ABSTRACT
This chapter discusses the major hematological disorders seen in the neonatal period, especially those involving platelets, white cells, red cells, and clotting proteins. Increased destruction of platelets is seen in a number of neonatal conditions. It encompasses immune-mediated platelet destruction or consumption. Autoimmune thrombocytopenia is seen in term babies that are generally clinically well and is mediated by the passive transfer of maternal autoantibodies in mothers with autoimmune disorders such as immune thrombocytopenic purpura (ITP), systemic lupus erythematosis, and hypothyroidism. Neonatal alloimmune thrombocytopenia (NAIT) occurs following maternal sensitization to a paternally inherited fetal platelet antigen that is lacking in the mother. Increased destruction of platelets leading to thrombocytopenia may also occur from increased peripheral consumption of platelets. The inherited thrombocytopenias comprise a group of disorders in which platelet numbers are reduced. Montreal platelet syndrome is characterized by thrombocytopenia, large platelets, spontaneous platelet aggregation, and a reduced response to thrombin-induced aggregation.
