Dimethyl Fumarate Delays Multiple Sclerosis in Radiologically Isolated Syndrome.

OBJECTIVE: The radiologically isolated syndrome (RIS) represents the earliest detectable pre-clinical phase of multiple sclerosis (MS). This study evaluated the impact of therapeutic intervention in preventing first symptom manifestation at this stage in the disease spectrum. METHODS: We conducted a multi-center, randomized, double-blinded, placebo-controlled study involving people with RIS. Individuals without clinical symptoms typical of MS but with incidental brain MRI anomalies consistent with central nervous system (CNS) demyelination were included. Within 12 MS centers in the United States, participants were randomly assigned 1:1 to oral dimethyl fumarate (DMF) 240 mg twice daily or placebo. The primary endpoint was the time to onset of clinical symptoms attributable to a CNS demyelinating event within a follow-up period of 96 weeks. An intention-to-treat analysis was applied to all participating individuals in the primary and safety investigations. The study is registered at ClinicalTrials.gov, NCT02739542 (ARISE). RESULTS: Participants from 12 centers were recruited from March 9, 2016, to October 31, 2019, with 44 people randomized to dimethyl fumarate and 43 to placebo. Following DMF treatment, the risk of a first clinical demyelinating event during the 96-week study period was highly reduced in the unadjusted Cox proportional-hazards regression model (hazard ratio [HR] = 0.18, 95% confidence interval [CI] = 0.05-0.63, p = 0.007). More moderate adverse reactions were present in the DMF (34 [32%]) than placebo groups (19 [21%]) but severe events were similar (DMF, 3 [5%]; placebo, 4 [9%]). INTERPRETATION: This is the first randomized clinical trial demonstrating the benefit of a disease-modifying therapy in preventing a first acute clinical event in people with RIS. ANN NEUROL 2023;93:604-614.

Challenges in the Clinical Recognition of Acute Flaccid Myelitis and its Implications.

OBJECTIVES: To explore the challenges in diagnosing acute flaccid myelitis (AFM) and evaluate clinical features and treatment paradigms associated with under recognition. STUDY DESIGN: This was a retrospective multicenter study of pediatric patients (≤18 years) who were diagnosed with AFM from 2014 to 2018 using the Centers for Disease Control and Prevention's case definition. RESULTS: In 72% of the cases (126 of 175), AFM was not considered in the initial differential diagnosis (n = 108; 61.7%) and/or the patient was not referred for acute care (n = 90; 51.4%) at the initial clinical encounter, and this did not improve over time. Although many features of the presentation were similar in those initially diagnosed with AFM and those who were not; preceding illness, constipation, and reflexes differed significantly between the 2 groups. Patients with a non-AFM initial diagnosis more often required ventilatory support (26.2% vs 12.2%; OR, 0.4; 95% CI, 0.2-1.0; P = .05). These patients received immunomodulatory treatment later (3 days vs 2 days after neurologic symptom onset; 95% CI, -2 to 0; P = .05), particularly intravenous immunoglobulin (5 days vs 2 days; 95% CI, -4 to -2; P < .001). CONCLUSIONS: Delayed recognition of AFM is concerning because of the risk for respiratory decompensation and need for intensive care monitoring. A non-AFM initial diagnosis was associated with delayed treatment that could have a clinical impact, particularly as new treatment options emerge.

Severe Pediatric Neurological Manifestations With SARS-CoV-2 or MIS-C Hospitalization and New Morbidity.

Importance: Neurological manifestations during acute SARS-CoV-2-related multisystem inflammatory syndrome in children (MIS-C) are common in hospitalized patients younger than 18 years and may increase risk of new neurocognitive or functional morbidity. Objective: To assess the association of severe neurological manifestations during a SARS-CoV-2-related hospital admission with new neurocognitive or functional morbidities at discharge. Design, Setting, and Participants: This prospective cohort study from 46 centers in 10 countries included patients younger than 18 years who were hospitalized for acute SARS-CoV-2 or MIS-C between January 2, 2020, and July 31, 2021. Exposure: Severe neurological manifestations, which included acute encephalopathy, seizures or status epilepticus, meningitis or encephalitis, sympathetic storming or dysautonomia, cardiac arrest, coma, delirium, and stroke. Main Outcomes and Measures: The primary outcome was new neurocognitive (based on the Pediatric Cerebral Performance Category scale) and/or functional (based on the Functional Status Scale) morbidity at hospital discharge. Multivariable logistic regression analyses were performed to examine the association of severe neurological manifestations with new morbidity in each SARS-CoV-2-related condition. Results: Overall, 3568 patients younger than 18 years (median age, 8 years [IQR, 1-14 years]; 54.3% male) were included in this study. Most (2980 [83.5%]) had acute SARS-CoV-2; the remainder (588 [16.5%]) had MIS-C. Among the patients with acute SARS-CoV-2, 536 (18.0%) had a severe neurological manifestation during hospitalization, as did 146 patients with MIS-C (24.8%). Among survivors with acute SARS-CoV-2, those with severe neurological manifestations were more likely to have new neurocognitive or functional morbidity at hospital discharge compared with those without severe neurological manifestations (27.7% [n = 142] vs 14.6% [n = 356]; P < .001). For survivors with MIS-C, 28.0% (n = 39) with severe neurological manifestations had new neurocognitive and/or functional morbidity at hospital discharge compared with 15.5% (n = 68) of those without severe neurological manifestations (P = .002). When adjusting for risk factors in those with severe neurological manifestations, both patients with acute SARS-CoV-2 (odds ratio, 1.85 [95% CI, 1.27-2.70]; P = .001) and those with MIS-C (odds ratio, 2.18 [95% CI, 1.22-3.89]; P = .009) had higher odds of having new neurocognitive and/or functional morbidity at hospital discharge. Conclusions and Relevance: The results of this study suggest that children and adolescents with acute SARS-CoV-2 or MIS-C and severe neurological manifestations may be at high risk for long-term impairment and may benefit from screening and early intervention to assist recovery.

Efficacy of Dimethyl Fumarate in Young Adults with Relapsing-Remitting Multiple Sclerosis: Analysis of the DEFINE, CONFIRM, and ENDORSE Studies.

INTRODUCTION: Dimethyl fumarate (DMF) showed favorable benefit-risk in patients with relapsing-remitting multiple sclerosis (MS) in phase 3 DEFINE and CONFIRM trials and in the ENDORSE extension study. Disease activity can differ in younger patients with MS compared with the overall population. METHODS: Randomized patients received DMF 240 mg twice daily or placebo (PBO; years 0-2 DEFINE/CONFIRM), then DMF (years 3-10; continuous DMF/DMF or PBO/DMF; ENDORSE); maximum follow-up (combined studies) was 13 years. This integrated post hoc analysis evaluated safety and efficacy of DMF in a subgroup of young adults aged 18-29 years. RESULTS: Of 1736 patients enrolled in ENDORSE, 125 were young adults, 86 treated continuously with DMF (DMF/DMF) and 39 received delayed DMF (PBO/DMF) in DEFINE/CONFIRM. Most (n = 116 [93%]) young adults completed DMF treatment in DEFINE/CONFIRM. Median (range) follow-up time in ENDORSE was 6.5 (2.0-10.0) years. Young adults entering ENDORSE who had been treated with DMF in DEFINE/CONFIRM had a model-based Annualized Relapse Rate (ARR; 95% CI) of 0.24 (0.16-0.35) vs. 0.56 (0.35-0.88) in PBO patients. ARR remained low in ENDORSE: 0.07 (0.01-0.47) at years 9-10 (DMF/DMF group). At year 10 of ENDORSE, EDSS scores were low in young adults: DMF/DMF, 1.9 (1.4); PBO/DMF, 2.4 (1.6). At ~ 7 years, the proportion of young adults with no confirmed disability progresion was 81% for DMF/DMF and 72% for PBO/DMF. Patient-reported outcomes (PROs) (SF-36 and EQ-5D) generally remained stable during ENDORSE. The most common adverse events (AEs) in young adults during ENDORSE were MS relapse (n = 53 [42%]). Most AEs were mild (n = 20 [23.3%], n = 7 [17.9%]) to moderate (n = 45 [52.3%], n = 23 [59.0%]) in the DMF/DMF and PBO/DMF groups, respectively. The most common serious AE (SAE) was MS relapse (n = 19 [15%]). CONCLUSION: The data support a favorable benefit-risk profile of DMF in young adults, as evidenced by well-characterized safety, sustained efficacy, and stable PROs. CLINICAL TRIAL INFORMATION: Clinical trials.gov, DEFINE (NCT00420212), CONFIRM (NCT00451451), and ENDORSE (NCT00835770).

Approach to New-Onset Psychosis in Pediatrics: A Review of Current Practice and an Interdisciplinary Consensus-Driven Clinical Pathway at a Single-Center Institution.

New-onset psychosis in the pediatric population poses many diagnostic challenges. Given the diversity of underlying causes, which fall under the purview of multiple medical specialties, a timely, targeted, yet thorough workup requires a systematic and coordinated approach. A committee of expert pediatric physicians from the divisions of emergency medicine, psychiatry, neurology, hospitalist medicine, and radiology convened to create and implement a novel clinical pathway and approach to the pediatric patient presenting with new-onset psychosis. Here we provide background and review the evidence supporting the investigations recommended in our pathway to screen for a comprehensive range of etiologies of pediatric psychosis.

Distinct Th17 effector cytokines differentially promote microglial and blood-brain barrier inflammatory responses during post-infectious encephalitis.

Group A Streptococcus (GAS) infections can cause neuropsychiatric sequelae in children due to post-infectious encephalitis. Multiple GAS infections induce migration of Th17 lymphocytes from the nose into the brain, which are critical for microglial activation, blood-brain barrier (BBB) and neural circuit impairment in a mouse disease model. How endothelial cells (ECs) and microglia respond to GAS infections, and which Th17-derived cytokines are essential for these responses are unknown. Using single-cell RNA sequencing and spatial transcriptomics, we found that ECs downregulate BBB genes and microglia upregulate interferon-response, chemokine and antigen-presentation genes after GAS infections. Several microglial-derived chemokines were elevated in patient sera. Administration of a neutralizing antibody against interleukin-17A (IL-17A), but not ablation of granulocyte-macrophage colony-stimulating factor (GM-CSF) in T cells, partially rescued BBB dysfunction and microglial expression of chemokine genes. Thus, IL-17A is critical for neuropsychiatric sequelae of GAS infections and may be targeted to treat these disorders.

Prevalence and Risk Factors of Neurologic Manifestations in Hospitalized Children Diagnosed with Acute SARS-CoV-2 or MIS-C.

BACKGROUND: Our objective was to characterize the frequency, early impact, and risk factors for neurological manifestations in hospitalized children with acute severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection or multisystem inflammatory syndrome in children (MIS-C). METHODS: Multicenter, cross-sectional study of neurological manifestations in children aged <18 years hospitalized with positive SARS-CoV-2 test or clinical diagnosis of a SARS-CoV-2-related condition between January 2020 and April 2021. Multivariable logistic regression to identify risk factors for neurological manifestations was performed. RESULTS: Of 1493 children, 1278 (86%) were diagnosed with acute SARS-CoV-2 and 215 (14%) with MIS-C. Overall, 44% of the cohort (40% acute SARS-CoV-2 and 66% MIS-C) had at least one neurological manifestation. The most common neurological findings in children with acute SARS-CoV-2 and MIS-C diagnosis were headache (16% and 47%) and acute encephalopathy (15% and 22%), both P < 0.05. Children with neurological manifestations were more likely to require intensive care unit (ICU) care (51% vs 22%), P < 0.001. In multivariable logistic regression, children with neurological manifestations were older (odds ratio [OR] 1.1 and 95% confidence interval [CI] 1.07 to 1.13) and more likely to have MIS-C versus acute SARS-CoV-2 (OR 2.16, 95% CI 1.45 to 3.24), pre-existing neurological and metabolic conditions (OR 3.48, 95% CI 2.37 to 5.15; and OR 1.65, 95% CI 1.04 to 2.66, respectively), and pharyngeal (OR 1.74, 95% CI 1.16 to 2.64) or abdominal pain (OR 1.43, 95% CI 1.03 to 2.00); all P < 0.05. CONCLUSIONS: In this multicenter study, 44% of children hospitalized with SARS-CoV-2-related conditions experienced neurological manifestations, which were associated with ICU admission and pre-existing neurological condition. Posthospital assessment for, and support of, functional impairment and neuroprotective strategies are vitally needed.

Critical Analysis of a Challenging Case of Post-Infectious N-Methyl-D-Aspartate Receptor Encephalitis.

Infections are increasingly recognized as a common trigger of autoimmune disease, including autoimmune encephalitis. A significant association is particularly shown between HSV-1 encephalitis (HSVE) and a post-infectious autoimmune encephalitis mediated by neuronal autoantibodies, most notably anti-N-methyl-D-aspartate receptor (NMDAR) antibodies. The clinical significance of these and other novel post-infectious autoantibodies has led to new diagnostic and treatment challenges for clinicians. Here we present a case of a 19-year-old female with premorbid psychiatric disease and neuropsychiatric sequelae from HSVE who presented over a year after her initial HSVE with behavioral changes and positive anti-NMDAR antibodies. The clinical challenges encountered during this case are explored in detail based on a review of the literature. Research is needed to help guide management in these complex clinical situations.

Evaluation of ocrelizumab in older progressive multiple sclerosis patients.

BACKGROUND: Seminal trials evaluating anti-CD20 therapy in progressive MS primarily found benefit in younger, less-disabled patients with more inflammatory disease activity. The risks and benefits of ocrelizumab use in older patients with progressive froms of MS are not known. METHODS: Retrospective chart review was performed for patients older than 55 with primary or secondary progressive MS at the time of ocrelizumab initiation. Clinical endpoints from 2 years prior to anti-CD20 therapy served as a within-subject control. RESULTS: Data was reviewed for 56 patients older than the age of 55 at the time of ocrelizumab initiation. Of 37 patients with 2-years of follow up on ocrelizumab, 40%(n=15) experienced confirmed disability progression (CDP) while 60% (n=22) remained stable or improved. 24 patients had data available for the within-subject control; for these patients, median age was 67, baseline EDSS 6.3, and disease duration 20.5 years. Prior to anti-CD20 therapy, 58% (n=14) of patients remained stable and 42% (n=10) experienced CDP. After ocrelizumab initiation, 71% (n=17) remained stable and 29% (n=7) experienced CDP. There was no difference between CDP (p=0.54) or change in EDSS (p=0.09) between time periods. Ocrelizumab was well tolerated and no difference in infection rate was seen using the within-subject control. CONCLUSIONS: We found no difference in clinical endpoints for patients on ocrelizumab compared to prior to anti-CD20 therapy; however, we could not exclude a modest effect given our sample size. Larger trials are needed to evaluate ocrelizumab use in this understudied MS subpopulation.

Potential Neurologic Manifestations of COVID-19.

PURPOSE OF REVIEW: Neurologic complications are increasingly recognized in the coronavirus disease 2019 (COVID-19) pandemic. COVID-19 is caused by the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This coronavirus is related to severe acute respiratory syndrome coronavirus (SARS-CoV) and other human coronavirus-related illnesses that are associated with neurologic symptoms. These symptoms raise the question of a neuroinvasive potential of SARS-CoV-2. RECENT FINDINGS: Potential neurologic symptoms and syndromes of SARS-CoV-2 include headache, fatigue, dizziness, anosmia, ageusia, anorexia, myalgias, meningoencephalitis, hemorrhage, altered consciousness, Guillain-Barré syndrome, syncope, seizure, and stroke. In addition, we discuss neurologic effects of other coronaviruses, special considerations for management of neurologic patients, and possible long-term neurologic and public health sequelae. SUMMARY: As SARS-CoV-2 is projected to infect a large part of the world's population, understanding the potential neurologic implications of COVID-19 will help neurologists and others recognize and intervene in neurologic morbidity during and after the pandemic of 2020.

Neurological issues in children with COVID-19.

Coronavirus disease 2019 (COVID-19) usually leads to a mild infectious disease course in children, but serious complications may occur in conjunction with both acute infection and associated phenomena such as the multisystem inflammatory syndrome in children (MIS-C). Neurological symptoms, which have been predominantly reported in adults, range from mild headache to seizure, peripheral neuropathy, stroke, demyelinating disorders, and encephalopathy. Similar to respiratory and cardiac manifestations of COVID-19, neurological complications present differently based on age and underlying comorbidities. This review provides a concise overview of the neurological conditions seen in the context of COVID-19, as well as potential mechanisms and long-term implications of COVID-19 in the pediatric population from literature reviews and primary data collected at NewYork-Presbyterian Morgan Stanley Children's Hospital.

Myelin oligodendrocyte glycoprotein (MOG) antibody-mediated disease: The difficulty of predicting relapses.

BACKGROUND: While many patients with myelin oligodendrocyte glycoprotein antibody-mediated disease (MOG-AD) will have a monophasic course, 30-80% of patients will relapse after the initial attack. It is not known which factors predict relapse. Here we describe our clinical experience with MOG-AD and evaluate for factors that correlate with relapsing disease. METHODS: This was a retrospective, multi-institutional study of 54 patients with MOG-AD, including 17 children and 37 adults. Mann-Whitney U and Fischer's Exact tests were used for comparisons and logistic regression for correlations. RESULTS: Incident attack phenotype included acute disseminated encephalomyelitis (15%), unilateral optic neuritis (ON; 39%), bilateral ON (24%), transverse myelitis (TM; 11%) and ON with TM (11%). Pediatric patients were more likely than adults to present with ADEM (p = .009) and less likely to present with unilateral ON (p = .04). 31 patients (57%) had a relapsing disease course, with time to first relapse of 8.2 months and median annualized relapse rate of 0.97 months. In 40% of patients (n = 22) the first relapse occurred following the withdrawal of treatment for the incident attack. 5 patients converted to seronegative at follow up, 2 of whom later relapsed. Logistic regression revealed no significant relationship between age, gender, race, presentation phenotype, antibody titer, or cerebrospinal fluid results with risk of relapse. For patients who started disease modifying therapy (DMT) prior to the first relapse (n = 11), 64% remained monophasic. 50% (n = 15) of patients on DMT continued to have disease activity, requiring treatment adjustment. CONCLUSIONS: It is difficult to predict which patients with MOG-AD will relapse. Research is needed to determine the optimal timing and choice of treatment.

Manifestations and impact of the COVID-19 pandemic in neuroinflammatory diseases.

OBJECTIVE: To report initial results of a planned multicenter year-long prospective study examining the risk and impact of COVID-19 among persons with neuroinflammatory disorders (NID), particularly multiple sclerosis (MS). METHODS: In April 2020, we deployed online questionnaires to individuals in their home environment to assess the prevalence and potential risk factors of suspected COVID-19 in persons with NID (PwNID) and change in their neurological care. RESULTS: Our cohort included 1115 participants (630 NID, 98% MS; 485 reference) as of 30 April 2020. 202 (18%) participants, residing in areas with high COVID-19 case prevalence, met the April 2020 CDC symptom criteria for suspected COVID-19, but only 4% of all participants received testing given testing shortages. Among all participants, those with suspected COVID-19 were younger, more racially diverse, and reported more depression and liver disease. PwNID had the same rate of suspected COVID-19 as the reference group. Early changes in disease management included telemedicine visits in 21% and treatment changes in 9% of PwNID. After adjusting for potential confounders, increasing neurological disability was associated with a greater likelihood of suspected COVID-19 (ORadj  = 1.45, 1.17-1.84). INTERPRETATIONS: Our study of real-time, patient-reported experience during the COVID-19 pandemic complements physician-reported MS case registries which capture an excess of severe cases. Overall, PwNID seem to have a risk of suspected COVID-19 similar to the reference population.

Neuroimmunologic disorders in pregnancy.

Pregnancy influences the course of neuroimmunologic conditions, which include multiple sclerosis (MS), neuromyelitis optica spectrum disorder, and autoimmune encephalitis. The outcomes differ significantly for each disorder, reflecting the impact of hormonal changes, T-cell subsets, and placental factors on disease pathogenesis. In recent years, numerous data have emerged regarding MS activity throughout pregnancy and postpartum. Historically, the misconception that pregnancy worsens MS outcomes led patients to abstain from childbearing. Now, more women with these disorders, empowered by up-to-date information and better baseline disease control, are choosing to conceive. Nevertheless, the management of MS and related disorders in the pregnancy and postpartum period is complicated and requires a nuanced approach. Since standardized treatment guidelines around pregnancy are currently lacking, neurologists, together with obstetricians, must engage patients in a shared decision-making process that weighs the benefits to the mother and risks to the fetus. This chapter outlines the pathophysiology of neuroimmunologic disorders during pregnancy and postpartum, the impact of these diseases on childbearing, including fertility, pregnancy, delivery, and peurperium, as well as existing recommendations for treatment.

Pediatric Inflammatory and Autoimmune Neurologic Disorders at a Tertiary Medical Center.

OBJECTIVES: To describe the spectrum of pediatric inflammatory neurologic diseases and compare the sensitivity of ancillary testing for these diagnoses. METHODS: We analyzed clinical features and outcomes of 98 children with an immune-mediated central nervous system disorder. We compared sensitivities of each diagnostic modality. RESULTS: We identified the following diagnoses: acute cerebellar ataxia (n = 14; 14.3%), acute demyelinating encephalomyelitis (n = 13; 13.3%), multiple sclerosis (MS) (n = 18; 18.4%), anti-N-methyl-d-aspartate receptor encephalitis (anti-NMDAR encephalitis) (n = 15; 15.3%), encephalitis not otherwise specified (n = 12; 12.2%), and "Other" (n = 26; 26.5%). "Other" included acute transverse myelitis, neuromyelitis optica, central nervous system lupus, primary central nervous system vasculitis, Rasmussen encephalitis, opsoclonus myoclonus ataxia syndrome, and clinically isolated syndrome. The mean age of onset of all diagnoses was 7.9 ± 5.5 years. The diagnostic sensitivity of magnetic resonance imaging (MRI) for acute demyelinating encephalomyelitis and multiple sclerosis was 92.3% and 94.4%, respectively. Cerebrospinal fluid was sensitive for multiple sclerosis in 92.3%, where 75% of patients had cerebrospinal fluid oligoclonal bands. Electroencephalogram (EEG) coupled with cerebrospinal fluid studies was highly sensitive for anti-NMDAR encephalitis (100%). EEG was sensitive for acute demyelinating encephalomyelitis and encephalitis not otherwise specified (77.8% and 80%). No diagnostic studies were sensitive for acute cerebellar ataxia. Seventy-three percent of patients with multiple sclerosis had residual deficits. Thirty-six percent of anti-NMDAR encephalitis patients were nonverbal and wheel-chair bound. CONCLUSIONS: We found that MRI is useful for detecting multiple sclerosis and acute demyelinating encephalomyelitis, cerebrospinal fluid is helpful in diagnosing multiple sclerosis and anti-NMDAR encephalitis, and EEG is often abnormal in suspected anti-NMDAR encephalitis, acute demyelinating encephalomyelitis, and encephalitis not otherwise specified. Neurologic outcome at follow-up was unfavorable in patients with multiple sclerosis and anti-NMDAR encephalitis.

Association of social network structure and physical function in patients with multiple sclerosis.

OBJECTIVE: To test the association between physical function and the social environment in multiple sclerosis (MS), we quantified personal social networks. METHODS: In this cross-sectional study, we analyzed data from 2 academic MS centers, with center 1 serving as a discovery group and center 2 as the extension group. We performed a meta-analysis of the centers to extend the analysis. We used responses from a questionnaire to map the structure and health habits of participants' social networks as well as the NIH Patient-Reported Outcomes Measurement Information System (PROMIS) physical function scale (0-100, mean 50 for US general population) as the primary outcome. We applied multivariable models to test the association between network metrics and physical function. RESULTS: The discovery cohort included 263 patients with MS: 81% were women, 96% non-Hispanic European, 78% had relapsing MS, average age was 50 (12.4) years, and mean disease duration was 17 (12.3) years. The extension group included 163 patients, who were younger, more racially diverse, and less physically disabled, and had shorter disease duration. In the meta-analysis, higher network constraint, a measure of tightly bound networks, was associated with worse physical function (ß = -0.163 ± 0.047, p < 0.001), while larger network effective size, a measure of clustered groups in the network, correlated with better physical function (ß = 0.134 ± 0.046, p = 0.003). CONCLUSIONS: Our study highlights personal networks as an important environmental factor associated with physical function in MS. Patients with close-knit networks had worse function than those with more open networks. Longitudinal studies are warranted to evaluate a causal relationship between network structure and physical impairment.