In a patient with pituitary tumor and diabetes insipidus, which finding indicates seizure precautions are needed?

• A. Normal serum sodium
• B. High urine specific gravity
• C. Elevated serum sodium level
• D. Low urine output

Answer: (C)

Diabetes insipidus from a pituitary tumor causes free-water loss, which can lead to a hyperosmolar state. When serum sodium becomes elevated, it signals hypernatremia, and severe hypernatremia increases neuronal excitability, raising the risk of seizures. That is why an elevated serum sodium level indicates the need for seizure precautions. Normal serum sodium doesn’t show hypernatremia; high urine specific gravity would mean concentrated urine (not typical in DI, which usually has dilute urine); and low urine output would run contrary to the polyuric pattern of DI.