Intravenous immunoglobulin versus observation in childhood immune thrombocytopenia: a randomized controlled trial
Management of children with newly diagnosed immune thrombocytopenia (ITP) consists of careful observation or immunomodulatory treatment. Observational studies suggest a lower risk of chronic ITP in children after intravenous immunoglobulin (IVIg) treatment. In this multicenter randomized trial, children aged 3 months-16 years with newly diagnosed ITP, platelet counts ≤20 x 10(9)/L and mild to moderate bleeding were randomly assigned to receive either a single infusion of 0.8 g/kg IVIg or careful observation. Primary outcome was development of chronic ITP, at time of study initiation defined as a platelet count < 150 x 10(9)/L after 6 months. Two hundred and six children were allocated to receive IVIg (n=102) or careful observation (n=104). Chronic ITP occurred in 18.6% in the IVIg group and in 28.9% in the observation group (relative risk [RR] 0.64; 95% confidence interval [CI] 0.38-1.08). Platelet counts < 100 x 10(9)/L at 12 months (current definition of chronic ITP) were observed in 10% children in the IVIg group and in 12% in the observation group (RR 0.83; 95% CI 0.38-1.84). Complete response rates in the first three months were significantly higher in the IVIg group. IgG- Fc receptor IIb genetic variations were associated with early complete response in both groups. Grade 4-5 bleeding occurred in 9% in the observation group versus 1% in the IVIg group. IVIg treatment at diagnosis in children with ITP did not result in a lower rate of chronic ITP. In the IVIg group higher early complete response rates and less bleeding events were observed. This trial was registered at www.trialregister.nl as NTR 1563.