Adrenal Disorders USMLE Step 1 Practice Question
A 6-day-old female with ambiguous genitalia presents with vomiting and dehydration. Vital signs show BP 65/40 mmHg, HR 155/min, RR 32/min, and temperature 37.2°C. Laboratory studies reveal sodium 118 mEq/L, potassium 6.8 mEq/L, cortisol 2.1 mcg/dL (low), aldosterone 8 pg/mL (low), and elevated 17-hydroxyprogesterone at 8.5 ng/mL. Glucose is normal. She has not received any medications. Which of the following is the most likely diagnosis?
Answer choices
- AAndrogen insensitivity syndrome
- B5 alpha reductase deficiency
- C21 hydroxylase deficiencyCorrect answer
- D11 beta hydroxylase deficiency
- E17 alpha hydroxylase deficiency
- F3 beta hydroxysteroid dehydrogenase deficiency
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