Neonatal Alloimmune Thrombocytopenia

Neonatal alloimmune thrombocytopenia is the most common cause of immune-mediated thrombocytopenia in the newborn period. The disorder results from placental transfer of maternal alloantibodies directed against paternally inherited antigens carried on fetal platelets. While most cases are mild, some neonates have very low platelet counts associated with serious bleeding in hours to days following birth. The treatment for severely affected neonate is typically transfusion of compatible random donor platelets in addition to intravenous immunoglobulins. The diagnosis is confirmed by genotyping of parental platelet antigens and serological testing for maternal serum antibodies. We present a newborn with early onset symptomatic thrombocytopenia, in whom early clinical recognition and prompt therapeutic intervention resulted in the complete recovery. The importance of correct diagnosis for future pregnancies isemphasized.