[Cerebral cortical encephalitis with anti-myelin oligodendrocyte glycoprotein (MOG) antibody].

A 27-year-old man developed acute encephalitis with headache, fever, seizures, and aphasia. Analysis of cerebrospinal fluid showed elevated levels of cell counts and protein. A brain MRI demonstrated increased FLAIR signals in the left cerebral cortex with cortical swelling. An MRA also showed mild vasodilatation of the left middle cerebral artery branches. After admission, severe psychomotor excitement developed. Immunotherapy with intravenous high-dose steroid and subsequent oral steroid was successful, and the patient returned to premorbid working position. Repeated MRI study showed complete resolution. Serum anti-myelin oligodendrocyte glycoprotein (MOG) antibody was positive, while anti-aquaporin-4 antibody, anti-N-methyl-D-aspartate (NMDA) receptor antibody, and other autoimmune antibodies were all negative. There were no relapses at final follow-up of 8 months after onset. Cerebral cortical encephalitis with unknown etiology can occur associated with anti-MOG antibody, and anti-MOG antibody may play certain role in the pathogenesis.