The Challenge of Platelet Alloimmunization: Management and Prevention

ł DVANCES in our understanding of platelet .fi. function and biochemistry, transplantation and platelet immunology, and improvements in blood collection and storage technology have contributed to extraordinary improvements in platelet transfusion therapy.Platelet transfusions have permitted advances in the treatment ofleukemia, aplastic anemia, and visceral tumors by reducing the risk of thrombocytopenic hemorrhage that occurs with intensive and potentially curable levels of chemotherapy.Marrow transplantation for a variety of conditions would be impossible without the widespread availability of platelet transfusions.Despite these improvements in the transfusion support of thrombocytopenic patients, refractoriness to platelet transfusions remains a serious problem, thereby potentially limiting curative forms of therapy.This review will address current transfusion and medical practices in the management of patients refractory to platelet transfusions.In addition, promising approaches for the prevention of alloimmunization to platelet transfusions will be discussed. REFRACTORINESS TO PLATELET TRANSFUSIONSA consistent lack of response to platelet transfusions is termed platelet refractoriness.Refractoriness to platelet transfusions can be on an immune or nonimmune basis.I It should be recognized that before a patient is diagnosed as refractory to platelet transfusions, poor quality ofthe platelet transfusion must be excluded.With improved platelet storage containers and careful attention to platelet preparation, this problem has been minimized.In general the freshness of the platelet transfusion is not a signitkant cause of transfusion failures.