How do you evaluate the etiology of hyponatremia in a patient with ESRD and baseline oliguria/anuria?

In patients with ESRD and baseline oliguria or anuria, hyponatremia has to be approached differently because many of the usual diagnostic and monitoring tools (urine sodium, urine osmolality, urine output) are either unavailable or misleading. The key shift is to think in terms of total body water v...

Thinking of what happens between dialysis treatments is very helpful.

Suggest checking for paraproteinemia.