HBV Serologic Testing Practices and Reactivation Outcomes Before Rituximab Initiation: A Retrospective Observational Study at an Academic Tertiary Care Centre.

Background/Objectives: Hepatitis B virus (HBV) infection remains a major global health challenge because of its association with cirrhosis, hepatic failure, and hepatocellular carcinoma. Patients receiving rituximab-containing regimens are at particularly high risk for HBV reactivation due to profound B-cell depletion and prolonged immunosuppression. This study aimed to evaluate HBV serologic testing practices before rituximab initiation and to assess the incidence and outcomes of HBV reactivation among patients treated with rituximab at a tertiary care center in Jeddah, Saudi Arabia. Methods: A retrospective observational study was conducted on patients who received rituximab between 2010 and 2020 at a tertiary university hospital in Jeddah, Saudi Arabia. Demographic, clinical, laboratory, and treatment-related data were collected from electronic medical records. HBV reactivation was defined according to the American Association for the Study of Liver Diseases (AASLD) criteria. Results: A total of 611 patients were included. HBV serologic testing prior to rituximab initiation was documented in 60.8% of patients with hematological malignancies and 71.7% of those with non-hematological diseases. HBV reactivation occurred in 7 patients (3.4%) in the hematological malignancy cohort, all with lymphoma. Nine patients received antiviral prophylaxis. HBV reactivation was associated with significant morbidity, and liver-related mortality occurred in 28% of reactivation cases. Conclusions: HBV serologic testing was not universally documented prior to rituximab initiation, and antiviral prophylaxis was received by few patients. HBV reactivation was associated with significant morbidity and mortality. These findings support the need for systematic HBV evaluation and prophylaxis protocols in patients receiving rituximab.