1.Introduction182.History of ITP212.1.Introduction: What is thrombocytopenic bleeding?212.2.History of bleeding222.3.History of the pathogenesis of ITP232.4.History of management of patients with ITP232.[...] therapeutic translation of IVIg to other autoimmune disorders with similarpathophysiology as in ITP252.6.Stimulation of platelet production by megakaryocytes262.7.Recent development of clinical research of ITP and new aspects of platelets [...] immunology of ITP303.1.T cell and cytokine abnormalities in ITP303.2.B cell abnormalities313.3.Dendritic Cells (DC) in ITP313.4.Environmental factors in ITP323.5.Alternative modes of thrombocytopenia in ITP333.6.Conclusions334.Megakaryopoiesis in ITP364.1.Overview of normal thrombopoiesis364.2.Thrombopoiesis in ITP: evidence for accelerated platelet destruction384.3.Thrombopoiesis in ITP: evidence for impaired platelet production394.4.Megakaryopoiesis in ITP: evidence for direct roles of megakaryocytes405.Genetics of ITP455.1.Challenges in defining a genetic etiology of ITP455.2.Germline single-nucleotide variant (SNV) candidate gene approach455.3.Familial ITP455.4.Genome-wide association studies (GWAS)465.5.Future Directions476.Differential diagnosis of ITP: Inherited Thrombocytopenias486.1.Inherited Thrombocytopenias486.1.1.Clinical and laboratory peculiarities of inherited thrombocytopenias486.1.[...] to suspect inherited thrombocytopenias546.2.Differential diagnosis between ITP and inherited thrombocytopenias556.[...] to confirm the suspicion of inherited thrombocytopenia577.Secondary ITP597.1.Definition and limitation597.2.Etiology597.3.Diagnostic workflow607.4.Genetic panel627.[...] versus children627.6.Conclusions648.Standardization of definitions, terminology and outcome criteria: a common language in ITP678.1.Criteria adopted by the IWG to harmonize terminology and definitions in ITP688.2.Primary and secondary ITP and diagnostic platelet count threshold688.3.Definition of the different phases and severity of the disease698.4.Therapeutic goals708.5.Definition of response718.6.Refractory ITP: definition, therapeutic goals and response assessment738.7.Clinical trial-adapted criteria for eligibility and outcome assessment758.8.Application of 2009 IWG proposals in real-word and need for revision758.9.Conclusions759.Decision making in the management of children with ITP809.1.A preference-sensitive decision809.2.Shared decision making819.3.[...] in childhood: a problem-oriented review of the management8410.1.Clinical presentation and diagnosis8510.2.Prevention from and therapy of bleeding8710.[...]-intervention8810.4.Intervention8810.5.Splenectomy9010.6.[...] in adulthood9311.1.Treatment of adult ITP9411.1.1.General rules9411.1.[...]-line therapy (initial treatment for newly diagnosed patients)9411.1.3.Second-line therapy9511.1.[...] second-line therapies9711.1.5.Patients failing multiple therapies9911.1.[...] second- or third- or later-line therapies in the management of adults with ITP10011.2.Conclusion10112.Management of ITP in the elderly10512.1.Diagnosis of ITP in the elderly10512.2.Treating ITP in the elderly10512.2.1.Intravenous immunoglobulins (IVIg)10612.2.2.Corticosteroids10612.2.3.Managing treatment failure and corticosteroid dependency10612.2.4.Thrombopoietin receptor agonists10612.2.5.Rituximab10712.2.6.Fostamatinib10812.2.7.Splenectomy10812.2.[...] medications10812.2.9.Investigational therapies10813.Chronic refractory ITP11013.1.Practical Considerations of Refractory ITP11013.2.Infection-related thrombocytopenia11313.[...]-induced thrombocytopenia11513.4.Secondary ITP11513.5.Therapeutic approach11613.5.1.General approach to refractory ITP11713.5.1.1.Observation11713.5.1.2.Standard therapy11713.5.1.3.Therapy for refractory disease11713.6.Outcomes and sequelae12113.7.Summary12214.Immune thrombocytopenia in pregnancy12714.1