the offending antigen, so monitor platelet counts after transfusion If available, platelet products negative for the causative antigen or maternal platelets may be more effective IVIG administration may also help to boost the platelet count Consider corticosteroids for neonates who are refractory to therapy with bleeding symptoms Autoimmune neonatal thrombocytopenia can occur in infants whose mothers have primary ITP or ITP secondary to an autoimmune condition such as SLE This condition tends to result in less severe thrombocytopenia compared to NAIT Fortunately, significant bleeding episodes such as intracranial hemorrhage are rare Monitor the platelet count and provide therapy for neonates with platelet counts less than 30 to 50 × 103/μL Survival of donor platelets (platelet transfusion) is significantly shortened due to the presence of antibody Treatment with IVIG improves the platelet count in most patients Both NAIT and maternal autoantibody–mediated neonatal thrombocytopenia are self-limited as the maternal IgG antibody wanes over the course of weeks to months Heparin-Induced Thrombocytopenia Children treated with heparin are at risk for developing heparin-induced thrombocytopenia (HIT) The incidence has increased over recent years likely due to increased recognition of this entity in pediatric patients In the right clinical context, HIT is an important diagnosis to consider because it is associated with an increased risk of thrombosis and can threaten life and limb if undiagnosed The degree of thrombocytopenia, timing of the fall in platelet count relative to heparin exposure, presence of thrombosis, and other potential causes of thrombocytopenia are all important considerations when risk stratifying for the likelihood of HIT Table 93.10 presents a scheme for estimating a patient’s pretest probability of HIT