Platelet transfusion therapy: hot topics in 2021

Platelet transfusion therapy has been the object of intense research and development programs over the last 60 years. Although several evidence -based clinical practice guidelines of good quality are currently available, more stakeholder involvement in their preparation and greater attention to their applicability in the real world are needed. This short review will focus on platelet storage and platelet refractoriness, two aspects of platelet transfusion where significant advancements have occurred during the last few years, which could promote important changes in laboratory and clinical practice. Renovated interest in liquid platelet storage at 2-6 degrees C as opposed or complementary to the current standard storage at 20-24 degrees C and improved technologies for platelet cryopreservation offer the opportunity to develop more efficient platelet inventory management systems and to improve the support of actively bleeding patients, particularly those undergoing surgical procedures. Novel algorithms for the selection of human leukocyte antigen compatible platelets for a small, but not insignificant proportion of chronic platelet recipients who still develop immunological refractoriness to random donor transfusion in spite of the routine use of blood component leukoreduction could help reducing the failure of bleeding prophylaxis in onco-hematology platelet recipients. In vitro laboratory studies and clinical trials with sufficient statistical power and adequate clinical relevance are needed to confirm the existing preliminary evidences and fully exploit the recent advancements in platelet storage and in the management of alloimmune platelet refractoriness.