Introduction We present a case of myelin-oligodendrocyte glycoprotein antibody disease (MOGAD) requiring long-term immunosuppression triggered by a dose of the AstraZeneca COVID-19 vaccination. Relapsing MOGAD is thus far an unknown complication of COVID-19 vaccination.

Case Description: A 58-year-old lady developed headache, nausea, dizziness, facial numbness, ataxia and slurred speech 8 days after the COVID-19 AstraZeneca vaccination. Her imaging showed acute disseminated encephalomyelitis (ADEM) with a white matter lesion in the left cerebellum and bilateral smaller lesions. Her cerebrospinal fluid showed 38 white cells and elevated protein. She initially responded well to steroids, however relapsed with optic neuritis 7 months later, requiring long-term immunosuppres- sion with mycophenolate mofetil.

Discussion Although there have been some case reports of MOGAD following COVID-19 infection, to our knowledge this is only the second reported case of MOGAD following vaccination against COVID-19, and the first such case to require long-term immunosuppression. The other reported case also occurred following the COVID-19 AstraZeneca vaccine, and also presented with ADEM. This is in contrast to reported cases of MOGAD following COVID-19 infection, where adults mostly presented with optic neuritis. We wanted to highlight the possibility of this vaccine-related neurological complication occurring, particularly in the context of potentially frequent ongoing COVID-19 booster vaccinations.