Distribution of hepatitis C virus infection in liver biopsies from children and adults with chronic hepatitis C

Chronic hepatitis C in children is characterized by milderforms of liver da mage than those found in adults. Such a difference has been attributed to a low viral load in children that may lead to poor recognition of infected c ells by the immune system. One approach that could be used to confirm this hypothesis may be to examine the number of infected hepatocytes in liver bi opsies. Paraffin embedded liver biopsies from 21 children and 15 adults wit h chronic hepatitis C virus (HCV) infection (with a similar duration of the infection) were hybridized in situ and the percentage of infected hepatocy tes was correlated with the histological activity index, alanine aminotrans ferase levels and HCV viraemia levels. Histological activity index and HCV viraemia levels were statistically higher (P<0.05 and P<0.01 respectively) in adults than in children, and the percentage of infected hepatocytes was higher in adults (11.0 +/- 19.7%) than in children (4.6 +/- 3.6%), although it did not reach statistical significance. Also, the percentage of infecte d hepatocytes correlated with HCV-RNA concentration in serum in both childr en (r=0.683, P=0.001) and adults (r=0.768, P=0.001). The results show that liver damage in children with chronic hepatitis C is not related to the ext ent of infection in the liver. This findings support the hypothesis of that liver injury in chronic HCV infection is mediated by the host immune respo nse. J. Med. Virol. 64: 1-5, 2001. (C) 2001 Wiley-Liss, Inc.