Meningo-cortical manifestations of myelin oligodendrocyte glycoprotein antibody-associated disease: Review of a novel clinico-radiographic spectrum

Abstract

Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is an inflammatory demyelinating disease that is distinct from multiple sclerosis. Initial manifestations of MOGAD that were reported in the literature included optic neuritis, myelitis, brainstem demyelination and encephalitis, with emphasis placed on acute disseminated encephalomyelitis (ADEM) as the primary encephalitic presentation. In 2017, however, Ogawa et al. described four patients with seizures, unilateral cortical hyperintensities on brain magnetic resonance imaging T2-fluid-attenuated inversion recovery sequences, and anti-MOG positivity, indicating a potentially novel form of encephalitis in MOGAD. In 2019, we systematically reviewed the literature to better characterize this unique syndrome, which we referred to as unilateral cortical FLAIR-hyperintense Lesions in Anti-MOG-associated Encephalitis with Seizures (FLAMES). Subsequently, anti-MOG positivity in patients with a variety of cortical and meningeal disease presentations has been reported, indicating a broader spectrum of meningo-cortical manifestations in MOGAD that we review herein.

FLAIR-hyperintense lesions in anti-MOG-associated encephalitis with seizures overlaying anti-N-methyl-D-aspartate receptor encephalitis: a case report and literature review

“…In accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we searched the PubMed database for publications up to September 15, 2022 that contained the terms "NMDAR" and "MOG", or "NMDAR" and "Demyelination" and "MOG" and "Encephalitis", in order to identify articles reporting on patients with coexisting FLAMES and anti-NMDARe (Figure 1). The inclusion criteria were as follows: (1) patients were positive for anti-NMDAR antibodies in the CSF and MOG antibodies in the serum; (2) the course of the disease included an episode of FLAMES; and (3) complete data were available on clinical symptoms, imaging, and treatment. Patients lacking a detailed clinical course description or radiological and laboratory information were excluded from the study.…”

“…The term “FLAIR-hyperintense lesions in anti-MOG-associated encephalitis with seizures” (FLAMES) was introduced by Budhram in 2019. Although this was initially reported as unilateral cortical encephalitis, the presence of bilateral cortical involvement and meningeal inflammation in a subset of cases suggests a broader disease spectrum ( 2 ). Atypical manifestations of demyelination, such as fever, headache, epilepsy, and aphasia, are common in FLAMES.…”

MRI to differentiate multiple sclerosis, neuromyelitis optica, and myelin oligodendrocyte glycoprotein antibody disease

“…Uni‐ or bilateral thalamic and basal ganglia lesions are more common in MOGAD than AQP4‐ab‐positive NMOSD and MS 65,68,79 . A different cortical lesion pattern in MOGAD patients associated with seizures is apparent in FLAIR sequences and such clinicoradiological syndrome is known as FLAIR hyperintense lesions in anti‐MOG encephalitis with seizures 59,80–82 . As mentioned above, cortical/juxtacortical lesions were observed in most MS patients, in a minority of MOGAD patients, and in none of AQP4‐ab‐positive NMOSD patients in a study recently published 31 …”

Clinical characteristics of patients with myelin oligodendrocyte glycoprotein antibodies

“…New phenotypes are recently been reported, and could be considered as forme fruste of CCE [45 ▪▪ ]. It included a spectrum from aseptic meningitis to isolated intracranial hypertension.…”

“…By definition, the complete work-up for infectious aetiology is negative. A recent review proposed to incorporate these presentations to CCE, under the term of ‘meningo-cortical manifestations’ [45 ▪▪ ]. The proposal is convincing as, at follow-up, most of isolated aseptic meningitis cases present parenchymal brain lesions and/or experienced CCE or classical MOGAD phenotype (i.e.…”