Serious thromboembolic events with concurrent thrombocytopenia have occurred very rarely following vaccination with AstraZeneca (AZ) COVID-19 vaccine. This includes venous thrombosis, sometimes involving unusual sites such as cerebral venous sinus thrombosis (CVST), splanchnic vein thrombosis, or arterial thrombosis, combined with thrombocytopenia (1).
It is currently estimated that the overall incidence of CVST following the AZ vaccine is around 4 per million first doses administered. Suspected cases have been reported in patients of all ages and genders and currently, no specific predisposing factors have been identified.
Thromboembolism with thrombocytopenia should be considered in a patient presenting to primary care between 4 and 28 days after a coronavirus vaccination with any of the following symptoms