CK- NBME 11 – Block 2

A 67-year-old man is brought to the emergency department because of a 6-week history of moderate pain in his legs when walking. He says the pain begins after he walks approximately 50 feet; it improves if he stops walking but returns when he tries to move again. He says the pain is worse in his right leg. He has hypertension and hyperlipidemia. His medications are lisinopril, amlodipine, metoprolol, and atorvastatin. He has smoked two packs of cigarettes daily for 40 years. He appears in no acute distress. He is 180 cm (5 ft 11 in) tall and weighs 107 kg (235 lb); BMI is 33 kg/m2. His blood pressure is 150/86 mm Hg. Examination shows sparse hair from 6 cm above the foot to the dorsum of the foot bilaterally. Lower extremity pulses are 1 +. At this time, it is most appropriate to evaluate this patient for which of the following conditions?

A 52-year-old man comes to the physician 2 weeks after he noted yellowing of his skin, which has since resolved spontaneously. He has hypertension and osteoarthritis. His medications are hydrochlorothiazide and tramadol. He uses intravenous heroin weekly; his last injection was 2 days ago. He is 175 cm (5 ft 9 in) tall and weighs 79 kg (175 lb); BMI is 26 kg/m2. His temperature is 37°C (98.6°F), pulse is 78/min, respirations are 12/min, and blood pressure is 148/92 mm Hg. Examination shows no abnormalities. Serum studies show:

Bilirubin: 2.4 mg/dL

Alkaline phosphatase: 118 U/L

AST: 250 U/L

ALT: 300 U/L

Hepatitis A antibody: negative

HBsAg: negative

HBsAb: negative

Anti-HCV: negative

Which of the following is most likely to confirm the diagnosis?

A 52-year-old man comes to the physician because of a 3-month history of increasing difficulty with swallowing. He first noted difficulty swallowing solids; during the past 3 weeks, he has had difficulty swallowing fluids. He has had an 18-kg (40-lb) weight loss during this time. He has not had heartburn or nasal regurgitation of fluids. He has no history of serious illness and takes no medications. He has smoked one and one-half packs of cigarettes daily for 34 years and drinks 16 oz of vodka three times weekly. The patient is 180 cm (5 ft 11 in) tall and weighs 68 kg (150 lb); BMI is 21 kg/m2. He appears cachetic. Examination shows no other abnormalities. A percutaneous endoscopic gastrostomy tube is placed, and enteral nutrition is begun. During the next 36 hours, this patient is at increased risk for which of the following laboratory abnormalities?

A 19-year-old woman with celiac disease comes to the physician because of a 3-month history of daily diffuse aching in her arms and legs. She has not had weakness or numbness. She continues to have diarrhea approximately 3 days weekly. She tries to avoid eating gluten but has found it difficult to maintain an entirely gluten-free diet. Her medications are ferrous sulfate and an oral contraceptive. Her last examination was 2 years ago. She appears tired. She is 170 cm (5 ft 7 in) tall and weighs 54 kg (120 lb); BMI is 19 kg/m2. Her pulse is 67/min, and blood pressure is 105/72 mm Hg. The abdomen is soft, mildly tender, and nondistended; there is no rebound, guarding, or masses. There is mild weakness of the hip flexors and extensors. Serum studies show:

Na⁺ (Sodium): 137 mEq/L

K⁺ (Potassium): 3.9 mEq/L

Cl⁻ (Chloride): 105 mEq/L

HCO₃⁻ (Bicarbonate): 22 mEq/L

Ca²⁺ (Calcium): 8.4 mg/dL

Urea nitrogen (BUN): 20 mg/dL

Creatinine: 0.8 mg/dL

Phosphorus: 2.7 mg/dL

Alkaline phosphatase: 175 U/L

Parathyroid hormone (intact): 870 pg/mL

25-Hydroxyvitamin D: 7 ng/mL (N >20 ng/mL)

Which of the following is the most likely diagnosis?

 A 57-year-old woman comes to the emergency department because of a 6-month history of productive cough that has worsened during the past week. During the past 6 weeks, she also has had progressive shortness of breath, fatigue, and sputum production. She has had four episodes of pneumonia during the past 3 years. She takes no medications. She appears ill. Her temperature is 38.4°C (101°F), pulse is 96/min, and respirations are 22/min. Diffuse crackles and rhonchi are heard bilaterally. The remainder of the examination shows no abnormalities. A chest x-ray shows linear atelectasis and dilated and thickened airways. Which of the following is the most appropriate next step in management?

A 77-year-old man with hyperlipidemia comes to the physician because of a 3-day history of “turning yellow.” During the past 4 weeks, he also has had a 2.3-kg (5-lb) weight loss despite no change in appetite. He says he feels well. He has not had abdominal pain, nausea, vomiting, or changes in bowel movements. His medications are atorvastatin and daily aspirin. He is 180 cm (5 ft 11 in) tall and weighs 79 kg (175 lb); BMI is 24 kg/m2. His pulse is 80/min and regular, and blood pressure is 130/75 mm Hg. Examination shows jaundice and scleral icterus. There is a palpable, nontender gallbladder; there is no hepatosplenomegaly, and no abdominal masses are noted. Rectal examination shows no masses. Test of the stool for occult blood is negative. Which of the following is the most likely diagnosis?

A 17-year-old boy comes to the physician for an examination prior to participation in school sports. He feels well. He has no history of concussions or musculoskeletal injuries. He has never fainted with exercise. He has no history of serious illness and takes no medications. There is no family history of unexplained or cardiac death in adults younger than 50 years. The patient appears well. He is 188 cm (6 ft 2 in) tall and weighs 65 kg (143 lb); BMI is 18 kg/m2. His arm span is 200 cm (6 ft 6 in). Vital signs are within normal limits. The upper-to-lower body ratio is decreased. Examination shows a long, thin face and large ears. The sclerae are blue, but the retina can be visualized without difficulty. The upper extremities are thin. Examination of the chest shows pectus carinatum. No murmurs are heard on cardiac examination; S1 and S2are normal. Peripheral pulses are normal. Which of the following is the most appropriate next step in evaluation prior to providing clearance for this patient to participate in sports?

 A previously healthy 1 -year-old boy is brought to the emergency department by his mother because of a 3-day history of fever, fussiness, and poor feeding. He was born at 38 weeks’ gestation and delivered by a midwife at home. His mother received no prenatal care. Immunizations are up-to-date. On arrival, the patient is irritable but consolable and does not appear toxic. His temperature is 40°C (104°F), pulse is 140/min, and respirations are 40/min. Capillary refill time is 2 seconds. The anterior fontanel is open, soft, and flat. The mucous membranes are moist. Examination shows no other abnormalities. Urinalysis shows:

pH: 6.0

Specific gravity: 1.005

Blood: 1+

Protein: 1+

RBC: 10 /hpf

WBC: >100 /hpf

Nitrites: negative

Leukocyte esterase: positive

Results of a complete blood count, serum studies, and blood and urine cultures are pending. Which of the following is the most appropriate next step in diagnosis?

A 56-year-old man comes to the physician with his wife because of a 2-year history of increasing restlessness while he is asleep. His wife reports that he kicks his legs and swings his arms several times during the night. He appears to be asleep during these episodes, and he typically says that he was dreaming if awakened during an episode. His wife now sleeps in a separate bed after he hit her during one of the episodes 1 year ago. He has a 3-year history of mild depression treated with weekly psychotherapy. He takes no medications. He does not smoke cigarettes, drink alcohol, or use illicit drugs. Examination shows an occasional mild, rhythmic, involuntary shaking of the right hand that is most noticeable when the hand is in his lap. This patient is at greatest risk for developing which of the following conditions?

A 16-year-old boy is brought to the emergency department 15 minutes after involvement in a motor vehicle collision. He was the restrained driver. His car crashed into the car in front of him, then was hit from behind by a pickup truck. The patient’s car was destroyed, but he was able to walk away from the scene of the collision. On arrival, he is upset and reports moderate chest pain. His pulse is 100/min, respirations are 20/min, and blood pressure is 130/80 mm Hg. Examination shows erythema over the chest in the area where his seat belt had been fastened. No other abnormalities are noted. Serum studies show:

Creatine kinase (CK), total: 221 U/L

CK-MB fraction: 20% (normal <5% of total CK)

Troponin I: 1 ng/mL (normal <0.1)

Troponin T: 0.3 ng/mL (normal <0.1)

Chest x-rays show no abnormalities. An ECG shows a normal sinus rhythm and nonspecific T-wave inversion in leads V3 through V6. Which of the following is the most appropriate next step in management?

 A state health department is alerted to a potential outbreak of hepatitis A during the past 2 weeks involving a restaurant in a city with a population of 350,000. After a preliminary descriptive analysis, including case identification, the health department matches cases with control subjects and examines foods that are potential sources of infection. Which of the following is the most appropriate statistical analysis for the investigators to determine the source of this outbreak?

A 52-year-old man is brought to the emergency department because of a 6-hour history of thirst and fatigue and a 2-hour history of light-headedness. He has been working outside during the past 2 days in temperatures reaching 90.0°F. He has no history of serious illness and takes no medications. On arrival, he is lethargic. He is oriented to person but not to place or time. His temperature is 37.2°C (99.0°F), pulse is 74/min and irregular, respirations are 16/min, and blood pressure is 95/64 mm Hg. The lungs are clear to auscultation. No bruits are heard. No murmurs are heard on cardiac examination. The abdomen is nontender. ECG is shown. In addition to intravenous administration of fluids, which of the following is the most appropriate next step in management?

A previously healthy 19-year-old man comes to the physician because of a 3-day history of an increasingly severe bilateral headache and a 1 -day history of fever and diarrhea. He says he feels sore all over. Use of acetaminophen has not relieved his headache. He is a college student and lives in a dormitory. He is in moderate distress and closes his eyes when lights are turned on. His temperature is 38°C (100.4°F), pulse is 100/min, respirations are 22/min, and blood pressure is 120/70 mm Hg. Examination shows dry mucous membranes and nuchal rigidity. Funduscopic examination shows no abnormalities. Neurologic examination, including mental status examination, shows no abnormalities. His serum glucose concentration is 90 mg/dL. A CT scan of the head without contrast shows no abnormalities. A lumbar puncture is performed. Cerebrospinal fluid analysis shows a glucose concentration of 70 mg/dL, a protein concentration of 35 mg/dL, and a leukocyte count of 50/mm3 (100% monocytes). Which of the following is the most likely diagnosis?

An 82-year-old man is brought to the emergency department because of a 2-hour history of progressive shortness of breath. He has not had chest pain, fever, chills, or cough. He has coronary artery disease, essential hypertension, and hypercholesterolemia. Three years ago, he underwent uncomplicated coronary artery bypass grafting. His medications are clopidogrel, enalapril, rosuvastatin, and daily aspirin. He smoked one and one-half packs of cigarettes daily for 59 years but quit 3 years ago. He drinks two glasses of wine daily. His temperature is 37°C (98.6°F), pulse is 90/min and regular, respirations are 26/min, and blood pressure is 118/78 mm Hg. Examination shows jugular venous distention. Crackles are heard in the lung bases; scattered expiratory wheezes are heard in all lung fields. On cardiac examination, an S3 gallop is heard. There is 2+ pretibial and 3+ pedal edema bilaterally. A chest x-ray shows bilateral pulmonary infiltrates, prominent hilar vascularity, and cardiomegaly. Which of the following is most likely to be decreased in this patient?

A 67-year-old woman comes to the office for evaluation 2 weeks before a scheduled right total hip replacement under general anesthesia. She has a 20-year history of rheumatoid arthritis. Current medications are methotrexate, prednisone, and leflunomide. On examination, any movement of the right hip causes pain. Results of laboratory studies are within the reference ranges. In addition to a chest x-ray and posteroanterior and lateral x-rays of the right hip, which of the following is the most appropriate imaging study before the operation?

 A 30-year-old man is brought to the emergency department 30 minutes after a 20-second generalized tonic-clonic seizure. He has a 3-week history of early morning projectile vomiting, headache, and blurred vision. On arrival, he is mildly lethargic. He has no history of serious illness and takes no medications. His father died of brain cancer at the age of 45 years. The patient has no known sick contacts. He does not smoke cigarettes or drink alcohol. His temperature is 37°C (98.6°F), pulse is 92/min, respirations are 18/min, and blood pressure is 138/98 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 98%. Finger-nose testing shows dysmetria. There is decreased rapid alternating movement of the hands. His gait is unsteady. An MRI of the brain shows a vascular tumor in the posterior fossa and ventriculomegaly of the third and lateral ventricles. Which of the following tests is most likely to reveal a second tumor with the same genetic abnormality?

A 19-year-old woman is admitted to the hospital because of a 6-day history of severe abdominal pain and bloody diarrhea. She has no history of serious illness. Her temperature is 37.8°C (100°F), pulse is 75/min, respirations are 26/min, and blood pressure is 120/70 mm Hg. Abdominal examination shows no distention; there is mild tenderness to palpation. Laboratory studies show:

Hemoglobin: 9.2 g/dL

Reticulocyte count: 5.4%

Platelet count: 17,000/mm³

Serum:

Total bilirubin: 2.5 mg/dL

Haptoglobin: 8.2 mg/dL (normal 40–265)

Lactate dehydrogenase (LDH): 4285 U/L

Which of the following is the most likely infectious agent?

 A 26-year-old nulligravid woman comes to the clinic because of a 6-week history of a mildly painful lump in her right breast. She has no history of serious illness or operative procedures. She takes no medications. Her paternal aunt was diagnosed with invasive breast cancer at the age of 65 years and underwent successful treatment with mastectomy and chemotherapy. A well-circumscribed, mildly tender, 1.5-cm mass is palpated in the upper outer quadrant of the patient’s right breast, approximately 4 cm from the nipple. No other abnormalities are noted. Which of the following is the most appropriate next step in management?

 A 32-year-old man who is in the US Marine Corps is being discharged from the hospital after sustaining injuries 2 weeks ago in Southwest Asia when a rocket exploded a few yards away from him. He sustained fragmentation wounds to the right upper extremity, abdomen, and lower extremities bilaterally. At the time of injury, he received a dose of tetanus toxoid and underwent debridement and irrigation of his soft tissue wounds. Exploratory laparotomy showed a hepatic laceration and splenic laceration requiring splenectomy. He has no other history of major medical illness and takes no medications. He does not smoke. He drinks four 12-oz beers every weekend. Today, he reports no concerns. Vital signs are within normal limits. Physical examination shows a well-healing midline abdominal incision and well-healing wounds over the right upper and lower extremities. Which of the following is the most appropriate vaccination for this patient at this time?

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A 55-year-old woman comes to the office because of a 6-month history of cough productive of yellow sputum and a 1-week history of intermittent bloody streaks in her sputum. She also reports occasional night sweats during the past 3 months and an unintentional weight loss of 4.5 kg (10 lb) during the past year. She has not had fever, chills, chest pain, or shortness of breath. Medical history is notable for scoliosis and gastroesophageal reflux disease. Her only medication is omeprazole. She does not smoke cigarettes. She is 155 cm (5 ft 1 in) tall and weighs 40 kg (88 lb); BMI is 17 kg/m2. Temperature is 36.5°C (97.7°F), pulse is 102/min, respirations are 18/min, and blood pressure is 110/61 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 98%. Auscultation of the lungs shows inspiratory crackles in the anterior right mid lung field. Musculoskeletal examination shows marked scoliosis. The remainder of the examination shows no abnormalities. X-ray of the chest shows multiple nodules in the left lower lobe. CT scan of the chest is shown. Which of the following is the most appropriate next step in management?