High doses of intravenous calcitriol in the treatment of severe secondary hyperparathyroidism.

BACKGROUND

In hemodialysis (HD) patients, secondary hyperparathyroidism (HPTH) is a severe common disease. Calcitriol administration has been demonstrated as an effective therapy. In this prospective study, our aim was to determine the necessary calcitriol dose required to control severe HPTH preventing hypercalcemia or hyperphosphatemia and avoiding parathyroidectomy.

METHODS

Eighteen dialysis patients suffering from severe HPTH during a 12-month period received intravenous (i.v.) calcitriol pulse doses (2-8 mcg/3x/week). Multislice helical computed tomography (CT) cardiac imaging was performed to measure coronary artery calcifications.

RESULTS

Fourteen patients showed an improvement (parathyroid hormone (PTH) level < 400 pcg/mL), one patient an incomplete reduction, and three patients starting from PTH levels between 1100 and 2386 pcg/mL did not appear to benefit from the therapy. After a 6-month therapy in 15/18 patients PTH levels were significantly lower (p<0.05). In a large portion of the group, as well as in the control group, coronary calcification values were high when compared to the normal range.

CONCLUSIONS

According to our data, we concluded that severe HPTH could be treated successfully by i.v. calcitriol pulse doses reaching high doses (up to 8 mcg/3x/week) and for a prolonged period of time (6 months). In such cases, close monitoring is necessary to prevent hyperphosphatemia and hypercalcemia episodes.