Clinical Characteristics of Peripheral Lymphocyte Subtypes in Chronic Active Epstein-Barr Virus Infection

To analyze the clinical characteristics of peripheral Epstein-Barr virus(EBV)-infected lymphocyte subtypes in children with chronic active EBV infection(CAEBV).The levels of peripheral EBV infection of CD4 + T cells, CD8 + T cells, and CD56 + NK cells were determined by flow cytometry and qPCR in patients with CAEBV from July 2017 to July 2022.A total of 112 children with CAEBV were evaluated in the study. Of them, CD4 + type, CD8 + type, and CD56 + type were defined in 44, 21, and 47 patients, respectively. Patients with CD8 + T-cell type had a significantly higher frequency of rash, while hepatomegaly was more common in patients with CD4 + T-cell type. Generally, patients with CD8 + T-cell type had the lowest overall survival(OS) rate(P = 0.017). As for treatment, patients treated with chemotherapy and hematopoietic stem cell transplantation had a better prognosis(P = 0.001). In multivariate analysis, rash, HLH, CD8 + T-cell type, and no decrease of plasma EBV-DNA after treatment were indicated as independent factors of poor prognosis(P = 0.002, 0.024, 0.022, and 0.012, respectively).In children with CAEBV, the rash was more frequent in patients with CD8 + T-cell type, whereas patients with CD4 + T-cell type were more likely to develop hepatomegaly. Patients with CD8 + T-cell type had a poor prognosis despite receiving chemotherapy or further HSCT.