Pb2608: the management of immune thrombocytopenia (itp) in norway in the real life – analysis of the nor-itp registry

Topic: 32. Platelet disorders Background: Immune thrombocytopenia (ITP) is an autoimmune disorder characterized by immune-mediated platelet destruction associated with suboptimal platelet production. The management of ITP is rapidly evolving. Accordingly, it is important to know how available therapies are used in real life as well as the effectiveness and safety of these therapies. Aims: This study aimed first to describe the Norwegian ITP registry and second to determine the patterns and outcomes of ITP management in adults with ITP in Norway. Methods: We enrolled 255 adult patients from the Norwegian ITP Registry. The Norwegian ITP (NOR-ITP) Registry is a multicenter, dynamic quality control registry for children and adult ITP in Norway. Adult ITP patients are included from four participating centers in Norway. All registered patients have provided written informed consent. Results: Median age of 255 patients was 53 years, of these, 61% were females. Of these, 7% had secondary ITP at diagnosis. Almost half (44%) of the patients had bleeding at diagnosis. Skin and mucosal bleeding, together with epistaxis, were the three most frequent types of bleeding. Autoimmune disease and diabetes were the most frequent comorbidities at diagnosis. Of all patients, 15% never received treatment, whereas 205 of all treated patients (94%) received corticosteroids as first-line treatment. Eighty patients (37%) received corticosteroids as the only treatment. The median duration of treatment with corticosteroids was 4 months after 2020 compared to 6 months before 2020. The use of Intravenous immunoglobulin (IVIG) and platelet transfusion was relatively high (40% and 30% percent). The two most common second-line therapies were rituximab and TPO-RA (thrombopoietin-receptor agonist), followed by splenectomy, which was performed in 19% of the patients. Remission rate in patients who received corticosteroids as the only treatment was between 80% and 90%, depending on the type of corticosteroids. However, the remission rate in patients who received rituximab as the second-line treatment was 67% at median observation time of 46 months. Summary/Conclusion: Most of our findings are in line with data from other similar studies. A substantial proportion of patients received corticosteroids only and achieved remission. However, the median duration of treatment with corticosteroids was longer than what is recommended by the recent guidelines published in 2019. The high use of IVIG and platelet transfusion in ITP is definitely a practice that needs to be challenged. Keywords: Immune thrombocytopenia (ITP)