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.