High prevalence of hepatitis G virus (HGV) infection in renal transplantation

Introduction. The newly discovered (1995) hepatitis G virus (HGV) is an RNA virus from the Flaviviridae family with 85% genomic homology to GB virus C (GBV-C). We studied the prevalence of HGV infection among a cohort of 398 renal transplant recipients (RTR), all of whom had previously received blood transfusions, been grafted between August 1984 and December 1991, and been treated by cyclosporin A (CsA) as the main immunosuppressant. Subjects and methods. According to hepatitis C virus (HCV) antibody status, and after exclusion of 28 HBs antigen-positive recipients, this cohort had previously been divided into an HCV +ve subgroup (106 RTR; 62 M vs 44 F; 29 French vs 77 non-French) and an HCV -ve subgroup (264 RTR; 181 M vs 83 F, 196 French vs 68 non-French). We randomly selected 27 RTR in the HCV+/HBV- subgroup (14 M vs 13 F, 10 French vs 17 Italians) and 27 RTR in the HCV-/HBV- subgroup (19 M vs 8 F, 18 French vs 9 Italians) for HGV screening. The detection of HGV RNA sequences in serum (viraemia) was done by double nested RT-PC-R using specific primers chosen in the 5' non-coding genomic region. The serum detection of specific antibodies (anti E2) was done by ELISA test. All sera (at time of liver biopsy or at last-follow-up) were tested in duplicate. Results. The prevalence of HGV viraemia was 26% (14/54) in the whole group and in both HCV +ve and -ve subgroups (7/27). The prevalence of HGV infection (viraemia+ and/or anti E2 antibodies+) was 44% (24/54) in the whole group and in both HCV +ve and -ve subgroups (12/27). In addition, the prevalence was similar in males vs females and in French vs foreigners recipients (mostly Italians). In the HCV +ve subgroup, the seven HGV viraemia-positive patients who previously had liver biopsies disclosed chronic active hepatitis in four (mean Knodell score 5.75) and normal livers in three, with only one case of elevated ALT (CAH 5). In the HCV- subgroup, none of the seven HGV+ viraemic patients had elevated ALT and liver biopsy was not performed. Conclusion. HGV infection prevalence is high (44%) in RTR, but clearly independent of HCV status and/or the geographical origin of the recipients. This data indicates a different epidemiology as compared to our HCVs previous experience.