[Clinical analysis of opticospinal multiple sclerosis (OSMS) presentation detecting anti-myelin oligodendrocyte glycoprotein (MOG) antibody].

We report an 18 year-old-male, who had been aware of decreased visual acuity for 6 months, newly presented with paresis and sensory disturbance in his right leg. On admission, his critical flicker frequency was reduced bilaterally, and his spinal cord MRI revealed T-hyperintense lesions in cervical and thoracic cord with occasional contrast enhancements, but none of them were longitudinally extensive. There was no evidence of T-hyperintense in his brain MRI. Anti-aquapolin-4 (AQP4) antibody was negative but the patient was positive for oligoclonal bands in his cerebrospinal fluid. The patient was tentatively diagnosed as opticospinal multiple sclerosis (OSMS). However, he later tuned out to be positive for anti-myelin oligodendrocyte glycoprotein (MOG) antibody. The 2017 revised McDonald criteria don't take anti-MOG antibody into account in detail as to how clinicians should deal with patients fulfilling the MS criteria when they were also positive for anti-MOG antibody, because of its difficult problem of independence. So, we need to accumulate knowledge about these cases.