Clinical and Laboratory Findings in Patients with Medullary Sponge Kidney

Structural abnormalities of the urinary tract are usually thought to predispose to renal stone formation. Medullary sponge kidney is probably a congenital abnormality. Because of such structural abnormalities, a higher incidence of tubular dysfunction may be anticipated. However, a broad investigation of renal tubular function has not been performed in larger series. The renal acidification capacity has only been investigated in a few patients and found to be defective in some of these1. In some cases the diagnosis of renal tubular acidosis (RTA) might have been overlooked2,3. It seems important to diagnose the acidification defect since it seems to be associated with a more severe stone disease4.