Effect of oral 1,25 dihydroxycholecalciferol on calcium and phosphate malabsorption in primary biliary cirrhosis.

Changes in calcium and phosphate absorption in response to treatment with small doses of oral 1,25 (OH)2D3 were studied in 10 patients with primary biliary cirrhosis by means of a combined radio-isotope technique. There was a marked improvement in the fractional rates of absorption of calcium (P less than 0.01) and phosphate (0.05 P less than 0.1) after treatment. This implies than there is no end organ unresponsiveness to the action of active Vitamin D metabolites at the intestinal level in primary biliary cirrhosis.