A case of neonatal alloimmune thrombocytopenia from human platelet antigen 5b incompatibility

抄録

Anti-human platelet-specific antigen (HPA) antibody often causes neonatal alloimmune thrombocytopenia (NAIT). The antibody is produced due to the feto-maternal transfusion of incompatible platelets. In this case study, anti-HPA-5b was detected in the serum of a 30-year-old female patient. Using blood or amniotic fluid, the patient's HPA-5 phenotype was determined to be a+b-, whereas those of the husband, son and fetus were a+b+. From these findings, we concluded that there was an incompatibility of maternal and fetal HPA. Cordocentesis was performed at 34 weeks of gestation and the fetal platelet count was sufficient for vaginal delivery. A transfusion of HPA-matched platelet was prepared. The baby was delivered by vaginal delivery and there were no physical signs of thrombocytopenia.