Alloimmune thrombocytopenia of the newborn: neurodevelopmental sequelae.

Alloimmune thrombocytopenia of the newborn (AITN) is due to the transplacental passage of maternal antibodies directed against fetal platelet antigens, most commonly PLA, (HPA-1a). Sensitization and clinical manifestations of disease can occur in the first pregnancy. It carries a mortality rate of 15%, usually due to intracranial hemorrhage (ICH). Twenty-four cases of AITN were reviewed, five of whom had radiological evidence of ICH in utero. Petechiae and/or bruising were present in 14 babies. Platelet counts at birth ranged from 5 to 206 x 10(9)/L. One infant died. The duration of follow-up for the four survivors of ICH ranged from 15 to 71 months. All had serious neurodevelopmental sequelae, including severe mental retardation, cortical blindness, seizures, and cerebral palsy. The emotional and financial cost created by the care of these children is immeasurable. Steps to identify and prevent AITN should be part of routine prenatal care if we are to reduce the morbidity and mortality caused by this disorder.