Profound hypophosphatemia in the course of acute renal failure

Four of 19 patients with acute renal failure (ARF) requiring dialytic therapy were hypophosphatemic (serum phosphate, 0.8 +/- 0.8 mg/dL) during their illness. The hypophosphatemia could not be attributed to differences in the etiology of renal failure, frequency of dialysis, or residual renal function. No hypophosphatemic patient received phosphate-binding antacids. The hypophosphatemia was related to carbohydrate (CHO) providing a large percentage (greater than 79%) of total calories for a prolonged period. This complication was likely caused by tissue anabolism as well as by CHO-stimulated, insulin-induced intracellular shifts of phosphate. The greater use of parenteral fat as a caloric source and more aggressive phosphate supplementation despite the presence of ARF may help prevent this complication.