Spectrum of renal tubular damage in renal failure secondary to cirrhosis and fulminant hepatic failure.

Measurements of urinary lysozyme were used to evaluate renal tubular integrity in 34 patients with cirrhosis or fulminant hepatic failure who had developed renal impairment. In 18 of the patients the lysozyme values were normal but in the remaining 16 were increased, supporting previous concepts that renal failure complicating hepatocellular disease may occur both without and with tubular necrosis. The lysozyme values were inversely related to the creatinine clearance, suggesting that the development of tubular necrosis may be determined by the level of renal perfusion. The validity of simpler laboratory tests often used to assess renal tubular integrity--namely, the urine sodium concentration, the urine:plasma osmolality ratio, and casts in the urine sediment--was evaluated by comparison with the lysozyme measurements. The urine sodium concentration was of most value and the findings in the sediment were of no value at all.