Dimethyl Fumarate Was Ineffective but Not Harmful for a Patient with Myelin Oligodendrocyte Glycoprotein Antibody Disease.

We treated a myelin oligodendrocyte glycoprotein (MOG) antibody disease patient who had been prescribed dimethyl fumarate because she was thought to have been suffering from multiple sclerosis (MS). Mild optic neuritis relapsed at one year and four months after the administration of dimethyl fumarate. Therefore, dimethyl fumarate was ineffective for preventing relapse of MOG antibody disease. However, dimethyl fumarate for MOG antibody disease was not harmful compared with when disease-modifying drugs (DMDs) of MS were used for anti-aquaporin-4 antibody-positive neuromyelitis optica. If MS patients repeat relapses even after the start of DMDs, a differential diagnosis including MOG antibody disease should be made.