High prevalence, low pathogenicity of hepatitis G virus in kidney transplant recipients

Background. Prevalence and pathogenicity of hepatitis G virus infection in long-term renal transplant recipients, are not fully known. Aim. To evaluate long-term impact of HGV infection on liver disease of rena l transplanted patients. Patients and Methods. A total of 155 hepatitis B surface antigen negative k idney transplant recipients, followed for a mean of 11 years after renal tr ansplantation, were studied. Of these 48 (31%) patients had persistently el evated serum aminotransferase values. Frozen serum samples were tested for HGV-RNA and HCV-PNA by nested reverse transcribed polymerase chain reaction , and for anti-hepatitis G virus and anti-hepatitis C virus by enzyme-linke d immunosorbent assay. Hepatitis C virus-PNA was typed by a line probe assa y and quantified by a branched DNA signal amplification assay Results. Hepatitis G virus-PNA was detected in 37 (24%) patients and anti-h epatitis G virus in another 26 (17%). Seventy (45%) patients had serum anti -hepatitis C virus and 63 of these (90%) had serum hepatitis C virus-PNA. H epatitis G virus-PNA positive and negative patients were similar in terms o f age, sex, duration of dialysis, rate of transfusion, chronic liver diseas e, rate of hepatitis C virus infection and immunosuppressive therapy. Fifte en (41%) hepatitis G virus-PNA seropositive patients were hepatitis C virus co-infected. Hepatitis C virus-PNA levels were significantly lower in the 15 hepatitis C virus/hepatitis G virus co-infected patients than in the 48 patients with hepatitis C virus infection only (2.2 vs 10.8 MEq/ml, p=0.02) . Only 3 hepatitis G virus carriers had persistently elevated alanine amino transferase compared to 29 hepatitis C virus carriers ( 14% vs 60%, p<0.001 ), 10 patients co-infected with both hepatitis G virus and hepatitis C viru s, and in 6 patients with neither infection (67% vs 8%, p<0.001). Conclusions. Hepatitis G virus infection is common among kidney transplant patients, it carries a low risk of chronic liver disease even in long-term follow-up. Low levels of hepatitis C virus-PNA found in hepatitis G virus c arriers suggest an interaction between these two viruses in immunosuppresse d patients.