Hepatitis C virus genotypes in chronic hepatitis C of children

SUMMARY. Several hepatitis C virus (HCV) genotypes have been recently identified and genotype 1b has been correlated with severe liver disease and a poor response to interferon therapy. HCV infection in children is an interesting model for evaluation of the relationship between HCV genotypes and liver disease, because of its relatively short duration and the infrequent association with confounding cofactors. We have investigated HCV genotypes, using a dot-blot hybridization assay with genotype-specific probes, in 36 Italian children with chronic hepatitis C who were otherwise well and had no other underlying disease. Only four patients were symptomatic; liver histology, obtained in 3 3 patients, showed minimal hepatitis in 17 and mild chronic hepatitis in 16. Infection with HCV genotype Ib was found in 55.5% of patients, with a peak prevalence of 83% in children from southern Italy (P < 0.05 vs other regions). The remaining children were infected with HCV genotype la (16.6%), genotype 2 (11.1%). and mixed (10.9%) or undetermined (2.7%) genotypes. In one patient, HCV viraemia was never detected. There was no statistically significant correlation between genotype and age, sex, source of infection, alanine aminotransferase pattern and histological activity index. These results indicate that genotype 1b is widespread among Italian children with chronic hepatitis C, although with significant geographical variations. It is not associated with a more severe liver disease, therefore suggesting that the greater severity of liver disease recently reported in adults could reflect the cumulative effects of disease duration and of interfering cofactors.