Chen, John J.

Abstract Objective To report the clinical presentations and outcomes of patients with seizure and myelin oligodendrocyte glycoprotein antibody–associated disease (MOGAD). Methods We retrospectively reviewed the electronic medical records for clinical and paraclinical features among patients with seizures and MOG‐IgG (immunoglobulin G) seropositivity. Results We identified 213 patients with MOG‐IgG seropositivity who fulfilled criteria for MOGAD. Seizures attributed to central nervous system (CNS) autoimmunity were observed in 10% of patients ( n = 23: 19 children, 4 adults). The majority ( n = 19, 83%) had pediatric disease onset. Focal motor seizures were the most common seizure semiology (16/23; 70%). Focal to bilateral tonic‐clonic seizures were present in 12 patients (53%), and 3 patients (13%) developed status epilepticus. All patients had features of encephalitis at onset of seizures. Cerebral cortical encephalitis (CCE) was the most common radiological finding (10 unilateral and 5 bilateral cases). Eight of 23 patients (35%) had only CCE, six of 23 patients (26%) had only acute disseminated encephalomyelitis (ADEM), and seven of 23 patients (30%) had features of both. Fifteen patients (65%) had leptomeningeal enhancement. Three patients (13%) had coexistence of N ‐methyl‐ d ‐aspartate receptor (NMDAR) IgG. Only 3 of 23 patients (13%) developed drug‐ resistant epilepsy. Although the majority had MOGAD relapses (14/23, 60%) had only 5 of 23 patients had recurrence of episodes of encephalitis with associated seizures. Twenty‐one of 23 patients (91%) had seizure freedom at last follow‐up. Significance MOG‐IgG evaluation should be considered in patients who present with encephalitis and focal motor and/or focal to bilateral tonic‐clonic seizures, especially pediatric patients with magnetic resonance imaging (MRI) brain findings consistent with CCE, ADEM, or other MOGAD presentations. The majority of these seizures are self‐limited and do not require maintenance/chronic antiseizure medications. Although seizure recurrence is uncommon, many patients have MOGAD relapses in the form of encephalitis and optic neuritis.

ObjectivePatients with myelin oligodendrocyte glycoprotein antibody (MOG‐IgG)‐associated disease (MOGAD) suffer from severe optic neuritis (ON) leading to retinal neuro‐axonal loss, which can be quantified by optical coherence tomography (OCT). We assessed whether ON‐independent retinal atrophy can be detected in MOGAD.MethodsEighty patients with MOGAD and 139 healthy controls (HCs) were included. OCT data was acquired with (1) Spectralis spectral domain OCT (MOGAD: N = 66 and HCs: N = 103) and (2) Cirrus high‐definition OCT (MOGAD: N = 14 and HCs: N = 36). Macular combined ganglion cell and inner plexiform layer (GCIPL) and peripapillary retinal nerve fiber layer (pRNFL) were quantified.ResultsAt baseline, GCIPL and pRNFL were lower in MOGAD eyes with a history of ON (MOGAD‐ON) compared with MOGAD eyes without a history of ON (MOGAD‐NON) and HCs (p < 0.001). MOGAD‐NON eyes had lower GCIPL volume compared to HCs (p < 0.001) in the Spectralis, but not in the Cirrus cohort. Longitudinally (follow‐up up to 3 years), MOGAD‐ON with ON within the last 6–12 months before baseline exhibited greater pRNFL thinning than MOGAD‐ON with an ON greater than 12 months ago (p < 0.001). The overall MOGAD cohort did not exhibit faster GCIPL thinning compared with the HC cohort.InterpretationOur study suggests the absence of attack‐independent retinal damage in patients with MOGAD. Yet, ongoing neuroaxonal damage or edema resolution seems to occur for up to 12 months after ON, which is longer than what has been reported with other ON forms. These findings support that the pathomechanisms underlying optic nerve involvement and the evolution of OCT retinal changes after ON is distinct in patients with MOGAD. ANN NEUROL 2022;92:476–485