Clinical onset of CNS demyelinating disease after COVID-19 vaccination: denovo disease?

BACKGROUND: Clinical onset of multiple sclerosis (MS(postvacc)) and myelin-oligodendrocyte-glycoprotein-antibody-associated disease (MOGAD(postvacc)) has been reported in association with SARS-CoV-2-vaccination. There is uncertainty as to whether this is causality (denovo disease) or temporal coincidence (manifestation of a preexisting, subclinical neuroinflammation). OBJECTIVES: Comparing the clinical characteristics of MS(postvacc)-patients versus patients with MS (PwMS) whose clinical onset occurred independently of vaccination (MS(reference)). METHODS: Consecutive patients with clinical onset ≤30 days after SARS-CoV-2-vaccination were included. Clinical data, cerebrospinal fluid (CSF) parameters and magnetic resonance imaging (MRI) as well as optical coherence tomography (OCT) data were compared to an age- and sex-matched MS(reference)-cohort. RESULTS: We identified 5 MS(postvacc) and 1 MOGAD(postvacc) patients who developed their clinical onset ≤ 30 days after SARS-CoV-2-vaccination. Clinical characteristics, CSF, MRI and OCT parameters from MS(postvacc) patients were comparable to the MS(reference) cohort and showed evidence of preexisting subclinical CNS disease. The single case with MOGAD(postvacc) clearly differed from PwMS in higher CSF cell counts, remission of MRI lesions during follow-up, and absence of oligoclonal bands. CONCLUSIONS: Our case series indicates that MS(postvacc) patients showed a rather typical initial manifestation in temporal association with SARS-CoV-2-vaccination and harbored preexisting subclinical neuroinflammation. This argues against the denovo development of MS in this cohort.