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Frequency of human platelet antigens among blood donors in northeastern Thailand
Y Urwijitaroon1, S Barusrux, A Romphruk
1Blood Transfusion Centre, Faculty of Medicine, Khon Kaen University, Thailand.
Background:
Platelet transfusions have been widely used in Thailand, but little is known about the phenotyping of human platelet antigens.
Study Design And Methods:
Whole blood was collected from 483 blood donors for preparation of platelets. An improved mixed passive hemagglutination assay was used for this study.
Results:
Frequencies demonstrated were 100 percent for HPA-1a (PlA1), 15.94 percent for HPA-2b (Siba), 60.25 percent for HPA-3a (Baka), 98.76 percent for HPA-4a (Yukb), 1.86 percent for HPA-4b (Yuka), 5.38 percent for HPA-5b (Br(a)), and 97.72 percent for Naka.
Conclusion:
HPA-1a was found in 100 percent of Thais, which is the same frequency as in other Asian populations but somewhat different from that in whites (97.9%). Therefore, HPA-1a will not cause neonatal alloimmune thrombocytopenia or post-transfusion purpura in Thais. According to the frequencies of HPA-2b, HPA-3a, HPA-4a, HPA-4b, HPA-5b, and Naka antigens, they may induce neonatal alloimmune thrombocytopenia, posttransfusion purpura, and platelet refractoriness in Thais.
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