STEP2 Exam Questions and Answers | Exam-Dumps (Page: 8)

QUESTION: 36

A 58-year-old man is establishing care with you because his insurance changed. His old records have not yet arrived, but he is complaining of palpitations and lightheadedness, so you order the ECG shown in Figure

Which of the following is the most likely problem associated with this pattern?

congenital heart disease
severe aortic valve disease
hypokalemia
atrial septal defect (ASD)
VSD

Answer(s): B

Explanation:

The prolonged, negative QRS vector anteriorly (V1-V3) and wide notched R waves in V5 and V6 are characteristic for LBBB. In RBBB, there is an rSR' complex in V1 and QRS pattern in V6. Accelerated junctional rhythm would not have P waves. Partial blocks, such as left anterior fascicular block, generally do not prolong the QRS duration substantially, but are associated with shifts in the frontal plane QRS axis (left axis deviation). With intraventricular conduction delay, the QRS is between 100 and 120 ms. LBBB is a marker of one of four conditions: severe aortic valve disease, ischemic heart disease, long-standing hypertension, and cardiomyopathy. RBBB is seen more commonly than LBBB in patients without structural heart disease, although RBBB also occurs with congenital heart disease and ASD or valvular heart disease. Hyper- but not hypokalemia may cause intraventricular conduction delay. Myocarditis does not usually lead to LBBB.

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QUESTION: 37

In a patient infected with HIV, which of the following laboratory parameters provides the most useful information about the current immunologic status of the patient?

HIV RNA level
white blood cell (WBC) count
CD4+ T-cell count
CD8+ T-cell count
p24 antigen level

Answer(s): C

Explanation:

The CD4+ T-cell count provides information on the current immunologic status of a patient infected with HIV. HIV RNA level measures viral load and predicts what will happen to the CD4+ count in the near future.
WBC count is a nonspecific marker for infection. The p24 antigen assay is used for direct detection of HIV.
CD8+ count typically is not as important in monitoring immunologic status though the CD4+/CD8+ ratio sometimes is used

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QUESTION: 38

During a routine checkup, a 45-year-old executive is found to have hypercalcemia. Subsequent workup reveals elevated parathormone, decreased phosphorus, elevated chloride, and normal blood urea nitrogen (BUN), and creatinine in serum. Urinary calcium is above normal levels. What is the most likely etiology?

multiple myeloma
primary hyperparathyroidism
hypervitaminosis D
sarcoidosis
milk alkali syndrome

Answer(s): B

Explanation:

Primary hyperparathyroidism is characterized by hypercalcemia, hypophosphatemia, hyperchloremia, increased urinary calcium excretion, and an increase in serum parathormone level. Multiple myeloma is associated with hypercalcemia when there are many lytic lesions. Chronic ingestion of 50100 times the normal requirement of vitamin D is required to produce hypercalcemia in normal people, so hypervitaminosis D is rare and parathormone levels would be suppressed. With milk alkali syndrome, which is caused by excess ingestion of calcium and absorbable antacids, parathormone levels would also be suppressed. In sarcoidosis, about 10% of patients have hypercalcemia attributable to increased intestinal absorption of calcium and increased production of 1,25(OH)2D.

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QUESTION: 39

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?

plain x-ray of the abdomen
abdominal ultrasonography
urethral catheter
IV furosemide
intravenous pyelogram (IVP)

Answer(s): C

Explanation:

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.

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QUESTION: 40

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?

urinary tract infection
prostatic hypertrophy
posterior urethral valves
renal carcinoma
renal arterial occlusion

Answer(s): B

Explanation:

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.

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USMLE STEP2 Exam (page: 8) USMLE Step2 Updated on: 25-Dec-2025

QUESTION: 36

Explanation:

QUESTION: 37

Explanation:

QUESTION: 38

Explanation:

QUESTION: 39

Explanation:

QUESTION: 40

Explanation:

USMLE STEP2 Exam (page: 8)
USMLE Step2
Updated on: 25-Dec-2025