Renal failure in cirrhosis has multiple etiologies and numerous aggravating factors with evidence of worsening of prognosis. Our study was performed on 130 cirrhotic patients hospitalized in HDF between January 1st, 1994, and December 31st, 1999. We have evaluated the causes of renal failure and the relation of different aggravating factors with the onset of renal failure. Causes of renal failure included drug-induced renal failure, organic nephropathy, pre-renal azotemia, acute tubular necrosis and hepato-renal syndrome. Among the aggravating factors, lactulose was found to alter renal function (p = 0.0175). We studied the survival with respect to the serum creatinine levels and to the severity of liver disease. Three-year survival was respectively 59% and 42% in case of Child A and Child B patients with creatinine lower than 90 micromol/L. No three-year survivors were noted in these subsets of patients when creatinine level was higher than 90 micromol/L (p = 0.0247 and p = 0.0121 respectively). No difference in survival was noted in Child C cirrhosis. The occurrence of renal failure is a factor of bad prognosis in cirrhotic patients irrespective of Child's classification. In patients with Child A and Child B cirrhosis, a serum creatinine level higher than 90 micromol/L is a bad prognostic factor with a significantly decreased survival rate. This factor does not affect survival in Child C cirrhosis because of mortality related to cirrhosis complications.