Question

A 70-year-old man with chronic heart failure and atrial fibrillation presents with confusion. Serum sodium is 120 mEq/L, serum osmolality is low, and urine sodium is high. He is euvolemic on exam. What is the most likely diagnosis?

Accepted Answer

Syndrome of inappropriate antidiuretic hormone secretion

Answer

Hypovolemic hyponatremia

Answer

Hypervolemic hyponatremia

Answer

Pseudohyponatremia

Answer

Primary polydipsia

Practice question

A 70-year-old man with chronic heart failure and atrial fibrillation presents with confusion. Serum sodium is 120 mEq/L, serum osmolality is low, and urine sodium is high. He is euvolemic on exam. What is the most likely diagnosis?