ABSTRACT
The intestinal absorption and the urinary excretion of calcium were compared in two groups of diabetic patients during periods of satisfactory and poor control. In a first group of ten patients, periods of isolated high glycosuria were obtained by giving an oral glucose load. The second group consisted of ten patients with a severe endogenous insulin deficiency. The subjects of this latter group were investigated before and after a few days of insulin therapy. In group I, the oral glucose load induced a significant increase in the intestinal calcium absorption and had a tendency to lower the urinary calcium excretion. Furthermore, an inverse relationship was found between the changes in the intestinal calcium absorption and the variations of the urinary calcium excretion. In group II, both intestinal absorption and urinary excretion of calcium fell significantly after recovery of satisfactory metabolic control by insulin therapy. From the results as obtained in group I one can conclude that glucose enhances the calcium transfer from the luminal to the serosal pole of both intestinal and renal tubular cells. During severe ketosis as observed in group II, calcium metabolism is considerably accelerated and the increase in the intestinal calcium absorption rate may be interpreted as compensatory mechanism for the high urinary loss of calcium.
