In our study we have compared efficacy of both metabolites of vitamin D3 administered in high doses in a pulsatile manner in the treatment of hyperparathyroidism secondary to uraemia. 27 chronically dialysed patients aged 19-61 were divided into two groups: Group 1 (13 subjects) in which patients were receiving 1,25(OH)D3, and Group 2 (14 subjects) treated with 1 alpha-OH-D3,. Both drugs were given orally, 3 times a week, during dialysis in a dose dependent upon serum calcium concentration (up to 5 micrograms at the highest). Apart from that our patients were given calcium carbonate and some of them also aluminium hydroxide. Calcium concentration in a dialysate was lowered to 1.40-1.45 mmol/l. Our study has shown similar efficacy of both Vitamin D3, metabolites: during 8 months of treatment with similar doses we have observed in both groups significant decrease of serum parathormone (PTH), hydroxyproline and alkaline phosphatase concentrations as well as increase in serum calcium concentration. Serum 1,25(OH)2,D3, measured before and after treatment have shown twice as high increase in its concentration (compared to the levels at the start point) in the group of patients treated with alphacalcidiol which proves it to be more effective in maintaining constant physiological levels of 1,25 (OH)2,D3, in serum.

Keywords: Calcitriol, alfacalcidiol, end stage renal failure, secondary hyperparathyroidism