CORRECT ANSWERS WITH RATIONALE NEW UPDATE OF THIS
YEAR ALREADY GRADED A+
1. A 72-year-old male presents with sudden-onset severe low back pain and
bilateral lower extremity weakness. His past medical history is significant for
hypertension and benign prostatic hyperplasia. On examination, he has absent anal
sphincter tone and a palpable, distended bladder. Which of the following is the
most appropriate next step?
A) Prescribe oral corticosteroids and schedule an MRI in 2 weeks
B) Administer a course of physical therapy for core strengthening
C) Obtain an urgent MRI of the lumbar spine without contrast
D) Prescribe high-dose nonsteroidal anti-inflammatory drugs and recommend bed
rest
E) Schedule a transrectal ultrasound of the prostate
Answer: C
Rationale: This patient presents with cauda equina syndrome, characterized by
acute low back pain, bilateral leg weakness, saddle anesthesia (implied by absent
anal tone), and urinary retention. This is a surgical emergency. The most
appropriate next step is an urgent MRI of the lumbar spine to identify the
compressive lesion (e.g., herniated disc or tumor) requiring decompression.
Delaying imaging or treating conservatively with NSAIDs, physical therapy, or
prostate imaging would be inappropriate and could lead to permanent neurological
damage.
2. A 45-year-old female with systemic lupus erythematosus complains of
progressive shortness of breath and a nonproductive cough over the past 3 months.
A chest x-ray shows a small left-sided pleural effusion and blunting of the left
costophrenic angle. A diagnostic thoracentesis yields exudative fluid with a
glucose level of 35 mg/dL and a positive antinuclear antibody (ANA) titer of
1:640. Which of the following is the most likely diagnosis?
A) Parapneumonic effusion
B) Malignant pleural effusion
,C) Lupus pleuritis
D) Tuberculous pleurisy
E) Pulmonary embolism with infarction
Answer: C
Rationale: In a patient with known SLE, the presence of a pleural effusion that is
exudative and has a low glucose with a positive ANA in the pleural fluid is highly
suggestive of lupus pleuritis. While parapneumonic effusions and tuberculosis can
also cause exudative effusions with low glucose, the positive ANA in the pleural
fluid in the context of SLE points directly to the underlying autoimmune process as
the cause.
3. A 68-year-old male with a history of type 2 diabetes and coronary artery disease
presents with a painful, red, swollen right great toe. He reports that the pain started
suddenly last night and is so severe that even the bedsheet touching it is
unbearable. His temperature is 38.2°C (100.8°F). Laboratory studies reveal a
serum uric acid level of 9.2 mg/dL. Which of the following is the most appropriate
initial pharmacologic treatment?
A) Allopurinol 300 mg daily
B) Febuxostat 40 mg daily
C) Colchicine 1.2 mg followed by 0.6 mg one hour later
D) Prednisone 10 mg daily
E) Probenecid 500 mg twice daily
Answer: C
Rationale: This patient presents with an acute gout flare, characterized by the
sudden onset of severe pain, erythema, and swelling in a joint (classically the first
metatarsophalangeal joint), often with systemic symptoms like fever. The initial
treatment for an acute flare is colchicine or NSAIDs, with colchicine being a
standard choice. Allopurinol and febuxostat are urate-lowering therapies used for
chronic management and should not be started during an acute flare as they can
precipitate or worsen the flare. Probenecid is a uricosuric agent, also not for acute
flares.
4. A 55-year-old female with a history of chronic hepatitis C presents with fatigue
and right upper quadrant pain. Her liver function tests are elevated. An ultrasound
of the liver reveals a 3 cm hypoechoic mass. Serum alpha-fetoprotein (AFP) is 400
ng/mL. Which of the following is the most likely diagnosis?
A) Hepatic adenoma
B) Focal nodular hyperplasia
C) Hepatocellular carcinoma
D) Metastatic colon cancer
,E) Hepatic hemangioma
Answer: C
Rationale: In a patient with chronic liver disease (hepatitis C) and a liver mass, an
elevated AFP (>400 ng/mL) is highly suggestive of hepatocellular carcinoma
(HCC). Hepatic adenomas are more common in women on oral contraceptives and
do not typically present with such high AFP. Focal nodular hyperplasia is a benign
lesion with a central scar. Hemangiomas are benign vascular lesions.
5. A 32-year-old woman in her third trimester of pregnancy presents with a 2-day
history of a painful, vesicular rash on the left side of her face, along with blurred
vision in her left eye. On examination, you note vesicles on the tip of her nose
(Hutchinson's sign). Which of the following is the most appropriate antiviral agent
for this patient?
A) Acyclovir
B) Valacyclovir
C) Famciclovir
D) Ganciclovir
E) Foscarnet
Answer: A
Rationale: This patient has herpes zoster ophthalmicus, as indicated by the
vesicular rash and Hutchinson's sign (vesicles on the tip of the nose, which
indicates involvement of the nasociliary branch of the ophthalmic nerve and a high
risk of ocular involvement). The presence of blurred vision suggests ocular
involvement, which requires urgent treatment. Acyclovir is the antiviral of choice
in pregnancy due to its Category B safety profile and extensive experience. While
valacyclovir and famciclovir are also effective, they are Category B/C and
acyclovir is typically preferred in pregnancy.
6. A 60-year-old male with a 40-pack-year smoking history presents with a chronic
cough, hemoptysis, and unintentional weight loss of 10 pounds over the past 2
months. A chest CT shows a 4 cm mass in the right upper lobe with mediastinal
lymphadenopathy. A biopsy reveals small cell lung cancer. Which of the following
paraneoplastic syndromes is most commonly associated with this type of cancer?
A) Hypercalcemia
B) Hyponatremia
C) Cushing syndrome
D) Acanthosis nigricans
E) Clubbing and hypertrophic pulmonary osteoarthropathy
Answer: B
, Rationale: Small cell lung cancer (SCLC) is strongly associated with the syndrome
of inappropriate antidiuretic hormone (SIADH), leading to hyponatremia. While
SCLC can also cause Cushing syndrome (ectopic ACTH), SIADH is more
common. Hypercalcemia is most commonly associated with squamous cell
carcinoma of the lung. Acanthosis nigricans is associated with gastric cancer.
Hypertrophic pulmonary osteoarthropathy is associated with non-small cell lung
cancer.
7. A 28-year-old female presents with a chief complaint of "my heart is racing."
She reports intermittent episodes of palpitations, anxiety, and diaphoresis. During
one episode, her blood pressure was 180/100 mmHg and heart rate 120 bpm. She
also notes a history of severe headaches and episodic flushing. Her 24-hour urine
collection shows elevated levels of metanephrines and normetanephrines. Which of
the following is the most appropriate next step in management?
A) Initiate beta-blocker therapy immediately
B) Perform an abdominal CT scan to localize the tumor
C) Prescribe an alpha-blocker and then refer for surgical resection
D) Order a thyroid ultrasound to rule out medullary thyroid cancer
E) Start a low-sodium diet and a thiazide diuretic
Answer: C
Rationale: This patient presents with classic signs and symptoms of a
pheochromocytoma, a catecholamine-secreting tumor of the adrenal medulla. The
elevated metanephrines confirm the diagnosis. The most appropriate next step is to
initiate alpha-blockade (e.g., phenoxybenzamine) to control blood pressure and
prevent a hypertensive crisis. Beta-blockers should never be started before alpha-
blockers, as unopposed alpha stimulation can cause a severe hypertensive crisis.
After adequate alpha-blockade, surgical resection is the definitive treatment.
8. A 78-year-old male with a history of dementia is brought to the emergency
department from a nursing home with a fever and confusion. His temperature is
38.9°C (102.0°F). He is unable to provide a history. On examination, he has a
tender, distended abdomen. A urinalysis reveals cloudy urine with 50-100 WBCs
and positive nitrites. Which of the following is the most appropriate empiric
antibiotic choice?
A) Ciprofloxacin
B) Nitrofurantoin
C) Trimethoprim-sulfamethoxazole
D) Ampicillin
E) Doxycycline
Answer: A