Myelin oligodendrocyte glycoprotein antibodies: How clinically useful are they?

Serum IgG autoantibodies against the myelin oligodendrocyte glycoprotein (MOG) are present in atypical demyelinating disorders such as neuromyelitis optica spectrum disorders (NMOSD) or acute disseminated encephalomyelitis. Whereas the role of aquaporin-4 antibodies as diagnostic markers for NMOSD is meanwhile well established, the role of MOG antibodies is less clear.Initial studies suggested that MOG antibodies are associated with a more benign disease course than aquaporin-4antibodies. However, recent findings challenged this view. Data from the two largest cohorts of adult MOG antibody-positive patients with the longest clinical follow-up published so far indicate that the majority of patients develop a recurrent disease course with optic neuritis as the most frequent symptom, particularly in women. Frequent attacks are often associated with accumulating damage and functional impairment. The clinical spectrum of acquired demyelinating syndromes associated with MOG antibodies seems to be broader as anticipated in prior studies, with only a third of patients fulfilling the current diagnostic criteria for NMOSD.MOG antibodies are associated with an increasing spectrum of age and sex-dependent clinical phenotypes, only partly overlapping with NMOSD and multiple sclerosis and with a high risk of a recurrent disease course.