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drugs that interfere with platelet function such as aspirin and NSAIDs, as well as activities that increase the risk of head injury TABLE 93.8 BUCHANAN AND ADIX BLEEDING SEVERITY FOR CHILDREN WITH ITP Overall bleeding severity Score Description None Definitely no new hemorrhage of any kind Minor Few petechiae (≤100 total) and/or ≤5 small bruises (≤3 cm diameter) Mild Many petechiae (>100 total) and/or >5 large bruises (>3 cm diameter); no/minimal mucosal bleeding Moderate Overt mucosal bleeding (epistaxis, gum bleeding, oropharyngeal blood blisters, menorrhagia, gastrointestinal bleeding, etc.) that does not require immediate medical attention or intervention Severe Mucosal bleeding or suspected internal hemorrhage (in the brain, lung, muscle, joint, etc.) that requires immediate medical attention or intervention Life threatening Documented intracranial hemorrhage or life-threatening or fatal hemorrhage in any site Reproduced with permission from Buchanan GR, Adix L Grading of hemorrhage in children with idiopathic thrombocytopenic purpura J Pediatr 2002;141:683–688 Adjuvant therapies to control bleeding for the patient with ITP, as outlined in Table 93.2 , may be of use until specific ITP treatments are effective Nasal packing and topical phenylephrine are useful for persistent epistaxis Excessive menstrual bleeding may require hormonal therapy Antifibrinolytics may be useful in decreasing mucocutaneous bleeding Intractable symptoms warrant hematology consultation for consideration of second-line or extraordinary measures Management of Head Trauma Intracranial hemorrhage in the setting of ITP is rare, but it is also the major cause of mortality in ITP and therefore requires immediate recognition and intervention Figure 93.4 provides an algorithm for managing head trauma in the setting of ITP No universally accepted guideline for the evaluation and management of head trauma in ITP patients exists Carefully consider each case and manage in conjunction with hematology Clinical Indications for Discharge or Admission Many patients with ITP can be managed on an outpatient basis Consider age, developmental level, parental comfort, and distance from the hospital when identifying patients who are safe for discharge with close outpatient follow-up TABLE 93.9 TREATMENT REGIMENS FOR ACUTE ITP Treatment Corticosteroids IVIG Rho (D) immune globulin (WinRho) Treatment regimen Prednisone or g/kg IV × 1–2 doses prednisolone mg/kg BID × days OR mg/kg/day × 10 days Max dose: 40 mg BID 50 mcg/kg IV initial dose, subsequent doses based on response and hemoglobin level Benefits • Enteral • Outpatient therapy • Inexpensive • Emotional instability • Hyperphagia • Hyperactivity • If diagnosis incorrect, potential to partially treat ALL • Fastest rise of platelet count • Steroid sparing • Short infusion time • Steroid sparing • Hypersensitivity reaction • Severe headache • Aseptic meningitis • Fever/chills • Immune mediated • Hemolysis • Long infusion time • Expensive • Only for Rh+ patients • Black box warning: lifethreatening acute/subacute immunemediated intravascular hemolysis • Fever/chills Risks/side effects FIGURE 93.4 ITP with head trauma or concern for CNS bleed OTHER DISORDERS ASSOCIATED WITH THROMBOCYTOPENIA Neonatal Thrombocytopenia Thrombocytopenia can arise in neonates from a number of different etiologies: immune mediated, perinatal asphyxia, inherited thrombocytopenias, drug/medication toxicity, and infection Careful assessment of the clinical status of the neonate as well as the timing of the thrombocytopenia can help narrow the differential diagnosis The two most common immune-mediated causes are neonatal alloimmune thrombocytopenia (NAIT) and autoimmune neonatal thrombocytopenia NAIT can emerge in an otherwise healthy neonate and can lead to significant morbidity and mortality if unrecognized NAIT develops when a fetus expresses a paternally inherited antigen on its platelets that the mother does not Maternal exposure to these fetal platelets generates an IgG antibody that can cross the placenta and cause destruction of fetal platelets and megakaryocytes This can occur with a first pregnancy and often more severely with subsequent pregnancies When recognized, it is an indication for future high-risk obstetrical care Severe thrombocytopenia leads to increased risk of intracranial hemorrhage Maintaining the platelet count greater than 30,000/μL during the first week of life and greater than 20,000/μL subsequently is appropriate in nonbleeding infants Greater than 50,000/μL is the goal in the setting of bleeding Random donor platelet transfusion may be ineffective if those platelets carry 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  ... 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