failure", "options": {"A": "Diabetic ketoacidosis", "B": "Heroin abuse", "C": "Hypothyroidism", "D": "Left ventricular heart failure", "E": "Obesity"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 72-year-old man with a history of chronic kidney disease presents to his primary care physician complaining of recurrent chest pain with activity. The patient used to have chest pain when he mowed his lawn. Now he gets chest pain whenever he walks short distances such as to get his mail. The pain resolves on its own when the patient sits and rests. His temperature is 98.2°F (36.8°C), blood pressure is 157/98 mm Hg, pulse is 80/min, respirations are 15/min, and oxygen saturation is 98% on room air. Physical exam is notable for an obese man who is in no distress. An initial ECG is unchanged from a previous ECG. The patient's first troponin is 0.06 ng/mL which is unchanged from previous troponins. Which of the following is the most likely diagnosis?", "answer": "Unstable angina", "options": {"A": "NSTEMI", "B": "Stable angina", "C": "STEMI", "D": "Unstable angina", "E": "Variant angina"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 55-year-old woman presents to the surgical oncology clinic as a new patient for evaluation of recently diagnosed breast cancer. She has a medical history of hypertension for which she takes lisinopril. She denies any surgical history. Her family history is notable for breast cancer in her maternal grandmother. She is visibly anxious during the encounter, but physical examination is otherwise unremarkable. Her primary concern today is which surgical approach will be chosen to remove her breast cancer. Which of the following procedures involves the removal of an entire breast?", "answer": "Mastectomy", "options": {"A": "Vasectomy", "B": "Mastectomy", "C": "Lumpectomy", "D": "Arthroplasty", "E": "Laminectomy"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 14-year-old female is seeing her pulmonologist in clinic after a recent asthma exacerbation. She has been adherent to her original controller medication so the physician prescribes an additional new drug which prevents IgE binding to mast cells. Which of the following did the physician add?", "answer": "Omalizumab", "options": {"A": "Ipratropium", "B": "Theophylline", "C": "Albuterol", "D": "Omalizumab", "E": "Beclamethasone"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 24-year-old man is brought in to the emergency room after being retrieved by firefighters from a burning building. The patient is responding coherently to questions but reports pain secondary to a burn on his leg. He states he also has a headache and feels dizzy. His temperature is 98.5°F (36.9°C), blood pressure is 129/66 mmHg, pulse is 126/min, respirations are 14/min, and oxygen saturation is 99% on room air. Physical exam is notable for a confused young man with dry and flushed skin. Cardiopulmonary exam reveals a normal S1 and S2 as well as clear breath sounds bilaterally. The patient’s neurological exam is within normal limits. Towards the end of his exam, the patient begins vomiting. Dermatologic exam reveals a superficial burn covering 1% of the patient’s body over his right leg. Which of the following is the best next step in management for this patient?", "answer": "100% oxygen", "options": {"A": "100% oxygen", "B": "CT scan of the head", "C": "Hydroxocobalamin", "D": "Normal saline", "E": "Ondansetron"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 29-year-old female presents to her psychiatrist with concerns that she may be \"OCD.\" She explains that she has become extremely obsessed with making sure that her fruits and vegetables are completely sanitized by first rinsing with water for exactly 60 seconds and then boiling for exactly 60 minutes. She refuses to eat any fruits or vegetables that did not undergo this process, which she began doing about 3 months ago. Which of the following vitamin deficiencies is she most likely to develop?", "answer": "Vitamin C", "options": {"A": "Vitamin A", "B": "Vitamin K", "C": "Vitamin C", "D": "Vitamin D", "E": "Vitamin E"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 73-year-old male is brought to his family practitioner by his daughter with the complaints of a spinning sensation for the past 4 weeks. He says that the room appears to be continuously spinning. This has progressively worsened over the last 4 weeks to the point that he has become bed bound and cannot walk without support. These spinning sensations are present throughout the day and do not change with position. They are associated with nausea and vomiting. He denies ear pain, ear discharge, ringing in the ear, hearing disturbances, ear fullness, head trauma, fever, or recent flu-like illness. He has a blood pressure of 133/80 mm Hg, heart rate of 80/min, respiratory rate of 12/min, and temperature of 36.7°C (98.2°F). His extraocular eye movements are normal in all directions, but a vertical nystagmus is present that does not disappear despite repetitive testing. Hearing tests are within normal limits. What is the most likely diagnosis?", "answer": "Cerebellar tumor", "options": {"A": "Acute labyrinthitis", "B": "Benign paroxysmal positional vertigo", "C": "Cerebellar tumor", "D": "Meniere's disease", "E": "Vestibular neuritis"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 79-year-old man presents to the emergency room after a syncopal event. The patient has a history of hyperlipidemia for which he is taking atorvastatin. On physical examination, his vital signs are stable, but on cardiac auscultation, you detect a crescendo-decrescendo systolic murmur loudest on the right upper sternal border radiating to the neck. On physical exam, one would also expect:", "answer": "Palpation of the carotid pulse would be weak and late relative to the patient’s heart sounds", "options": {"A": "That the murmur would best be heard in the lateral left decubitus position", "B": "The character of the murmur would be machine-like", "C": "The murmur would also have a mid-systolic click loudest before S2", "D": "The murmur would also have an opening snap", "E": "Palpation of the carotid pulse would be weak and late relative to the patient’s heart sounds"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A researcher is designing a study to examine a possible correlation between exposure to a particular pesticide and chronic bronchitis. The researcher gathers all records of patients presenting with bronchitis for the past 10 years from the local hospital and contacts the qualifying subjects to ask them about exposure to the particular pesticide. Using the data he compiles, he is able to calculate an estimate for the relative and absolute risk for developing chronic bronchitis in people who have been exposed to that pesticide. Which of the following best describes this type of study design?", "answer": "Cross-sectional study", "options": {"A": "Case-control study", "B": "Cross-sectional study", "C": "Cohort study", "D": "Randomized clinical trial", "E": "Double-blind, randomized, placebo-controlled clinical trial"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 49-year-old woman presents to her primary care physician due to fatigue and shortness of breath. She finds herself being short of breath when climbing the stairs or walking uphill. Approximately 1 year ago, she was able to partake in long-distance running and weightlifting. Two weeks ago she noticed blood-tinged sputum after severely coughing during sleep. She emigrated from Mexico to the United States 3 years ago. Her temperature is 98°F (36.7°C), blood pressure is 100/62 mmHg, pulse is 135/min and irregularly irregular, and respirations are 21/min. On physical exam her speech is hoarse. She has bilateral crackles heard in the lung bases. Which of the following will most likely be found on cardiac auscultation?", "answer": "Opening snap with a mid-to-late diastolic murmur", "options": {"A": "Crescendo-decrescendo systolic ejection murmur", "B": "High-pitched, early diastolic decrescendo murmur", "C": "Holosystolic, high-pitched murmur loudest at the apex", "D": "Holosystolic, high-pitched murmur loudest at the left lower sternal border", "E": "Opening snap with a mid-to-late diastolic murmur"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 60-year-old man presents to the physician for a follow-up examination. During the previous visit, splenomegaly was detected on the abdominal exam, which has been confirmed by abdominal ultrasound. He has no complaints other than fatigue for several months. He has no history of serious illness and takes no medications. The vital signs are within the normal range. On percussion, spleen size is 15 cm (5.9 in). Otherwise, the physical examination shows no abnormalities. The laboratory test results are as follows:\nHemoglobin 10 g/dL\nMean corpuscular volume 88 μm3\nLeukocyte count 65,000/mm3\nPlatelet count 500,000/mm3\nThe peripheral blood smear shows a predominance of neutrophils and the presence of band cells, myelocytes, promyelocytes, and blasts (< 5%). The molecular studies document the BCR-ABL1 rearrangement. Which of the following is the most appropriate pharmacotherapy at this time?", "answer": "Imatinib", "options": {"A": "All-trans retinoic acid", "B": "Aspirin", "C": "Imatinib", "D": "Hydroxyurea", "E": "No pharmacotherapy"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 45-year-old man presents to the outpatient unit with a complaint of lower extremity edema for the past few weeks. He has also been observing puffiness of the face lately. The urinalysis shows 4+ proteinuria. The serum creatinine is 3.5 mg/dL, and antinuclear antibodies are absent. The biopsy findings are given in the picture. What is the most likely cause of the following findings?", "answer": "Membranous glomerulonephritis", "options": {"A": "Membranoproliferative glomerulonephritis", "B": "Rapidly progressive glomerlonephritis", "C": "Postinfectious glomerulonephritis", "D": "Membranous glomerulonephritis", "E": "Minimal change disease"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 2-year-old male is brought to his pediatrician by his parents because of a lack of testes in his scrotum. Physical examination confirms that testes are absent from the scrotal sac and palpable masses are found bilaterally around the inguinal canal. If the child’s condition is left untreated, levels of which of the following hormones is most likely to be decreased most when the child reaches sexual maturity?", "answer": "Inhibin", "options": {"A": "FSH", "B": "LH", "C": "Testosterone", "D": "Inhibin", "E": "Prolactin"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 23-year-old man presents to the emergency department by ambulance after being rescued from a burning house. The patient was intubated in the field and is maintaining his oxygen saturation above 98%. Physical exam reveals partial or full-thickness burns across an estimated 30% of his total body surface area. His weight is 70 kg. Which of the following is the volume of isotonic fluid that should be given to this patient over the next 24 hours?", "answer": "8,400 mL", "options": {"A": "550 mL", "B": "1,100 mL", "C": "4,200 mL", "D": "8,400 mL", "E": "16,800 mL"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 28-year-old G1P0 primigravida woman at 28 weeks estimated gestational age presents for routine prenatal care. She has no complaints and says she can feel her baby move and respond to outside sounds. The patient has no significant past medical or family history. Currently, she is taking a prenatal multivitamin which contains iron and folic acid. Her blood type is A (-) negative, and her husband is A (+) positive. The patient says she stopped drinking alcohol 2 years ago and denies any history of smoking or recreational drug use. Her pulse is 90/min, blood pressure is 114/68 mm Hg, and respiratory rate is 18/min. She has gained 9.0 kg (19.8 lb) over the course of the pregnancy. Physical examination shows a gravid uterus, extending 28 cm above the pubic symphysis. Occasional movements are observed in the abdomen. There is no guarding or tenderness to palpation. Fetal heart sounds can be auscultated. The remainder of the examination is unremarkable. The patient is administered an injection of RhO(D) immunoglobulin (RhoGAM). Which of the following statements best describes the rationale for administering RhO(D) immunoglobulins (RhoGAM) in this patient?", "answer": "RhO(D) immunoglobulins will prevent anti-D antibody formation in the mother.", "options": {"A": "RhO(D) immunoglobulin will prevent hemolytic disease in this pregnancy.", "B": "The father requires RhO(D) immunoglobulin administration rather than the patient.", "C": "This patient does not require RhO(D) immunoglobulin administration for this pregnancy.", "D": "RhO(D) immunoglobulins will prevent anti-D antibody formation in the mother.", "E": "RhO(D) immunoglobulins will prevent anti-D antibody formation in the fetus."}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 51-year-old man comes to the physician for evaluation of inability to attain an erection during sexual activity for 6 months. He has had an active sexual life in the past. He reports that early morning erections are present every other day. He has a history of hypertension and diabetes mellitus. His wife recently filed for divorce. He has smoked one pack of cigarettes daily for 25 years. His only medications are enalapril and metformin. Physical examination shows no abnormalities. The underlying cause of this patient's condition is best classified as which of the following?", "answer": "Psychogenic", "options": {"A": "Hormonal", "B": "Neurogenic", "C": "Physiologic", "D": "Psychogenic", "E": "Vascular"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 49-year-old G4P4 woman comes to the clinic complaining of repeated leakage of fluid from her vagina for the past 5 months. She noticed an increase in episodes following her cold last week when she was coughing and sneezing a lot. Her past medical history is significant for Crohn disease, which is well controlled with sulfasalazine. Her last menstrual period was 1 year ago. She is currently sexually active with multiple partners with inconsistent condom use. She denies any vaginal itching, abnormal discharge, pain, subpubic pressure, urinary urges, or odors. Physical examination is significant for a bulge at the anterior vaginal wall. What is the most likely explanation for this patient’s symptoms?", "answer": "Prolapse of the bladder", "options": {"A": "Prolapse of the bladder", "B": "Detrusor muscle overactivity", "C": "Genitourinary syndrome of menopause", "D": "Rectovaginal fistula", "E": "Sexually transmitted infection"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 24-year-old woman presents to a physician with recurrent episodes of palpitations, shortness of breath, and perspiration. The episodes are self-limited and are usually preceded by specific social circumstances that she does not enjoy. There is no significant past medical history. After a complete history and physical examination, the physician diagnoses an anxiety disorder. He explains that anxiety is associated with the stimulation of the sympathetic nervous system which produces several symptoms related to anxiety such as tachycardia. Which of the following cellular mechanisms best explains the effects of stimulation of sympathetic cardiac nerves on the pacemaker cells in the sinoatrial node?", "answer": "Facilitation of If currents through HCN channels", "options": {"A": "Decreased intracellular cyclic adenosine monophosphate (cAMP) level in the sinoatrial node", "B": "Inactivation of L-type voltage-gated calcium channels", "C": "Facilitation of If currents through HCN channels", "D": "Decreased slope of prepotentials", "E": "Opening of G-protein activated potassium channels"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 14-year-old boy is brought to the office by his parents because he states that for the past 2 months he has been feeling constantly tired, and also noticed a dull pain in the pit of his stomach. The patient has no relevant family history. The vital signs include a heart rate of 105/min, a respiratory rate of 16/min, a temperature of 37.0°C (98.6°F), and a blood pressure of 111/66 mm Hg. On physical exam, the abdomen is distended with hepatomegaly 5 cm underneath the xiphoid process. The complete blood count results are as follows:\nHemoglobin 17.6 g/dL\nHematocrit 64%\nRBC 6.02 x 1012/L\nLeukocyte count\n26,300/mm3\nNeutrophils 55%\nBands 2%\nEosinophils 1%\nBasophils 0%\nLymphocytes 29%\nMonocytes 2%\nPlatelet count 480,000/mm³\nErythropoietin < 1.0 mU/mL\nThe coagulation test results are as follows:\nPartial thromboplastin time (activated) 30.9 s\nProthrombin time 14.0 s\nThe abdominal Doppler ultrasound imaging is shown in the picture. What is the most likely etiology of this patient’s diagnosis?", "answer": "Polycythemia vera", "options": {"A": "Behçet's syndrome", "B": "Antiphospholipid syndrome", "C": "Protein C deficiency", "D": "Factor V Leiden mutation", "E": "Polycythemia vera"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 17-year-old girl is presented to the clinic by her mom for hair loss. Both the girl and her mom have noted random patches of hair loss across the girl's scalp, eyebrows, and eyelashes, 1st appearing several months ago. The girl has noticed no other symptoms, though the spots of hair loss are sometimes sore. On further questioning, the girl shares that she has been very stressed lately about getting good grades and applying to colleges. She knows she needs to do well on all of her homework in order to get into a good college, so she has sometimes had to stay up late into the night to rewrite her homework over and over again so that they are 'absolutely perfect'. The physical exam shows an anxious-appearing, somewhat quiet girl. There is diffuse hair loss and thinning across her scalp, with many different hair shafts of different lengths. There is no discernible pattern to the hair loss. Which of the following is the best treatment for this patient?", "answer": "Cognitive-behavioral therapy", "options": {"A": "Benzathine penicillin", "B": "Cognitive-behavioral therapy", "C": "Intralesional steroids", "D": "Oral griseofulvin", "E": "Systemic steroids"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "In a town with a hepatitis B prevalence of 4%, a new screening test is introduced as part of a study. The first round of the study detects cases of hepatitis B using the new test, which has a sensitivity of 99% and a specificity of 77%. In the second round of the study, the same test is used again in a different population with a hepatitis B prevalence of 29%. Which of the following best describes the findings obtained from the study?", "answer": "The positive predictive value would increase in the second round.", "options": {"A": "The specificity would increase in the second round.", "B": "The positive predictive value would increase in the second round.", "C": "The sensitivity would decrease in the second round.", "D": "The negative predictive value would increase in the second round.", "E": "The positive likelihood ratio would increase in the second round."}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 5-year-old girl is brought to the physician for a well-child examination. Her mother says she has been having trouble sleeping for 3 weeks because of pruritus in her genital area. The girl has otherwise been feeling well. She is at the 45th percentile for height and 51st percentile for weight. Vital signs are within normal limits. Pelvic examination shows erythema of the vulva and perianal region. There is no vaginal discharge. Which of the following is the most appropriate next step in management?", "answer": "Perianal cellophane-tape examination", "options": {"A": "Potassium hydroxide preparation", "B": "Perianal cellophane-tape examination", "C": "Wet mount microscopy", "D": "Cultures for chlamydia and gonorrhea", "E": "Stool microscopy"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 25-year-old man comes to the emergency department because of left flank pain for 2 hours. The pain is colicky in nature and he describes it as 8 out of 10 in intensity. He has nausea and has vomited once. He had a similar episode 6 months ago for which he took naproxen. There is no personal or family history of serious illness. He is a second-year medical student and has been consuming more coffee and energy drinks than normal to stay awake and study for the past 2 days. He does not smoke or drink alcohol. He takes no medications. His temperature is 37.3°C (99.1°F), pulse is 98/min, and blood pressure is 124/78 mm Hg. The abdomen is soft and nontender. Examination of the back shows no costovertebral angle tenderness. The remainder of the examination shows no abnormalities. Urinalysis is unremarkable. Which of the following is the most likely underlying cause of this patient's symptoms?", "answer": "Ureteropelvic junction obstruction", "options": {"A": "Bilateral renal cysts", "B": "Glomerular IgA deposits", "C": "Posterior urethral valves", "D": "Ureteropelvic junction obstruction", "E": "Ascending urinary tract infection\n\""}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "An otherwise healthy 6-year-old boy presents for a follow-up visit to his pediatrician's office for persistent nocturnal enuresis. He has never been dry at night and throughout the last year the pediatrician has seen him multiple times for this issue. He and his family have tried not drinking liquids 2 hours before bed, bed wetting alarms, and a reward sticker chart with limited success. His 2 older brothers had nocturnal enuresis that resolved on its own when they were 8 years of age, but the patient often sleeps over at a friend's house and is very bothered by this problem. He has 1 soft stool a day, denies abdominal pain, dysuria, or frequency, and has been continent during the day since 3 years of age. He has a completely normal physical exam, urinalysis, and basic metabolic panel. What is the next best step in management?", "answer": "Desmopressin", "options": {"A": "Bladder training", "B": "Cognitive behavioral therapy", "C": "Desmopressin", "D": "Imipramine", "E": "Oxybutynin"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 41-year-old woman presents with acute right flank pain for the past 6 hours. She says the pain is severe, colicky, ‘comes in waves’, and is localized to the right flank. She also has associated nausea and vomiting. The patient is afebrile, and her vital signs are within normal limits. On physical examination, she is writhing in pain and moaning. There is severe right costovertebral angle tenderness. Gross hematuria is present on urinalysis. A noncontrast CT of the abdomen and pelvis reveals a 4-mm-diameter radiopaque stone obstructing the right ureteropelvic junction. Aggressive IV fluid hydration is started, and ondansetron is administered. Which of the following is the next best step in the management of this patient?", "answer": "Hydrocodone/acetaminophen", "options": {"A": "Renal ultrasound", "B": "24-hour urine chemistry", "C": "Potassium citrate", "D": "Hydrochlorothiazide", "E": "Hydrocodone/acetaminophen"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 36-year-old female presents with a 6-month history of stiffness in her joints. She reports bilateral knee pain that is worse in the morning prior to activity and stiffness of the fingers in both hands. Anti-CCP antibody tests are positive. Over several months, the patient's symptoms prove unresponsive to NSAIDs and methotrexate, and the decision is made to begin infliximab. Which of the following drugs has the most similar mechanism to inflixmab?", "answer": "Trastuzumab", "options": {"A": "Imatinib", "B": "Indomethacin", "C": "Cyclophosphamide", "D": "Trastuzumab", "E": "Allopurinol"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 55-year-old man presents to the emergency department with chest pain that started 1 hour ago and has not been improving. He has a past medical history of diabetes, hypertension, and obesity. His temperature is 98.5°F (36.9°C), blood pressure is 147/68 mmHg, pulse is 130/min, respirations are 13/min, and oxygen saturation is 100% on room air. Physical exam is notable for jugular venous distension and bilateral lower extremity pitting edema. The patient is given nitroglycerin, and his chest pain improves. Which of the following is the best explanation for this patient’s improvement in symptoms?", "answer": "Preload reduction", "options": {"A": "Coronary artery vasodilation", "B": "Decreased adrenergic tone", "C": "Decreased platelet aggregation", "D": "Mu receptor agonism", "E": "Preload reduction"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "An investigator is studying energy metabolism in athletes. Baseline serum lactate levels at rest are recorded and repeat levels are obtained directly after a 1000-meter sprint. Compared to the baseline measurements, the serum lactate levels are significantly increased after the sprint. This increase in serum lactate is necessary to regenerate an essential cofactor for which of the following enzymes?", "answer": "Glyceraldehyde-3 phosphate dehydrogenase", "options": {"A": "Glycogen phosphorylase", "B": "Glyceraldehyde-3 phosphate dehydrogenase", "C": "Phosphofructokinase-1", "D": "Pyruvate carboxylase", "E": "Succinate dehydrogenase"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A scientist is studying the development of CD8+ T cells. In his experiments, he uses a radioactive isotope to mark a population of T cells. Once injected into the thymus, these cells bind tightly to MHC I self-antigen complexes. Later in the experiment, the scientist cannot find any marked cells in the peripheral blood. Which of the following processes is responsible for the loss of these marked CD8+ cells?", "answer": "Negative selection", "options": {"A": "Positive selection", "B": "Negative selection", "C": "Activation", "D": "APC antigen presentation", "E": "IL-2 stimulation"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 65-year-old woman who has smoked 2 packs per day for forty years comes to your practice complaining of a chronic cough, dyspnea, hemoptysis, and difficulty rising from a chair. Based on CXR and biopsy slides shown, you feel that all of the following would be consistent with her diagnosis EXCEPT?", "answer": "Decreasing muscle strength with repetitive stimulation", "options": {"A": "Decreasing muscle strength with repetitive stimulation", "B": "Blurry vision", "C": "Antibodies to presynaptic calcium channels", "D": "Dry mouth", "E": "Orthostatic hypotension"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 16-month-old boy is brought to the pediatrician after his parents noticed the appearance of a rash on his face, torso, and limbs. The boy has been ill for almost 2 weeks, initiating with fever, malaise, coryza, headache, nausea, diarrhea, and a rash on both of his cheeks. Physical examination is unremarkable except for an erythematous maculopapular rash on the face, trunk, and extremities with a reticular pattern (as shown in the photograph). What is the most likely diagnosis?", "answer": "Erythema infectiosum", "options": {"A": "Measles", "B": "Chickenpox", "C": "Rubella", "D": "Erythema infectiosum", "E": "Roseola infantum"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 27-year-old woman presents to a neurologist complaining of facial pain. She reports that over the past 6 months, she has developed intermittent burning unilateral facial pain that happens over 10 seconds to 3 minutes. The pain is severe enough to completely stop her from her activities. She is worried whenever she goes out that another attack will happen and she is sad that this has limited her ability to work as a lawyer. Her past medical history is notable for irritable bowel syndrome and polycystic ovarian syndrome. She takes an oral contraceptive pill. Her temperature is 98.6°F (37°C), blood pressure is 130/75 mmHg, pulse is 75/min, and respirations are 18/min. On exam, she is a well-appearing woman who is alert, oriented, and appropriately interactive. Her pupils are 2 mm and reactive to light bilaterally. Fundoscopic examination is unremarkable. Her strength and range of motion are full and symmetric in her upper and lower extremities. This patient’s symptoms are likely due to irritation of a nerve that passes through which of the following foramina?", "answer": "Foramen rotundum", "options": {"A": "Foramen magnum", "B": "Foramen rotundum", "C": "Inferior orbital fissure", "D": "Jugular foramen", "E": "Superior orbital fissure"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 26-year-old man comes to the physician because of high-grade fever, fatigue, nausea, and headache for 4 days. The headache is constant and feels like a tight band around his head. He also reports that his eyes hurt while looking at bright lights. He has been taking acetaminophen and using cold towels to help relieve his symptoms. He works as an assistant for a nature camp organization but has been unable to go to work for 3 days. His immunization records are unavailable. His temperature is 38.5°C (101.3°F), pulse is 92/min, and blood pressure is 108/74 mm Hg. He is oriented to time, place, and person. There is no rash or lymphadenopathy. Flexion of the neck results in flexion of the knee and hip. A lumbar puncture is done; cerebrospinal fluid analysis shows an opening pressure of 80 mm H2O, leukocyte count of 93/mm3 (78% lymphocytes), a glucose concentration of 64 mg/dL, and a protein concentration of 50 mg/dL. Which of the following is the most likely causal organism?", "answer": "Coxsackievirus", "options": {"A": "Borrelia burgdorferi", "B": "Mycobacterium tuberculosis", "C": "Herpes simplex virus 1", "D": "Neisseria meningitidis", "E": "Coxsackievirus"}, "meta_info": "step2&3", "answer_idx": "E"}
{"question": "A 4-year-old girl presents to the pediatrician’s office for a physical examination prior to starting preschool. She was born at 39 weeks gestation via spontaneous vaginal delivery. She is up to date on all vaccines and is meeting all developmental milestones. Past medical history is noncontributory. She takes no medications but does take a chewable vitamin daily. She lives with her parents and older brother in a house. Today, her blood pressure is 110/65 mm Hg, heart rate is 90/min, respiratory rate is 22/min, and temperature of 37.0°C (98.6°F). On physical exam, she appears well developed and pleasant. She sits listening to the conversation and follows directions. Palpation of the heart reveals a mild parasternal heave. Auscultation reveals a normal S1 but the S2 is split and remains split during inhalation and exhalation. Additionally, there is a medium pitched midsystolic murmur that is loudest between ribs 2 and 3 on the left side and a very soft diastolic rumble. Which of the following congenital defects is the most likely cause of these findings?", "answer": "Atrial septal defect", "options": {"A": "Atrial septal defect", "B": "Coarctation of the aorta", "C": "Patent ductus arteriosus", "D": "Tetralogy of Fallot", "E": "Ventricular septal defect"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "A 24-year-old man is brought to the emergency department after his head was hit with a bat during a baseball game. His teammates state that he was unresponsive after the incident but regained consciousness after 15 minutes. The patient initially refused to go to the hospital and sat on the bench for the remainder of the game. He initially appeared fine but became increasingly confused. He appears lethargic but opens his eyes to loud verbal commands. He is oriented to person and place. His temperature is 37.1 (98.8°F), pulse is 78/min, respiratory rate is 16/min, and blood pressure is 148/87 mm Hg. Examination shows an area of soft-tissue swelling over the left temporal region. A complete blood count and serum concentrations of electrolytes, urea nitrogen, and creatinine are within the reference range. A CT scan of the head is shown. After returning from the CT scan, the patient only opens his eyes to painful stimuli and responds to questions with incomprehensible sounds. He withdraws from painful stimuli. On repeat examination, the left pupil is 6 mm in diameter and reacts minimally to light. The right pupil is 3 mm in diameter and reacts normally to light. His respiratory rate is 10/min and he is intubated in the emergency department. Which of the following is the most appropriate next step in management?", "answer": "Perform craniotomy", "options": {"A": "Perform repeat head CT", "B": "Adminster hypotonic saline", "C": "Administer dexamethasone", "D": "Perform craniotomy", "E": "Perform brain MRI"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 58-year-old woman comes to the physician for a routine follow-up examination. She has a history of type 2 diabetes mellitus, hypertension, and asthma. Last year, she received laser photocoagulation for proliferative retinopathy. Her current medications include metformin, lisinopril, and an albuterol inhaler. Her mother died of complications from diabetes. She drinks 1 glass of wine daily with dinner and does not smoke. Her temperature is 37.2°C (99°F), pulse is 92/min, respirations are 14/min, and blood pressure is 152/98 mm Hg. Cardiopulmonary examination is unremarkable. There is decreased sensation to monofilament testing of the plantar surfaces of both feet. Laboratory studies show:\nToday 6 months ago\nHemoglobin A1c 6.2% 6.4%\nSerum\nCreatinine 1.3 mg/dL 1.1 mg/dL\nUrine\nAlbumin:creatinine ratio (N < 30) 470 mg/g 260 mg/g\nThe addition of which of the following medications is most likely to have prevented this patient's progressively worsening renal function?\"", "answer": "Amlodipine", "options": {"A": "Losartan", "B": "Aspirin", "C": "Atorvastatin", "D": "Amlodipine", "E": "Gabapentin"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 4-year-old boy is brought to the physician by his mother because of a rash on his hands and feet for the past two weeks. It is intensely pruritic, especially at night. He has not had fever, headache, or diarrhea. His mother has a history of eczema. The child was due for an appointment later in the week to follow up on any potentially missing vaccinations. His temperature is 37.8°C (100.1°F). Examination shows a maculopapular rash with linear patterns affecting the interdigital spaces of the fingers and toes. The remainder of the examination shows no abnormalities. Which of the following is the most effective intervention for this patient's skin lesion?", "answer": "Topical permethrin", "options": {"A": "Oral acyclovir", "B": "Supportive care", "C": "Oral diphenhydramine", "D": "Topical permethrin", "E": "Topical clotrimazole"}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 32-year-old man comes with his wife to the primary care physician because she is concerned about his drinking behavior. Specifically, he drinks 7 drinks every day and has abandoned many social activities that he previously enjoyed. In addition, he starts drinking in the morning because he feels shaky when he does not have a drink. When asked about his behavior, the man says that he knows that he probably should drink less but feels that he is not motivated enough to change. He says that perhaps the topic should be addressed again next year. Which of the following stages does this patient's behavior most likely represent?", "answer": "Contemplation", "options": {"A": "Contemplation", "B": "Maintenance", "C": "Precontemplation", "D": "Preparation", "E": "Relapse"}, "meta_info": "step1", "answer_idx": "A"}
{"question": "An 18-month-old boy is brought to the emergency department 25 minutes after an episode of loss of consciousness. The child began crying after his 4-year-old brother snatched a toy from him. The brief shrill cry was followed by a period of expiration; he then turned blue, became unconscious, and briefly lost his muscle tone, before he stiffened and had jerky movements of his arms and legs for 15 seconds. After this episode, he immediately regained consciousness. He had a similar episode 2 weeks ago when his father refused to give him a juice box. He has been healthy and has met all his developmental milestones. Vital signs are within normal limits. He is alert and active. Cardiopulmonary examination shows no abnormalities. Neurologic examination shows no focal findings. Which of the following is the most appropriate next step in management?", "answer": "Reassurance", "options": {"A": "CT scan of the head", "B": "Echocardiography", "C": "Reassurance", "D": "Lumbar puncture", "E": "Tilt table test"}, "meta_info": "step2&3", "answer_idx": "C"}
{"question": "A 67-year-old woman presents to the ophthalmologist with complaints of worsening visual loss. She states that her vision is blurry. Driving has become difficult, particularly at night, as she experiences substantial glare and sees halos around lights. On physical examination, there is absence of a red reflex. What is the most likely cause of this patient’s visual loss?", "answer": "Cataracts", "options": {"A": "Age-related macular degeneration", "B": "Cataracts", "C": "Open-angle glaucoma", "D": "Refractive error", "E": "Retinoblastoma"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 30-year-old woman comes to the physician because of headaches and nausea for the past 3 weeks. The headaches are holocranial and last up to several hours. During this period, she has also had a swishing sound in both ears, which decreases when she turns her head to either side. She has had multiple episodes of blurring of vision and double vision for the past 2 weeks. She has vomited twice in the past week. She has nodular cystic acne and polycystic ovarian disease. Current medications include an oral contraceptive, metformin, and isotretinoin. She is 163 cm (5 ft 4 in) tall and weighs 89 kg (196 lb); BMI is 33.5 kg/m2. Her temperature is 37.3°C (99.1°F), pulse is 70/min, and blood pressure is 128/82 mm Hg. She is oriented to time, place, and person. Examination shows acne over her cheeks and back. Hirsutism is present. Visual acuity is 20/20 in both eyes. There is esotropia of the left eye. Further evaluation of this patient is most likely to show which of the following findings?", "answer": "Bilateral optic disc swelling", "options": {"A": "Hyperpigmentation of palmar creases", "B": "Bilateral optic disc swelling", "C": "Raised intra-ocular pressure", "D": "Weakness of left upper and lower extremities", "E": "Positive Brudzinski's sign"}, "meta_info": "step2&3", "answer_idx": "B"}
{"question": "A 64-year-old woman with knee osteoarthritis comes to the physician for a follow-up examination. She reports significantly improved pain control since starting celecoxib 1 month ago. A history involving which of the following conditions is most likely to explain the administration of this drug instead of another nonsteroidal anti-inflammatory drug?", "answer": "Glanzmann thrombasthenia", "options": {"A": "Myocardial infarction", "B": "Reye syndrome", "C": "Sulfa drug allergy", "D": "Glanzmann thrombasthenia", "E": "Gout"}, "meta_info": "step1", "answer_idx": "D"}
{"question": "A 48-year-old woman is admitted to the hospital and requires anticoagulation. She is administered a drug that binds tightly to antithrombin III. Which of the following drugs was administered?", "answer": "Enoxaparin", "options": {"A": "Aspirin", "B": "Warfarin", "C": "Dabigatran", "D": "Rivaroxaban", "E": "Enoxaparin"}, "meta_info": "step1", "answer_idx": "E"}
{"question": "A 20-year-old woman comes to the physician because of a 2-day history of low-grade fever and painful lesions on her left index finger. Two weeks ago, she had a painful rash on the right labia majora that resolved without treatment. Physical examination shows tender lymphadenopathy of the left epitrochlear and right inguinal region. A photograph of the left index finger is shown. Which of the following best describes the properties of the most likely virus involved?", "answer": "Enveloped virus with a double-stranded, linear DNA structure", "options": {"A": "Naked virus with a double-stranded, circular DNA structure", "B": "Naked virus with a single-stranded, positive sense, linear RNA structure", "C": "Enveloped virus with a double-stranded, linear DNA structure", "D": "Enveloped virus with a single-stranded, negative sense, linear RNA structure", "E": "Enveloped virus with a partially double-stranded, circular DNA structure"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 37-year-old man comes to the emergency department because of unsteady gait that started after waking up that morning. He has no fever, chills, headache, or myalgia. He works as a logger in Washington. His younger sister has multiple sclerosis. The patient appears pale. He is alert and responsive. His temperature is 37°C (98.9°F), pulse is 100/min, respirations are 11/min, and blood pressure is 136/86 mm Hg. Examinations shows intact cranial nerves. There is bilateral flaccid paralysis of his lower extremities. Lower extremity deep tendon reflexes are absent. The patient develops tachypnea and is admitted to the intensive care unit. Assisted breathing is started because of respiratory weakness. Which of the following is the most appropriate next step in management?", "answer": "Locate and remove tick", "options": {"A": "Perform enzyme‑linked immunosorbent assay", "B": "Administer doxycycline", "C": "Administer botulism antitoxin", "D": "Locate and remove tick", "E": "Obtain cranial MRI\n\""}, "meta_info": "step2&3", "answer_idx": "D"}
{"question": "A 43-year-old man presents requesting a sleep aid for long-standing insomnia. He says he has been having trouble falling asleep for as long as he can remember, but it has become increasingly worse after he and his wife moved to their new house. He claims that his new neighbors are jealous of his huge swimming pool and are trying to sabotage it while he sleeps. His wife even had to cancel the housewarming party that was planned for the neighbors because of her husband’s behavior. When probed further on this topic, the patient accuses the physician of being angry and hostile. What is the next best step in the management of this patient?", "answer": "Respond in a straightforward manner, be honest and non-threatening", "options": {"A": "Respond in a straightforward manner, be honest and non-threatening", "B": "Encourage the patient to inform the police", "C": "Set rules and be firm with adhering to them", "D": "Always see these patients with a chaperone", "E": "Refer this patient to another physician"}, "meta_info": "step2&3", "answer_idx": "A"}
{"question": "A 22-year-old man presents to the emergency room after an altercation with the police. The police were called because the man was acting erratically in public. On physical examination, the patient is disoriented, does not respond to questioning, and appears to be reacting to internal stimuli. Laboratory tests are performed, which are all within normal limits, including a toxicology screen. The patient becomes aggressive and is given a medication to address his acute psychotic episode. An hour later, he is found in a sustained rigid posture in his bed, with his eyes in a fixed upward gaze. Which of the following medications was most likely given to this patient?", "answer": "Haloperidol", "options": {"A": "Citalopram", "B": "Haloperidol", "C": "Phenelzine", "D": "Olanzapine", "E": "Alprazolam"}, "meta_info": "step1", "answer_idx": "B"}
{"question": "A 42-year-old man is brought to the emergency department by his wife with chills and a temperature of 38.5°C (101.3°F) for the past 2 days. The patient’s wife mentions that he recently injured his leg 5 days ago, after which she noticed that his calf was swollen, red, and painful. She says there was no pus, but that her husband was in excruciating pain. His vital signs include: temperature 38.9°C (102.1°F), blood pressure 110/75 mm Hg, and  respiratory rate 18/min. On physical examination, there is a tender mass over the left calf which is red and inflamed. Blood and wound cultures are taken. The patient is started on empiric antibiotics with vancomycin, but shows no improvement. Culture results reveal that the causative organism is resistant to the current antibiotic as well as penicillin. Which of the following antibiotic therapies would be most suitable for this patient?", "answer": "IV daptomycin", "options": {"A": "IV nafcillin", "B": "Dicloxacillin", "C": "IV daptomycin", "D": "IV vancomycin", "E": "Doxycycline"}, "meta_info": "step1", "answer_idx": "C"}
{"question": "A 63-year-old man presents to the emergency department with the sudden onset of excruciating chest pain, which he describes as a tearing sensation. He was diagnosed with essential hypertension 20 years ago, but he is not compliant with his medications. On physical examination, the temperature is 37.1°C (98.8°F), heart rate is 95/min, and blood pressure is 195/90 mm Hg in the right arm and 160/80 mm Hg in the left arm. The pulses are absent in his right leg and diminished in his left leg. A chest X-ray shows a widened mediastinum. Which of the following is the next best step?", "answer": "CT scan", "options": {"A": "CT scan", "B": "Intravenous sodium nitroprusside", "C": "Surgery", "D": "D-dimer", "E": "Intravenous ultrasound"}, "meta_info": "step2&3", "answer_idx": "A"}
