Significant rate of hepatitis B reactivation following kidney transplantation in patients with resolved infection.

Background: Limited data is available on the risk of hepatitis B virus (HBV) reactivation in patients with resolved infection undergoing kidney transplantation. It is generally thought that this risk is negligible.

Objectives: To evaluate the incidence of HBV reactivation in such patients, and the potential risk factors for reactivation.

Study Design: Retrospective cohort study including 93 patients transplanted with a kidney between 1995 and 2007 who had evidence of resolved HBV infection (HBsAg negative, anti-HBc positive, anti-HBs positive or negative, and normal liver enzymes). HBV reactivation was defined as HBsAg reversion with HBV DNA>2000 IU/mL.

Results: Six patients experienced HBsAg reversion followed by HBV reactivation, 3 within the first post-transplant year. Immunosuppression regimen was similar in patients with and without reactivation. Among patients with reactivation only one was positive for anti-HBs antibodies at time of transplantation; these were progressively lost before reactivation. The odds ratio for reactivation in patients without anti-HBs antibodies at transplantation compared to those with anti-HBs antibodies was 26 (95% CI [2.8-240.5], p=0.0012). In patients with anti-HBs antibody titer above 100 IU/L, no reactivation was observed.

Conclusions: Reactivation rate of resolved hepatitis B is not negligible in patients without anti-HBs antibodies at transplantation. We suggest monitoring of liver tests and HBV serology including HBsAg and anti-HBs antibodies after transplantation as well as vaccination pre- and post-transplantation in all patients, including those with resolved hepatitis B, aiming at maintaining anti-HBs antibody level above 100 IU/L.