RESPONSIVENESS TO INTERFERON-ALPHA TREATMENT IN PATIENTS WITH CHRONICHEPATITIS-C COINFECTED WITH HEPATITIS-G VIRUS

Background/Aims: Patients with chronic hepatitis C are often coinfecte d with the new identified Flaviviridae-like agent, termed hepatitis G virus (HGV), The aim of the study was to investigate the responsivenes s of hepatitis G virus to interferon alpha and to evaluate whether a h epatitis G virus coinfection negatively influences the outcome of trea tment in chronic hepatitis C, Methods: One hundred and fifteen patient s with histologically proven chronic hepatitis C were treated with int erferon alpha and investigated for the presence of hepatitis G virus c oinfection by nested polymerase chain reaction with primers from the h elicase region of hepatitis G virus, All patients received at least 3 MU (range 3-6) interferon alpha thrice weekly for at least 6 months (m ean 8, range 6-12), Polymerase chain reaction products of seven pre- a nd post-treatment hepatitis G virus positive patients were directly se quenced for identification of sequence variability during the follow-u p, Results: Eighteen (16%) patients were coinfected with hepatitis G v irus, Although nine (50%) of these patients became HGV RNA negative du ring interferon alpha therapy, only three patients (17%) remained HGV RNA negative at the end of follow-up (mean 24 months), The rate of sus tained response of chronic hepatitis C was not significantly different between patients with hepatitis C virus infection and HCV/HGV coinfec tion (19% vs 28%), Severity of liver disease as determined by alanine aminotransferase levels, histology and hepatitis C virus viremia was n ot significantly different in patients with hepatitis C virus or HCV/ HGV coinfection, Sequence analysis of the helicase region revealed tha t our isolates all belonged to the hepatitis G virus and not to the GB V-C like genotype, No amino acid exchanges during the observation peri od of up to 48 months were observed, indicating that this region is hi ghly conserved, Conclusions: The responsiveness of hepatitis G virus t o interferon alpha in chronic HCV/HGV coinfected patients is similar t o that observed in chronic hepatitis C, Hepatitis G virus coinfection seems not to interfere with the efficacy of interferon alpha treatment in patients with chronic hepatitis C.