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ITP is an autoimmune disorder that can affect both adults and children.1,2 It is characterised by a severely reduced platelet count and an increased risk of bleeding, which in rare cases may be life-threatening.2,3 ITP is classified into three phases based on duration: acute (0–3 months), persistent (3–12 months) and chronic (≥12 months).2
Although traditionally considered a disorder of accelerated antibody-mediated platelet destruction, the pathophysiology of ITP also encompasses impaired platelet production.4,5 Bleeding symptoms may range from common, relatively mild events such as petechiae and bruising to rarer but more serious events such as intracranial haemorrhage.1,2 The severity of thrombocytopenia imperfectly correlates with bleeding risk; very low platelet counts are permissive but not sufficient to cause bleeding.1,5
Treatment eligibility for ITP depends not only on platelet count and bleeding tendency but also a multitude of individual patient factors (such as age, comorbidities and related treatments, lifestyle, expectations and tolerance of side effects).2 Many adults with ITP do not require treatment unless their platelet count falls below a certain level, they have significant bleeding symptoms or they need to have surgery (for any reason, including dental work).2,6 Most newly diagnosed children do not require treatment, and the condition resolves within 6–8 weeks.2,6 However, children with more severe symptoms or an increased risk of bleeding usually need some form of treatment, which tends to be the same as those used in adults.2,7
First-line treatment for ITP is corticosteroids,2,7 those with severe bleeding may also receive IV immunoglobulins to accelerate the restoration of platelet counts.2,5,8 TPO-RAs, such as REVOLADE, are recommended second-line for ITP.2,7,9 Other treatments that might be used include: romiplostim, rituximab*, avatrombopag†, azathioprine, ciclosporin A*, cyclophosphamide*, danazole*, dapsone*, fostamatinib†, mycophenolate mofetil*, and vinca alkaloids*.2,7 Patients may undergo splenectomy, however, this is only recommended for patients who are refractory to all other treatments and eligibility depends on age and comorbidities .2
*Off-label. †Not licensed in the UK.10,11
Abbreviations: ITP, immune thrombocytopenia; IV, intravenous; TPO-RA, thrombopoietin-receptor agonist.
References
- Wong RSM, et al. Blood. 2017;130(23):2527–2536.
- Provan D, et al. Blood Adv. 2019;3(22):3780–3817.
- Onisai M, et al. Rom J Intern Med. 2019. DOI: 10.2478/rjim-2019-0014. [Epub ahead of print].
- Ballem PJ, et al. J Clin Invest. 1987;80(1):33–40.
- Cines DB and Blanchette VS. N Engl J Med. 2002; 346(13):995–1008.
- Torbay and South Devon NHS Foundation Trust. Patient Information: Immune Thrombocytopenia (ITP). August 2019. Available at: https://www.torbayandsouthdevon.nhs.uk/uploads/23569.pdf (accessed December 2019).
- NICE. Immune (idiopathic) thrombocytopenic purpura: rituximab. October 2014. Available at: https://www.nice.org.uk/advice/esuom35/chapter/Key-points-from-the-evidence (accessed December 2019).
- Nomura, S. Clin Med Insights Blood Disord. 2016;6:15–22.
- REVOLADE Summary of Product Characteristics.
- NICE. Proposed technology appraisal guidance GID-TA10348. June 2018. Available at: https://www.nice.org.uk/guidance/proposed/gid-ta10348/documents (accessed December 2019).
- NICE. Proposed technology appraisal guidance GID-TA10387. August 2019. Available at: https://www.nice.org.uk/guidance/proposed/gid-ta10387/documents (accessed December 2019).