Transient glomerular proteinuria, enzymuria, and nephrotoxic reaction induced by radiocontrast media

Contrast nephropathy is a recognized complication of arteriographic procedures; usually, it consists of a mild deterioration of renal function. In an attempt to understand better the mechanisms involved, we conducted a prospective study before and after arteriography that monitored the urinary elimination of high- and low-molecular weight proteins, the urinary activity of tubular enzymes, and renal clearances of 27 patients. We detected a noticeable and transient nonselective proteinuria of glomerular origin together with moderate signs of tubular damage and a stable renal function. We did not identify any risk factor. Contrast media may alter the disposition of charges along the glomerular filtering membrane in a way that promotes proteinuria; consequently, the massive flow of proteins may injure the tubular cells.