Effects of oral calcium carbonate on control of serum phosphorus and changes in plasma aluminum levels after discontinuation of aluminum-containing gels in children receiving dialysis.

Orally administered calcium carbonate was evaluated as a phosphate binding agent in 15 children, ages 0.6 to 17.2 years, receiving maintenance dialysis. Changes in plasma aluminum concentration were assessed after discontinuation of treatment with aluminum-containing gels. The mean daily dose of calcium carbonate was 5.1 +/- 2.5 gm (384 +/- 315 mg/kg/day), and correlated inversely with body weight (r = 0.72, P less than 0.01) and age (r = 0.71, P less than 0.01). Mean serum calcium, phosphorus, and bicarbonate values were unchanged throughout the study. Plasma aluminum concentration fell from 90 +/- 51 to 34 +/- 22 micrograms/L (P less than 0.005). Dietary phosphorus intakes were 44 +/- 21 and 42 +/- 19 mg/kg/day during the control period and at the end of the study, respectively. Transitory hypercalcemia was the only side effect in 92% of the patients. In none of the patients did uncontrolled hyperphosphatemia, metabolic alkalosis, diarrhea, or symptoms or signs of hypercalcemia develop. Our data indicate that calcium carbonate is an effective phosphate binding agent in children receiving dialysis, and should be used in lieu of aluminum-containing gels in young children with renal failure.