Interaction between serum calcium concentration and glucose tolerance in normal and azotaemic patients

Summary The effect of calcium infusion on the intravenous glucose tolerance was tested in hypocalcaemic patients suffering from renal insufficiency. It was shown that the delayed glucose disappearance rate in uraemics could be improved (p < 0.005) by the infusion of calcium gluconolactobionate despite the fact that the serum concentrations of potassium, urea nitrogen, and the blood pH were not altered. The basal insulin concentration was significantly depressed by the calcium infusion (p < 0.02). The serum calcium concentration was significantly correlated to the glucose assimilation coefficient in the uraemic patients (p < 0.01). — 3 hypocalcaemic patients without renal failure had a normal glucose tolerance and a normalization of the serum calcium concentration had no discernable effect. — A slight but significant decrease of the serum calcium concentration (p < 0.01) by EDTA-Na₂ in normocalcaemic patients did not change the intravenous glucose tolerance. — It is concluded that hypocalcaemia may be one of the causes for the abnormal glucose tolerance in chronic renal failure.