Abstract

Background: The clinical course of myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD) is variable. However, robust markers of poor outcome and/or relapse risk are still missing. Objective: To evaluate the frequency of cerebrospinal fluid-restricted oligoclonal bands (CSF-OCB) in a national cohort of adult MOGAD patients and to assess their prognostic value for the risk of relapse and severity. Methods: We included MOGAD adult patients fulfilling the MOGAD 2023 criteria who underwent CSF analysis at maximum 3 months from onset. Results: Data from 190 patients were collected. We found the presence of CSF-OCB in 32 patients (16.8%). Positive and negative CSF-OCB patients were similar for median age at onset, sex, clinical presentation, severity at onset, and residual disability. Relapses were more frequent in the CSF-OCB+ group ( p = 0.049), particularly within the first year of follow-up ( p = 0.007). Although CSF-OCB+ was more frequently associated with imaging features suggestive of multiple sclerosis (MS) ( p = 0.014), 78% of these patients fulfilled the 2023 supportive features and 65% experienced lesion vanishing at follow-up magnetic resonance imaging (MRI). Conclusion: We found a higher risk of relapse in MOGAD with CSF-OCB particularly during the first year. Close attention is recommended regarding the risk of misdiagnosis with MS.