Adrenal Disorders USMLE Step 1 Practice Question
A 16-year-old 46,XY phenotypic female presents with primary amenorrhea, absent breast development, and sparse pubic hair. Vital signs show BP 148/92 mmHg, HR 88/min, RR 16/min. Laboratory studies reveal serum potassium 2.8 mEq/L, cortisol 3 μg/dL (low), ACTH 156 pg/mL (elevated), and testosterone <10 ng/dL. Morning 17-hydroxyprogesterone is elevated at 8 ng/mL. She denies salt-wasting episodes. Which of the following is the most likely diagnosis?
Answer choices
- A11 beta hydroxylase deficiency
- BComplete androgen insensitivity syndrome
- C17 alpha hydroxylase deficiencyCorrect answer
- D5 alpha reductase deficiency
- E21 hydroxylase deficiency
- F3 beta hydroxysteroid dehydrogenase deficiency
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