Azd-1222

Abstract

Immune thrombotic thrombocytopenia and malignant cerebral infarction: 2 case reports In a case series, a 57-year-old woman and a 55-year-old woman were described, who developed immune thrombotic thrombocytopenia and malignant middle cerebral artery (MCA) infarct following Azd-1222 vaccination. Subsequently, the 55-yearold woman died of MCA [dosages and routes not stated]. Patient 1: The 57-year-old woman, who had mild hypothyroidism and breast cancer, which was surgically removed in 2012 presented to emergency department 9 days after the first dose of Azd-1222 [ChAdOx1 nCoV-19 vaccine] and 1h after the onset of left hemiplegia, right gaze deviation, dysarthria and left neglect, caused by right MCA occlusion. Blood tests revealed severe isolated thrombocytopenia, therefore she did not receive IV thrombolysis and underwent successful mechanical thrombectomy after platelet transfusion. In view of a repeated MCA occlusion and worsening of the neurological symptoms, she underwent a second successful endovascular treatment after 2h. In both the procedures thrombus was collected and analysed. Unfortunately, 12h apart she developed a malignant infarct (which was an ischaemia involving the whole territory of the MCA which causes space-occupying cerebral oedema leading to rapid neurological deterioration), due to re-occlusion of the right MCA. On day 3 from stroke onset, she underwent decompressive craniectomy and betamethasone was given. Total body CT scan revealed extensive pulmonary artery and portal vein thrombosis. Her platelet count continued to decrease with a nadir of 23,000mm3. Hence, IV immune globulin was administered on days 4 and 5. Within 3 days, her platelet count increased; however, it restarted decreasing shortly after. Therefore, plasma exchange was given with a low response. When her platelet count reached to 50,000mm3, fondaparinux sodium [fondaparinux] was started. On day 11, her blood gas analysis worsened. A control thorax CT scan revealed a widespread groundglass attenuation suggestive of a severe acute respiratory distress syndrome. At the time of report, she was hospitalised in a critical condition. Patient 2: The 55-year-old woman, who had mild hypothyroidism developed abdominal pain seven days after receiving the first dose of Azd-1222 [ChAdOx1 nCoV-19 vaccine] On the morning of day 10, she presented to a first aid. Routine blood examinations were normal except for the high level of D-dimer and mild thrombocytopenia. Her abdominal ultrasound was normal. However, in the afternoon (during her hospital stay), she experienced a transient episode of aphasia and right hemiparesis, followed by generalised seizures and coma (2h later). hence, orotracheal intubation was performed. Brain CT scan, angio-CT and perfusion CT revealed occlusion of the right internal carotid artery terminus and of the left MCA, extensive ischaemic cores and severe bilateral hypoperfusion. She was transferred to emergency department. Ten hours later, a repeat blood examination revealed worsening of thrombocytopenia with a further decrease on the next day. She was treated with immune globulin and dexamethasone. Twelve-hour post-stroke a total body CT showed extensive portal vein thrombosis with occlusion of the left intrahepatic branches and left lower lobe subsegmental pulmonary arteries thrombosis. Brain CT scan revealed bilateral malignant MCA infarct with uncal herniation. Twenty four hours later, brain death was declared. Autopsy was not performed. Malignant MCA infarct was considered as cause of death.