Effect of major ABO blood group mismatched HSCT on blood transfusion and clinical outcomes in AA patients

To investigate the impact of the ABO blood group major match type on stem cell engraftment, blood transfusion and clinical outcomes in aplastic anemia patients with hematopoietic stem cell transplantation (HSCT), we retrospectively analyzed the data of 361 aplastic anemia patients treated with HSCT, and found ABO major mismatched resulted in delayed red blood cells (RBCs) engraftment and ABO blood group conversion. The patients in the ABO major mismatched group required more units of RBCs and PLTs transfusions. Multivariate linear regression analysis showed that ABO mismatched, acute graft-versus-host disease (aGVHD), time to RBCs and PLTs engraftment and blood group conversion, and baseline hemoglobin were significantly associated with RBCs transfusion, the factors associated with PLTs transfusion were the PLTs, RBCs and neutrophils engraftment, graft rejection, baseline PLTs, aGVHD grade II-IV, and severe chronic GVHD. Multivariate analysis showed that the time to neutrophils engraftment, baseline hemoglobin, and aGVHD were independent poor prognostic factors to both overall survival and failure-free survival. Moreover, the major ABO-mismatched HSCT group were hospitalized more often. These findings suggest that it's better to select a donor with an ABO major match to reduce the burden of transfusion and the impact of hospitalization, if conditions permit.