SMLE Internal Medicine 4 — Questions and Answers
Question 1: A 58-year-old patient with long-standing uncontrolled diabetes presents with decreased sensation in a glove-and-stocking distribution. Nerve conduction studies show axonal neuropathy. What type of neuropathy is this?
- Mononeuropathy
- Distal symmetric polyneuropathy (Correct answer)
- Autonomic neuropathy
- Cranial neuropathy
Correct answer: Distal symmetric polyneuropathy
Distal symmetric polyneuropathy is the most common form of diabetic neuropathy, presenting with sensory loss in a glove-and-stocking pattern. It is length-dependent, affecting the longest nerves first.
Question 2: A 42-year-old woman with a BMI of 38 presents with right upper quadrant pain after a fatty meal, fever, and a positive Murphy sign. What is the most appropriate initial imaging?
- CT abdomen with contrast
- Abdominal X-ray
- Abdominal ultrasound (Correct answer)
- MRCP
Correct answer: Abdominal ultrasound
Abdominal ultrasound is the first-line imaging for suspected acute cholecystitis. It can demonstrate gallstones, gallbladder wall thickening, pericholecystic fluid, and a sonographic Murphy sign with high sensitivity and specificity.
Question 3: Which of the following is the most common electrolyte abnormality in a patient with diabetic ketoacidosis (DKA)?
- Hypercalcaemia
- Hypernatraemia
- Total body potassium depletion (Correct answer)
- Hypermagnesaemia
Correct answer: Total body potassium depletion
Despite sometimes presenting with normal or elevated serum potassium (due to transcellular shift from acidosis and insulin deficiency), patients with DKA have significant total body potassium depletion from osmotic diuresis and vomiting.
Question 4: A 25-year-old male presents with recurrent oral ulcers, genital ulcers, and anterior uveitis. What is the most likely diagnosis?
- Crohn disease
- Behçet disease (Correct answer)
- Herpes simplex
- Reactive arthritis
Correct answer: Behçet disease
Behçet disease presents with the classic triad of recurrent oral ulcers, genital ulcers, and uveitis. It is more common in countries along the ancient Silk Road, including Saudi Arabia and the Middle East.
Question 5: A patient with newly diagnosed hypertension has a potassium of 2.8 mmol/L and metabolic alkalosis. The aldosterone-to-renin ratio is elevated. What is the most likely diagnosis?
- Cushing syndrome
- Renal tubular acidosis
- Primary hyperaldosteronism (Conn syndrome) (Correct answer)
- Liddle syndrome
Correct answer: Primary hyperaldosteronism (Conn syndrome)
Primary hyperaldosteronism (Conn syndrome) presents with hypertension, hypokalaemia, metabolic alkalosis, and an elevated aldosterone-to-renin ratio. It is the most common cause of secondary hypertension due to adrenal pathology.
Question 6: In a patient with suspected acute coronary syndrome, which cardiac biomarker is the most sensitive and specific for myocardial injury?
- Creatine kinase-MB (CK-MB)
- High-sensitivity troponin (Correct answer)
- Lactate dehydrogenase (LDH)
- Myoglobin
Correct answer: High-sensitivity troponin
High-sensitivity troponin (either I or T) is the most sensitive and specific biomarker for myocardial injury and is the preferred test for diagnosing acute myocardial infarction per current guidelines.
SMLE Internal Medicine 4
A 58-year-old patient with long-standing uncontrolled diabetes presents with decreased sensation in a glove-and-stocking distribution.
Nerve conduction studies show axonal neuropathy.
What type of neuropathy is this?