Changes in hepatitis B antibody status after chemotherapy in children with acute lymphoblastic leukemia

BACKGROUND: Children with cancer may be at an increased risk of infection with hepatitis B virus (HBV) when levels of hepatitis B antibodies are reduced owing to chemotherapy-induced immunosuppression. This study evaluated the changes in HBV antibody status and HBV infections after chemotherapy in children with acute lymphoblastic leukemia (ALL). PROCEDURE: The data of patients with ALL diagnosed between April 2007 and March 2013 were retrospectively collected. Hepatitis B surface antibody (HBsAb) titers were defined as negative at levels <10 IU/L. The HBsAb titers were individually compared before and after chemotherapy. RESULTS: A total of 88 patients were included in this study. At the time of diagnosis, 32 (36.4%) and 56 (63.6%) patients were HBsAb negative and HBsAb positive, respectively. The 56 HBsAb-positive patients were categorized into two groups, namely, group A with 44 patients (78.6%, 44/56) who became HBsAb negative after chemotherapy, and group B with 12 patients (21.4%) who remained HBsAb positive. On multivariate analysis, lower initial levels of HBsAb titers were associated with HBsAb negativity after chemotherapy (relative risk: 1.003, 95% confidence interval: 1.001-1.006; P = .009). CONCLUSION: This study demonstrated that patients with a low level of prechemotherapy HBsAb titers were likely to become HBsAb negative after chemotherapy. Therefore, evaluation of HBsAb status may be necessary after the completion of chemotherapy in children with ALL.