Key Points• Older age, insidious onset, no preceding infection, mild bleeding, and higher platelet count are the strongest risk factors for chronic ITP.• Intravenous immunoglobulin treatment seems to protect against development of chronic ITP.Childhood immune thrombocytopenia (ITP) is a rare autoimmune bleeding disorder. Most children recover within 6 to 12 months, but individual course is difficult to predict. We performed a systematic review and meta-analysis to identify predictors of chronic ITP. We found 1399 articles; after critical appraisal, 54 studies were included. The following predictors of chronic ITP in children, assessed in at least 3 studies, have been identified: female gender (odds ratio [OR] 1.17, 95% confidence interval [CI] 1.04-1.31), older age at presentation (age ‡11 years; OR 2.47, 95% CI 1.94-3.15), no preceding infection or vaccination (OR 3.08,, insidious onset (OR 11.27,), higher platelet counts at presentation ( ‡20 3 10 9 /L: OR 2.15, 95% CI 1.63-2.83), presence of antinuclear antibodies (OR 2.87, 95% 1.57-5.24), and treatment with a combination of methylprednisolone and intravenous immunoglobulin (OR 2.67, 95% CI 1. 44-4.96). Children with mucosal bleeding at diagnosis or treatment with intravenous immunoglobulin alone developed chronic ITP less often (OR 0.39, 95% CI 0.28-0.54 and OR 0.71, 95% CI 0.52-0.97, respectively). The protective effect of intravenous immunoglobulin is remarkable and needs confirmation in prospective randomized trials as well as future laboratory studies to elucidate the mechanism of this effect. (Blood. 2014;124(22):3295-3307)
IntroductionChildhood immune thrombocytopenia (ITP) is a rare autoimmune disorder characterized by isolated thrombocytopenia (peripheral blood platelet count ,100 3 10 9 /L) in the absence of other causes that may be associated with thrombocytopenia.1 Most children present with a typical history of acute development of purpura and bruising, often after a mild viral infection. Management of newly diagnosed ITP consists of careful observation, regardless of platelet count. Severe bleeding, occurring in only 3% to 5% of children, 2 requires treatment with corticosteroids, intravenous immunoglobulin (IVIg), or anti-Rhesus-D immunoglobulin, either alone or in combination and, if life threatening, also with platelet and red blood cell transfusions. 3,4 Chronic ITP is currently defined as thrombocytopenia ,100 3 10 9 /L lasting for .12 months.1 About 20% to 25% of children with newly diagnosed ITP will develop chronic disease. Because of the high impact of ITP on a child's everyday life and activities, as well as to decide whether treatment has to be instituted to influence the clinical course of ITP, it is of clinical significance if the course of the disease could be predicted at time of diagnosis.Several clinical, therapeutic, laboratory, and genetic predictors of chronic ITP have been evaluated in children.5-7 A systematic review or meta-analysis, however, has not yet been performed. In this study, we systematically analyzed all...