Zinc metabolism in patients with chronic renal failure during treatment with 1.25-dihydroxycholecalciferol: a controlled therapeutic trial.

Serum concentrations and urinary excretion rates of zinc, calcium and magnesium were measured in 17 patients with chronic renal failure before and after treatment with 1.25(OH)2D3 or vitamin D3. Initially the patients showed hypozincemia (P less than 0.001), hypocalcemia (P less than 0.01) and hypermagnesemia (P less than 0.01). The distribution of zinc between albumin and alpha 2-macroglobulin was calculated. The reduction in serum zinc was due to a fall in the albumin bound fraction, which could not be explained by a reduction in the serum albumin concentration. During treatment with 1.25(OH)2D3 no significant changes in serum and urinary levels of zinc and magnesium were observed, while the serum concentrations and urinary excretion rates of calcium increased. It is concluded that 1.25(OH)2D3 and vitamin D3 are of minor importance in the intestinal absorption of zinc and magnesium.