Patients with vaccine-induced immune thrombotic thrombocytopaenia (VITT) following the ChAdOx1 nCoV-19 (Oxford–AstraZeneca) vaccine may present with ischaemic stroke, according to neurologists in the UK.
Clinicians at the UCL Queen Square Institute of Neurology, London, report cases of three young patients with VITT who presented with ischaemic stroke.
In one case a 35-year old woman developed symptom suggestive of stroke six days after receiving the vaccine. Imaging revealed occlusion of the right middle cerebral artery distal M1 segment with extensive ischaemia and haemorrhagic transformation. She underwent emergency decompressive hemicraniectomy but died following haemorrhagic transformation after 14 days.
The two other cases related to patients aged 37 and 43 who developed ischaemic stroke at 12 and 21 days after receiving the vaccine, in addition to venous thrombosis involving the portal and cerebral venous system. All patients showed changes in platelet count and anti-PF4 antibody assay suggestive of VITT.
Imaging showed occlusion of both internal carotid arteries and left transverse sinus thrombosis in one patient, with several acute infarcts in the right occipital lobe and centrum semiovale bilaterally. The other had an acute left frontal and insular infarct corresponding to the anterior cortical territory of the left MCA, with a small volume of haemorrhagic transformation within the infarct. Both patient received after treatments including intravenous immune globulin and fondaparinux.
Writing in the Journal of Neurology, Neurosurgery & Psychiatry, the report authors said the cases suggested that the neurological spectrum of VITT can include arterial occlusion in addition to venous thrombosis.
“Young patients presenting with ischaemic stroke after receiving the ChAdOx1 nCoV-19 vaccine should urgently be evaluated for VITT with laboratory tests (including platelet count, D-dimers, fibrinogen and anti-PF4 antibodies) and assessment for co-existing venous thromboses,” they advise.
Patients should be managed by a multidisciplinary team – including haematology, neurology, stroke, neurosurgery and neuroradiology – for rapid access to treatments, tbey said. These could include intravenous immune globulin, methylprednisolone, plasmapheresis and non-heparin anticoagulants, for example fondaparinux, argatroban, or direct oral anticoagulants.
Endovascular therapy or decompressive hemicraniectomy may also be indicated in carefully selected patients, the authors concluded.