Adrenal Disorders USMLE Step 1 Practice Question
A 7-year-old girl presents with pubic hair development and accelerated linear growth over 6 months. Vital signs show BP 132/88 mmHg, HR 92/min, RR 18/min, temp 37°C, SpO2 98%. She denies salt cravings. Laboratory studies reveal cortisol 3 µg/dL (low), plasma renin activity 0.3 ng/mL/hr (suppressed), and 17-hydroxyprogesterone 8 ng/mL (elevated). ACTH is appropriately elevated. Which enzyme deficiency best explains these findings?
Answer choices
- A11 beta hydroxylaseCorrect answer
- B17 alpha hydroxylase
- C21 hydroxylase
- D17 beta hydroxysteroid dehydrogenase
- EAromatase
- F3 beta hydroxysteroid dehydrogenase
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