Idiopathic hypercalciuria: the contribution of Dr. Jacob Lemann, Jr.

The original contributions of Jacob Lemann to mineral metabolism, especially calcium metabolism and idopathic hypercalciuria, are reviewed. One group of studies concern acid base balance and calcium loss, showing that acid loads increase calcium loss in the urine. Another group of studies concern the calciuria of glucose or carbohydrate ingestion, with the observation that stone patients, who as a population are enriched with hypercalciuria, respond with more exaggerated calciuria to glucose loads than do normal people. Yet another body of work shows that normal men, when given noncalcemic loads of calcitriol, exhibit two essential features of idiopathic hypercalciuria--hyperabsorptive hypercalciuria and bone mineral loss on a low-calcium diet. The final group of studies presented worked on the problem of thiazide hypocalciuric action, and where the calcium goes that does not appear in the urine, as well as the effects of potassium bicarbonate and sodium loads on mineral balance and acid base status.