Fetal genotyping for platelets antigens: a precise tool for alloimmune thrombocytopenia: case report and literature review

Abstract

Maternal-fetal alloimmune thrombocytopenia complicates about 0.1% of all pregnancies and is associated with major fetal and neonatal morbidity and mortality, especially spontaneous central nervous system bleeding leading to death and neurological handicaps. Successful prevention and treatment depend on the identification of at-risk possible carriers of anti-platelet antibodies. We report a case of a mother with a previous child that developed neonatal hemorrhage; HPA-5b anti-platelet antibodies were detected post-natally. During the next pregnancy, fetal genotyping confirmed the presence of HPA-5b antigen; she was treated with weekly intravenous human immunoglobulin and oral prednisone. Pregnancy evolved without remarkable features and a full-term baby was delivered, with normal platelet counts. Fetal alloimmune thrombocytopenia is a potentially lethal condition, but early detection and prevention lead to successful outcome in most cases.