Diabetes Mellitus USMLE Step 1 Practice Question
A 17-year-old 46,XY phenotypic female with primary amenorrhea presents with BP 152/94 mmHg, HR 88, RR 16, temp 37°C. Labs show cortisol 3 mcg/dL (low), testosterone 18 ng/dL (low), estradiol <5 pg/mL (low), and elevated deoxycorticosterone at 8 ng/mL. Serum potassium is normal at 4.2 mEq/L. She denies salt craving or hyperpigmentation. Which enzyme deficiency best explains these findings?
Answer choices
- A21 hydroxylase
- B11 beta hydroxylase
- C17 alpha hydroxylaseCorrect answer
- DAromatase
- ETyrosine hydroxylase
- F3 beta hydroxysteroid dehydrogenase
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