Electroclinical features of seizures in myelin oligodendrocyte glycoprotein antibody-associated cerebral cortical encephalitis: A case report and literature review

Purpose: Myelin oligodendrocyte glycoprotein (MOG) antibodies (Abs) are associated with various central nervous system demyelinating disorders. Recently, they were detected in cerebral cortical encephalitis (CCE), which often causes seizures. We performed a literature review to elucidate the electroclinical features of CCE. In addition to the published cases, we describe a new, illustrative case of MOG-Ab-associated CCE (MOG-CCE) with multifocal seizures documented by video electroencephalograph (EEG).

Methods: We searched PubMed with the keywords "[MOG] AND [encephalitis]" and reviewed relevant articles. The articles included reports of patients with CCE (as demonstrated by magnetic resonance imaging) and serum MOG Ab positivity. Cases were excluded if no epileptic seizures were reported or if details of the seizures were unavailable.

Results: Our literature review identified 34 patients with MOG-CCE. An analysis of these 34 cases and the new case showed that 20 patients were male (57.1%), and the median age at presentation was 23 years (range, 6 to 46 years). Focal to bilateral tonic-clonic seizure was the most common seizure type, followed by focal motor seizure in the face or an arm or leg. EEG findings were available for 26 patients. Interictal epileptiform discharges (IEDs) and ictal EEG patterns were seen in 10 (38.5%) and 5 (19.2%) patients, respectively. Focal EEG abnormalities, including slow waves and IEDs, were observed in the central, parietal, occipital, or posterior temporal region.

Conclusion: MOG-CCE has distinctive electroclinical features that differ from those of other autoimmune encephalitides. Careful electroclinical analysis of seizures can be helpful for diagnosing MOG-CCE.