Randomized trial of high-dose methylprednisolone versus intravenous immunoglobulin for the treatment of acute idiopathic thrombocytopenic purpura in children.

Abstract

Idiopathic thrombocytopenic purpura (ITP) is an acquired disorder characterized by immune-mediated platelet destruction. The authors performed a prospective, randomized trial comparing intravenous immunoglobulin (IVIG) with high-dose intravenous methylprednisolone in the treatment of children with acute ITP. The primary aim of the study was to compare the rate of platelet increase produced by either intervention. A decision to treat was based on the clinical presentation and not an arbitrary platelet count. In general, enrolled patients exhibited extensive bruising and platelet counts less than 10 x 10 /L (10,000/microL). Seventy-seven consecutive patients, for whom the attending hematologist determined acute treatment was warranted, were studied. Forty-two patients received IVIG (1 g/kg/dose x2) and 35 received methylprednisolone (30 mg/kg/dose x3). Patients who exhibited an increase in platelet count of more than 50,000/microL after the first IVIG dose or the second methylprednisolone dose did not receive the second IVIG dose or the third methylprednisolone dose, respectively. Patients' ages ranged from 6 months to 15 years. Platelet counts were evaluated at presentation, 24, 48, 72 hours, 1 week, and 2 to 4 weeks. Eighty percent of patients treated with IVIG and 60% of patients treated with methylprednisolone demonstrated an increase in platelet count of 50,000/microL or more within 48 hours. Both IVIG and methylprednisolone therapy increased platelet counts significantly above pretreatment values. In the methylprednisolone group, the mean baseline platelet count was 4,600/microL, which rose to 14,000/microL after 24 hours, 38,000/microL after 48 hours, and 65,000/microL after 72 hours. The IVIG group had a mean baseline platelet count of 4,200/microL, which rose to 32,000/microL after 24 hours, 69,000/microL after 48 hours, and 146,000/microL after 72 hours. When compared with methylprednisolone, IVIG therapy produced a greater rise in platelet counts at 24, 48, and 72 hours, with no difference at 1 week or later time points. No serious bleeding was noted in either treatment group. Both IVIG and methylprednisolone produce a significant early rise in platelet count that is somewhat greater with IVIG. However, the higher platelet counts produced by IVIG may not justify the additional cost and potential risks of this agent.