[Efficacy of rituximab in patients with EB virus-related hemophagocytic syndrome caused by B lymphocyte infection].

To explore the efficacy of rituximab in treating patients with EB virus-related hemophagocytic syndrome (EBV-HLH) caused by B lymphocyte infection. A retrospective analysis was conducted on the data of patients diagnosed with EBV-HLH, without hematopoietic stem cell transplantation and receiving rituximab treatment at Beijing Friendship Hospital, Capital Medical University from November 2021 to January 2025. All patients received treatment with a regimen containing rituximab, such as the R-DEP regimen (rituximab+liposomal doxorubicin+etoposide+methylprednisolone), the R+HLH-94 regimen (rituximab+dexamethasone+etoposide+cyclosporine), the R regimen (rituximab), and the R+P-Gemox regimen (rituximab+gemcitabine+oxaliplatin). Follow-up was conducted until August 2025 or until the patients' death to analyze the related efficacy. A total of 20 patients with EBV-HLH who received rituximab-containing regimens were enrolled. There were 11 males and 9 females, with a median age of 40 (range 5-70) years. There were 12, 5, 2, and 1 cases receiving the R-DEP, R, R+HLH-94, and R+P-Gemox regimens, respectively. The median EBV-DNA load in peripheral blood mononuclear cells before treatment was 7 000 (range 590-240 000) copies/ml. The median follow-up time [M (Q1, Q3)] was 15 (6, 24) months, the median survival time was 19 (7, 27) months, and 18 patients survived. The overall disease remission rate after treatment was 95% (19/20), and EBV-DNA was negative in 17 patients. For patients with B lymphocyte infection-related EBV-HLH, early application of a regimen centered on rituximab can effectively eliminate the virus, induce clinical remission, and improve the survival prognosis of patients.