Neurological update: MOG antibody disease

Abstract

Myelin oligodendrocyte glycoprotein (MOG) antibody disease (MOG-AD) is now recognised as a nosological entity with specific clinical and paraclinical features to aid early diagnosis. Although no age group is exempt, median age of onset is within the fourth decade of life, with optic neuritis being the most frequent presenting phenotype. Disease course can be either monophasic or relapsing, with subsequent relapses most commonly involving the optic nerve. Residual disability develops in 50-80% of patients, with transverse myelitis at onset being the most significant predictor of long-term outcome. Recent advances in MOG antibody testing offer improved sensitivity and specificity. To avoid misdiagnosis, MOG antibody testing should be undertaken in selected cases presenting clinical and paraclinical features that are felt to be in keeping with MOG-AD, using a validated cell-based assay. MRI characteristics can help in differentiating MOG-AD from other neuroinflammatory disorders, including multiple sclerosis and neuromyelitis optica. Cerebrospinal fluid oligoclonal bands are uncommon. Randomised control trials are limited, but observational open-label experience suggests a role for high-dose steroids and plasma exchange in the treatment of acute attacks, and for immunosuppressive therapies, such as steroids, oral immunosuppressants and rituximab as maintenance treatment.

Keywords: Cerebrospinal fluid (CSF); MRI; Multiple sclerosis (MS); Myelin oligodendrocyte glycoprotein (MOG) antibodies; Neuromyelitis optica (NMO); Optic neuritis (ON).

Fig. 1

Management of MOG-AD. This proposed therapeutic management of MOG-AD is based on current evidence. Acute treatment with steroids and, if needed, subsequent plasma exchange are advised as soon as possible after an acute event. After diagnosis and, usually, acute treatment, initiation of disease-modifying therapy is advised. The choice of the disease-modifying agent should be guided by the presence or absence of poor prognostic factors for recurrence and/or disability. On this basis, treatment may require a prolonged taper with oral steroids (advised in the absence of poor prognostic factors) or the use of oral immunosuppressants or intravenous immunoglobulins along with oral steroids (advised as first choice in the presence of poor prognostic factors). If a lack of response to immunosuppressants is demonstrated or a disabling recurrence of the disease occurs after cessation of oral steroids, it is appropriate to consider monoclonal antibodies. While it is reasonable and common practice to treat relapsing patients with long-term immunosuppression, the duration of disease-modifying treatment remains uncertain. CNS central nervous system, MOG-AD myelin oligodendrocyte glycoprotein antibody disease, MOG myelin oligodendrocyte glycoprotein, IV intravenous