Influence of hepatitis C virus (HCV) viraemia upon serum aminotransferase activity in chronic dialysis patients.

BACKGROUND

There are many reports concerning HCV in dialysis patients and most of them conclude that the clinical and biochemical features of hepatitis C are often silent in chronic dialysis patients. Elevated levels of serum alanine aminotransferase activity are a sensitive measure of hepatocellular injury, but so far the relationship between anti-HCV and ALT among chronic dialysis patients has been considered imperfect. To our knowledge, however, such an issue has not been adequately addressed.

METHODS

Demographic, biochemical, and virological data from 506 patients undergoing chronic dialysis treatment in four dialysis units in Lombardy, northern Italy were collected in order to assess the influence of virological and host factors on serum aminotransferase values.

RESULTS

Analysis of covariance showed that positivity for anti-HCV antibody was significantly associated with raised serum AST (P = 0.0001) and ALT (P = 0.0001) levels in the dialysis patients of the whole study group. Logistic regression analysis performed in the subset of patients tested for HCV viraemia and genotype showed that detectable HCV RNA in serum is a strong predictor of raised AST (P = 0.0001) and ALT (P = 0.000001) values. Gender showed an independent weak influence on AST levels (P = 0.055), serum levels of ferritin were significantly (P = 0.042) associated with AST values, the coexistence of HBsAg infection and positivity for anti-HCV antibody was independently associated with raised ALT levels (P = 0.016). The other factors (including positivity for anti-HCV) showed no independent effect on serum aminotransferase levels when they were matched with HCV viraemia in our multivariate analysis. HCV RNA positive patients showed serum AST (P < 0.008) and ALT levels (P < 0.0001) higher than HCV RNA negative patients. There was no relationship between HCV genotypes and liver enzymes.

CONCLUSIONS

Our data show that detectable HCV RNA in serum is a strong independent predictor of raised aminotransferase values in chronic dialysis patients; the relationship between serum aminotransferase values and anti-HCV antibody was exclusively related to the association between raised aminotransferase values and HCV viraemia; HCV RNA positive patients show higher hepatic enzyme levels than dialysis patients with no detectable HCV RNA; no association between HCV genotype and serum aminotransferase activity was apparent.