MOG-IgG associated optic neuritis is not multiple sclerosis

ABSTRACT Autoantibodies against myelin oligodendrocyte glycoprotein (MOG-IgG) have been reported in patients with inflammatory central nervous system disorders including isolated optic neuritis (ON). We compared our MOG-IgG ON patients with multiple sclerosis (MS) patients presenting with ON. Methods and results: Among the total of 38 patients with optic neuropathies, six patients with isolated ON were MOG-IgG positive and eight patients with ON fulfilled the diagnostic criteria for MS. All MS patients were negative for MOG-IgG using a cell-based assay. When compared with the MS group, the MOG-IgG patients were older (mean 47 years), more frequently male (ratio 2:1) and had a higher frequency of bilateral and/or recurrent ON. The brain magnetic resonance imaging of all MOG-IgG positive patients was normal or had only unspecific white matter T2 lesions. Conclusion: These findings suggest that MOG-IgG is a biomarker of an inflammatory demyelinating CNS disease distinct from MS.