Clinical, virological and histological implications of GB virus-C/hepatitis G virus infection in patients with chronic hepatitis C virus infection: a multicentre study based on 671 patients

To determine the prevalence, as well as the clinical, virological and histological implications of GB virus C/hepatitis G virus (GBC-C/HGV) infection in patients with chronic hepatitis C virus (HCV) infection, sera from 671 well-characterized patients with chronic HCV infection were tested for GBV-C/HGV RNA using a sensitive and specific reverse transcription 'nested' polymerase chain reaction (RT-nPCR). GBV-C/HGV RNA was detected in 65 of 671 (9.7%) patients with chronic HCV infection. Importantly, GBV-C/HGV co-infection was not associated with any changes in indices of liver diseases, including serum alanine transaminase levels, Knodell score or histology activity index (HAI). In this cohort, GBV-C/HGV co-infection was weakly associated with a shorter mean estimated duration of HCV infection and a higher median HCV viraemia level. We conclude that GBV-C/HGV has minimal or no impact on liver disease activity in patients with chronic HCV infection. This data supports the notion that GBV-C/HGV may not be a hepatitis virus.