[Viral co-infections in hepatitis C: HBV, HBV-C/HGV and TTV studies].

BACKGROUND/AIMS: The prevalence of co-infections with hepatitis B virus (HBV) and novel hepatitis viruses GBV-C (Hepatitis G virus, HGV) and TT virus (TTV) in chronic hepatitis C (HCV) infection has been studied. In patients with chronic hepatitis C and in asymptomatic healthy HCV carriers, the influence of these agents on the course of HCV infection was assessed.

METHODS: a total of 110 HCV-positive individuals, among them 77 patients with chronic hepatitis C--50 of them treated with interferon (IFN)--and 33 HCV carriers with normal alanine aminotransferase have been investigated. HBV-DNA, HGV RNA and TTV DNA were detected by PCR, to determine HBsAg and anti-HBc ELISA technic has been used.

RESULTS: In the healthy population, the prevalence of anti-HCV was 0.3%, HBsAg 0.09%, anti-HBc 2.5%, HGV RNA 8.0% and TTV DNA 18.5%, respectively. In chronic hepatitis C HBsAg (accompanied with HBV-DNA) occurred in 1.29%, anti-HBc 25.97%, HGV RNA in 9.09% and TTV DNA in 40.25% of cases. In IFN-treated patients with sustained remission, the frequency of TTV was 20% vs. 45.7% found in non-responders. Among asymptomatic HCV-carriers, the prevalence of anti-HBc was 27.27%, HGV RNA 9.09% and TTV DNA 75.7% respectively.

CONCLUSIONS: Neither previous HBV infection, nor HGV RNA and TTV DNA had apparent effect on the course of chronic HCV infection. TTV was detected with the lowest frequency in persons with sustained remission due to IFN, suggesting antiviral effect of IFN on TTV.