A 57-year-old man is referred for assessment of his low serum sodium of 125 mEq/L. On examination, he has pitting edema and elevated neck veins. His urine sodium is 10 mEq/L and urine osmolality 350 mOsm/kg.For the above patient with hyponatremia, select the most likely diagnosis.
High-Yield Explanation
Hyponatremia associated with nephrotic syndrome, cirrhosis, or CHF is characterized by edema. It is believed that the hyponatremia is caused by a decrease in "effective" circulating volume secondary to decreased cardiac output or sequestration of fluid.