Open questions in the treatment of immune thrombocytopenic purpura

Abstract

SUMMARY Immune thrombocytopenic purpura (ITP), also known as idiopathic thrombocytopenic purpura, is an immune-mediated acquired disease characterized by transient or persistent decrease of the platelet count. Primary ITP is defined as an autoimmune disorder characterized by isolated thrombocytopenia (peripheral blood platelet count <100x109/L) in the absence of other causes or disorders that may be associated with thrombocytopenia. Although the pathogenesis of ITP is not completely understood, the disease can be considered immune-mediated. Newly diagnosed ITP is referred to all cases within 3 months from diagnosis; persistent ITP is considered for patients with ITP diagnosed between 3 and 6 months, patients with ITP lasting more than 12 months are considered chronic ITP. Treatment is usually carried out in patients with platelet count <30 x109/L or with symptoms. Corticosteroid are the standard initial treatment and for the last 20-30 years splenectomy has been proposed as the main second line treatment. Now new medical treatments such us rituximab and thrombopoietin mimetics are available. These new drugs can offer a stable platelet count and a durable response with very mild long-term side effects that are mostly reversible and manageable. In particular for early stage patients, recent studies suggest that these therapeutic options are able to cure almost 30% of patients in this setting. Moreover, thrombopoietin mimetics switching from one agonist to another and sustained response after therapy discontinuation, are aspects of great interest to physicians.