Publication date: Jul 13, 2026
Background: Ischemic stroke has been reported rarely after coronavirus disease 2019 (COVID-19) vaccination, most clearly in association with vaccine-induced immune thrombotic thrombocytopenia (VITT). Nevertheless, temporal proximity alone cannot establish causality, particularly when conventional vascular risk factors are present. We report a case of posterior circulation ischemic stroke occurring 36-48 h after first-dose ChAdOx1 nCoV-19/AZD1222 vaccination without VITT and provide a focused narrative review of the clinical, epidemiological, and mechanistic evidence regarding post-vaccination stroke. Methods: Clinical, laboratory, and neuroimaging data were reviewed retrospectively. A focused narrative literature review was performed to contextualize VITT-related and non-VITT ischemic stroke after COVID-19 vaccination, pharmacovigilance signals, population-based evidence, and proposed biological mechanisms. Results: A 63-year-old man with well-controlled hypertension and a remote history of smoking developed systemic symptoms within 24 h of first-dose ChAdOx1 nCoV-19/AZD1222 vaccination, followed by severe hypertension and acute posterior circulation neurological symptoms 36-48 h after vaccination. Neuroimaging showed an acute left cerebellar infarct extending into the middle cerebellar peduncle, with approximately 50% stenosis of the intradural left vertebral artery. Platelet counts remained normal, D-dimer and anti-PF4 antibody testing were normal, SARS-CoV-2 polymerase chain reaction (PCR) testing was negative, and routine cardiac evaluation did not identify a definite cardioembolic source. Conclusions: This case highlights an early posterior circulation ischemic stroke temporally associated with ChAdOx1 nCoV-19/AZD1222 vaccination in the absence of VITT. Although individual causality cannot be established from a single case, careful reporting of such presentations may improve clinical recognition, etiological evaluation, and pharmacovigilance.
Semantics
| Type | Source | Name |
|---|---|---|
| disease | MESH | Ischemic Stroke |
| disease | MESH | Thrombocytopenia |
| disease | MESH | coronavirus disease 2019 |
| disease | MESH | stroke |
| disease | MESH | hypertension |
| disease | MESH | infarct |
| disease | MESH | stenosis |