GENOTYPE DISTRIBUTION OF HEPATITIS-C VIRUS-INFECTION IN GREECE - CORRELATION WITH DIFFERENT RISK-FACTORS AND RESPONSE TO INTERFERON THERAPY

The aim of this study was to investigate the prevalence of HCV genotyp es among Greek patients with chronic hepatitis C and to assess the inf luence of genotypes and quasi-species populations on efficacy of inter feron therapy. Genotypes were determined in 65 patients (18 patients a fter kidney transplantation, 16 with thalassemia and 31 with no known risk factor) with elevated ALT for more than 6 months and histological ly proven chronic hepatitis, using the Inno-Lipa strip assay. The quas ispecies were determined using the fluorescence single-strand conforma tional polymorphism method. Most patients were infected with genotype 3a, namely 61% of patients with kidney transplants (n = 18), 50% of pa tients with thalassemia (n = 16) and 48% of patients without known ris k factors (n = 31). Other genotypes were found including coinfection w ith different genotypes. In all patients with mixed infection, genotyp e 3a was present. Thirty-six patients from the last two groups receive d interferon (3Mio U 3x week) for 1 year. Biochemical and/or virologic al and histological responses were found in 11/19 patients with genoty pe 3a (58%), 3/5 with mixed infection, 2/4 with genotype 1b, 2/5 with genotype 2a, 1/4 with genotype 1a and 1/1 with genotype 4. The virus f ound in non-responders with genotype 3a was genetically more heterogen eous than in responders. These data indicate that (1) the genotype 3a is prevalent in Greek patients (68% of all patients), (2) there is no significant difference regarding genotypes among patients with differe nt risk factors and (3) although based on a small number of patients, the genotype 3a seems to respond better to interferon therapy. Finally , the number of quasi-species may be a factor predictive of response.