Vitamin D therapy in CAPD: what is its role?

Recognition of the harmful effects of aluminum, its replacement by calcium salts, the introduction of reduced calcium dialysis fluid, and the availability of sensitive and specific assays for intact 1-84PTH have resulted in changes in the monitoring and management of renal osteodystrophy in continuous ambulatory peritoneal dialysis (CAPD). In addition, better understanding of the calcitriol/parathyroid axis enables a more structured approach to the treatment of patients with established hyperparathyroid bone disease. Wherever possible, CAPD patients should undergo tetracycline labeled bone biopsy at the time of starting dialysis in order to establish the exact bone histology. Thereafter management can be rationally decided on the basis of regular monitoring of serum intact parathyroid hormone (iPTH). Routine prophylactic use of calcitriol is unnecessary, but when iPTH levels rise, despite strict control of calcium and phosphate levels, oral pulse therapy is an effective and inexpensive method of controlling hyperparathyroidism. However, long-term histological studies of its benefit are awaited.