By Diana Aguiar de Sousa1, Jonathan Coutinho2

  1. Department of Neurosciences and Mental Health (Neurology), Hospital Santa Maria – CHULN, University of Lisbon, Lisbon, Portugal.
  2. Department of Neurology, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands

Cerebral venous sinus thrombosis (CVT) with thrombocytopenia has been recently reported after vaccination with the adenoviral-based SARS-CoV-2 vaccines ChAdOx1 nCoV-19 (AstraZeneca/Oxford) and Ad26.COV2.S (Janssen/Johnson&Johnson).

On March 19, at a press briefing on their study, a German research group announced the identification of antibodies against platelet factor 4 (PF4) in patients presenting with unusual thrombotic complications and thrombocytopenia some days after SARS-CoV-2 vaccination1.  This syndrome has been termed “vaccine-induced immune thrombotic thrombocytopenia (VITT)” but is generally termed “thrombosis with thrombocytopenia syndrome (TTS)” by the CDC and FDA. It is characterized by venous or arterial thrombosis – especially CVT – and thrombocytopenia. Most patients show PF4 antibodies in ELISA tests2,3.

As mass vaccination is a crucial step for managing the COVID-19 pandemic, collection of evidence on the characteristics and management of this rare complication is urgent. The International Cerebral Venous Thrombosis Consortium launched an international prospective registry of cerebral venous thrombosis occurring after vaccination against COVID infection. Up to now more than 90 cases were included, from hospitals all over the world. This study has been endorsed by ESO and your contribution is most welcome ( The registry includes CVT patients with radiologically confirmed CVT, with onset of CVT symptoms within 4 weeks of SARS-CoV-2 vaccination (of any type). The aim is to report clinical manifestations, laboratory findings, management, and outcome of patients with CVT after any COVID-19 vaccination.

TTS is an evolving disorder, and updates should be made as new data become available.


  1. Greinacher A, Thiele T, Warkentin TE, Weisser K, Kyrle PA, Eichinger S. Thrombotic Thrombocytopenia after ChAdOx1 nCov-19 Vaccination. N Engl J Med. Published online April 9, 2021:NEJMoa2104840. doi:10.1056/NEJMoa2104840
  2. Schultz NH, Sørvoll IH, Michelsen AE, et al. Thrombosis and Thrombocytopenia after ChAdOx1 nCoV-19 Vaccination. N Engl J Med. Published online April 9, 2021:NEJMoa2104882. doi:10.1056/NEJMoa2104882
  3. Vayne C, Rollin J, Gruel Y, Pouplard C, Galinat H, Huet O, Mémier V, Geeraerts T, Marlu R, Pernod G, Mourey G, Fournel A, Cordonnier C, Susen S. PF4 Immunoassays in Vaccine-Induced Thrombotic Thrombocytopenia. N Engl J Med. 2021 Published online May 19 2021. doi: 10.1056/NEJMc2106383.