MANAGEMENT OF FETAL AND NEONATAL ALLOIMMUNE THROMBOCYTOPENIA

Fetal and neonatal thrombocytopenia can be induced by a maternal alloi mmunization against fetal platelet antigens. Alloimmune thrombocytopen ia occurs with an incidence of 1/1,000 livebirths and may present eith er with evidence of damage from a prenatal hemorrhage such as porencep haly or intrauterine death, or with active life-threatening bleeding d uring the neonatal period. It is due to the destruction of fetal plate lets by alloantibodies reacting on specific antigenic sites. In Caucas ians, the human platelet antigen 1a (HPA-1a) is the most frequently in volved in alloimmune thrombocytopenias, accounting for 80-90% of the c ases. Anti-HPA-Sb is responsible for a further 5-15% of the cases. Thi s article reviews the clinical aspects, the biological diagnosis and t he management, including prenatal sampling and maternal therapy.