A case of thrombocytopenia and multiple thromboses after vaccination with ChAdOx1 nCoV-19 against SARS-CoV-2

Recently, reports of severe thromboses, thrombocytopenia, and hemorrhage in persons vaccinated with the chimpanzee adenovirus-vectored vaccine (ChAdOx1 nCoV-19, AZD1222, Vaxzevria; Oxford/AstraZeneca) against acute respiratory syndrome coronavirus 2 have emerged. We describe an otherwise healthy 30-year-old woman who developed ecchymosis, portal vein thrombosis, cerebral venous sinus thrombosis second week after she received ChAdOx1 nCoV-19 vaccine. Extensive diagnostic workup for predispositions showed heterozygosity prothrombin mutation, but no evidence myeloproliferative neoplasia or infectious autoimmune diseases. Her only temporary risk factor was long-term use oral contraceptive pills (OCPs). Although both mutation OCPs predispose to occurrence multiple thromboses within a short time associated pattern thrombocytopenia consumption coagulopathy are highly unusual. A maximum 4T heparin-induced (HIT) score positive immunoassay anti-platelet 4/heparin antibodies identified HIT as potential pathogenic mechanism. causality has not been established, our case emphasizes importance clinical awareness. Further studies this potentially new entity suggested that it should be regarded vaccine-induced immune thrombotic thrombocytopenia.