Anti-myelin oligodendrocyte glycoprotein (MOG) antibodies in patients with optic neuritis and seizures.

We describe four patients who experienced optic neuritis (ON) and seizures and were found to have antibodies to myelin oligodendrocyte glycoprotein (MOG) in serum. The index case was a previously healthy 39-year-old man who developed steroid dependent ON and had a generalized seizure when steroids were tapered. He tested positive for antibodies to MOG. We have reviewed the charts of all 11 anti-MOG antibody positive patients in our practice and found that 4 patients, all of whom had experienced one or more episodes of ON, also had a generalized seizure during the course of their illness. In 2 patients - including the index case - seizure occurred during steroid taper and in 2 others at the time of an episode of acute disseminated encephalomyelitis (ADEM). Association of anti-MOG antibodies and relapsing demyelinating disorders of the central nervous system is increasingly recognized. Testing for anti-MOG antibodies should be considered in patients with optic neuritis and seizures, especially in those with who also have a history of ADEM.