USMLE USMLE Certifications USMLE-STEP-2 Questions & Answers

• Question 691:

  For each item, select the ONE best lettered option that is most closely associated with it. Each lettered heading may be selected once, more than once, or not at all. A 47-year-old man complains of fatigue and dizziness. On laboratory evaluation, he is noted to have significant hyponatremia and hyperkalemia.

  A. Cushing's syndrome

  B. Addison's disease

  C. Klinefelter syndrome

  D. hyperparathyroidism

  E. hypothyroidism

  F. pheochromocytoma

  G. acromegaly

  H. diabetes insipidus

  I. diabetes mellitus

  J. polycystic ovarian disease

  Correct Answer: B

  Addison disease, or primary adrenocortical deficiency, commonly results in a low serum Na+, a low serum Cl-, and a high serum K+. Aldosterone deficiency causes loss of sodium in the urine and contributes to the hyperkalemia. The original description of Addison disease summarizes well the key clinical findings: general languor and debility, feebleness of the heart's action, irritability of the stomach, and a peculiar change of the color of the skin. The hyperpigmentation of the skin is often seen on the elbows and in the creases of the hands.

• Question 692:

  For each item, select the ONE best lettered option that is most closely associated with it. Each lettered heading may be selected once, more than once, or not at all. A 55-year-old woman is having episodic palpitations, headaches, and sweating. On examination, her BP is elevated.

  A. Cushing's syndrome

  B. Addison's disease

  C. Klinefelter syndrome

  D. hyperparathyroidism

  E. hypothyroidism

  F. pheochromocytoma

  G. acromegaly

  H. diabetes insipidus

  I. diabetes mellitus

  J. polycystic ovarian disease

  Correct Answer: F

  Pheochromocytoma is a secondary cause of hypertension. Pheochromocytomas secrete catecholamines; 80% are unilateral, solitary tumors, most often located in the adrenal gland. Patients present with episodes of headache, palpitations, sweats, and a sense of apprehension.

• Question 693:

  For each item, select the ONE best lettered option that is most closely associated with it. Each lettered heading may be selected once, more than once, or not at all. A 42-year-old obese woman complains of hirsutism, amenorrhea, and difficulty becoming pregnant.

  A. Cushing's syndrome

  B. Addison's disease

  C. Klinefelter syndrome

  D. hyperparathyroidism

  E. hypothyroidism

  F. pheochromocytoma

  G. acromegaly

  H. diabetes insipidus

  I. diabetes mellitus

  J. polycystic ovarian disease

  Correct Answer: J

  Polycystic ovarian syndrome is characterized by infertility, hirsutism, obesity, and amenorrhea or oligomenorrhea. These patients have chronic anovulation and experience withdrawal bleeding after progestogen administration.

• Question 694:

  A 45-year-old woman presents with fever, anorexia, nausea, and diarrhea. Other patients in the community have presented similarly and have a common exposure at a local restaurant. In the above case of hepatitis, select the most likely type of viral hepatitis.

  A. hepatitis A

  B. hepatitis B

  C. hepatitis C

  Correct Answer: A

  Hepatitis A is transmitted almost exclusively by the fecal-oral route. Large outbreaks have been linked to contaminated food products. Intrafamily and intrainstitutional spread also is common. Clinical severity usually is mild, and hepatitis A does not progress to chronicity. Hepatitis C more commonly progresses to chronicity (5070% develop chronic hepatitis and 8090% of these patients have evidence for chronic infection). Hepatitis C can lead to cirrhosis and hepatocellular carcinoma. Chronicity occurs in only 110% of patients with hepatitis B.

• Question 695:

  A 43-year-old prison cook becomes ill with jaundice, malaise, and fever. Shortly thereafter, multiple prison

  inmates develop similar symptoms.

  According to the above symptoms, select the most likely type of viral hepatitis.

  A. hepatitis A

  B. hepatitis B

  C. hepatitis C

  Correct Answer: A

  Hepatitis A is transmitted almost exclusively by the fecal-oral route. Large outbreaks have been linked to contaminated food products. Intrafamily and intrainstitutional spread also is common. Clinical severity usually is mild, and hepatitis A does not progress to chronicity. Hepatitis C more commonly progresses to chronicity (5070% develop chronic hepatitis and 8090% of these patients have evidence for chronic infection). Hepatitis C can lead to cirrhosis and hepatocellular carcinoma. Chronicity occurs in only 110% of patients with hepatitis B

• Question 696:

  A 46-year-old woman presents with a 4-hour history of left flank pain with fever and chills. On examination, her temperature is 103°F, pulse rate is 120/min, re spiratory rate is 40/min, and supine BP is 80/40 mmHg. She has marked tenderness over the left flank and left upper quadrant of the abdomen without rebound. Urinalysis shows multiple red blood cells (RBCs), multiple WBCs, and WBC casts.

  Which of the following is the most likely diagnosis?

  A. appendicitis

  B. pyelonephritis

  C. cholelithiasis

  D. diverticulitis

  E. pelvic inflammatory disease

  Correct Answer: B

  Detection of leukocyte casts is pathognomonic for pyelonephritis. Common symptoms include fever, shaking chills, nausea, vomiting, and diarrhea. Flank tenderness over the affected kidney is very common

• Question 697:

  A 55-year-old man complains of severe headaches over the past few weeks. Similar episodes have occurred in past years. Which of the following supports the diagnosis of cluster headaches?

  A. Pain-free intervals can last for days and then recur.

  B. Attacks of daily pain last for 48 weeks.

  C. The most common location of pain is occipital.

  D. Women are affected twice as commonly as men.

  E. Caffeine is the most effective treatment for an acute attack.

  Correct Answer: B

  Men are affected by cluster headaches seven to eight times more often than women. Attacks are typically periorbital and may involve the temporal area. Cluster headaches typically occur daily over a 4- to 8-week period followed by pain-free intervals averaging 1 year. The periodicity of the attacks is often striking, with daily recurrences of pain often at the same hour. Pathogenesis is thought to be due to abnormal serotonergic neurotransmission. One hundred percent oxygen inhalation is most effective acutely. Drugs used to prevent cluster attacks include lithium, ergotamine, sodium valproate, and prednisone.

• Question 698:

  A 72-year-old man has the sudden onset of suprapubic pain and oliguria. His temperature is 38.0°C (100.4°F), pulse is 100/min, respiration rate is 12 /min, and BP is 110/72 mmHg. Abdominal examination is remarkable only for a tender, distended urinary bladder.

  Which of the following is the most likely cause of this condition?

  A. urinary tract infection

  B. prostatic hypertrophy

  C. posterior urethral valves

  D. renal carcinoma

  E. renal arterial occlusion

  Correct Answer: B

  Acute oliguria is a medical emergency requiring the immediate identification of any correctable cause. Distention of the urinary bladder indicates bladder outlet obstruction. Immediate management should be the passage of a urethral catheter to relieve the obstruction and provide urine for examination. An abdominal flat plate, ultrasonography, or IVP may yield a diagnosis but delay the relief of obstruction. Furosemide may be harmful if given while the bladder is obstructed. Bladder outlet obstruction may be caused by prostatic hypertrophy or prostatitis, stones, clots, malignancy, or urethral stricture; it may also be neurogenic. Posterior urethral valves are a congenital defect that could cause obstruction in children but rarely in adults. Renal carcinoma would not cause outlet obstruction. Renal arterial occlusion can cause acute renal failure but not obstructive uropathy. If urethral catheterization fails to relieve the obstruction, further evaluation, including radiographic or ultrasound studies, is in order. Suprapubic cystostomy may be necessary to empty the bladder.

• Question 699:

  A 42-year-old woman is noted to have a multinodular goiter on examination. She has no symptoms and is clinically euthyroid. Which of the following statements about Hashimoto's thyroiditis is true?

  A. The condition is associated with prior radioactive exposure.

  B. Patients diagnosed with this disorder have an increased incidence of thyroid cancer.

  C. Corticosteroids are helpful in controlling the progression of the disease.

  D. Antinuclear antibodies are pathognomonic for this disease.

  E. Hashimoto's thyroiditis is an autoimmune disease.

  Correct Answer: E

  Hashimoto's thyroiditis, an autoimmune condition, is the leading cause of multinodular goiter in the United States. Although not unique to this condition, antimicrosomal antibodies are found in 7095% of patients. Antinuclear antibodies are associated with SLE. Although an autoimmune process, steroids are of no benefit in this condition. One-third of patients experience progressive loss of glandular function, and eventually become hypothyroid, but there is no increased incidence of thyroid cancer

• Question 700:

  A 72-year-old man has the sudden onset of suprapubic pain and oliguria. His temperature is 38.0°C (100.4°F), pulse is 100/min, respiration rate is 12 /min, and BP is 110/72 mmHg. Abdominal examination is remarkable only for a tender, distended urinary bladder. Which of the following is the most appropriate immediate management of this patient?

  A. plain x-ray of the abdomen

  B. abdominal ultrasonography

  C. urethral catheter

  D. IV furosemide

  E. intravenous pyelogram (IVP)

  Correct Answer: C

  Acute oliguria is a medical emergency requiring the immediate identification of any correctable cause. Distention of the urinary bladder indicates bladder outlet obstruction. Immediate management should be the passage of a urethral catheter to relieve the obstruction and provide urine for examination. An abdominal flat plate, ultrasonography, or IVP may yield a diagnosis but delay the relief of obstruction. Furosemide may be harmful if given while the bladder is obstructed. Bladder outlet obstruction may be caused by prostatic hypertrophy or prostatitis, stones, clots, malignancy, or urethral stricture; it may also be neurogenic. Posterior urethral valves are a congenital defect that could cause obstruction in children but rarely in adults. Renal carcinoma would not cause outlet obstruction. Renal arterial occlusion can cause acute renal failure but not obstructive uropathy. If urethral catheterization fails to relieve the obstruction, further evaluation, including radiographic or ultrasound studies, is in order. Suprapubic cystostomy may be necessary to empty the bladder.