Vitamin a toxicity and hypercalcaemia in chronic renal failure

Abstract

Serum vitamin A concentrations were measured in 38 patients undergoing haemodialysis, 24 of whom weretaking multivitamin preparations containing vitamin A. Vitamin A concentrations were significantly higher in patients undergoing haemodialysis than in 28 normal controls (p 0.001). Patients taking vitamin A supplements had significantly higher vitamin A concentrations than those not taking them (p 0 05), and hypercalcaemic patients had higher concentrations than normocalcaemic patients (p 0 005). Withdrawal of vitamin A supplements in seven patients caused significant falls in serum vitamin A concentrations and plasma calcium concentrations (p0 01 at two and three months in both cases) and in plasma alkaline phosphatase concentrations (p 0 01 at two months). Vitamin A toxicity can contribute to hypercalcaemia in patients undergoing haemodialysis, probably by an osteolytic effect. Multivitamin preparations containing vitamin A should therefore be prescribed with caution in these patients. © 1981, British Medical Journal Publishing Group. All rights reserved.