Neonatal alloimmune thrombocytopenia due to a rare anti-HPA-1b antibody

Foetal and neonatal alloimmune thrombocytopenia is caused by transplacental transfer of antibodies directed against platelet antigens and affects appr oximately 1 in 1000-2500 neonates. Clinically relevant complications are th e intracranial haemorrhages that occur in 10-20% of cases. 20 platelet anti gen systems are currently known. However, immunisation is most frequently s een against two of these (HPA-1a and HPA-Sb). Treatment options include tra nsfusion of compatible or, if these are not available while urgently needed , random donor platelets, intravenous immunoglobulin, and steroids. We repo rt on a case of neonatal alloimmune thrombocytopenia, due to an anti-HPA-1b antibody in the third pregnancy of a 31-year-old Caucasoid woman. The infa nt was treated with repented maternal and random donor platelet transfusion s and with a single dose of intravenous immunoglobulin.