Long-term effect of oral calcitriol single weekly pulse in CAPD and in HD.

This study was undertaken to evaluate the long-term effect of single weekly oral pulse calcitriol therapy (0.05 mcg/kg) in 16 uremic patients. Eight (5 female, 3 male; aged 51.6 +/- 8.5 years) were on continuous ambulatory peritoneal dialysis (CAPD) for 28.8 +/- 12.7 months with basal intact parathyroid hormone (iPTH) 247 +/- 60 pg/mL. Eight (6 female, 2 male; aged 53 +/- 17.9 years) were on hemodialysis (HD) for 76.3 +/- 55 months with basal iPTH 270.9 +/- 92. Calcium dialysate was 1.75 mmol/L in all patients and serum phosphorus was controlled with CaCO3 2-4 g/day. Ca and P were measured weekly; iPTH and alkaline phosphatase were measured monthly. After two months, iPTH decreased to 132.4 +/- 89 (p < 0.05 vs basal values) in the HD patients and to 158.2 +/- 61 (p < 0.05) in the CAPD group. After six months, iPTH decreased to 108.6 +/- 73.2 (p < 0.01) in the HD patients and to 126.5 +/- 48 (p < 0.01) in the CAPD patients. Two patients (1 HD and 1 CAPD) who were not compliant with phosphate binder therapy were dropped. To control hyperphosphatemia in 1 HD patient we reduced bolus to 0.03 mcg/kg. Two CAPD patients presented hypercalcemia and required calcium dialysate of 1.25 mmol/L. In conclusion, single weekly oral pulse of calcitriol appears to be effective in suppressing mild hyperparathyroidism both in CAPD and in HD patients, even though some variations in the protocols may be required.