Background. Hepatitis B virus (HBV) reactivation is a well-known complication of immunosuppressive therapy. Although rituximab is increasingly used for desensitization of ABO-incompatible or positive crossmatch kidney transplantation, the risk of HBV reactivation in hepatitis B surface antigen (HBsAg)-negative/hepatitis B core antibody (anti-HBc)-positive kidney transplant patients receiving rituximab desensitization remains undetermined.

Methods. We analysed 172 resolved HBV patients who underwent living donor kidney transplantation between 2008 and 2014. Patients were divided into rituximab (n  =  49) or control (n  =  123) groups. All patients were observed for HBV reactivation, which was defined as the reappearance of hepatitis B surface antigen or HBV DNA.

Results. During the follow-up period (median, 58 months; range, 4–95 months), five patients (10.2%) in the rituximab group and two patients (1.6%) in the control group experienced HBV reactivation (P = 0.003). In the rituximab group, two patients experienced HBV-related severe hepatitis, and one patient died due to hepatic failure. The median time from rituximab desensitization to HBV reactivation was 11 months (range, 5–22 months). By contrast, no patients in the control group experienced severe hepatitis. The status of hepatitis B surface antibody was similar between groups. Rituximab desensitization [hazard ratio (HR), 9.18; 95% confidence interval (CI), 1.74–48.86; P = 0.009] and hepatitis B surface antibody status (HR, 4.74; 95% CI, 1.05–21.23, P = 0.04) were significant risk factors for HBV reactivation.

Conclusions. Rituximab desensitization for incompatible kidney transplantation significantly increased the risk of HBV reactivation in HBsAg-negative/anti-HBc-positive patients. Therefore, close monitoring of HBV DNA is required in these patients.