Low molecular weight proteins as urinary markers of aminoglycoside nephrotoxicity in man.

The proteinuria of fifteen patients treated with just aminoglycoside or aminoglycoside and either penicillin or cephalosporin was studied. The proteinuria was analysed by means of immunoelectrophoresis, acetate cellulose electrophoresis, thin-layer polyacrylamide gel electrophoresis and sodium dodecylsulphate acrylamide gel electrophoresis. We observed a urinary excretion of free immunoglobulin light chains and an increased urinary excretion of lysozyme in all cases. The increase in urinary excretion of beta-2-microglobulin and retinol-binding-protein appeared only in patients treated with aminoglycoside and cephalosporin. These disturbances disappeared a few days after the treatment was discontinued.