The hepatitis B surface antigen (HBsAg)–negative and antibody to hepatitis B core antigen (anti-HBc)–positive patients after allogeneic hematopoietic stem cell transplantation (allo-HSCT) are at risk of HBV reactivation (HBVr).

To analyze the risk factors for HBVr, a total of 1,042 leukemia patients(≥18years of age), who underwent allo-HSCT from January 2016 to April 2022 in The First Affiliated Hospital of Soochow University, were enrolled in the study. Finally, 193 leukemia patients with resolved HBV infection were included into the study.

HBVr occurred in 22 patients (11.39 %), and the median time to HBVr was 24 months (with a range of 11-51months). Hepatitis flares developed in 22.73 % of patients with HBVr, and hepatic failure occurred in 1 patient. During the follow-up period, only 1(1.3 %) patient experienced HBVr among 79 patients with antiviral prophylaxis. While 21(18.42 %) patients experienced HBVr among 114 patients without antiviral prophylaxis. The cumulative incidence of HBV reactivation at 3 years was 44.4. % for anti-HBs-negative donors/recipients with a low anti-HBs titer (<100IU/L) and 7.1 % for anti-HBs-positive donors/recipients with a high anti-HBs titer (≥100IU/L) respectively. In addition, univariate and multivariate Cox regression analyses confirmed the use of rituximab as a risk factor for HBV reactivation.

The univariate and multivariate analyses confirmed that the anti-HBs titer in both recipients and donors are protective indicators to prevent incidence of HBVr. In addition, antiviral prophylaxis can significantly reduce the incidence of HBVr.