The Loss of HBV-Specific Immunity in Acute Lymphoblastic Leukemia Children During Chemotherapy

Background & Aims: Chemotherapy could cause immune competence compromised, but the impact to HBV-specific immunity is poorly defined. This study aimed to evaluate the hepatitis B infection (HBV)-specific humoral immunity and the risk of HBV infection in acute lymphoblastic leukemia (ALL) children with chemotherapy in HBV highly endemic areas. Methods: Retrospective study was conducted in ALL children receiving chemotherapy from Sep, 2012 to Aug, 2018. HBV seromarker detection was performed during chemotherapy. Eligible patients were hepatitis B surface antigen (HBsAg) and hepatitis B core antibody (HBcAb)-negative before chemotherapy. Results: During chemotherapy, the percentage of protective hepatitis B surface antibody (HBsAb) had significantly decreased (from 63.0% to 37.4%); HBV infection occurred in 0.98% (4/410) of children; the detectable of HBcAb was increased to 37.7% after transfusion therapy, and then gradually disappeared. Conclusion: High proportion of children would loss the HBV-specific humoral immunity with no HBV protective antibody after chemotherapy begins. It is necessary to take seriously that clinical significance of occult HBV infection (OBI) to patients with cancer chemotherapy, especially for the risk of occult HBV to development of overt HBV infection. Clinically, there is no need to worry about the sudden appearance of HBcAb-positive, which would be the passive transfer of antibody through transfusion treatment. Funding Statement: This study was supported by the National Natural Science Foundation of China (No.81371876), National Clinical Research Center for Child Health and Disorders General Project (No. NCRCCHD-2019-GP-04), Outstanding Youth Foundation of Children's Hospital of Chongqing Medical University. Declaration of Interests: The authors declare that they have no competing interests. Ethics Approval Statement: This study was approved by the Ethics Review Committee of Children’s Hospital of Chongqing Medical University. The informed consent was obtained from all subjects or, if subjects are under 18, from a parent and/or legal guardian.