Histological renal osteodystrophy, and 25 hydroxycholecalciferol and aluminum levels in patients on continuous ambulatory peritoneal dialysis

Renal osteodystrophy, which influences the quality of life and contributes to the morbidity of patients with endstage renal failure [1], has been reported to deteriorate in patients treated with continuous ambulatory peritoneal dialysis (CAPD) [2]. However, better control of serum calcium and phosphate in these patients [3] has provided preliminary data that show improvement in histological grading of osteitis fibrosa (OF) in our patients treated with CAPD [41.Another form of bone disease, the osteomalacic dialysis osteodystrophy (OM), which may be associated with dialysis encephalopathy, is thought in some instances to be due to aluminum toxicity [5] from untreated or softened water used in hemodialysis in areas where the aluminum content of water supplies is high [6]. In patients undergoing CAPD any exposure to aluminum is likely to stem from the use of aluminum-containing phosphate binders (ACPB) since the process of preparation of peritoneal dialysis fluid reduces most of the trace metals.In our unit, since the inception of the CAPD program in January 1979, 72 patients have been treated by this method in the first 2 years. In this report we present data on the improvement of histological renal osteodystrophy in CAPD patients and relate this to serum concentrations of calcium, phosphate, 25 hydroxycholecalciferol [25-(0H)CC] and immunoreactive parathormone (PTH). In addition, sequential serum aluminum concentrations are reported. These levels have been related to concentrations of aluminum in the peritoneal dialysis (PD) fluid and to the use of ACPB. One patient with aluminum toxicity prior to starting CAPD was studied to evaluate the chelating effect of disferrioxamine (DFO) on aluminum and its subsequent removal in the PD fluid