Transfusion of ABO non-identical platelets does not influence the clinical outcome of patients undergoing autologous haematopoietic stem cell transplantation.

Background. There are ABO antigens on the surface of platelets, but whether ABO compatible platelets are necessary for transfusions is a matter of ongoing debate. We retrospectively reviewed the ABO matching of platelet transfusions in a subset of patients undergoing autologous haematopoietic progenitor cell transplantation during a 14-year period. Our aim was to analyse the characteristics and outcomes of patients who received platelet transfusions that were or were not ABO identical. Material and methods. We analysed 529 consecutive patients with various haematological and non-haematological diseases who underwent 553 autologous progenitor stem cell transplants at the University Hospital la Fe between January 2000 and December 2013. We retrospectively analysed and compared transfusion and clinical outcomes of patients according to the ABO match of the platelet transfusions received. The period analysed was the time from transplantation until discharge. Results. The patients received a total of 2,772 platelet concentrates, of which 2,053 (74.0%) were ABO identical and 719 (26.0%) ABO non-identical; of these latter 309 were compatible and 410 incompatible with the patients' plasma. Considering all transplants, 36 (6.5%) did not require any platelet transfusions, while in 246 (44.5%) cases, the patients were exclusively transfused with ABO identical platelets and in 47 (8.5%) cases they received only ABO non-identical platelet transfusions. The group of patients who received both ABO identical and ABO non-identical platelet transfusions had higher transfusion needs and worse clinical outcomes compared to patients who received only ABO identical or ABO non-identical platelets. Discussion. In our hospital, patients undergoing autologous haematopoietic stem cell transplantation who received ABO identical or ABO non-identical platelet transfusions had similar transfusion and clinical outcomes. The isolated fact of receiving ABO non-identical platelets did not influence morbidity or survival.