system
Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
A 39-year-old man comes to the physician because of frequent urination for the past 2 months. He has been urinating 10–12 times during the day and 3–4 times during the night. He says he is drinking a lot of water to compensate for any dehydration. He has no history of serious illness and takes no medications. Vital signs are within normal limits. Physical examination shows no abnormalities. He is concerned he may have diabetes mellitus like his parents. Laboratory studies show:
Hemoglobin 14.3 g/dL
Serum
Na+ 149 mEq/L
K+ 3.9 mEq/L
Cl- 102 mEq/L
Glucose 90 mg/dL
Osmolality 306 mOsmol/kg H2O
Urine
Osmolality 210 mOsmol/kg H2O
A water deprivation test is conducted. After 2 hours of fluid restriction, his plasma osmolality is 315 mOsmol/kg H2O and his urine osmolality is 210 mOsmol/kg H2O. One hour after an ADH analog injection, his plasma osmolality is 276 mOsmol/kg H2O and his urine osmolality is 425 mOsmol/kg H2O. Which of the following is the most appropriate next step in management?"
assistant
Desmopressin therapy