1.25(OH)2 cholecalciferol pulse therapy and the effects of different dialysis membranes on serum PTH levels of haemodialysis patients

Either oral, intravenous or subcutaneous 1.25(OH)2 cholecalciferol is used in the therapy of hyperparathyroidism, which is a serious complication in patients on haemodialysis. We studied a total of 30 patients (10 women and 20 men) and divided them into two groups depending on the different types of dialysis membranes used. In the polysulfone group, mean age was 43.7 +/- 0.97 years and the average dialysis period lasted 29.9 +/- 1.23 months. For the 15 cases in which we used cuprophane membrane the mean age was 40.2 +/- 1.31 years and the average dialysis period lasted 16.2 +/- 0.86 months. The calcium level of the dialysate in both groups was 1.5 mmol/l. According to the study protocol, the determined oral calcitriol dose was 0.07 mg/kg and it was administered intermittently. After one month on high dose calcitriol therapy, treatment was continued with a maintenance dose of 0.03 mg/kg for a further six months. As a phosphate binding agent, daily 3 g calcium carbonate was administered. Before starting this treatment protocol, patients went on a 1 mg/day calcitriol therapy, although the mean PTH level was 424.63 pg/ml and the mean serum alkaline phosphatase level was 290.2 U/l. During the pretreatment period, levels of PTH, alkaline phosphatase, ionized calcium, and total calcium remained significantly within normal limits as a result of the new therapy protocol applied. PTH and phosphorus clearance rates were compared in the patient groups in which different dialysis membranes had been used. PTH and phosphorus clearances were 15.2 +/- 3 ml/min and 239.1 +/- 19.2 ml/min, respectively, in the polysulfone membrane group, and 1.1 +/- 0.3 ml/min and 112.8 +/- 9.88 ml/min, respectively, in the cuprophane membrane group (p < 0.05).