Diabetes Mellitus USMLE Step 1 Practice Question
A 27-year-old man develops intense thirst and polyuria 1 week after a traumatic brain injury. Serum sodium is 151 mEq/L, serum osmolality is elevated, and urine osmolality is low. During a water deprivation test, urine remains dilute but becomes concentrated after desmopressin administration. Which of the following is the most likely diagnosis?
Answer choices
- ASIADH
- BCentral diabetes insipidusCorrect answer
- CNephrogenic diabetes insipidus
- DPrimary polydipsia
- ECerebral salt wasting
- FAcute tubular necrosis
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