Redenbaugh, Vyanka

Background: Data on corpus callosum involvement in myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) are limited. Objective: The objective of the study was to compare callosal lesions in MOGAD, multiple sclerosis (MS), and aquaporin-4-IgG positive neuromyelitis optica spectrum disorder (AQP4+NMOSD). Results: Callosal lesion frequency was similar in MOGAD (38/171 (22%)), MS (24/72 (33%)), and AQP4+NMOSD (18/63 (29%)). Clinical phenotypes included encephalopathy (47%) and focal supratentorial (21%) or infratentorial (45%) deficits. None had callosal-disconnection syndromes. Maximal callosal-T2-lesion diameter (median (range)) in millimeter was similar in MOGAD (21 (4–77)) and AQP4+NMOSD (22 (5–49); p = 0.93) but greater than in MS (10.5 (2–64)). Extracallosal extension (21/38 (55%)) and T2-lesion resolution (19/34 (56%)) favored MOGAD. Conclusions: Despite similar frequency and imaging overlap, larger lesions, sagittal midline involvement, and lesion resolution favored MOGAD.

Cerebral cortical encephalitis (CCE) is a recently described myelin oligodendrocyte glycoprotein antibody‐associated disease (MOGAD) phenotype. In this observational retrospective study, we characterized 19 CCE patients (6.7% of our MOGAD cohort). Headache (n = 15, 79%), seizures (n = 13, 68%), and encephalopathy (n = 12, 63%) were frequent. Magnetic resonance imaging revealed unilateral (n = 12, 63%) or bilateral (n = 7, 37%) cortical T2 hyperintensity and leptomeningeal enhancement (n = 17, 89%). N‐Methyl‐D‐aspartate receptor autoantibodies coexisted in 2 of 15 tested (13%). CCE pathology (n = 2) showed extensive subpial cortical demyelination (n = 2), microglial reactivity (n = 2), and inflammatory infiltrates (perivascular, n = 1; meningeal, n = 1). Most received high‐dose steroids (n = 17, 89%), and all improved, but 3 had CCE relapses. This study highlights the CCE spectrum and provides insight into its pathogenesis. ANN NEUROL 2023;93:297–302

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.