Serum Parathyroid Hormone Suppression by Intravenous 1,25-Dihydroxy vitamin D3 in Patients on Maintenance Haemodialysis

Abstract

Secondary hyperparathyroidism in patients with end-stage renal disease is characterised by elevated circulating levels of parathyroid hormone, due to inadequate synthesis of calcitriol, the active metabolite of vitamin D. Recent studies suggest that administration of calctriol may directly suppress parathyroid (PTH) secretion independent of changes in serum calcium. We have studied the effect of intravenous calcitriol administration on the PTH level in 14 patients on maintenance haemodialysis with serum PTH levels above 2,000 pmol/l over a 16-week period. There was a significant reduction in the PTH level (65%) and a rise of serum calcium to the normal range. There was a significant reduction in serum PTH levels before the serum calcium concentrations increased, suggesting that calcitriol directly inhibits PTH release. In conclusion, intravenous treatment with calcitriol is of clinical importance, because it suppresses hypersecretion of PTH in uraemic patients, with minimal side effects.

Long-Term Intravenous Calcitriol in Secondary Hyperparathyroidism: The Role of Technetium-99m-Mibi Scintigraphy in Predicting the Response to Treatment

“…calcitriol in reducing the PTH in dialysis patients with secondary hyperparathyroidism (9), which was also demonstrated by an earlier report by Slatopolsky (10) and confirmed further by other subsequent studies (11)(12)(13)(14)(15). However, the duration of follow-up in these studies was short (weeks to few months).…”