Thrombocytopenia in the Time of COVID-19 A Case-Based Discussion of Immune Thrombocytopenia (ITP) versus Vaccine-Induced Thrombotic Thrombocytopenia (VITT)

Main Article Content

Bisan Shweikialrefaee
Samantha Hershenfeld
Zachary Liederman


Immune thrombocytopenia (ITP), Vaccine Induced Thrombotic Thrombocytopenia (VITT), COVID-19


The COVID-19 infection and associated treatments, including vaccination, can lead to a multitude of hematologic complications. Both vaccine-induced thrombotic thrombocytopenia (VITT) and immune thrombocytopenia (ITP) are possible causes of thrombocytopenia following an adenoviral vector vaccine. While ITP and VITT share many similarities, they have distinct differences and require specialized treatment. Therefore it is critically important to accurately distinguish between these two vaccine-induced disorders. We report a patient who presented with ITP approximately after 1 week of COVID-19 positive diagnosis and 3 weeks after the first dose of AstraZeneca vaccine.

L’infection à la COVID-19 et les traitements qui lui sont associés, dont la vaccination, peuvent entraîner une multitude de complications hématologiques. La thrombocytopénie thrombotique induite par le vaccin (TTIV) et la thrombocytopénie immunitaire (TI) sont deux causes de thrombocytopénie qui peuvent appa-raître après avoir reçu un vaccin à vecteur adénoviral. Bien que la TI et la TTIV présentent de nombreuses similitudes, elles ont des différences marquées et exigent un traitement spécialisé. Il est donc d’une importance cruciale de les distinguer avec exactitude. Dans cet article, nous rapportons le cas d’un patient qui a présenté une TI environ une semaine après avoir reçu un diagnostic de la COVID-19 et trois semaines après avoir reçu une première dose du vaccin d’AstraZeneca.

Abstract 164 | PDF Downloads 55 XML Downloads 47 HTML Downloads 40


1. Rodeghiero F, Stasi R, Gernsheimer T, et al. Standardization of terminology, definitions and outcome criteria in immune thrombocytopenic purpura of adults and children: Report from an international working group. Blood. 2009;113(11):2386–93.
2. Amir H, Prebtani, A. COVID-19: A comprehensive overview. Can J Gen Intern Med (CJGIM). 2020;15(3):7–22.
3. Bhattacharjee S, Banerjee M. Immune thrombocytopenia secondary to COVID-19: A systematic review. SN Compr Clin Med. 2020:1–11.
4. Greinacher A, Thiele T, Warkentin TE, Weisser K, Kyrle PA, Eichinger S. Thrombotic thrombocytopenia after ChAdOx1 nCov-19 vaccination. New England J Med. 2021;384(22):2092–2101.
5. Scully M, Singh D, Lown R, et al. Pathologic antibodies to platelet factor 4 after ChAdOx1 nCoV-19 vaccination. New England J Med. 2021;384(23):2202–11.
6. Schultz NH, Sørvoll IH, Michelsen AE, et al. Thrombosis and thrombocytopenia after ChAdOx1 nCoV-19 vaccination. New England J Med. 2021;384(22):2124–30.
7. Tejpal A, Economopoulos, P., Andreou, R., Stevenson, J. Vaccine-induced immune thrombotic thrombocytopenia after receiving the ChAdOx1 nCoV-19 vaccine. Can J Gen Intern Med (CJGIM). 2020;16(2):34–7.
8. Muir K-L, Kallam A, Koepsell SA, Gundabolu K. Thrombotic thrombocytopenia after Ad26.COV2.S vaccination. N Engl J Med. 2021;384(20):1964–65.
9. See I, Su JR, Lale A, et al. US case reports of cerebral venous sinus thrombosis with thrombocytopenia after Ad26.COV2.S vaccination, March 2 to April 21, 2021. JAMA. 2021;325(24):2448-56.
10. Shah SRA, Dolkar S, Mathew J, Vishnu P. COVID-19 vaccination associated severe immune thrombocytopenia. Exp Hematol Oncol. 2021;10(1):42.
11. Wise J. COVID-19: AstraZeneca vaccine linked with small risk of ITP, real world data show. BMJ. 2021;373:n1489.
12. Tejpal A, Economopoulos, P., Andreou, R., Stevenson, J. Vaccine-induced immune thrombotic thrombocytopenia after receiving the ChAdOx1 nCoV-19 vaccine. Can J Gen Intern Med (CJGIM). 2021;16(2):34–7.13. Wong D. Johnson & Johnson COVID-19 vaccine doses coming soon, says Tam. CityNews Toronto [Internet]. [Cited 2021 Nov 5]. Available from: Accessed.
14. PKS Hwang. Where are Ontario's Johnson & Johnson vaccine doses? Frustration builds for those waiting. CBC News [Internet]. [Cited 2021 Dec 11]. Available from Accessed.
15. Canales-Lavigne M, Dove N. Single-dose Johnson & Johnson vaccine available in Sask. beginning Wednesday. Global News [Internet]. [Cited 2021 Nov 16].
16. Loft P. Covax and global access to Covid-19 vaccines. Research briefing. House of Commons Library, UK Parliament; 2022 Jan 11.
17. Bourguignon A, Arnold DM, Warkentin TE, et al. Adjunct immune globulin for vaccine-induced thrombotic thrombocytopenia. N Engl J Med. 2021 385:720-728. DOI: 10.1056/NEJMoa2107051.
18. Pishko AM, Cuker A. Thrombosis after vaccination with messenger RNA-1273: Is this vaccine-induced thrombosis and thrombocytopenia or thrombosis with thrombocytopenia syndrome? Ann Intern Med. 2021;174(10):1468–69.
19. Pavord S, Scully M, Hunt BJ, et al. Clinical features of vaccine-induced immune thrombocytopenia and thrombosis. N Engl J Med. 2021;385(18):1680–89.
20. Pishko AM, Cuker A. Diagnosing heparin-induced thrombocytopenia: The need for accuracy and speed. Int J Lab Hematol. 2021;43(Suppl 1):96–102.
21. Neunert C, Terrell DR, Arnold DM, et al. American Society of Hematology 2019 guidelines for immune thrombocytopenia. Blood Adv. 2019;3(23):3829–66.
22. Sholzberg M, Arnold DM, Laupacis A. Recognizing, managing and reporting vaccine-induced immune thrombotic thrombocytopenia. Can Med Assoc J (CMAJ). 2021;193(24):E913–15.
23. International Society of Thrombosis and Hemostasis (ISTH). Interim guidance for the diagnosis and treatment on vaccine-induced immune thrombotic thrombocytopenia. ISTH [Internet]. (Cited 2021 Apr 20). Available at:
24. Estcourt LJ, Birchall J, Allard S, et al. Guidelines for the use of platelet transfusions. Br J Haematol. 2017;176(3):365–94.
25. Das KN. Demand still strong for India-made AstraZeneca vaccine doses - COVAX's GAVI. Reuters [Internet]. [Cited 2021 Dec 9]. Available at:
26. Toltl LJ, Arnold DM. Pathophysiology and management of chronic immune thrombocytopenia: Focusing on what matters. Br J Haematol. 2011;152(1):52–60.