Recurrent HLA-B56 mediated neonatal alloimmune thrombocytopenia with fatal outcomes

Abstract Neonatal alloimmune thrombocytopenia is caused by maternal antibodies against paternally-inherited alloantigens present on foetal platelets and is a significant cause of morbidity and mortality in neonates. While generally thought of as a human platelet antibody mediated phenomenon, cases of HLA mediated NAIT have been reported. We document the investigation of a patient with two pregnancies affected by HLA-B56 mediated NAIT and a proposal for management of future pregnancies.