INTRODUCTION
Immune thrombocytopenic purpura (ITP) is an autoimmune disease present with isolated thrombocytopenia (thrombocyte count < 100.000/mm3), develops due to increased thrombocyte destruction by autoantibodies, and its mostly benign, and self-limited disease. (1) The peak incidence is seen between two and 5-years of age and in 60%-80% of patients, it resolves with remission within 12 months. (2)
The incidence of ITP was reported as 7.2-9.5/100.000 per year in North America, whereas European studies reported the incidence as 2.9-5.3/100.000. (2, 4) To avoid terminological conflict in definition, the first 3 months of diagnosis is defined as “newly diagnosed ITP”, three to 12 months of disease is defined as “persistent ITP” and the disease persist over 12 months of duration is defined as “chronic ITP”.(5)
ITP pathophysiology is a very complex condition. The accused factors in ITP pathogenesis are Ab-mediated (etc. against to GPIIb-GPIIIa, GPIb-GPIX) destruction, impaired megakaryopoiesis (Ab and/or cellular destruction, slightly elevated TPO), elevated Tcell activity.(2) These Ab’s can be oligoclonal or polyclonal, and different subclass IgG families. (6)
Corticosteroids and intravenous immunoglobulin (IVIG), anti Rh D immune globulin (only Rh-positive patients) are commonly used in the treatment of ITP in children as first-line treatment options.(7-9)
The second line treatment options are anti-Rhesus-D immunoglobulin, immunosuppressive agents (azathioprine, cyclosporine, sirolimus, mycophenolate mofetil), anti-CD20 (rituximab), and several chemotherapeutics (iphosphamide, vinca alkaloids) or combinations of these options.(10, 11) Recently refractory cases are treated with thrombopoietin (TPO) receptor agonists (romiplostim, eltrombopag) and they are licensed in the treatment of ITP. (12-14)
Chronicity factors for pediatric ITP; advanced age, insidious beginning, highly (especially > 20.000/mm3) platelet numbers, and female gender.(15)
In this study, we aimed to determine the main characteristics and outcomes of our pediatric ITP cases and whether there are any risk factors affecting chronicity.