Long-term use of hemodiafiltration in two patients undergoing continuous ambulatory peritoneal dialysis

Two patients undergoing continuous ambulatory peritoneal dialysis (CAPD) for chronic renal failure developed restless leg syndrome associated with increased serum β 2 microglobulin and methylguanidine levels, suspected to be due to inadequate dialysis. Results of peritoneal function tests were normal in both patients, suggesting inadequate dialysis and increased production of uremic toxins by unknown mechanisms. Biochemical results and clinical symptoms were improved by concurrent hemodiafiltration. The patients used CAPD combined with biweekly hemodiafiltration with good clinical results over the 6-year period from 1989 to 1995. Periodic hemodiafiltration may enable patients who must otherwise discontinue CAPD treatment due to insufficient dialysis to continue long-term CAPD without affecting rehabilitation.