MOG-antibody associated demyelinating disease of the CNS: A clinical and pathological study in Chinese Han patients

We aim to evaluate the clinical relevance of MOG-ab in a cohort of Chinese Han adults with CNS inflammatory demyelinating diseases (IDDs). MOG-ab and AQP4-ab were examined through a fixed cell based indirect immune-fluorescence assay in 86 patients with CNS-IDDs. MOG-ab was positive in 12 patients, while AQP4-ab was positive in 31 patients; none double positives. Optic neuritis (ON) was the most frequent symptom at onset (75.0%) or during the whole disease course (83.3%) of MOG-ab associated IDDs (MOG-IDDs); 79.5% of the episodes involved only the optic nerve in MOG-IDDs. MOG-ab related ON (MOG-ON) usually caused severe visual impairment, longitudinally extensive optic nerve lesion with anterior enhancement and perineural soft tissue enhancement, responded well to steroid, but still could leave remarkable thinning of retinal nerve fiber layer (RNFL) and ganglion cell complex (GCC). MOG-IDDs had less spinal cord involvement compared to AQP4-ab mediated NMO/SD. Heterogeneous brain lesions existed in 66.7% of the patients with MOG-IDDs. Large, edematous white matter lesions were observed with the pathological feature of obvious demyelination yet preservation of astrocyte and axon, fundamentally different from the astrocytopathy typically seen in NMO/SD. Our investigations suggest that MOG-ab mediates a distinct disease entity separate from NMO/SD.