The challenge of platelet alloimmunization: management and prevention.

The limiting factor in platelet transfusion therapy is the development of alloimmunization. Although using HLA matched platelets may be effective in reducing the problem of alloimmune platelet transfusion refractoriness, relying solely upon HLA matching has its shortcomings. The selection of compatible platelet transfusions can be improved by compatibility testing. Despite these maneuvers, compatible platelets may not be found for some patients. When faced with these difficult patients there are few effective alternatives. The preventive measures of leukocyte depletion or ultraviolet irradiation of platelets promise to reduce or prevent alloimmunization.