Prolonged volume depletion imitating end-stage renal failure

Four patients with chronic renal insufficiency were erroneously diagnosed as reaching the "end stage" of their disease. All of them had had insidious salt and water depletion prolonged over a period of 5 to 8 weeks. The correct diagnosis was missed because the signs and symptoms of slowly developing volume depletion were indistinguishable from the clinical picture of terminal uremia. Correction of the salt and water depletion was followed by marked clinical improvement and return of renal function to baseline values. Postural hypotension and hyponatremia are important clues for the diagnosis of insidiously developing mild or moderate volume depletion super-imposed on chronic renal insufficiency.