Wassmer, Evangeline

Objective Myelin oligodendrocyte glycoprotein antibody‐associated disease (MOGAD) can be monophasic or relapsing, with early relapse being a feature. However, the relevance of early relapse on longer‐term relapse risk is unknown. Here, we investigate whether early relapses increase longer‐term relapse risk in patients with MOGAD. Methods A retrospective analysis of 289 adult‐ and pediatric‐onset patients with MOGAD followed for at least 2 years in 6 specialized referral centers. “Early relapses” were defined as attacks within the first 12 months from onset, with “very early relapses” defined within 30 to 90 days from onset and “delayed early relapses” defined within 90 to 365 days. “Long‐term relapses” were defined as relapses beyond 12 months. Cox regression modeling and Kaplan–Meier survival analysis were used to estimate the long‐term relapse risk and rate. Results Sixty‐seven patients (23.2%) had early relapses with a median number of 1 event. Univariate analysis revealed an elevated risk for long‐term relapses if any “early relapses” were present (hazard ratio [HR] = 2.11, p < 0.001), whether occurring during the first 3 months (HR = 2.70, p < 0.001) or the remaining 9 months (HR = 1.88, p = 0.001), with similar results yielded in the multivariate analysis. In children with onset below aged 12 years, only delayed early relapses were associated with an increased risk of long‐term relapses (HR = 2.64, p = 0.026). Interpretation The presence of very early relapses and delayed early relapses within 12 months of onset in patients with MOGAD increases the risk of long‐term relapsing disease, whereas a relapse within 90 days appears not to indicate a chronic inflammatory process in young pediatric‐onset disease. ANN NEUROL 2023;94:508–517

Background Steps towards the development of diagnostic criteria are needed for children with the radiologically isolated syndrome to identify children at risk of clinical demyelination. Objectives To evaluate the 2005 and 2016 MAGNIMS magnetic resonance imaging criteria for dissemination in space for multiple sclerosis, both alone and with oligoclonal bands in cerebrospinal fluid added, as predictors of a first clinical event consistent with central nervous system demyelination in children with radiologically isolated syndrome. Methods We analysed an international historical cohort of 61 children with radiologically isolated syndrome (≤18 years), defined using the 2010 magnetic resonance imaging dissemination in space criteria (Ped-RIS) who were followed longitudinally (mean 4.2 ± 4.7 years). All index scans also met the 2017 magnetic resonance imaging dissemination in space criteria. Results Diagnostic indices (95% confidence intervals) for the 2005 dissemination in space criteria, with and without oligoclonal bands, were: sensitivity 66.7% (38.4–88.2%) versus 72.7% (49.8–89.3%); specificity 83.3% (58.6–96.4%) versus 53.9% (37.2–69.9%). For the 2016 MAGNIMS dissemination in space criteria diagnostic indices were: sensitivity 76.5% (50.1–93.2%) versus 100% (84.6–100%); specificity 72.7% (49.8–89.3%) versus 25.6% (13.0–42.1%). Conclusions Oligoclonal bands increased the specificity of magnetic resonance imaging criteria in children with Ped-RIS. Clinicians should consider testing cerebrospinal fluid to improve diagnostic certainty. There is rationale to include cerebrospinal fluid analysis for biomarkers including oligoclonal bands in planned prospective studies to develop optimal diagnostic criteria for radiologically isolated syndrome in children.