A Case of Neonatal Alloimmune Thrombodytopenia Due to Anti - HLA Antibody

ABSTRACT

Anti-HLA antibody related neonatal thrombocytopenia is an uncommon disorder caused by platelet antigen incompatibility between mother and fetus in Korea. Mothers who lack the specific platelet antigen produce the IgG against the platelet antigen which the fetus inherits from the father. These IgG antibodies are then transported across the placenta into the fetal circulation where they lead to the destruction of fetal platelets. We report a case of neonatal alloimmune thrombocytopenia related with anti-HLA antibody in second baby of dizygotic twin who had petechia on trunk and platelet count 43,000/mm. Initially, mother and twin showed the positives in antiplatelet antibodies. In microlym- phocytotoxic test at 6 months of age, anti-HLA antibodies was negative in twins but anti-HLA A2, A24 was positive in their mother. The patient was treated with intravenous immunoglobulin and clinically improved and her platelet count was norrnalized.