Context: A 13-year-old boy is brought to the emergency room by his mother with confusion, abdominal pain, and vomiting for the previous day. The patient’s mother says he started complaining of pain in his abdomen after he got back from school yesterday and vomited 3 times during the night. This morning, he seemed confused so she rushed him to the ER. She has also noticed that he has been urinating frequently and drinking a lot of water recently, and he has lost 6 kg (13.2 lb) over the past 20 days. His vital signs include: blood pressure 100/50 mm Hg, heart rate 110/min, respiratory rate 27/min, and temperature 35.6°C (96.0°F). His BMI is 18 kg/m2. On physical examination, he is disoriented to time and place and is taking deep and labored breaths. There is diffuse tenderness to palpation in the abdomen with guarding. Laboratory tests are significant for a pH of 7.19 and a blood glucose level of 754 mg/dL. The doctor explains to his mother that her son has developed a life-threatening complication of a disease characterized by decreased levels of a hormone. Which of the following would you most likely expect to see in this patient?

Question: Which of the following would you most likely expect to see in this patient?

Answer: Decreased glucose uptake by adipocytes


Context:
A 58-year-old woman presents to the emergency department because of worsening abdominal pain for the past 2 days. She reports nausea and vomiting and is unable to tolerate oral intake. She appears uncomfortable. Her temperature is 38.1°C (100.6°F), the pulse is 92/min, the respirations are 18/min, and the blood pressure is 132/85 mm Hg. Physical examination shows yellowish discoloration of her sclera. Her abdomen is tender in the right upper quadrant. There is no abdominal distention or organomegaly. The laboratory tests show the following results:
Hemoglobin 13 g/dL
Leukocyte count 16,000/mm3
Urea nitrogen 25 mg/dL
Creatinine 2 mg/dL
Alkaline phosphatase 432 U/L
Alanine aminotransferase 196 U/L
Aspartate transaminase 207 U/L
Bilirubin
Total 3.8 mg/dL
Direct 2.7 mg/dL
Lipase 82 U/L
Ultrasound of the right upper quadrant shows dilated intrahepatic and extrahepatic bile ducts and multiple hyperechoic spheres within the gallbladder. The pancreas is not well visualized. Intravenous fluid resuscitation and antibiotic therapy with ceftriaxone and metronidazole are initiated. After 12 hours, the patient appears acutely ill and is not oriented to time. Her temperature is 39.1°C (102.4°F), the pulse is 105/min, the respirations are 22/min, and the blood pressure is 112/82 mm Hg. Which of the following is the most appropriate next step in management?

Question: Which of the following is the most appropriate next step in management?

Answer: Endoscopic retrograde cholangiopancreatography (ERCP)


Context: A 62-year-old man presents to his primary care doctor with continued hypertension despite adherence to multiple anti-hypertensive medications. The physician suspects that the patient may have elevated aldosterone levels and wants to initiate a trial of an aldosterone receptor antagonist. The patient is very concerned about side effects, particularly impotence and gynecomastia, as he had a friend who took a similar medication and had these side-effects. Which of the following is the best medication to initiate, given his concerns and the physician's diagnosis?

Question: Which of the following is the best medication to initiate, given his concerns and the physician's diagnosis?

Answer: Eplerenone


Context: A 30-year-old woman presents to the emergency department with a recent episode of chest pain. She says she was previously well and denies any history of similar symptoms. She reports that, at onset, she felt as if she was going to die and says her heart beating has been beating really fast. There was also profuse sweating, and she says she feels short of breath. She could not recall how long the event lasted but can remember that the symptoms did go away on their own by the time she arrived at the emergency department. Her vitals rapidly returned to normal while giving her medical history and she begins to look and act more calm. No significant past medical history or current medications.  Physical examination is unremarkable. Her electrocardiogram and initial cardiac enzymes are normal. Which the following is necessary to confirm the most likely diagnosis in this patient?

Question: Which the following is necessary to confirm the most likely diagnosis in this patient?

Answer: 1 month of associated symptoms


Context: A previously healthy 14-year-old boy is brought to the physician for evaluation because of loss of appetite, sleeplessness, and extreme irritability for the past 3 weeks. He was recently kicked off of the school's football team after missing too many practices. He has also been avoiding his family and friends because he is not in the mood to see them, but he admits that he is lonely. He has not left his room for 2 days, which prompted his father to bring him to the physician. He has no medical conditions and does not take any medications. He does not drink alcohol or use recreational drugs. While the father is in the waiting room, a mental status examination is conducted, which shows a constricted affect. Cognition is intact. He says that he would be better off dead and refuses to be treated. He says he wants to use his father's licensed firearm to “end his misery” over the weekend when his parents are at church. Which of the following is the most appropriate next step in management?

Question: Which of the following is the most appropriate next step in management?

Answer: Involuntary hospitalization after informing the parents


Context: A previously healthy 6-year-old boy is brought to the physician because of generalized malaise and a palpable swelling in the left axilla. The parents report that 2 weeks ago, his daycare group visited an animal shelter, after which he developed a rash on the left hand. His temperature is 38.5°C (101.3°F). Physical examination shows three linear crusts on an erythematous background on the dorsum of the left hand. There is tender left-sided axillary and cervical lymphadenopathy. Histopathologic examination of an axillary lymph node shows necrotizing granulomas. The most likely causal organism of this patient's clinical findings is also involved in the pathogenesis of which of the following conditions?

Question: The most likely causal organism of this patient's clinical findings is also involved in the pathogenesis of which of the following conditions?

Answer: Bacillary angiomatosis


Context: A 56-year-old man is brought to the emergency department with severe dyspnea and a productive cough containing streaks of blood since the day before. He had a sudden pruritic papular rash on his right thigh when he was in the southwestern USA hiking in northern Arizona and New Mexico. The next day he developed severely painful inguinal swelling on the same side; however, he did not see a physician and controlled the pain with painkillers. There is no other history of serious illness. He does not take any other medications. He appears confused. The temperature is 39.5℃ (103.1℉), the pulse is 105/min, the respiration rate is 32/min, and the blood pressure is 95/45 mm Hg. Rales are heard in the lower lobe of the left lung on auscultation. The right inguinal lymph nodes are enlarged with a spongy consistency and an underlying hard core. The surrounding area is edematous without overlying erythema or cellulitis. A computerized tomography (CT) scan is shown in the picture. Which of the following best explains these findings?

Question: Which of the following best explains these findings?

Answer: Plague


Context: A 44-year-old man presents to the family medicine clinic for some small bumps on his left thigh. The lesions are non-pruritic and have been present for the last 3 weeks. He reports feeling fatigued and malaise for the past few months. The patient has no known medical problems and takes no medications. He smokes one pack of cigarettes per day and uses intravenous street drugs. His heart rate is 82/min, the respiratory rate is 14/min, the temperature is 36.7°C (98.1°F), and the blood pressure is 126/80 mm Hg. Auscultation of the heart is without murmurs. Lungs are clear to auscultation bilaterally. Three 2-3 mm, dome-shaped, hardened papules are noted on the left thigh. Central umbilication can be observed in each papule. There is a non-tender cervical lymphadenopathy present. Which of the following is the most likely diagnosis?

Question: Which of the following is the most likely diagnosis?

Answer: Molluscum contagiosum


Context: A prominent male politician has secret homosexual desires. However, rather than engaging in homosexual behavior, he holds rallies against gay rights and regularly criticizes gay people. The politician is displaying which of the following defense mechanisms?

Question: The politician is displaying which of the following defense mechanisms?

Answer: Reaction formation


Context:
A 55-year-old man presents to his primary care physician for a general checkup. The patient has a past medical history of diabetes, hypertension, and atrial fibrillation and is currently taking warfarin, insulin, lisinopril, and metoprolol. The patient’s brother recently died from a heart attack and he has switched to an all vegetarian diet in order to improve his health. His temperature is 98.6°F (37.0°C), blood pressure is 167/108 mmHg, pulse is 90/min, respirations are 17/min, and oxygen saturation is 98% on room air. The patient’s physical exam is unremarkable. His laboratory values are ordered as seen below.

Hemoglobin: 12 g/dL
Hematocrit: 36%
Leukocyte count: 7,550/mm^3 with normal differential
Platelet count: 197,000/mm^3
INR: 1.0

Serum:
Na+: 139 mEq/L
Cl-: 100 mEq/L
K+: 4.3 mEq/L
HCO3-: 25 mEq/L
BUN: 20 mg/dL
Glucose: 99 mg/dL
Creatinine: 1.1 mg/dL
Ca2+: 10.2 mg/dL

Which of the following is the best explanation for this patient’s laboratory values?

Question:
Hemoglobin: 12 g/dL
Hematocrit: 36%
Leukocyte count: 7,550/mm^3 with normal differential
Platelet count: 197,000/mm^3
INR: 1.0

Serum:
Na+: 139 mEq/L
Cl-: 100 mEq/L
K+: 4.3 mEq/L
HCO3-: 25 mEq/L
BUN: 20 mg/dL
Glucose: 99 mg/dL
Creatinine: 1.1 mg/dL
Ca2+: 10.2 mg/dL

Which of the following is the best explanation for this patient’s laboratory values?

Answer: Dietary changes


Context: A 20-year-old woman in the army recruit collapses during an especially hot day at basic training. She was in her normal excellent state of health prior to this event. Two weeks ago, she had an upper respiratory infection (URI) but has since recovered. Her father has chronic kidney disease (CKD), bilateral hearing loss, and vision problems. At the hospital, her temperature is 40.3°C (104.5°F), blood pressure is 85/55 mm Hg, pulse is 105/min, and respiratory rate is 24/min. On physical exam, the patient appears to have altered mental status and her skin is dry, hot, and erythematous. She is complaining of severe bilateral flank pain and generalized myalgia. Catheterization produces 200 mL of tea-colored urine. Urine dipstick is positive for blood, but urinalysis is negative for RBCs or WBCs. Which of the following is most likely responsible for her condition?

Question: Which of the following is most likely responsible for her condition?

Answer: Heat stroke


Context: A 60-year-old man with a long-standing history of chronic hepatitis C infection comes to the emergency department because of abdominal distention and scleral icterus for the past month. His heart rate is 76/min, respiratory rate is 14/min, temperature is 36.0°C (96.8°F), and blood pressure is 110/86 mm Hg. Physical examination show signs suggestive of liver cirrhosis. Which of the following signs is a direct result of hyperestrinism in cirrhotic patients?

Question: Which of the following signs is a direct result of hyperestrinism in cirrhotic patients?

Answer: Gynecomastia


Context: A 47-year-old woman seeks evaluation at your office because she has had postcoital vaginal bleeding for the past 8 months with occasional intermenstrual watery, blood-tinged vaginal discharge. Her family history is negative for malignancies and inherited disorders. She is the result of a pregnancy complicated by numerous miscarriages in the 1960s, for which her mother received diethylstilbestrol. During a pelvic examination, you notice a polypoid mass on the anterior wall of the vagina. The bimanual examination is negative for adnexal masses. You suspect the presence of carcinoma and, therefore, send tissue samples to pathology, which confirmed the presence of malignant cells. Which of the following is the most likely malignant tumor in this patient?

Question: Which of the following is the most likely malignant tumor in this patient?

Answer: Clear cell adenocarcinoma


Context: A 35-year-old man visits your office for his annual health checkup. He was diagnosed with generalized anxiety disorder 6 months ago, which is being treated with citalopram. He comments that his symptoms have improved since initiating the prescribed therapy; however, in the past 2 months, he has been unable to have sexual intercourse due to weak tumescence and low libido. His blood pressure is 122/74 mm Hg, heart rate is 75/min, and respiratory rate is 16/min. Physical examination reveals regular heart and lung sounds. What is the appropriate step in the management of this patient?

Question: What is the appropriate step in the management of this patient?

Answer: Lowering citalopram dose


Context:
A 63-year-old man comes to the physician for the evaluation of an unintentional 10-kg (22-lb) weight loss over the past 6 months. During this period, the patient has had recurrent episodes of high-grade fever, night sweats, and feelings of fatigue. Two months ago, he had herpes zoster that was treated with acyclovir. He appears pale. Temperature is 38.5°C (101.3°F), pulse is 90/min, and blood pressure 130/80 mm Hg. Physical examination shows generalized painless lymphadenopathy. The liver and the spleen are palpated 2–3 cm below the right and the left costal margin, respectively. Laboratory studies show:
Hematocrit 42%
Leukocyte count 15,000/mm3
Segmented neutrophils 46%
Eosinophils 1%
Lymphocytes 50%
Monocytes 3%
Platelet count 120,000/mm3
Blood smear shows mature lymphocytes that rupture easily and appear as artifacts on a blood smear. Flow cytometry shows lymphocytes expressing CD5, CD19, CD20, and CD23. Which of the following is the most appropriate treatment?"

Question: Which of the following is the most appropriate treatment?"

Answer: Fludarabine, cyclophosphamide, rituximab


Context: A 61-year-old man is brought to the emergency room with chest pain. He developed severe, crushing, substernal chest pain 10 hours ago while he was hiking in the Adirondack mountains. He was with 2 friends at the time who gave him aspirin before carrying him 5 miles to a town to get phone service, where they then called emergency medical services. His past medical history is notable for hypertension, diabetes mellitus, and hyperlipidemia. He takes enalapril, metformin, and atorvastatin. He has a 20-pack-year smoking history and is an avid hiker. His temperature is 100°F (37.8°C), blood pressure is 102/60 mmHg, pulse is 130/min, and respirations are 28/min. He is diaphoretic and intermittently conscious. Bilateral rales are heard on pulmonary auscultation. An electrocardiogram demonstrates ST elevations in leads I and aVL. Despite appropriate management, the patient expires. An autopsy is performed demonstrating ischemia in the left atrium and posterior left ventricle. Which of the following vessels was most likely affected in this patient?

Question: Which of the following vessels was most likely affected in this patient?

Answer: Left circumflex artery


Context: A 61-year-old man comes to the physician with several months of sharp, shooting pain in both legs. Twenty years ago, he had a painless ulcer on his penis that resolved without treatment. He has no history of serious illness. Examination shows small pupils that constrict with accommodation but do not react to light. Sensation to pinprick and light touch is decreased over the distal lower extremities. Patellar reflexes are absent bilaterally. His gait is unsteady and broad-based. This patient is at increased risk for which of the following complications?

Question: This patient is at increased risk for which of the following complications?

Answer: Thoracic aortic aneurysm


Context: A 55-year-old woman presents with severe pruritus and fatigue. She denies any similar symptoms in the past. No significant past medical history. Upon physical examination, scleral icterus is present, and significant hepatosplenomegaly is noted. Mild peripheral edema is also present. Laboratory findings are significant for elevated serum levels of bilirubin, aminotransferases, alkaline phosphatase (ALP), γ-glutamyl transpeptidase (GGTP), immunoglobulins, as well as cholesterol (especially HDL fraction). Antiviral antibodies are not present. The erythrocyte sedimentation rate is also elevated. Anti-mitochondrial antibodies are found. A liver biopsy is performed, and the histopathologic examination shows bile duct injury, cholestasis, and granuloma formation. Which of the following is the most likely diagnosis in this patient?

Question: Which of the following is the most likely diagnosis in this patient?

Answer: Primary biliary cirrhosis


Context: A 25-year-old man is brought to the emergency department after being found unconscious. He was at a college party exhibiting belligerent behavior when he suddenly passed out and fell to the ground. His past medical history is not known. His temperature is 100°F (37.8°C), blood pressure is 107/48 mmHg, pulse is 125/min, respirations are 19/min, and oxygen saturation is 99% on room air. The patient is covered with emesis and responds incoherently to questions. As the patient begins to wake up he continues vomiting. The patient is started on IV fluids, analgesics, and anti-emetics and begins to feel better. Thirty minutes later the patient presents with muscle rigidity and is no longer responding coherently to questions. His temperature is 103°F (39.4°C), blood pressure is 127/68 mmHg, pulse is 125/min, respirations are 18/min, and oxygen saturation is 98% on room air. The patient's basic laboratory studies are drawn and he is started on IV fluids, given lorazepam, and placed under a cooling blanket. Despite these initial measures, his symptoms persist. Which of the following is the best next step in management?

Question: Which of the following is the best next step in management?

Answer: Dantrolene


Context: A 13-year-old boy is brought to the emergency department because of pain in his right knee for the past week. The pain is exacerbated by jogging and climbing up stairs. He has no history of trauma to the knee. He is otherwise healthy. He is an active member of his school's gymnastics team. His vital signs are within normal limits. Examination of the right knee shows a tender swelling at the proximal tibia; range of motion is full. Knee extension against resistance causes pain in the anterior proximal tibia. The remainder of the examinations shows no abnormalities. X-ray of the right knee shows anterior tibial soft tissue swelling with fragmentation of the tibial tuberosity. Which of the following is the most appropriate next step?

Question: Which of the following is the most appropriate next step?

Answer: Administration of oral ketorolac


Context: Three days after undergoing an open cholecystectomy, an obese 57-year-old woman has fever, chills, and a headache. She has right-sided chest pain that increases on inspiration and has had a productive cough for the last 12 hours. She had an episode of hypotension after the operation that resolved with intravenous fluid therapy. She underwent an abdominal hysterectomy 16 years ago for multiple fibroids of the uterus. She has smoked one pack of cigarettes daily for 17 years. She appears uncomfortable. Her temperature is 39°C (102.2°F), pulse is 98/min, respirations are 18/min, and blood pressure is 128/82 mm Hg. Inspiratory crackles are heard at the right lung base. The abdomen is soft and nontender. There is a healing surgical incision below the right ribcage. The remainder of the examination shows no abnormalities. Which of the following is the most likely diagnosis?

Question: Which of the following is the most likely diagnosis?

Answer: Pneumonia


Context: A 55-year-old man presents with a red rash over his face for the last 3 months. The patient says he moved to Nevada 6 months ago because of a new job where he works outdoors; however, he worked indoors in an office before. His vital signs include: blood pressure 100/60 mm Hg, pulse 64/min, respiratory rate 18/min. The patient’s rash is shown in the exhibit. Which of the following is the best initial step in the treatment of this patient?

Question: Which of the following is the best initial step in the treatment of this patient?

Answer: Topical metronidazole


Context: A previously healthy 46-year-old woman comes to the physician because of progressive shortness of breath, fatigue, and chest pain during exercise for the last 6 months. She does not smoke. Her maternal uncle had similar symptoms. Cardiac examination shows wide splitting of S2. The second component of S2 is loud and best heard at the 2nd left intercostal space. The lungs are clear to auscultation. Which of the following is the most likely cause of this patient's cardiac findings?

Question: Which of the following is the most likely cause of this patient's cardiac findings?

Answer: Increased right ventricular afterload


Context: An 11-year-old boy presents to your office with pitting edema and proteinuria exceeding 3.5g in 24 hours. You suspect that this patient has experienced a loss of polyanions in his glomerular basement membranes. Which of the following findings would confirm your diagnosis?

Question: Which of the following findings would confirm your diagnosis?

Answer: Selective albuminuria


Context: A 48-year-old woman comes to the physician because of intermittent pain in her neck, right shoulder, and arm, as well as a tingling sensation in her right hand. She first noticed her symptoms after she got off a rollercoaster ride 2 months ago. Physical examination shows weakness when extending the right wrist against resistance. An MRI of the head and neck is shown. This patient's condition is most likely the result of nerve root compression by a structure derived from which of the following embryologic layers?

Question: This patient's condition is most likely the result of nerve root compression by a structure derived from which of the following embryologic layers?

Answer: Notochord


Context: A 32-year-old female is brought to the emergency room by her friend for acute onset abdominal pain. She states that she was in a kickboxing class when she suddenly developed left-sided abdominal pain. Her past medical history is significant for chlamydia. She is currently sexually active and does not use contraception. Her menstrual periods occur regularly every 30 days. Her last menstrual period ended 2 days ago. The patient’s temperature is 99°F (37.2°C), blood pressure is 110/68 mmHg, pulse is 88/min, and respirations are 14/min with an oxygen saturation of 98% on room air. On physical exam, there is left-sided, lower abdominal tenderness and guarding. Pelvic examination is notable for clear mucous in the vaginal introitus and tenderness of the left adnexa. A pelvic ultrasound with Doppler reveals a large amount of fluid in the rectouterine pouch. Which of the following is the most likely diagnosis?

Question: Which of the following is the most likely diagnosis?

Answer: Ruptured ovarian cyst


Context: A 63-year-old man from the countryside presents with leg swelling and right upper abdominal tenderness. He reports a history of myocardial infarction 4 years ago, but he has no supporting documentation. At the moment, his only medication is aspirin. He also stated that he used to have ‘high blood sugars’ when checked in the hospital 4 years ago, but he did not follow up regarding this issue. He works as a farmer and noticed that it became much harder for him to work in the last few days because of fatigue and syncope. He has a 24-pack-year history of smoking and consumes alcohol occasionally. The vital signs include: blood pressure 150/90 mm Hg, heart rate 83/min, respiratory rate 16/min, and temperature 36.5℃ (97.7℉). On physical examination, the patient is pale and acrocyanotic. There is a visible jugular vein distention and bilateral lower leg pitting edema. The pulmonary auscultation is significant for occasional bilateral wheezes. Cardiac auscultation is significant for a decreased S1, S3 gallop, and grade 3/6 systolic murmur best heard at the left sternal border in the 4th left intercostal space. Abdominal percussion and palpation are suggestive of ascites. The hepatic margin is 3 cm below the right costal margin. Hepatojugular reflux is positive. Which of the following is the most likely clinical finding observed in this patient on an echocardiogram?

Question: Which of the following is the most likely clinical finding observed in this patient on an echocardiogram?

Answer: Increased peak tricuspid regurgitation


Context: A 36-year-old woman comes to the physician because of difficulty discarding items in her home. She says that the accumulation of things in her kitchen and dining room makes regular use of these spaces incredibly difficult. Her behavior started when she was in high school. She feels anxious when she tries to discard her possessions and her husband tries to clean and organize the home. This behavior frustrates her because most of the items she saves have little emotional or monetary value. She reports that there has been no improvement despite attending cognitive behavioral therapy sessions for the past 6 months. She now feels that her behavior is “taking over” her life. She does not drink, smoke, or use illicit drugs. She takes no medications. Her temperature is 36°C (96.8°F), pulse is 90/min, respirations are 12/min, and blood pressure is 116/80 mm Hg. On mental status examination, she is calm, alert, and oriented to person, place, and time. Her mood is depressed; her speech is organized, logical, and coherent; and there are no psychotic symptoms. Which of the following is the most appropriate next step in management?

Question: Which of the following is the most appropriate next step in management?

Answer: Fluoxetine


Context:
A 59-year-old woman presents to her primary care provider complaining of diffuse bodily aches. She reports a 3-month history of gradually worsening pain in her shoulders and hips that is worse in her right hip. She has a history of hypertension and recurrent renal stones for which she takes lisinopril and hydrochlorothiazide. She was admitted to the hospital earlier in the year after falling in her front yard and sustaining a distal radius fracture and vertebral compression fracture. Her temperature is 98.5°F (36.9°C), blood pressure is 145/85 mmHg, pulse is 100/min, and respirations are 20/min. On exam, she is well-appearing with mild tenderness to palpation in her shoulders and hips. She has mild pain with hip flexion and shoulder abduction. She has full range of motion in her bilateral upper and lower extremities. Serum findings are notable for the following:

Serum:
Na+: 141 mEq/L
Cl-: 100 mEq/L
K+: 4.8 mEq/L
HCO3-: 22 mEq/L
Urea nitrogen: 17 mg/dL
Glucose: 110 mg/dL
Creatinine: 1.12 mg/dL
Ca2+: 11.2 mg/dL
Phosphate: 2.3 mg/dL
Mg2+: 1.9 mg/dL
Alkaline phosphatase: 120 U/L

A radiograph of this patient’s right hip would most likely reveal which of the following?

Question:
Serum findings are notable for the following:

Serum:
Na+: 141 mEq/L
Cl-: 100 mEq/L
K+: 4.8 mEq/L
HCO3-: 22 mEq/L
Urea nitrogen: 17 mg/dL
Glucose: 110 mg/dL
Creatinine: 1.12 mg/dL
Ca2+: 11.2 mg/dL
Phosphate: 2.3 mg/dL
Mg2+: 1.9 mg/dL
Alkaline phosphatase: 120 U/L

A radiograph of this patient’s right hip would most likely reveal which of the following?

Answer: Well-defined cystic lesion with peritrabecular fibrosis


Context: A 20-year-old woman is brought in for a psychiatric consultation by her mother who is concerned because of her daughter’s recent bizarre behavior. The patient’s father died from lung cancer 1 week ago. Though this has been stressful for the whole family, the daughter has been hearing voices and having intrusive thoughts ever since. These voices have conversations about her and how she should have been the one to die and they encourage her to kill herself. She has not been able to concentrate at work or at school. She has no other history of medical or psychiatric illness. She denies recent use of any medication. Today, her heart rate is 90/min, respiratory rate is 17/min, blood pressure is 110/65 mm Hg, and temperature is 36.9°C (98.4°F). On physical exam, she appears gaunt and anxious. Her heart has a regular rate and rhythm and her lungs are clear to auscultation bilaterally. CMP, CBC, and TSH are normal. A urine toxicology test is negative. What is the patient’s most likely diagnosis?

Question: What is the patient’s most likely diagnosis?

Answer: Brief psychotic disorder


Context: A 58-year-old woman presents to the emergency department with difficulty breathing and a sensation that her heart was racing for the past 3 days. She adds that she has lost weight over the last 7 weeks, despite a good appetite, and is anxious most of the time with difficulty sleeping at night. She has smoked 10 cigarettes per day for the past 15 years. Her blood pressure is 100/55 mmHg, temperature is 36.5°C (97.7°F), and pulse is irregular with a rate of 140–150/min. On physical examination she is thin, frail, and appears anxious. Her palms are sweaty and there are fine tremors on extension of both hands. She has a palpable smooth thyroid mass. Examination of the eyes reveals bilateral exophthalmos. An electrocardiogram is obtained and shown in the picture. Which of the following has a strong positive correlation with this patient’s heart rhythm?

Question: Which of the following has a strong positive correlation with this patient’s heart rhythm?

Answer: Age


Context: A 27-year-old male suddenly develops severe abdominal cramping and bloody diarrhea. The patient reports consuming undercooked ground beef four days prior to the onset of the symptoms. Which of the following best describes the toxin-mediated mechanism of this disease process?

Question: Which of the following best describes the toxin-mediated mechanism of this disease process?

Answer: Inhibition of the 60S ribosomal subunit, resulting in decreased protein synthesis in gastrointestinal mucosal cells


Context: A 46-year-old woman presents to her primary care physician with one week of intermittent nausea and vomiting. She does not have any sick contacts, and her medical history is significant only for diabetes well-controlled on metformin. She also complains of some weakness and back/leg pain. She says that she recently returned from traveling abroad and had been administered an antibiotic during her travels for an unknown infection. On presentation, her temperature is 98.6°F (37°C), blood pressure is 119/78 mmHg, pulse is 62/min, and respirations are 25/min. An EKG is obtained showing flattening of the T wave. After further testing, the physician prescribes a thiazide for this patient. Which of the following diseases is also associated with this patient's most likely diagnosis?

Question: Which of the following diseases is also associated with this patient's most likely diagnosis?

Answer: Wilson disease


Context: A 33-year-old man presents to the emergency department after a motor vehicle collision. He was the front seat unrestrained driver in a head-on collision. The patient has a Glasgow Coma Scale of 5 and is subsequently intubated. Physical exam is notable for subcutaneous emphysema in the clavicular area. Needle decompression and chest tube placement are performed, and the patient is stabilized after receiving 2 units of blood and 2 liters of fluid. Chest radiography demonstrates proper tube location and resolution of the pneumothorax. The patient is transferred to the trauma intensive care unit. On the unit, a repeat chest radiograph is notable for a recurrent pneumothorax with the chest tube in place. Which of the following is the most likely diagnosis?

Question: Which of the following is the most likely diagnosis?

Answer: Tracheobronchial rupture


Context: A 55-year-old man is brought to the emergency department 12 hours after the sudden onset of shortness of breath and substernal chest pain at rest; the pain is increased by inspiration. He has also had a nonproductive cough, fever, and malaise for the past 5 days. He does not smoke or use illicit drugs. His temperature is 38°C (100.4°F), pulse is 125/min, respirations are 32/min, and blood pressure is 85/45 mm Hg. Physical examination shows distended neck veins. Auscultation of the chest discloses bilateral basilar rales and muffled heart sounds. An ECG shows sinus tachycardia, diffuse ST segment elevation, low voltage QRS complexes, and fluctuating R wave amplitude. Which of the following is the most likely diagnosis?

Question: Which of the following is the most likely diagnosis?

Answer: Cardiac tamponade


Context: A 34-year-old man comes to the physician because of frequent headaches and blurry vision during the past 4 months. He has also had difficulties achieving an erection over the past few weeks. Physical examination shows a temporal visual field deficit bilaterally. An MRI of the brain shows an intrasellar mass. The mass is most likely derived from which of the following types of cells?

Question: The mass is most likely derived from which of the following types of cells?

Answer: Lactotrophs


Context: A 33-year-old G2P1 woman presents to the office because of poor diabetic control. She is currently at 18 weeks gestation and admits to having poor control of her type 1 diabetes before becoming pregnant. Her family history is non-contributory. The physical examination shows a pregnant woman with a fundal height of 20 cm (7.9 in). An abdominal ultrasound is ordered. Which of the following is the most likely congenital abnormality shown on the ultrasound?

Question: Which of the following is the most likely congenital abnormality shown on the ultrasound?

Answer: Ventricular septal defect


Context: A 45-year-old G3P3 presents complaining of the feeling of a foreign body in her vagina that worsens on standing. She does not have urinary or fecal incontinence or any other genitourinary symptoms. She has no known gynecologic diseases. There were no complications with her pregnancies, all of which were full-term vaginal deliveries. She is sexually active with her husband and no longer uses oral contraceptives. She has an 11 pack-year history of smoking. Her weight is 79 kg (174 lb) and her height is 155 cm (5 ft). Her vital signs are within normal limits. The physical examination is unremarkable. The gynecologic examination reveals descent of the cervix halfway towards the introitus. On Valsalva and standing, the cervix descents to the plane of the hymen. The uterus is not enlarged and the ovaries are non-palpable. Which of the following treatments is most reasonable to offer this patient?

Question: Which of the following treatments is most reasonable to offer this patient?

Answer: Support pessary


Context: A 36-year-old woman, gravida 2, para 2, comes to the emergency department because of sudden-onset, severe right flank pain. She was in her aerobics class when the pain started but denies any trauma to the region. She has a history of recurrent ovarian cysts. Menses occur regularly at 28-day intervals. Her temperature is 37.1°C (99.3°F). Abdominal examination shows tenderness in the right lower quadrant with guarding. Pelvic ultrasound shows a large simple cyst on the right ovary. Right ovarian artery flow is detectable on Doppler, but there is no flow detected in the right ovarian vein. Which of the following ligaments is most likely to have been involved?

Question: Which of the following ligaments is most likely to have been involved?

Answer: Infundibulopelvic ligament


Context: A 69-year-old woman comes to the physician for a routine health maintenance examination. She feels well. Physical examination shows nontender cervical and axillary lymphadenopathy. The spleen is palpated 5 cm below the costal margin. Her leukocyte count is 12,000/mm3 and platelet count is 217,000/mm3. Further evaluation is most likely to show which of the following findings?

Question: Further evaluation is most likely to show which of the following findings?

Answer: Smudge cells


Context: A 24-year-old married woman presents to the emergency department with severe abdominal pain since last night. She also complains of scant vaginal bleeding. She says she visited a physician last year who said she had a pelvic infection, but she was never treated because of insurance issues. She also says her period has been delayed this month. She is afebrile. The pulse is 124/min and the blood pressure is 100/70 mm Hg. On examination, her abdomen is distended and tender. A pregnancy test was positive. A complication of infection with which of the following organisms most likely led to this patient’s condition?

Question: A complication of infection with which of the following organisms most likely led to this patient’s condition?

Answer: Chlamydia trachomatis


Context: A 44-year-old man comes to the clinic because of a 6-month history of progressive fatigue. He has a history of intravenous heroin use. Physical examination shows scleral icterus. A serum study is positive for hepatitis C RNA. Therapy with interferon-α is initiated in combination with a second drug. The expected beneficial effect of the additional drug is most likely due to inhibition of which of the following enzymes?

Question: The expected beneficial effect of the additional drug is most likely due to inhibition of which of the following enzymes?

Answer: Inosine monophosphate dehydrogenase


Context: A 42-year-old male presents to his primary care physician complaining of fatigue. He has not been to the doctor since he was 22 years of age. He reports that over the past three months, he has felt tired and weak despite no changes in diet or exercise. He is otherwise healthy and takes no medications. Family history is notable for colorectal cancer in his father and paternal uncle, ovarian cancer in his paternal grandmother, and pancreatic cancer in his paternal uncle. Physical examination is notable for conjunctival pallor. A complete blood count reveals a hemoglobin of 9.1 g/dL and hematocrit of 31%. A stool sample is hemoccult positive and a colonoscopy reveals a fungating hemorrhagic mass in the ascending colon. Which of the following processes is most likely impaired in this patient?

Question: Which of the following processes is most likely impaired in this patient?

Answer: Mismatch repair


Context: A 38-year-old woman presents to an urgent care clinic with the complaint of epigastric discomfort and cramping pain for the past 2 hours. She states that she has experienced similar pain in the past. These episodes occur mostly after meals and often subside several hours after she finishes eating. Due to this reason she mostly avoids eating. She says she has lost a few pounds in the last couple of months. She is a smoker and drinks alcohol occasionally. Past medical history is insignificant except for chronic knee pain, for which she takes over the counter painkillers. Her temperature is 37°C (98.6°F), respiratory rate is 16/min, pulse is 77/min, and blood pressure is 120/89 mm Hg. A physical abdominal exam is unremarkable, including examination of the abdomen. Which of the following is the most likely diagnosis?

Question: Which of the following is the most likely diagnosis?

Answer: Gastric peptic ulcer


Context: A 19-year-old female college soccer player presents to a sports medicine clinic with right knee pain. One day prior she twisted her right knee and felt a “pop” while chasing after a ball. She has since felt severe throbbing knee pain and noticed a rapid increase in swelling around her knee. She is able to bear weight but feels “unstable” on her right leg. On exam, anterior drawer and Lachman’s tests are positive. The physician informs her that she has likely injured an important structure in her knee. What is the function of the structure that she has most likely injured?

Question: What is the function of the structure that she has most likely injured?

Answer: Prevent excess anterior translation of the tibia relative to the femur


Context: Six hours after birth, a newborn boy is evaluated for tachypnea. He was delivered at 41 weeks' gestation via Caesarian section and the amniotic fluid was meconium-stained. His respiratory rate is 75/min. Physical examination shows increased work of breathing. X-rays of the abdomen and chest show no abnormalities. Echocardiography shows elevated pulmonary artery pressure. He is started on an inhaled medication that increases smooth muscle cGMP, and there is immediate improvement in his tachypnea and oxygenation status. Three hours later, the newborn is tachypneic and there is blue-grey discoloration of the lips, fingers, and toes. Which of the following is the most likely cause of this infant's cyanosis?

Question: Which of the following is the most likely cause of this infant's cyanosis?

Answer: Oxidization of Fe2+ to Fe3+


Context: A study is conducted to determine the most effective ways to prevent transmission of various infective agents. One of the agents studied is a picornavirus that preferentially infects hepatocytes. The investigator determines that inactivating this virus can prevent its spread. Which of the following disinfectants is most likely to inactivate this virus?

Question: Which of the following disinfectants is most likely to inactivate this virus?

Answer: Sodium hypochlorite


Context: A 34-year-old woman comes to the physician requesting prenatal care. For the past 2 months, she has had increasing breast tenderness, nausea, 3-kg (6.6-lb) weight gain, and urinary frequency. She is not sure about the date of her last menstrual period. She has been trying to conceive with her husband since she stopped taking oral contraceptives 6 months ago; she was happy to tell him last week that she is pregnant. Her temperature is 37.2°C (99°F), pulse is 100/min, and blood pressure is 110/60 mm Hg. Physical examination shows mild, nontender abdominal enlargement. The cervical os is closed. Urine β-hCG is negative. Transvaginal ultrasonography shows no abnormalities. Which of the following is the most likely diagnosis?

Question: Which of the following is the most likely diagnosis?

Answer: Pseudocyesis


Context: A 60-year-old man comes to the physician for a routine physical examination. He lives in a group home and takes no medications. During the appointment, he frequently repeats the same information and needs to be reminded why he is at the doctor's office. He says that he is a famous poet and recently had a poem published in a national magazine. His vital signs are within normal limits. He has a constricted affect. Neurological examination shows no focal deficits. On mental status examination, he has no long-term memory deficits and is able to count in serial sevens without error. An MRI of the brain shows atrophy of the anterior thalami and small mamillary bodies. Which of the following is the most likely predisposing factor for this patient's condition?

Question: Which of the following is the most likely predisposing factor for this patient's condition?

Answer: Alcohol use disorder


Context: A medical student decides to join an immunology research center, which specifically works on capsular polysaccharide vaccine development against bacteria, such as Haemophilus influenzae type b (Hib), Neisseria meningitidis, and Streptococcus pneumoniae. As a member of a research team working on the Hib vaccine, he asks his senior colleague why capsular polysaccharides are conjugated to protein carriers like tetanus toxoid during vaccine development. Which of the following is the best response to this question?

Question: Which of the following is the best response to this question?

Answer: Conjugation with a protein carrier provides effective protection to infants


Context: An investigator is studying the pattern of glutamate release from presynaptic nerve terminals in human volunteers with Alzheimer disease. The concentration of glutamate in the CA1 region of the hippocampus is measured using magnetic resonance spectroscopy after Schaffer collateral fibers are electrically stimulated. Which of the following events most likely occurs immediately prior to the release of neurotransmitters?

Question: Which of the following events most likely occurs immediately prior to the release of neurotransmitters?

Answer: Influx of calcium


Context: A 24-year-old woman presents to a physician with a history of exposure to a close friend who was diagnosed with meningococcal meningitis. She was told by her friend that she need to see a physician because she needs to be treated as well, even if she is not having symptoms yet. She currently denies any headaches, vision changes, nausea or vomiting, or neck stiffness. Her physical exam is within normal limits. Her vital signs are stable. She is prescribed rifampin for prophylaxis with specific instructions on when to follow up if symptoms develop. When asked about the possibility of pregnancy, she mentioned that she uses combination oral contraceptive pills (OCPs) for contraception. The physician suggested that her husband should use condoms for contraception as she requires antibiotic therapy. Which of the following mechanisms best explains the need for additional contraception?

Question: Which of the following mechanisms best explains the need for additional contraception?

Answer: Rifampin alters normal gastrointestinal flora, which leads to a decrease in the enterohepatic circulation of estrogens.


Context: A 38-year-old woman comes to the physician because of a 1-month history of a painless, nonpruritic skin lesion on her right thigh. She initially thought it was an insect bite, but it has slowly increased in size over the past weeks. Her temperature is 36.7°C (98°F), pulse is 75/min, and blood pressure is 128/76 mm Hg. Physical examination shows a 0.8-cm hyperpigmented papule. When the skin lesion is squeezed, the surface retracts inwards. A photograph of the lesion is shown. Which of the following is the most likely diagnosis?

Question: Which of the following is the most likely diagnosis?

Answer: Dermatofibroma


Context: A previously healthy 3-year-old boy is brought to the physician by his parents because of fever and a rash for 6 days. His temperature is 38.9°C (102°F). Examination shows right-sided anterior cervical lymphadenopathy, bilateral conjunctival injection, erythema of the tongue and lips, and a maculopapular rash involving the hands, feet, perineum, and trunk. Which of the following is the most common complication of this patient's condition?

Question: Which of the following is the most common complication of this patient's condition?

Answer: Coronary artery aneurysm


Context: A 25-year-old man is brought to the emergency department by police. He was found at a local celebration acting very strangely and was reported by other patrons of the event. The patient is very anxious and initially is hesitant to answer questions. He denies any substance use and states that he was just trying to have a good time. The patient's responses are slightly delayed and he seems to have difficulty processing his thoughts. The patient tells you he feels very anxious and asks for some medication to calm him down. The patient has a past medical history of psoriasis which is treated with topical steroids. His temperature is 99.5°F (37.5°C), blood pressure is 120/75 mmHg, pulse is 110/min, respirations are 15/min, and oxygen saturation is 99% on room air. On physical exam, you note an anxious young man. HEENT exam reveals a dry mouth and conjunctival injection. Neurological exam reveals cranial nerves II-XII as grossly intact with normal strength and sensation in his upper and lower extremities. Cardiac exam reveals tachycardia, and pulmonary exam is within normal limits. Which of the following is the most likely intoxication in this patient?

Question: Which of the following is the most likely intoxication in this patient?

Answer: Marijuana


Context: A 75-year-old with hypertension and atrial fibrillation comes to the emergency department because of a 2-hour history of severe abdominal pain and nausea. He has smoked 1 pack of cigarettes daily for the past 45 years. The patient undergoes emergency laparotomy and is found to have dusky discoloration of the hepatic colonic flexure and an adjacent segment of the transverse colon. The most likely cause of his condition is occlusion of a branch of which of the following arteries?

Question: The most likely cause of his condition is occlusion of a branch of which of the following arteries?

Answer: Superior mesenteric artery


Context: A group of researchers from Italy conducted a case register study that included all patients from a city who had an International Classification of Diseases diagnosis and contacts with specialist psychiatric services over a 10-year period. Mortality was studied in relation to age, sex, diagnosis, care pattern, and registration interval. Standardized mortality ratios (SMRs) were calculated, with the overall SMR being 1.63 (lower when compared with studies that looked at hospitalized individuals). Men and those in younger age groups showed higher mortality rates (SMRs of 2.24 and 8.82, respectively), and mortality was also higher in the first year following registration (SMR = 2.32). Higher mortality was also found in patients with a diagnosis of alcohol and drug dependence (SMR = 3.87). The authors concluded that the overall mortality of psychiatric patients managed in a community-based setting was higher than expected; however, it was still lower than the mortality described in other psychiatric settings. The primary measure used in this study can be defined as which of the following?

Question: The primary measure used in this study can be defined as which of the following?

Answer: The observed number of deaths divided by the expected number of deaths


Context: A 10-year-old boy is brought to the emergency room by his grandparents. He is in a wheelchair with soft restraints because he has been violent and had been trying to hurt himself that day. The child’s parents died in a car accident 1 month ago. His grandparents also brought the medications he stopped taking after his parents’ death, including multivitamins, allopurinol, and diazepam. They say that their grandson has been using these medications for many years; however, they are unable to provide any medical history and claim that their grandson has been behaving strangely, exhibiting facial grimacing, irregular involuntary contractions, and writhing movements for the past few days. They also note that he has had no teeth since the time they first met him at the age of 2. An intramuscular medication is administered to calm the boy down prior to drawing blood from him for laboratory tests. Which of the following biochemical pathway abnormalities is the most likely cause of this patient’s condition?

Question: Which of the following biochemical pathway abnormalities is the most likely cause of this patient’s condition?

Answer: Hypoxanthine-guanine phosphoribosyl transferase of the purine metabolism pathway


Context: A 34-year-old woman with poorly controlled Crohn disease comes to the physician because of a 2-week history of hair loss and a rash on her face. She has also noticed that food has recently tasted bland to her. She had to undergo segmental small bowel resection several times because of intestinal obstruction and fistula formation. Examination shows several bullous, erythematous perioral plaques. There are two well-circumscribed circular patches of hair loss on the scalp. A deficiency of which of the following is the most likely cause of this patient's condition?

Question: A deficiency of which of the following is the most likely cause of this patient's condition?

Answer: Zinc


Context:
A 23-year-old woman, gravida 2, para 1, at 20 weeks of gestation comes to the physician for a routine prenatal exam. Her last pregnancy was unremarkable and she gave birth to a healthy rhesus (RhD) positive girl. Her past medical history is notable for a blood transfusion after a car accident with a complex femur fracture about 3 years ago. Her temperature is 37.2°C (99°F), pulse is 92/min, and blood pressure is 138/82 mm Hg. Examination shows that the uterus is at the umbilicus. Ultrasound examination reveals normal fetal heart rate, movement, and anatomy. Routine prenatal labs show the following:
Blood type A Rh-
Leukocyte count 11,000/mm3
Hemoglobin 12.5 g/dL
Platelet count 345,000/mm3
Serum
Anti-D antibody screen Negative
Rubella IgM Negative
Rubella IgG Negative
Varicella IgM Negative
Varicella IgG Positive
STD panel Negative
Urine
Protein Trace
Culture No growth
Cervical cytology Normal
Which of the following is the best next step in management of this patient?"

Question:
Routine prenatal labs show the following:
Blood type A Rh-
Leukocyte count 11,000/mm3
Hemoglobin 12.5 g/dL
Platelet count 345,000/mm3
Serum
Anti-D antibody screen Negative
Rubella IgM Negative
Rubella IgG Negative
Varicella IgM Negative
Varicella IgG Positive
STD panel Negative
Urine
Protein Trace
Culture No growth
Cervical cytology Normal
Which of the following is the best next step in management of this patient?"

Answer: Repeat antibody screening at 28 weeks. Administer anti-D immunoglobulin at 28 weeks and after delivery if the newborn is Rh(D) positive.


Context: A 52-year-old man presents to the physician because of ongoing shortness of breath, which is more prominent when he lies down. Occasionally, he experiences palpitations, especially during strenuous activities. In addition to this, he has been experiencing difficulty in digestion and often experiences regurgitation and dysphagia. He reports that he emigrated from Mexico 20 years ago and visits his hometown twice a year. The vital signs include: blood pressure 120/75 mm Hg, respiratory rate 19/min, and pulse 100/min. The physical examination shows jugular vein distention along with pitting edema in the ankles. Bilateral basilar crackles and an S3 gallop are heard on auscultation of the chest. A chest X-ray is taken. An electrocardiogram (ECG) shows no significant findings. What is the most likely explanation for this patient’s physical and diagnostic findings?

Question: What is the most likely explanation for this patient’s physical and diagnostic findings?

Answer: Parasitic infection


Context: A 33-year-old woman presents to her primary care physician with bilateral joint pain. She says that the pain has been slowly worsening over the past 3 days. Otherwise, she complains of fatigue, a subjective fever, and a sunburn on her face which she attributes to gardening. The patient is an immigrant from Spain and works as an office assistant. She is not aware of any chronic medical conditions and takes a multivitamin daily. Her temperature is 98.7°F (37.1°C), blood pressure is 125/64 mmHg, pulse is 80/min, respirations are 13/min, and oxygen saturation is 98% on room air. Physical exam reveals bilateral redness over the maxillary prominences. Which of the following is most likely to be seen in this patient?

Question: Which of the following is most likely to be seen in this patient?

Answer: Decreased complement levels


Context: A 40-year-old man comes to the emergency department with a 4-day history of left leg pain. Over the weekend, he scraped his left thigh when he fell on a muddy field while playing flag football with some friends. Since that time, he has had progressively worsening redness and pain in his left thigh. Past medical history is unremarkable. His temperature is 39.4°C (103.0°F), heart rate is 120/min, and blood pressure is 95/60 mm Hg. Physical exam is significant for a poorly-demarcated area of redness on his left thigh, extending to about a 10 cm radius from a small scrape. This area is extremely tender to palpation, and palpation elicits an unusual 'crunchy' sensation. CT scan shows free air in the soft tissue of the left leg. The organism that is most likely responsible for this patient's presentation is also a common cause of which of the following conditions?

Question: The organism that is most likely responsible for this patient's presentation is also a common cause of which of the following conditions?

Answer: Food-borne illness


Context:
A 75-year-old man presents to the emergency department with a racing heart and lightheadedness for 3 hours. He has had similar episodes in the past, but the symptoms never lasted this long. He denies chest pain, shortness of breath, headaches, and fevers. He had a myocardial infarction 4 years ago and currently takes captopril, metoprolol, and atorvastatin. His pulse is irregular and cardiac auscultation reveals an irregular heart rhythm. Laboratory reports show:
Serum glucose 88 mg/dL
Sodium 142 mEq/L
Potassium 3.9 mEq/L
Chloride 101 mEq/L
Serum creatinine 0.8 mg/dL
Blood urea nitrogen 10 mg/dL
Cholesterol, total 170 mg/dL
HDL-cholesterol 40 mg/dL
LDL-cholesterol 80 mg/dL
Triglycerides 170 mg/dL
Hematocrit 38%
Hemoglobin 13 g/dL
Leucocyte count 7,500/mm3
Platelet count 185,000 /mm3
Activated partial thromboplastin time (aPTT) 30 seconds
Prothrombin time (PT) 12 seconds
Cardiac enzymes Negative
An ECG shows the absence of P-waves with an irregular RR complex. A few hours later, his symptoms subside and he is discharged with an additional anticoagulation drug. Which of the following mechanisms explains how this new medication will exert its effects?

Question: Which of the following mechanisms explains how this new medication will exert its effects?

Answer: Inhibition of vitamin K-dependent clotting factors


Context: A 31-year-old man, who was hospitalized for substance-induced psychosis two days prior, has had episodic neck stiffness and pain for the past 8 hours. These episodes last for approximately 25 minutes and are accompanied by his neck rotating to the right. During the last episode, he was able to relieve the stiffness by lightly touching his jaw. He has received six doses of haloperidol for auditory hallucinations since his admission. He appears anxious. His temperature is 37.3°C (99.1°F), pulse is 108/min, and blood pressure is 128/86 mm Hg. Examination shows a flexed neck rotated to the right. The neck is rigid with limited range of motion. Which of the following is the most appropriate therapy for this patient's symptoms?

Question: Which of the following is the most appropriate therapy for this patient's symptoms?

Answer: Benztropine


Context: A 31-year-old man presents to his primary care physician with fevers, chills, and night sweats. After a physical exam and a series of laboratory tests, the patient undergoes a lymph node biopsy (Image A). Three days later, while awaiting treatment, he presents to his physician complaining of generalized swelling and is found to have 4+ protein in his urine. Which of the following pathological findings is most likely to be found on renal biopsy in this patient?

Question: Which of the following pathological findings is most likely to be found on renal biopsy in this patient?

Answer: Minimal change disease


Context: A microbiologist has isolated several colonies of Escherichia coli on an agar plate. The microbiologist exposes the agar plate to ciprofloxacin, which destroys all of the bacteria except for one surviving colony. Which of the following is the most likely mechanism of antibiotic resistance in the surviving colony?

Question: Which of the following is the most likely mechanism of antibiotic resistance in the surviving colony?

Answer: Mutation of DNA gyrase


Context: A 48-year-old man is brought to the emergency department by his son with a fever over the past day. The patient’s son adds that his father has been having some behavioral problems, as well, and that he was complaining about bugs crawling over his skin this morning even though there were no insects. Past medical history is unremarkable. No current medications. The patient was an alcoholic for several years but abruptly quit drinking 5 days ago. The patient’s temperature is 40.0°C (104.0°F), pulse is 130/min, blood pressure is 146/88 mm Hg, and respiratory rate is 24/min. On physical examination, he is confused, restless, agitated, and lacks orientation to time, place or person. Which of the following the most appropriate initial course of treatment of this patient?

Question: Which of the following the most appropriate initial course of treatment of this patient?

Answer: Diazepam


Context: Eight weeks after starting a new weight-loss medication, a 43-year-old woman with obesity comes to the physician because of greasy diarrhea, excessive belching, and flatulence. She also complains of progressively worsening night-time vision. She has had no fever, chills, or vomiting. Physical examination shows dry, scaly skin on her extremities and face. Which of the following is the most likely mechanism of action of the drug she is taking?

Question: Which of the following is the most likely mechanism of action of the drug she is taking?

Answer: Inhibition of lipase


Context: A 70-year-old man with chronic heart failure presents to the emergency department due to difficulty in breathing. The patient is a known hypertensive for 20 years maintained on amlodipine and telmisartan. The physician notes that he is also being given a diuretic that blocks the Na+ channels in the cortical collecting tubule. Which drug is being referred to in this case?

Question: Which drug is being referred to in this case?

Answer: Triamterene


Context: A 59-year-old man with a history of sickle cell disease presents to the emergency department for evaluation of his fever and night sweats. He is extremely lethargic and is unable to provide an adequate history to his physician. His wife noted that roughly 3 days ago, her husband mentioned that something bit him, but she cannot remember what exactly. The vital signs include blood pressure 85/67 mm Hg, pulse rate 107/min, and respiratory rate 35/min. Upon examination, the man is currently afebrile but is lethargic and pale. His spleen is surgically absent. There are some swollen bite marks on his right hand with red streaks extending to his elbow. Which of the following bites would be most concerning in this patient?

Question: Which of the following bites would be most concerning in this patient?

Answer: Dog bite


Context: A 30-year-old woman comes to the physician because of increasing weakness in both legs for 7 days. She also reports a tingling sensation in her legs that is exacerbated by taking a hot shower. She is sexually active with one male partner and does not use condoms. Her temperature is 37.8°C (100.1°F). Physical examination shows decreased muscle strength and clonus in both lower extremities. Patellar reflex is 4+ bilaterally and plantar reflex shows an extensor response on both sides. Abdominal reflex is absent. An MRI of the brain is shown. Which of the following findings is most likely to further support the diagnosis in this patient?

Question: Which of the following findings is most likely to further support the diagnosis in this patient?

Answer: Presence of immunoglobulin bands on cerebrospinal fluid immunofixation


Context: A group of investigators is studying the association between a fire retardant chemical used on furniture and interstitial lung disease. They use hospital records to identify 50 people who have been diagnosed with interstitial lung disease. They also identify a group of 50 people without interstitial lung disease who are matched in age and geographic location to those with the disease. The participants' exposure to the chemical is assessed by surveys and home visits. Which of the following best describes this study design?

Question: Which of the following best describes this study design?

Answer: Case-control study


Context: A 41-year-old man is brought to the emergency department after a suicide attempt. His wife found him on the bathroom floor with an empty bottle of medication next to him. He has a history of major depressive disorder. His only medication is nortriptyline. His pulse is 127/min and blood pressure is 90/61 mm Hg. Examination shows dilated pupils and dry skin. The abdomen is distended and there is dullness on percussion in the suprapubic region. An ECG shows tachycardia and a QRS complex width of 130 ms. In addition to intravenous fluid resuscitation, which of the following is the most appropriate pharmacotherapy?

Question: In addition to intravenous fluid resuscitation, which of the following is the most appropriate pharmacotherapy?

Answer: Sodium bicarbonate


Context: A 23-year-old woman presents to the hospital for elective surgery. However, due to an unexpected bleeding event, the physician had to order a blood transfusion to replace the blood lost in the surgery. After this, the patient became irritable and had difficulty breathing, suggesting an allergic reaction, which was immediately treated with epinephrine. This patient is otherwise healthy, and her history does not indicate any health conditions or known allergies. The physician suspects an immunodeficiency disorder that was not previously diagnosed. If serum is taken from this patient to analyze her condition further, which of the following would be expected?

Question: If serum is taken from this patient to analyze her condition further, which of the following would be expected?

Answer: Low IgA, normal IgG, and IgM


Context:
A 21-year-old man is brought to the emergency department 30 minutes after being found unconscious in his apartment by his mother. On arrival, he is unable to provide history. The mother reports that there is no history of serious illness in the family. The patient appears drowsy and dehydrated. His temperature is 38.5°C (101.3°F), pulse is 110/min, and blood pressure is 170/100 mm Hg. Examination shows several track marks on his forearms and large contusions over his forehead, legs, and back. There is blood coming from the mouth. The patient is catheterized and tea-colored urine is drained. Urinalysis shows:
Urine
pH 5.8
Specific gravity 1.045
Blood 3+
Glucose 3+
Proteins 1+
Ketones 1+
RBC none
WBC 0-1/hpf
Urine toxicology is positive for opiates and cocaine. Intravenous fluids and sodium nitroprusside drip are started. The patient is most likely to have which of the following?"

Question: The patient is most likely to have which of the following?"

Answer: Elevated serum creatine kinase


Context: A 30-year-old G4P3 woman at 38 weeks gestation is admitted to the labor and delivery unit complaining of contractions every 5 minutes for the past hour. Her previous births have been via uncomplicated caesarean sections, but she wishes to attempt vaginal delivery this time. Her prenatal care is notable for gestational diabetes controlled with diet and exercise. The delivery is prolonged, but the patient's pain is controlled with epidural analgesia. She delivers a male infant with Apgar scores of 8 and 9 at 1 and 5 minutes, respectively. Fundal massage is performed, but the placenta does not pass. The obstetrician manually removes the placenta, but a red mass protrudes through the vagina attached to the placenta. The patient loses 500 mL of blood over the next minute, during which her blood pressure decreases from 120/80 mmHg to 90/65 mmHg. What is the best next step in management?

Question: What is the best next step in management?

Answer: Elevate posterior fornix


Context:
A 42-year-old man comes to the physician to establish care. He recently moved to the area and has not been to a primary care physician for over 5 years. He has no history of serious illness, but has intermittent bilateral knee pain for which he takes 650 mg acetaminophen every other day. He is married with three children and is sexually active with his wife. During the past 10 years, he has unsuccessfully tried to lose weight. He has smoked one half pack of cigarettes daily for 15 years. About 2–3 times per week he has 1–2 glasses of wine with dinner. He is 160 cm (5 ft 3 in) tall and weighs 93 kg (205 lb); BMI is 36.3 kg/m2. Vital signs are within normal limits. On abdominal examination, the liver is palpated 2 to 3 cm below the right costal margin. Laboratory studies show:
Hemoglobin 12.6 g/dL
Platelet count 360,000/mm3
Hemoglobin A1c 6.3%
Serum
Ferritin 194 ng/mL
Total bilirubin 0.7 mg/dL
Alkaline phosphatase 52 U/L
Aspartate aminotransferase 92 U/L
Alanine aminotransferase 144 U/L
Hepatitis B surface antigen Negative
Hepatitis B core IgM antibody Negative
Hepatitis B surface antibody Positive
Hepatitis C antibody Negative
Antinuclear antibody titers 1:20 (N = < 1:60)
Smooth muscle antibody titers Negative
Anti-LKM1 antibody titers Negative
Transabdominal ultrasonography shows a mildly enlarged, diffusely hyperechoic liver. Which of the following is the most likely underlying cause of these liver abnormalities?"

Question: Which of the following is the most likely underlying cause of these liver abnormalities?"

Answer: Insulin resistance


Context: A 16-year-old boy is brought to the emergency department by ambulance from a soccer game. During the game, he was about to kick the ball when another player collided with his leg from the front. He was unable to stand up after this collision and reported severe knee pain. On presentation, he was found to have a mild knee effusion. Physical exam showed that his knee could be pushed posteriorly at 90 degrees of flexion but it could not be pulled anteriorly in the same position. The anatomic structure that was most likely injured in this patient has which of the following characteristics?

Question: The anatomic structure that was most likely injured in this patient has which of the following characteristics?

Answer: Runs posteriorly from the medial femoral condyle


Context: A 64-year-old male with a past medical history of two myocardial infarctions presents to the emergency room with shortness of breath. He notes that he stopped taking his furosemide two weeks prior, because he ran out of pills. On exam, his oxygen saturation is 78%, his lungs have crackles throughout, and jugular venous pulsation is located at the earlobe. EKG and troponin levels are normal. Which of the following is consistent with this man's pulmonary physiology?

Question: Which of the following is consistent with this man's pulmonary physiology?

Answer: Increased Aa gradient, decreased surface area for diffusion, increased diffusion distance


Context:
A 50-year-old man presents to the office with complaints of fever and chills for 4 weeks. He adds that he is fatigued all the time and has generalized weakness. He has drenching night sweats and has had 2 episodes of non-bilious vomiting over the past few days. He traveled to the Netherlands for 4 days a month ago. His symptoms started a few days after he returned home. Laboratory testing revealed the following:
Hemoglobin 11.2 g/dL
Hematocrit 29%
Leukocyte count 2,950/mm3
Neutrophils  59%
Bands  3%
Eosinophils 1%
Basophils  0%
Lymphocytes 31%
Monocytes  4%
Platelet count  60,000/mm3
Unconjugated bilirubin 12 mg/dL
Alanine aminotransferase 200 IU/L
Aspartate aminotransferase 355 IU/L
The peripheral blood smear showed basophilic ring- and pear-shaped structures inside many red cells and extracellular basophilic rings on Wright-Giemsa staining. Further evaluation revealed parasitemia and a few schistocytes, poikilocytes, and merozoites in tetrad formation. The findings are most consistent with which diagnosis?

Question: The findings are most consistent with which diagnosis?

Answer: Babesiosis


Context: A 41-year-old woman presents with shortness of breath that is worse when she lies on her left side. About 10 days ago, she had an episode of unexplained loss of consciousness. Past medical history is negative and family history is irrelevant. Clinical examination shows a diastolic murmur, which is prominent when she lies on her left side. Jugular venous distention is present, and chest examination reveals fine crackles that do not clear with coughing. Chest X-ray shows pulmonary congestion, and 2-dimensional echocardiogram shows a mass in the left atrium attached to the atrial septum. Which of the following is the most likely diagnosis?

Question: Which of the following is the most likely diagnosis?

Answer: Atrial myxoma


Context:
A 25-year-old man presents with painless swelling of the neck for the past week. He reports no recent fevers, night sweats, or weight loss. His past medical history is significant for human immunodeficiency virus (HIV) infection, which was diagnosed last year. He also experienced a head trauma 5 years ago, which has been complicated by residual seizures. His only medication is daily phenytoin, which was restarted after he had a seizure 3 months ago. His temperature is 36.8℃ (98.2℉). On physical examination, multiple non-tender lymph nodes, averaging 2 cm in diameter, are found to be palpable in the anterior and posterior triangles of the neck bilaterally. No other lymphadenopathy is noted. The remainder of the physical exam is unremarkable. Laboratory studies show the following:
Hemoglobin 14 g/dL
Leukocyte count 8000/mm3 with a normal differential
Platelet count 250,000/mm3
Erythrocyte sedimentation rate 40 mm/h
An excisional biopsy of one of the cervical lymph nodes is performed. The histopathologic analysis is shown in the image. Which of the following is the most likely diagnosis in this patient?

Question: Which of the following is the most likely diagnosis in this patient?

Answer: Classical Hodgkin’s lymphoma (HL)


Context: A 67-year-old woman presents to her primary care physician for urinary incontinence. She has been waking up every morning with her underwear soaked in urine. She notices that at work if she does not take regular bathroom breaks her underwear will have some urine in it. She urinates 5 to 11 times per day but she claims it is a small volume. Her current medications include lisinopril, metformin, insulin, aspirin, atorvastatin, sodium docusate, and loratadine. Her temperature is 98.2°F (36.8°C), blood pressure is 167/108 mmHg, pulse is 90/min, respirations are 15/min, and oxygen saturation is 99% on room air. Physical exam is notable for decreased pinprick sensation in the lower extremities and a systolic murmur along the right upper sternal border. Which of the following is the best treatment for this patient?

Question: Which of the following is the best treatment for this patient?

Answer: Bethanechol and intermittent straight catheterization


Context: A 55-year-old man presents into the emergency department with a severe cough and difficulty breathing. He says that he finds himself out of breath after taking a few steps, and has to sit down and rest, in order to continue. He also says that, at night, he has the greatest difficulty in breathing and usually uses at least 3 pillows to sleep comfortably. He mentions a cough that appears only at night, but which is persistent enough to wake him up from sleep. He mentions that he has had a ‘heart attack’ 5 years ago. He also says that he continues to consume alcohol on a regular basis even though his doctor has advised against it. He has brought his lab reports which he had recently got done on the suggestions of his family doctor. An electrocardiogram (ECG) and a chest X-ray are found. Which of the following is the next step in this patient’s management?

Question: Which of the following is the next step in this patient’s management?

Answer: Echocardiogram


Context: A 2-day-old boy delivered at 34 weeks gestation is found to have a murmur on routine exam. He is lying supine and is not cyanotic. He has a pulse of 195/min, and respirations of 59/min. He is found to have a nonradiating continuous machine-like murmur at the left upper sternal border. S1 and S2 are normal. The peripheral pulses are bounding. Assuming this patient has no other cardiovascular defects, what is the most appropriate treatment?

Question: Assuming this patient has no other cardiovascular defects, what is the most appropriate treatment?

Answer: Indomethacin


Context: A 12-year-old girl is brought to your psychiatry office by her parents, who are concerned that she has not made any friends since starting middle school last year. The girl tells you that she gets nervous around other children, as she cannot tell what they are feeling, when they are joking, or what she has in common with them. Her teachers describe her as “easily distracted” and “easily upset by change.” When asked about her hobbies and interests, she states that “marine biology” is her only interest and gives you a 15-minute unsolicited explanation of how to identify different penguin species. Mental status exam is notable for intense eye contact, flat affect, and concrete thought process. Which of the following is true regarding this child’s disorder?

Question: Which of the following is true regarding this child’s disorder?

Answer: Boys are more commonly affected than girls


Context: Four days after admission to the hospital for pneumonia, a 68-year-old woman develops abdominal pain and watery, foul-smelling diarrhea. Current medications include intravenous ceftriaxone and oral azithromycin. Stool cultures grow gram-positive, anaerobic rods. She is moved to an isolated hospital room. Sterilization with which of the following agents is most likely to prevent transmission of this pathogen to the next patient who will occupy her room?

Question: Sterilization with which of the following agents is most likely to prevent transmission of this pathogen to the next patient who will occupy her room?

Answer: Chlorine-based solution


Context: A 1-month-old girl is brought to the pediatrician by her parents. They are concerned that she becomes lethargic and irritated between meals. They found that feeding her often with small servings helps. She was born at 39 weeks via spontaneous vaginal delivery and is meeting all developmental milestones. Her mother has one brother that occasionally requires blood transfusions. Today, her blood pressure is 55/33 mm Hg, his heart rate is 120/min, respiratory rate is 40/min, and temperature of 37.0°C (98.6°F). On physical exam, the infant is irritated. She is slightly jaundiced. Her heart has a regular rate and rhythm and her lungs are clear to auscultation bilaterally. Her blood work shows normocytic anemia with elevated reticulocyte count and decreased haptoglobin. Sickle cell anemia and other hemoglobinopathies are also ruled out. A Coombs test is negative. Red blood cell osmotic fragility gap is normal. The physician determined that these findings are related to an enzyme deficiency. Which of the following allosterically inhibits this enzyme?

Question: Which of the following allosterically inhibits this enzyme?

Answer: Alanine


Context:
A 4-year-old boy presents for a routine checkup. The patient’s parents say he was doing well until a few weeks ago at which time he started to complain of daily abdominal cramps and occasional muscle pains. His mother also noticed that he has been less active than usual. The parents deny any complaints of headaches or convulsions. The family lives together in a house built in 1950. The patient’s temperature is 36.8°C (98.2°F), blood pressure is 100/70 mm Hg, pulse is 100/min and respirations are 20/min. Abdominal exam shows mild diffuse tenderness to palpation and normal bowel sounds. The patient’s height, weight, and head circumference are normal. Laboratory results are as follows:
Hemoglobin 7 g/dL
Mean corpuscular volume (MCV) 72
Lead level (capillary blood) 15 mcg/dL
Lead level (venous blood) 60 mcg/dL
Findings on a peripheral blood smear are shown in the image. Which of the following is the best treatment option for this patient?

Question: Which of the following is the best treatment option for this patient?

Answer: Dimercaptosuccinic acid (DMSA), also known as succimer


Context: A 39-year-old woman with poorly controlled systemic lupus erythematosus (SLE) presents to her rheumatologist for a follow-up visit. She has had intermittent myalgias, arthralgias, fatigue, and skin rashes over the past 10 years that have acutely worsened over the past year. She works as a school teacher but reports that she has had to miss several days of work due to her symptoms. She has been on hydroxychloroquine for several years but does not feel that it is adequately controlling her symptoms. She does not smoke or drink alcohol. Her temperature is 99.2°F (37.3°C), blood pressure is 130/75 mmHg, pulse is 80/min, and respirations are 18/min. On exam, she is well-appearing and in no acute distress. She has erythematous, raised plaques with keratotic scaling and follicular plugging on her hands. The physician decides to trial the patient on low-dose prednisone to better control her symptoms. At 2 months of follow-up, she reports that her flares have subsided and she has been able to return to work full-time. If this patient continues this medication regimen, she will be at an elevated risk for developing which of the following?

Question: If this patient continues this medication regimen, she will be at an elevated risk for developing which of the following?

Answer: Femoral neck fracture


Context: A 40-year-old woman presents with severe shortness of breath. The patient is unable to provide a history due to her breathing difficulties. The patient’s roommate says that she came home and found her in this state. She also says that they both occasionally take sleeping pills to help them fall asleep. Physical examination reveals an obese female, dyspneic with diminished chest wall movements. The patient’s A-a gradient is calculated to be 10 mm Hg. Which of the following most likely accounts for this patient’s symptoms?

Question: Which of the following most likely accounts for this patient’s symptoms?

Answer: Alveolar hypoventilation


Context: A 74-year-old woman is brought to her primary care doctor by her adult son. The son says she has been very difficult at home and is "losing it". He seems very frustrated about her diminishing ability to take care of herself the way she used to and no longer thinks he can trust her watching his children. At her last visit you noted mild cognitive impairment. Today, she appears withdrawn and hesitates to make eye-contact with you. She lets her son do most of the talking. Which of the following is the most appropriate next step?

Question: Which of the following is the most appropriate next step?

Answer: Ask the son to step out so you can speak with the patient alone


Context: An investigator is studying the effects of different gastrointestinal regulatory substances. A healthy subject is asked to eat a meal at hour 0, and the pH of stomach contents and rate of stomach acid secretions are measured over the next 4 hours. Results of the study are shown. Which of the following mechanisms most likely contributes to the changes seen at point D in the graph?

Question: Which of the following mechanisms most likely contributes to the changes seen at point D in the graph?

Answer: Increased activity of D cells


Context: A 45-year-old woman comes to the physician with a lump on her throat that has steadily increased in size over the past 5 months. She does not have difficulties swallowing, dyspnea, or changes in voice. Examination shows a 3-cm, hard swelling on the left side of her neck that moves with swallowing. There is no cervical or axillary lymphadenopathy. The remainder of the examination shows no abnormalities. Thyroid functions tests are within the reference range. Ultrasound of the neck shows an irregular, hypoechogenic mass in the left lobe of the thyroid. A fine-needle aspiration biopsy is inconclusive. The surgeon and patient agree that the most appropriate next step is a diagnostic lobectomy and isthmectomy. Surgery shows a 3.5-cm gray tan thyroid tumor with invasion of surrounding blood vessels, including the veins. The specimen is sent for histopathological examination. Which of the following is most likely to be seen on microscopic examination of the mass?

Question: Which of the following is most likely to be seen on microscopic examination of the mass?

Answer: Capsular invasion


Context: A 53-year-old female patient comes to the physician’s office for her annual check-up visit. She has no complaints and her past medical history is notable for diabetes and hypertension. During this visit, the patient undergoes screening procedures per guidelines including a mammogram. On the screening mammogram a spiculated, irregular mass is found on the left breast. Further diagnostic mammography and biopsy reveal ductal adenocarcinoma of the breast in the upper outer quadrant of the left breast. Which of the following is the most important factor in determining this patient’s prognosis?

Question: Which of the following is the most important factor in determining this patient’s prognosis?

Answer: Tumor stage


Context: A 2-month-old girl is brought to the pediatrician by her concerned father. He states that ever since her uncomplicated delivery she has failed to gain weight, has had chronic diarrhea, and has had multiple bacterial and viral infections. During the course of the workup, an absent thymic shadow is noted and a lymph node biopsy demonstrates the absence of germinal centers. Which of the following is the most likely cause of this patient's symptoms?

Question: Which of the following is the most likely cause of this patient's symptoms?

Answer: Adenosine deaminase deficiency


Context: A 1-year-old boy is brought to the clinic by his parents for a regular check-up. His weight, height, and head size were found to be in the lower percentile ranges on standard growth curves. His hair is tangled and has a dry, brittle texture. Genetic testing reveals that the patient has a connective tissue disorder caused by impaired copper absorption and transport. The patient’s disorder is caused by a mutation in which of the following genes?

Question: The patient’s disorder is caused by a mutation in which of the following genes?

Answer: ATP7A


Context: A 15-year-old girl is brought to the physician because she has not had a menstrual period. There is no personal or family history of serious illness. She is 165 cm (5 ft 5 in) tall and weighs 57 kg (125 lb); BMI is 21 kg/m2. Vital signs are within normal limits. Examination of the breasts shows a secondary mound formed by the nipple and areola. Pubic hair is sparse and lightly pigmented. Abdominal examination shows bilateral firm, nontender inguinal masses. Pelvic examination shows a blind-ended vaginal pouch. Ultrasonography does not show a uterus or ovaries. Which of the following is the most appropriate treatment for this patient's condition?

Question: Which of the following is the most appropriate treatment for this patient's condition?

Answer: Gonadectomy


Context: A 51-year-old man presents the emergency room with chest pain. He mentions that the pain started several hours ago and radiates to his left neck and shoulder. He also mentions that he has some difficulty in breathing. He says that he has had similar chest pains before, but nothing seemed to be wrong at that time. He was diagnosed with high cholesterol during that episode and was prescribed medication. He also has a 3-year history of gastritis. The blood pressure is 130/80 mm Hg, respirations are 18/min, and the pulse is 110/min. He seems a little anxious. The physical examination reveals no significant abnormalities. An ECG shows slight changes in the leads. His physician talks to him about the benefits of taking low-dose aspirin daily. Which of the following would be a contraindication to the use of aspirin in this patient?

Question: Which of the following would be a contraindication to the use of aspirin in this patient?

Answer: Gastritis


Context: A 45-year-old woman presents to the physician for a follow-up visit. She has no specific complaints at this visit however, she has noticed that she is more tired than usual these days. At first, she ignored it and attributed it to stress but she feels weaker each week. She is sometimes out of breath while walking for long distances or when she is involved in strenuous physical activity. She was diagnosed with rheumatoid arthritis 3 years ago and has since been on medication to assist with her pain and to slow down disease progression. Her temperature is 37.0°C (98.6°F), the respiratory rate is 15/min, the pulse is 107/min, and the blood pressure is 102/98 mm Hg. On examination, you notice thinning hair and mildly cool extremities with flattened nail beds. A complete blood count and iron studies are ordered. Which of the following is most likely to show up on her iron profile?

Question: Which of the following is most likely to show up on her iron profile?

Answer: Decreased iron-binding capacity


Context:
An 89-year-old woman is brought to the emergency department by her husband because of diarrhea and weakness for 4 days. She has 2–3 loose stools every day. She has also had 3 episodes of vomiting. She complains of a headache and blurry vision. Three weeks ago, she returned from a cruise trip to the Bahamas. She has congestive heart failure, atrial fibrillation, age-related macular degeneration, type 2 diabetes mellitus, and chronic renal failure. Current medications include warfarin, metoprolol, insulin, digoxin, ramipril, and spironolactone. Her temperature is 36.7°C (98°F), pulse is 61/min, and blood pressure is 108/74 mm Hg. The abdomen is soft, and there is diffuse, mild tenderness to palpation. Laboratory studies show:
Hemoglobin 12.9 g/dL
Leukocyte count 7200/mm3
Platelet count 230,000/mm3
Serum
Na+ 137 mEq/L
K+ 5.2 mEq/L
Glucose 141 mg/dL
Creatinine 1.3 mg/dL
Which of the following is the most appropriate next step in management?"

Question:
Laboratory studies show:
Hemoglobin 12.9 g/dL
Leukocyte count 7200/mm3
Platelet count 230,000/mm3
Serum
Na+ 137 mEq/L
K+ 5.2 mEq/L
Glucose 141 mg/dL
Creatinine 1.3 mg/dL
Which of the following is the most appropriate next step in management?"

Answer: Measure serum drug concentration


Context:
A 45-year-old woman is brought to the emergency department by her husband due to upper abdominal pain, nausea, and vomiting for the past couple of hours. She had similar episodes in the past, which were often precipitated by food but resolved spontaneously. Her temperature is 38.3°C (101.0°F), heart rate is 96/min, blood pressure is 118/76 mm Hg, and respiratory rate is 16/min. Physical examination reveals tenderness over the right upper quadrant that is severe enough to make her stop breathing when deeply palpated in the area. Lab results show:
Leukocyte count 18,000/mm3 with 79% neutrophils
Aspartate aminotransferase 67 IU/L
Alanine aminotransferase 71 IU/L
Serum amylase 46 U/L
Serum Lipase 55 U/L
Serum calcium 8.9 mg/dL
Ultrasonography of the abdomen is shown below. During the ultrasound exam, the patient complains of tenderness when the probe presses down on her right upper quadrant. Which of the following is the most likely cause of her pain?

Question: Which of the following is the most likely cause of her pain?

Answer: Acute calculous cholecystitis


Context:
A mother brings her 18-year-old daughter to your office because she has not menstruated yet. They recently immigrated from another country, and do not have any previous medical records. The adolescent girl looks relatively short, but otherwise looks healthy. She has no complaints except for mild intermittent lower abdominal pain for the past year. On physical examination, vitals are within normal limits. There is the presence of axillary hair, breast development, and pubic hair at Tanner stage 5. You explain to the mother and the patient that you need to perform a complete vaginal examination, however, both of them declined the procedure and would prefer that lab test be performed. Her labs are significant for the following:
FSH 7 mIU/mL
Normal values:
   Follicular phase 3.1 – 7.9 mIU/mL
   Ovulation peak 2.3 – 18.5 mIU/mL
   Luteal phase 1.4 – 5.5 mIU/mL
   Postmenopausal 30.6 – 106.3 mIU/mL
Estradiol 28 pg/mL
Normal values:
   Mid-follicular phase 27 – 123 pg/mL
   Periovulatory 96 – 436 pg/mL
   Mid-luteal phase 49 – 294 pg/mL
   Postmenopausal 0 – 40 pg/mL
Testosterone 52 ng/dL, 40 – 60 ng/dL
What is the most likely diagnosis of this patient?

Question:
Her labs are significant for the following:
FSH 7 mIU/mL
Normal values:
   Follicular phase 3.1 – 7.9 mIU/mL
   Ovulation peak 2.3 – 18.5 mIU/mL
   Luteal phase 1.4 – 5.5 mIU/mL
   Postmenopausal 30.6 – 106.3 mIU/mL
Estradiol 28 pg/mL
Normal values:
   Mid-follicular phase 27 – 123 pg/mL
   Periovulatory 96 – 436 pg/mL
   Mid-luteal phase 49 – 294 pg/mL
   Postmenopausal 0 – 40 pg/mL
Testosterone 52 ng/dL, 40 – 60 ng/dL
What is the most likely diagnosis of this patient?

Answer: Muellerian agenesis


Context: A 62-year-old woman with a pancreatic insulinoma is being prepared for a laparoscopic enucleation of the tumor. After induction of general anesthesia, preparation of a sterile surgical field, and port placement, the surgeon needs to enter the space posterior to the stomach to access the pancreatic tumor. Which of the following ligaments must be cut in order to access this space?

Question: Which of the following ligaments must be cut in order to access this space?

Answer: Gastrohepatic ligament


Context: A 55-year-old man is brought to the emergency room by his wife for severe abdominal pain for the past 1 hour. He is unable to give more information about the nature of his pain. His wife says that he has peptic ulcer disease and is being treated with antacids without a good response. She adds that he vomited repeatedly  in the last couple of hours, his vomitus being brown/red in color. His temperature is 98.6°F (37°C), respiratory rate is 16/min, pulse is 97/min, and blood pressure is 100/68 mm Hg. A physical exam reveals a tense abdomen with a board like rigidity and positive rebound tenderness. An erect abdominal x-ray is ordered. Which of the following is the most likely diagnosis?

Question: Which of the following is the most likely diagnosis?

Answer: Perforated gastric peptic ulcer


Context: A 62-year-old man presents with episodes of palpitations for the past 3 weeks. He says that he has episodes where he feels his heart is ‘racing and pounding’, lasting 1–2 hours on average. Initially, he says the episodes would happen 1–2 times per week but now happen almost every day. This last episode has been constant for the past 2 days. He denies any seizure, loss of consciousness, dizziness, chest pain, or similar symptoms in the past. His past medical history is significant for an ischemic stroke of the right anterior cerebral artery 1 month ago, status post intravenous (IV) tissue plasminogen activator (tPA) with still some residual neurologic impairment, and long-standing gastroesophageal reflux secondary to a hiatal hernia, managed medically. The patient reports a 15-pack-year smoking history, but no alcohol or recreational drug use. The vital signs include: temperature 37.0°C (98.6°F), blood pressure 100/70 mm Hg, pulse 105/min, and respiratory rate 16/min. On physical examination, muscle strength in the lower extremities is 4/5 on the left and 5/5 on the right, along with sensory loss on the left, all of which is improved from his previous exam 3 weeks ago. There is a loss of the left half of the visual field bilaterally which is stable from the previous exam. Cardiac examination is significant for a new-onset irregular rate and rhythm. No rubs, thrills or murmurs. A noncontrast computed tomography (CT) scan shows evidence of an area of infarction in the vicinity of the right anterior cerebral artery showing normal interval change with no evidence of new hemorrhage or expansion of the area of infarction. An electrocardiogram (ECG) is performed, which is shown in the exhibit (see image below). Which of the following is the most appropriate intervention to best prevent future cerebrovascular accidents (CVAs) in this patient?

Question: Which of the following is the most appropriate intervention to best prevent future cerebrovascular accidents (CVAs) in this patient?

Answer: Begin warfarin and heparin


Context: In 2005, a group of researchers believed that prophylactically removing the ovaries and fallopian tubes (bilateral salpingo-oophorectomy) in BRCA-mutation positive women would reduce the chance that they developed breast cancer. To test this hypothesis, they reviewed a database of women who were known to be BRCA-mutation positive and divided the group into those with breast cancer and those without breast cancer. They used data in the registry and surveys about peoples’ surgical history to compare the proportion of each population that had undergone a bilateral salpingo-oophorectomy. Based on this data, they reported that women undergoing the procedure had a lower chance of developing breast cancer later in life with an odds ratio of 0.46. This is an example of what type of study design?

Question: This is an example of what type of study design?

Answer: Case-control


Context: A 64-year-old man with a history of type 2 diabetes mellitus is referred to a urologist. The patient has had pain when urinating and difficulty starting a stream of urine for over 4 months now. He is bothered because he has to urinate about 9 times every day, including several times when he wakes up at night. A digital rectal examination revealed multiple hard nodules in the prostate gland. A CT scan shows a nodule in the right lung that measures 3 cm. An ultrasound scan of his urinary bladder and prostate shows residual urine of > 200 mL and heterogeneous findings of the prostate gland. Biopsy reveals grade 2 prostate adenocarcinoma. Follow-up 9 months later shows his prostate cancer is well controlled with goserelin. If one considers pulmonary nodules that are the same size as this patient’s, which of the following additional findings on CT scans would most likely prompt the removal of such nodules?

Question: If one considers pulmonary nodules that are the same size as this patient’s, which of the following additional findings on CT scans would most likely prompt the removal of such nodules?

Answer: Extending fine striations