Myelin oligodendrocyte glycoprotein antibody-associated disease with histopathologic features of primary CNS angiitis without demyelination: Case report and literature review.

Primary angiitis of the central nervous system (PACNS) is a rare inflammatory disease that affects both small- and medium-sized vessels of the CNS, while myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD) is a novel antibody-mediated inflammatory demyelinating disorder that causes damage to the myelin in CNS. We report a case diagnosed as MOGAD due to a history of recurrent myelitis, brain lesions, and positive anti-MOG, but the brain biopsy showed vasculitis without demyelination.