Imaging and Hematologic Findings in Thrombosis and Thrombocytopenia after ChAdOx1 nCoV-19 (AstraZeneca) Vaccination.

This case series reports six patients (4 men; median age 38 years; interquartile range 26-48) presenting with vaccine-induced thrombocytopenia and thrombosis beginning 3 to 26 days after receiving the first dose of the ChAdOx1 nCoV-19 (AstraZeneca) vaccine. The patients were admitted to a general hospital between 9 to 31 days after the first dose. All patients had strongly detected anti-platelet factor 4 antibodies and severe thrombosis. Laboratory features included thrombocytopenia and elevated D-Dimer levels. Thrombotic events were predominantly venous; two patients had arterial or mixed arterial/venous thrombosis. All patients recovered after receiving intravenous immunoglobulin and non-heparin based anticoagulation.