Objective: To explore the value of CD3+CD4+ T cell count in prediction of viral infections after allogeneic hematopoietic stem cell transplantation(allo-HSCT) in the patients with severe aplastic anemia(SAA).
Methods: A total of 78 SAA patients with allo-HSCT in Guangzhou First People's Hospital from January 2014 to July 2016 were enrolled in this study. The absolute numbers of CD3+CD4+T cells were measured by flow cytometry at 1,2,3,6, and 12 month after allo-HSCT. According to the cell counts, the patients were divided into 3 groups: i.e. <50/µl (n=120), 50-100/µl(n=48) and >100/µl(n=123)groups. The infection incidences of human cytomegalovirus (HCMV) and Epstein-Barr virus(EBV) within 2 weeks around each time point were compared between different groups. According the counts of CD3+CD4+T cells at 3 months after-transplant, these patients were divided into 2 groups, i.e.>100/µl (n=30) and ≤100/µl (n=48). The incidences and duration of HCMV and EBV infection, overall survival rate were compared between 2 groups.
Results: The incidences of CMV and EBV infection significantly decreased in CD3+CD4+ T cell >100/µl group as compared with <50/µl and 50-100/µl groups. At 3 months after-transplant, there was lower incidence rates of CMV disease, EBV infection, shorter durations of CMV infection and better survival in CD3+CD4+ T cell >100/µl group as compared with ≤100/µl group.
Conclusion: CD3+CD4+ T cell count is a good predictor for CMV and EBV infection after allo-HSCT in SAA patients. There are low risk of infe-ctions from CMV and EBV when CD3+CD4+ T cell count >100/µl in any time after transplant, which means lower occurrence of CMV and EBV infection and better survival when CD3+CD4+ T cell counts is >100/µl in 3 months after transplant in SAA patients.