ABSTRACT
Background: Venous thromboses have been linked to several COVID-19 vaccines, but there is limited information on the Moderna vaccine's effect on the risk of arterial thrombosis. Here we describe a case of post-Moderna COVID-19 vaccination arterial infarct with vaccine-associated diffuse cortical edema that was complicated by refractory intracranial hypertension. Case Summary: 24 hrs after receiving her first dose of the Moderna COVID-19 vaccine, a 30-year-old female developed severe headache. Three weeks later she was admitted with subacute headache and confusion. Imaging initially showed scattered cortical thrombosis with an elevated opening pressure on lumbar puncture. An external ventricular drain was placed, but she continued to have elevated intracranial pressure. Ultimately, she required a hemicraniectomy, but intractable cerebral edema resulted in her death. Pathology was consistent with thrombosis and associated inflammatory response. Conclusion: Though correlational, her medical team surmised that the mRNA vaccine may have contributed to this presentation. The side effects of COVID-19 infection and vaccination are still incompletely understood. Though complications are rare, clinicians should be aware of presentations like this one.