Impact of peri-transplant RBC transfusion and ABO incompatibility on acute graft-versus-host disease in pediatric hematopoietic stem cell transplant patients

It is well known that stem cell transplantation is curative for many diseases; however, graft versus host disease (GVHD), which is a common posttransplant complication, has still a substantial place among the causes of transplant-related morbidity and mortality. The association between ABO incompatibility and GVHD is controversial. There is also limited available data about the association between blood component transfusions during the peritransplant period and GVHD development in the pediatric setting. Hence, we retrospectively evaluated both the impact of ABO-mismatch and transfusions of RBC and platelets between day -7 pre-transplant and +30 post-transplant to the development of acute GVHD (aGVHD). We analyzed 139 allotransplants in 133 patients who were transplanted by myeloablative conditioning. Fifty-one patients out of 133 (36.7 %) were found to have aGVHD within +100 days post-transplantation. Of them 40 patients had grade I-II and 11 patients had grade III-IV aGVHD. Increased risk of aGVHD is associated with ABO minor mismatch (p: 0.030). Nevertheless, there was no association between ABO mismatch and severity of aGVHD. The median number of RBC transfusions in aGVHD patients was higher than the number of transfusions in patients without aGVHD; however, the difference was not statistically significant (p: 0.11). Platelet transfusion numbers were statistically similar between aGVHD patients and the patients without aGVHD (p: 0.79). In conclusion, major and bi-directional ABO-incompatibility between donors and recipients, and RBC and platelet transfusions between day -7 pretransplant and day +30 post-transplant do not contribute to aGVHD development in children undergoing HSCT by myeloablative conditioning, while ABO minor mismatch is associated with the development of aGVHD.