Diabetes Mellitus USMLE Step 1 Practice Question
A 6-year-old boy presents with early pubic hair development and accelerated linear growth. Vital signs show BP 148/92 mmHg, HR 88/min, RR 18/min, temperature 37°C. Laboratory studies reveal low cortisol (3 μg/dL), suppressed plasma renin activity, and markedly elevated DHEA-S (580 μg/dL). Serum glucose is normal. Abdominal imaging shows no masses. Which enzyme deficiency best explains these findings?
Answer choices
- A21 hydroxylase
- B17 alpha hydroxylase
- C5 alpha reductase
- D11 beta hydroxylaseCorrect answer
- EAldosterone synthase
- F3 beta hydroxysteroid dehydrogenase
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