EFFECTS OF HEPATITIS-G VIRUS COINFECTION ON SEVERITY OF HEPATITIS-C -RELATIONSHIP TO RISK-FACTORS AND RESPONSE TO INTERFERON TREATMENT

The aims of the present study were to identify characteristics that ar e more often associated with hepatitis G virus (HGV) coinfection in Au stralian patients infected with the hepatitis C virus (HCV) and to inv estigate the effects of HGV on the histological and functional severit y of chronic hepatitis C. Serum samples from 209 patients with chronic hepatitis C were tested for HGV-RNA using single-round reverse transc riptase-polymerase chain reaction to primers directed at the NS5 regio n of the HGV genome. Hepatitis G virus RNA was detected in 40 cases (1 9%). Hepatitis G virus-coinfected patients tended to be younger and pa renteral risks could be identified in all but six. Although country of birth did not differ significantly between the coinfected and HCV-alo ne groups, HGV-positive patients appeared to be less likely to have or iginated from Asia. On logistic regression analysis, HCV genotype 3a w as found in a significantly higher proportion of patients with HGV coi nfection than other genotypes (P < 0.01). Liver histology and response to interferon were similar in the HGV-coinfected and HCV-alone groups and liver-related complications appeared to occur less frequently in patients with both HGV and HCV. On univariate analysis, antipyrine cle arance was found to be higher in the coinfected group (P < 0.05), impl ying better preservation of hepatic metabolic function, but this diffe rence was lost when adjusted for HCV genotype. In conclusion, coinfect ion with HGV was more commonly associated with HCV genotype 3a, a geno type associated with injection drug use in younger patients. However, the presence of HGV coinfection did not adversely affect liver disease or the response to interferon treatment in patients with chronic hepa titis C.