[Elimination of aluminum via continuous ambulatory peritoneal dialysis]

Aluminum concentrations in the dialysate and serum of 14 patients on CAPD were measured every six months. Additionally, in ten of the patients Al elimination was measured after a bolus ingestion of 1800 mg aluminium-chloride-hydroxide-complex. There was no significant difference between serum Al concentrations initially (47.3 +/- 8.2 micrograms/l), at six months (55.4 +/- 9.5 micrograms/l), and after 12 months (44.3 +/- 10.1 micrograms/l) although the Al concentration in the dialysate had been decreased from 16.6 +/- 2.3 micrograms/l to 1.5 +/- 0.2 in the last six months. The Al concentrations in the effluent dialysate were 14.5 +/- 1.3 micrograms/l initially, 15.6 +/- 1.2 micrograms/l after six months and 11.9 +/- 2.6 micrograms/l after 12 months. During kinetic studies a constant rise of serum Al concentration was found until the fifth hour, from 29.9 +/- 2.5 to 42.5 +/- 4.0, and a decline after 24 hours to 32.4 +/- 3.0 micrograms/l. The quantity of Al eliminated was 41.1 +/- 8.7 micrograms/24 h, equivalent to 1.2% of the ingested dose. In patients with residual renal function, renal Al clearance was almost double the peritoneal one. These results indicate that Al elimination by CAPD is not efficient and ingestion of Al-containing phosphate binders can result in Al accumulation.