Abstract Background and Objectives Platelet antibody screening and identification are crucial and challenging. MacKay Memorial Hospital has been dedicated to this for nearly four decades. We reviewed our experience with platelet antibody detection methods and prevalence, and presented a possible case of post‐transfusion purpura caused by anti‐CD36. Materials and Methods We analyzed platelet antibody screening results from 1988 to 2024. We used solid phase red cell adherence test (SPRCA) from 1988 to 2018 (9268 samples), and parallel SPRCA/enzyme‐linked immunosorbent assay (ELISA) from 2019 to 2024 (2037 samples). Positive results are further identified through flow cytometry, monoclonal antibody immobilization of platelet antigens (MAIPA), or in‐house platelet antigen panels. We also studied a possible case of post‐transfusion purpura (PTP) caused by anti‐CD36. A 79‐year‐old woman was treated with numerous platelet transfusions that were ineffective, with generalized purpura appearing a few days later following massive transfusion. Results From 1988–2018, 2800 of 9268 samples (30.2%) were positive. Six cases of neonatal alloimmune thrombocytopenia (NAITP) were identified (two anti‐HPA‐3a, two anti‐HPA‐5a, and two anti‐CD36). From 2019–2024, 778 of 2037 samples (38.19%) were positive. Specific antibodies were identified in eight cases, and six of them were anti‐CD36. Introduction of ELISA resulted in a 15‐fold detection rate of anti‐CD36 (0.02% to 0.29%), suggesting previous underestimation. In the possible PTP case, massive transfusion was started on Day 8 of hospitalization, purpura appeared on Day 15, anti‐CD36 was identified on Day 21, and CD36‐negative platelet transfusion was initiated on the following day. However, the patient eventually died of multiorgan failure on Day 29. Conclusion The prevalence of anti‐CD36 antibody in the Taiwanese population was previously underestimated. Clinicians should be aware that not only human platelet antigen (HPA) but CD36 should also be considered when platelet refractoriness persists despite HLA‐matched transfusion, as anti‐CD36 may cause serious complications.
Chen‐Yu et al. (Tue,) studied this question.