Fetal and neonatal alloimmune thrombocytopenia (FNAIT) occurs when maternal alloantibodies develop against fetal platelet antigens. FNAIT may cause severe bleeding in the fetus, including intracranial hemorrhage and long-term disabilities, especially in subsequent pregnancies. Treatments for FNAIT include fetal blood sampling with intrauterine platelet transfusions, or maternal IV immunoglobulin transfusions with or without steroids. In order to determine the best treatment strategy, researchers performed a systemic review of the literature and identified 26 studies examining FNAIT treatments (4 randomized controlled trials, 5 prospective studies, and 17 retrospective studies). Fetal blood sampling with intrauterine platelet transfusions had a complication rate of 11% with only two-thirds of the fetuses surviving. Weekly administration of IV immunoglobulin (1g/kg) was the most commonly used non-invasive procedure and also had a 98% success rate in preventing intracranial hemorrhage (N=315 pregnancies for all studies included). However, the minimum dosage needed, appropriate start time for IV immunoglobulin treatments, and the necessity of corticosteroids remain unclear.
Winkelhorst D, Murphy MF, Greinacher A, Shehata N, Bakchoul T, Massey E, Baker J, Lieberman L, Tanael S, Hume H, Arnold DM, Baidya S, Bertrand G, Bussel J, Kjaer M, Kaplan C, Kjeldsen-Kragh J, Oepkes D, Ryan G. Antenatal management in fetal and neonatal alloimmune thrombocytopenia: a systematic review. Blood 2017;129: 1538-4