MOG antibodies in adults with a first demyelinating event suggestive of multiple sclerosis.

Abstract

MOG antibodies (MOG-Ab) distinguish multiple sclerosis (MS) from MOG-associated disease (MOGAD) in most cases. However, studies analyzing MOG-Ab at the time of a first demyelinating event suggestive of MS in adults are lacking. We aimed to 1) evaluate the prevalence of MOG-Ab in a first demyelinating event suggestive of MS, and 2) compare clinical and paraclinical features between seropositive (MOG-Ab+) and seronegative (MOG-Ab-) patients. 630 adult patients with available serum samples obtained within 6 months from the first event were included. MOG-Ab were analyzed using a live cell-based assay. Statistical analyses included parametric and non-parametric tests, logistic regression and survival models. MOG-Ab were positive in 17/630 (2.7%). 14/17 (82.4%) MOG-Ab+ patients presented with optic neuritis (ON) compared to 227/613 (37.0%) MOG-Ab-, p=0.009. CSF-restricted oligoclonal bands (CSF-OBs) were found in 2/16 (12.5%) MOG-Ab+ vs. 371/601 (61.7%) MOG-Ab-, p<0.001. Baseline brain magnetic resonance imaging (MRI) was normal in 9/17 (52.9%) MOG-Ab+ vs. 153/585 (26.2%) MOG-Ab-, p=0.029. Absence of CSF-OBs and ON at onset were independently associated with MOG-Ab positivity: Odds-Ratios (OR) 9.03; 95%Confidence Interval (95%CI) 2.04-53.6, p=0.009, and 4.17; 95%CI 1.15-19.8, p=0.042, respectively. 22.9% (95%CI 0.0-42.7) of MOG-Ab+ patients compared to 67.6% (95%CI 63.3-71.3) of MOG-Ab- fulfilled McDonald 2017 criteria at 5 years (log-rank p=0.003). MOG-Ab are infrequent in adults with a first demyelinating event suggestive of MS. However, based on our results, we suggest determining these antibodies, as long as the brain MRI is not suggestive of MS. This article is protected by copyright. All rights reserved.