Hypokalemia in children with leukemia in relapse.

Eight children with acute leukemia in relapse were hypokalemic during their hospital course. All had accompanying hypophosphatemia, and three had mild metabolic alkalosis. Potassium chloride supplementation in each case resulted in resolution of the electrolyte and acid-base disturbances. These findings were not present in patients with conditions newly diagnosed or those in remission. The pathogenesis of the electrolyte and acidbase disturbances was not evident and was not related to antibiotic or cytotoxic drug therapy, but may have been related to the patients' poor nutritional status. Seven of the eight patients died within six months of the hypokalemic episode. Hypokalemia may be a common accompaniment of terminal leukemia.