USMLE-STEP-2 Online Practice Questions and Answers

A60-year-old man presents with a nonproductive cough for a week and generalized malaise. He also has noted some abdominal pain associated with diarrhea for the past few days. His temperature is 101.5°F a nd clinical examination is unremarkable. ACXR shows a left lower lobe infiltrate. His urinalysis shows 50 RBCs, and his BUN (30) and creatinine (1.6) are both mildly elevated. In light of the extrapulmonary symptoms and signs, which of the following is the most likely cause of his pneumonia?

A. Pseudomonas aeruginosa

B. S. aureus

C. H. influenzae

D. S. pneumoniae

E. Legionella

A 2-month-old infant is brought to the emergency department with irritability and lethargy. The parents state that he was well until he rolled off the couch on to the floor yesterday. On examination, he is inconsolable and afebrile. The fontanels are full and tense. He has a generalized tonic-clonic seizure. Which of the following is the most important initial diagnostic study to order?

A. serum calcium, phosphorus, and magnesium levels

B. analysis of cerebrospinal fluid (CSF)

C. cranial computed tomography (CT) scan

D. serum ammonia level

E. serum acetaminophen level

Routine examination of an otherwise healthy kindergarten child with a history of asthma reveals a BP of 140/90 mmHg. Which of the following is the most likely cause of the hypertension?

A. theophylline toxicity

B. chronic lung disease

C. renal disease

D. coarctation of the aorta

E. obesity

A4-year-old child with grade III vesicoureteral reflux has recurrent UTIs despite adequate antibiotic prophylaxis. Which of the following is the most appropriate next step in the treatment of this patient?

A. IV antibiotic treatment for 2 weeks

B. repeat renal scan

C. renal arteriogram

D. antireflux surgery

E. addition of vitamin C (ascorbic acid) tothe treatment regimen

Repeated thunderstorms have resulted in overflow of municipal wastewater treatment plants by floodwaters. Volunteer sandbaggers downstream from the plants developed health concerns when the overflow became evident. As a public health officer you are asked to evaluate the situation. Which of the following is your most important recommendation to workers in order to prevent illness from exposure to the contaminated water?

A. Do careful hand washing before meals and cigarette smoke breaks.

B. Boil all water that is to be used for drinking or cooking.

C. Offer hepatitis A vaccinations to al work crews prior to the next disaster.

D. Start prophylaxis with a broad-spectrum antibiotic for all workers who do not have a contraindication.

E. Offer oral polio vaccine to all eligible workers.

A 58-year-old woman with a history of chronic paranoid schizophrenia, who has been continuously treated with antipsychotics for the past 20 years, lives in a community-based residential facility. She has recently suffered an increase in auditory hallucinations, and her haloperidol dose has been increased from 2.5 to 10 mg/day. Four days later, she is brought by a visiting nurse to the emergency room, where she presents with confusion, marked flexor and extensor rigidity in her legs and arms, and a temperature of 103.5°F. Her blood pressure is160/120 mmHg, her pulse is 120/min and irregular. Which of the following is the most important laboratory test to evaluate the possibility of the diagnosis?

A. serum creatine phosphokinase (CPK) level

B. serum sodium level

C. serum potassium level

D. serum glucose level

E. serum calcium level

A 35-year-old woman is seen by her primary care physician for a physical examination. She tells him she has a twin brother who has bipolar disorder and has been worried that she will develop it. Which of the following would be most helpful for her to hear?

A. "You're past the age when bipolar disorder develops, so don't worry about it."

B. "There is no clear evidence that a bipolar disorder is genetically determined."

C. "The concordance rate for bipolar disorder for dizygotic twins is 19%."

D. "The concordance rate for bipolar disorder for dizygotic twins is 79%."

E. "Prophylactic treatment with lithium is advisable."

A 65-year-old man presents to the emergency department with sudden onset of pain and weakness of the left lower extremity of 2-hour duration. Past history reveals chronic atrial fibrillation following a myocardial infarction 12 months ago. On examination, he is found to have a cool, pale left lower extremity with decreased strength and absent popliteal and pedal pulses. The opposite leg has a normal appearance with palpable pulses.

Following successful treatment for an embolus to the left femoral artery with no evidence of a reperfusion injury, which of the following long-term treatments would most likely decrease the chance of recurrent embolus?

A. anticoagulation

B. exercise program

C. coronary artery bypass grafting

D. aortofemoral bypass grafting

E. placement of a vena cava filter

A 45-year-old man presents to the physician's office complaining of dysphagia and retrosternal pressure and pain of 2-year duration. The symptoms have worsened over the last 3 months. He has a 30 packyear smoking history and drinks beer on weekends. Vital signs include a BP of 150/90 mmHg, pulse rate of 90/ min, and respiratory rate of 12/min, with a normal temperature. Examination reveals a thin man with a normal heart, lung, and abdomen examination. An esophagogram reveals a 6-cm, smooth, concave defect in the midesophagus with sharp borders. Esophagoscopy reveals intact overlying mucosa and a mobile tumor. Which of the following is the most likely diagnosis?

A. esophageal carcinoma

B. bronchogenic carcinoma with invasion of the esophagus

C. benign esophageal polyp

D. leiomyoma

E. lymphoma

A previously healthy 45-year-old woman is involved in a motor vehicle crash, sustaining multiple rib fractures, a complex duodenal injury, and a fractured pelvis. She is ventilated in the ICU. Because of a persistent high-output duodenal fistula, the patient has required prolonged parenteral alimentation. During her ICU course, the patient develops diarrhea, mental depression, alopecia, and perioral and periorbital dermatitis. Administration of which of the following trace elements are most likely to reverse these complications?

A. iodine

B. zinc

C. selenium

D. silicon

E. tin