POSTTRANSFUSION PURPURA-LIKE SYNDROME-ASSOCIATED WITH CD36 (NAK(A)) ISOIMMUNIZATION

Background: CD36 deficiency, which could lead to CD36 isoimmunization, has been reported in the Japanese population. CD36 isoantibody has be en involved in platelet transfusion refractoriness. Case Report: A 50- year-old woman originally from Corsica developed severe acute thromboc ytopenia after massive transfusion. She was found to be CD36 deficient , and platelet immunoassays revealed a CD36 (Nak(a)) platelet isoantib ody. Although the involvement of another mechanism could not be entire ly ruled out, the thrombocytopenia was attributed to posttransfusion p urpura-like syndrome. The antibody was also involved in platelet trans fusion refractoriness. CD36 deficiency was present in two members of t he patient's family as well. Flow cytometry studies demonstrated the a bsence of CD36 expression on the surface of blood monocytes and cultur ed erythroblasts and megakaryocytes from one of the two CD36-deficient family members studied, but, in the absence of previous immunization, these CD36-deficient patients were not isoimmunized. In contrast, CD3 6 deficiency was not found in a population of 808 healthy blood donors in the Paris, France, area. Conclusion: CD36 isoantibody might be inv olved in some cases of posttransfusion purpura and platelet transfusio n refractoriness. These findings also confirm the extremely low freque ncy of CD36 deficiency among whites.