Diabetes Mellitus USMLE Step 1 Practice Question
A newborn girl with ambiguous genitalia presents on day 8 of life with vomiting and dehydration. Vital signs show BP 55/32 mmHg, HR 158/min, RR 32/min, temperature 36.8°C. Laboratory studies reveal sodium 118 mEq/L, potassium 6.8 mEq/L, and elevated 17-hydroxyprogesterone. She has no fever or respiratory distress. Parents report no medications. Which of the following is the most likely diagnosis?
Answer choices
- AAndrogen insensitivity syndrome
- BTurner syndrome
- C11-beta hydroxylase deficiency
- D21-hydroxylase deficiencyCorrect answer
- E17-alpha hydroxylase deficiency
- FCongenital adrenal hypoplasia due to DAX1 mutation
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