Is 1,25-dihydroxy-cholecalciferol harmful to renal function in patients with chronic renal failure?

Seventeen undialysed adult patients with chronic renal failure took part in a controlled study of the effects of 1,25(OH)2D3 and D3. After a 6-month observation period the patients were allocated at random to two groups for 6 months of treatment with either 1,25(OH)2D3 (mean dose 0.5 microgram daily) or D3 (dose 100 microgram daily). Treatment was then discontinued and the patients were studied for a further 6 months. Serum iPTH was decreased in both groups but most markedly in the 1,25(OH)2D3 group in which the iPTH values became normal. Serum creatinine increased during treatment in both groups. In the group receiving 1,25(OH)2D3 this was coupled to an increase in serum calcium within the normal range. Our data demonstrate that 1,25(OH)2D3 treatment in patients with chronic renal failure leads to a further reduction in renal function, which may be partially reversible. Physicians should therefore be reluctant to give vitamin D analogues to patients with chronic renal failure unless they have severe symptomatic renal osteodystrophy.