TT virus and hepatitis G virus infections in Korean blood donors and patients with chronic liver disease

AIM:To determine the prevalences of TTV and HGV infections among blood donors and patients with chronic liver disease in Korea,to investigate the association of TTV and HGV infections with blood transfusion,and to assess the correlation between TTV and HGV viremia and hepatic damage. METHODS:A total of 391 serum samples were examined in this study.Samples were obtained from healthy blood donors(n=110),hepatitis B surface antigen(HBsAg)-positive donors(n=112),anti-hepatitis C virus(anti-HCV)-positive donors(n=69),patients with type B chronic liver disease (n=81),and patients with type C chronic liver disease(n=19). Trv DNA was detected using the hemi-nested PCR.HGV RNA was tested using RT-PCR.A history of blood transfusion and serum levels of alanine aminotransferase(ALT)and aspartate aminotransferase(AST)were also determined. RESULTS:TTV DNA was detected in 8.2%of healthy blood donors,16.1%of HBsAg-positive donors,20.3%of anti- HCV-positive donors,21.0%of patients with type B chronic liver disease,and 21.1%of patients with type C chronic liver disease.HGV RNA was detected in 1.8%of healthy blood donors,1.8%of HBsAg-positive donors,17.4%of anti-HCV-positive donors,13.6%of patients with type B chronic liver disease,and 10.5%of patients with type C chronic liver disease.The prevalence of TTV and HGV infections in HBV- or HCV-positive donors and patients was significantly higher than in healthy blood donors(P<0.05), except for the detection rate of HGV in HBsAg-positive donors which was the same as for healthy donors.There was a history of transfusion in 66.7%of TTV DNA-positive patients and 76.9%of HGV RNA-positive patients(P<0.05).No significant increase in serum ALT and AST was detected in the TTV or HGV-positive donors and patients. CONCLUSION:TTV and HGV infections are more frequently found in donors and patients infected with HBV or HCV than in healthy blood donors.However,there is no significant association between TTV or HGV infections and liver injury.

Response of TT virus to IFN plus ribavirin treatment in patients with chronic hepatitis C

AIM:TT virus (TTV) is a newly described DNA virus related to postransfusion hepatitis that produces persistent viremia in the absence of clinical manifestations.PEG-IFN plus ribavirin have been useful in the treatment of chronic hepatitis C infection.This study investigated the responses of TT virus (TTV) and hepatitis C virus (HCV) to PEG-IFN plus ribavirin therapy. METHODS:Fifteen patients infected with HCV were treated with PEG-IFN(0.5 μg/body weight/week) and ribavirin (1000 mg-1 200 mg/daily) for 48 weeks,Blood samples were drawn at the beginning and the end of the therapy.Serum TTV DNA and HCV RNA were quantified by real time PCR. RESULTS:At the beginning of treatment,TTV infection was detected in 10/15 (66.6%) of HCV-infected patients.Loss of serum TTV DNA at the end of therapy occurred in 6/10 (60%) patients.Out of these 6 patients,4 (67%) became positive for TTV DNA after 6 months of therapy.Regarding HCV viremia,11/15 (73%) patients were negative for serum HCV RNA after 48 weeks of therapy,7/11 (64%) of these cases also became negative for TTV DNA following the combined treatment.In the 3/4 (75%) patients who were positive for HCV RNA at the end of therapy,TTV DNA was detected as well.Sustained HCV response at 6 months after treatment was 53% (8/15). CONCLUSION:No TTV sustained response can be achieved in any patient after PEG-IFN plus ribavirin administration.