Does hepatitis C virus affect the reactivation of hepatitis B virus following renal transplantation?

BACKGROUND: Hepatitis B virus (HBV) is endemic in Taiwan. Transplantation followed by long-term immunosuppressive medications may precipitate HBV reactivation. Interference of hepatitis C virus (HCV) with HBV gene expression and replication has been confirmed in many studies involving non-transplant populations. This study investigates the incidence of HBV reactivation following renal transplantation and compares the clinical outcome, especially the liver outcome, of patients with or without HCV co-infection. METHODS: Fifty-one of 512 renal transplant recipients were positive for hepatitis B surface antigen before surgery, and were followed for 81.6+/-7.5 (4-120) months. Seventeen of 51 patients acquired HCV before transplantation and six patients acquired HCV after renal transplantation. RESULTS: At the end of this assessment, we had 28 patients who suffered HBV reactivation and another 23 patients who suffered no HBV reactivation. Initially, we found a significant difference of HCV carriage (P<0.05) between patients with (seven out of 28 or 25%) or without (21 out of 23 or 91.3%) HBV reactivation. Further inspection showed that 21 of the 28 patients without HCV co-infection and seven of the 23 patients with HCV co-infection suffered HBV reactivation. After comparison, we found a lower incidence of HBV reactivation in patients with HCV co-infection than in patients without HCV co-infection (P<0.05). In contrast to the latter, we found that patients with HCV co-infection suffering HBV reactivation tended to have a late onset of HBV reactivation (P<0.05). Otherwise, there was no difference in hepatitis severity, in terms of peak alanine aminotransferase, total bilirubin levels and hepatitis reactivation-related death, between these two groups of patients. Finally, a multivariable analysis also revealed that HCV carriage was indeed an independent variable leading to the reduced incidence of HBV reactivation in patients with HCV co-infection. CONCLUSION: HCV might affect the reactivation of HBV by decreasing the incidence or delaying the onset of HBV reactivation in renal transplant recipients carrying both HBV and HCV.