Manifestations of MOG-IgG-positive optic neuritis are diverse. Despite recurrent attacks with severe vision loss, the majority of patients have significant recovery and retain functional vision long-term.

IMPORTANCE Recent studies have reported a higher relapse rate following an initial inflammatory demyelinating disorder in pediatric patients with persistent seropositivity of antibodies targeting myelin oligodendrocyte glycoprotein (MOG-IgG1). To date, the clinical implications of longitudinal MOG-IgG1 seropositivity using live cell assays with IgG1 secondary antibodies in adults after acute disseminated encephalomyelitis (ADEM) are unknown. OBJECTIVE To determine whether MOG-IgG1 serostatus (transient vs persistent) and titer change over time provide clinical utility in predicting the likelihood of relapse after ADEM. DESIGN, SETTING, AND PARTICIPANTS This cohort study identified patients with an initial diagnosis of ADEM evaluated at a single referral center between January 1, 1990, and October 1, 2017. Fifty-one patients were included, including 31 children and 20 adults. Longitudinal serologic testing was performed detecting autoantibodies targeting aquaporin 4 (AQP4-IgG) and MOG-IgG1 with clinically validated fluorescence-activated cell sorting assays. Patients were divided into 3 cohorts: persistent seropositivity, transient seropositivity, and seronegativity. MAIN OUTCOMES AND MEASURES Clinical demographic characteristics, longitudinal AQP4-IgG and MOG-IgG1 serostatus, titers, relapses, use of immunotherapy, and Expanded Disability Status Scale score at follow-up. RESULTS Of 51 patients presenting with an initial diagnosis of ADEM, 20 (39%) were adult, 24 (47%) were female, and ages ranged from 12 months to 57 years. Seventeen patients fulfilled criteria for persistent seropositivity; of those, 8 of 9 children (89%) and 7 of 8 adults (88%) had at least 1 relapse after median (range) follow-up periods of 75 (15-236) months and 39 (9-161) months, respectively. Eight patients (16%), including 4 adults, fulfilled criteria for transient seropositivity; of those, no children and 1 of 4 adults (25%) relapsed after median (range) follow-up periods of 32 (24-114) months and 16 (13-27) months, respectively. Of 24 patients with AQP4-IgG and MOG-IgG seronegativity, 6 of 17 children (35%) and 2 of 7 adults (29%) had at least 1 relapse after median (range) follow-up periods of 36 (3-203) months and 34 (15-217) months, respectively. There were only 2 patients, including 1 adult, with AQP4-IgG seropositivity, and both relapsed. The hazard ratio for relapses in those with persistent MOG-IgG1 positivity compared with AQP4-IgG and MOG-IgG1 seronegativity was 3.1 (95% CI, 1.1-8.9; P = .04) in children and 5.5 (95% CI, 1.4-22.5; P = .02) in adults. Immunotherapy was used in 5 of 9 children (56%) and 6 of 8 adults (75%) with persistent seropositivity and in 3 of 17 children (18%) and 1 of 7 adults (14%) with AQP4-IgG and MOG-IgG seronegativity. CONCLUSIONS AND RELEVANCE Relapse occurred in 15 of 17 patients (88%) with persistent MOG-IgG1 seropositivity after ADEM; only 1 patient with transient seropositivity experienced relapse. Our data extend the clinical utility of MOG-IgG1 serological testing to adult patients and highlight...

ObjectiveMyelin oligodendrocyte glycoprotein–immunoglobulin G (MOG-IgG) associated disorder (MOGAD) often manifests with recurrent CNS demyelinating attacks. The optimal treatment for reducing relapses is unknown. To help determine the efficacy of long-term immunotherapy in preventing relapse in patients with MOGAD, we conducted a multicenter retrospective study to determine the rate of relapses on various treatments.MethodsWe determined the frequency of relapses in patients receiving various forms of long-term immunotherapy for MOGAD. Inclusion criteria were history of ≥1 CNS demyelinating attacks, MOG-IgG seropositivity, and immunotherapy for ≥6 months. Patients were reviewed for CNS demyelinating attacks before and during long-term immunotherapy.ResultsSeventy patients were included. The median age at initial CNS demyelinating attack was 29 years (range 3–61 years; 33% <18 years), and 59% were female. The median annualized relapse rate (ARR) before treatment was 1.6. On maintenance immunotherapy, the proportion of patients with relapse was as follows: mycophenolate mofetil 74% (14 of 19; ARR 0.67), rituximab 61% (22 of 36; ARR 0.59), azathioprine 59% (13 of 22; ARR 0.2), and IV immunoglobulin (IVIG) 20% (2 of 10; ARR 0). The overall median ARR on these 4 treatments was 0.3. All 9 patients treated with multiple sclerosis (MS) disease-modifying agents had a breakthrough relapse on treatment (ARR 1.5).ConclusionThis large retrospective multicenter study of patients with MOGAD suggests that maintenance immunotherapy reduces recurrent CNS demyelinating attacks, with the lowest ARR being associated with maintenance IVIG therapy. Traditional MS disease-modifying agents appear to be ineffective. Prospective randomized controlled studies are required to validate these conclusions.

Acute flaccid myelitis (AFM) is a disabling, polio-like illness mainly affecting children. Outbreaks of AFM have occurred across multiple global regions since 2012, and the disease appears to be caused by non-polio enterovirus infection, posing a major public health challenge. The clinical presentation of flaccid and often profound muscle weakness (which can invoke respiratory failure and other critical complications) can mimic several other acute neurological illnesses. There is no single sensitive and specific test for AFM, and the diagnosis relies on identification of several important clinical, neuroimaging, and cerebrospinal fluid characteristics. Following the acute phase of AFM, patients typically have substantial residual disability and unique long-term rehabilitation needs. In this Review we describe the epidemiology, clinical features, course, and outcomes of AFM to help to guide diagnosis, management, and rehabilitation. Future research directions include further studies evaluating host and pathogen factors, including investigations into genetic, viral, and immunological features of affected patients, host-virus interactions, and investigations of targeted therapeutic approaches to improve the long-term outcomes in this population.

Objective To assess real‐world effectiveness of initial treatment with newer compared to injectable disease‐modifying therapies (DMTs) on disease activity in pediatric multiple sclerosis (MS) and clinically isolated syndrome (CIS). Methods This is a cohort study of children with MS/CIS followed at 12 clinics in the US Network of Pediatric MS Centers, who received initial therapy with newer (fingolimod, dimethyl fumarate, teriflunomide, natalizumab, rituximab, ocrelizumab) or injectable (interferon‐β, glatiramer acetate) DMTs. Propensity scores (PSs) were computed, including preidentified confounders. Relapse rate while on initial DMT was modeled with negative binomial regression, adjusted for PS‐quintile. Time to new/enlarging T2‐hyperintense and gadolinium‐enhancing lesions on brain magnetic resonance imaging were modeled with midpoint survival analyses, adjusted for PS‐quintile. Results A total of 741 children began therapy before 18 years, 197 with newer and 544 with injectable DMTs. Those started on newer DMTs were older (15.2 vs injectable 14.4 years, p = 0.001) and less likely to have a monofocal presentation. In PS‐quintile–adjusted analysis, those on newer DMTs had a lower relapse rate than those on injectables (rate ratio = 0.45, 95% confidence interval (CI) = 0.29–0.70, p < 0.001; rate difference = 0.27, 95% CI = 0.14–0.40, p = 0.004). One would need to treat with newer rather than injectable DMTs for 3.7 person‐years to prevent 1 relapse. Those started on newer DMTs had a lower rate of new/enlarging T2 (hazard ratio [HR] = 0.51, 95% CI = 0.36–0.72, p < 0.001) and gadolinium‐enhancing lesions (HR = 0.38, 95% CI = 0.23–0.63, p < 0.001) than those on injectables. Interpretation Initial treatment of pediatric MS/CIS with newer DMTs led to better disease activity control compared to injectables, supporting greater effectiveness of newer therapies. Long‐term safety data for newer DMTs are required. ANN NEUROL 2020 ANN NEUROL 2020;88:42–55