BACKGROUND AND PURPOSE:Demyelinating diseases constitute the most frequent cause of non-traumatic neurological disability in the pediatric population. Conventional MRI, while sensitive to focal white matter injury, lacks specificity to discern between edema, demyelination and axonal loss. This study aimed to employ advanced MRI biomarkers-specifically macromolecular tissue volume (MTV) and neurite orientation dispersion and density imaging (NODDI)-derived metrics-to assess myelin integrity (myelin volume fraction, MVF), axonal density (neurite density index, NDI), and the g-ratio in pediatric patients with multiple sclerosis (MS), neuromyelitis optica spectrum disorder (NMOSD), and myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD). MATERIALS AND METHODS:Thirty-nine pediatric patients (MS, n = 15; NMOSD, n = 6; MOGAD, n = 11), including 7 age-matched heathy controls, underwent 3 Tesla MRI as part of a cross-sectional study. Multi-echo gradient echo and multi-shell diffusion sequences were acquired to compute MTV and NODDI metrics. Lesional and normal-appearing white matter (NAWM) were segmented, and imaging metrics (MVF, NDI, and g-ratio) were compared across groups. Correlations between imaging biomarkers and clinical measures were also examined. RESULTS:MS demonstrated significantly higher lesional g-ratio than MOGAD (p = 0.02) and NMOSD (p = 0.02) and lower MVF than NMOSD (p = 0.006), indicating greater relative myelin loss. NAWM partitioning identified higher deep-NAWM ODI in MS patients than controls (p = 0.04). Within the MS cohort, 25ftW was associated with g-ratio, MVF, and NDI measures for both whole-brain and deep NAWM. CONCLUSION:Advanced MRI biomarkers provide a more nuanced characterization of microstructural alterations in pediatric demyelinating diseases. The distinct imaging profiles-highlighting greater demyelination in MS versus MOGAD and NMOSD-support the utility of these metrics for targeted clinical management and therapeutic stratification. Future longitudinal studies are warranted to further validate their role in monitoring disease progression and treatment response.

Importance:Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) lacks proven relapse-preventive therapies. While clinical trials are ongoing, safety data may be limited and approved drugs are costly. Studies of interleukin 6 receptor blocker (IL-6RB) in MOGAD are limited by small numbers and no comparative studies, contributing to low use. Objective:To evaluate the impact of IL-6RB therapy on relapse rates in MOGAD and compare relapse frequency with intravenous immunoglobulin (IVIG). Design, Setting, and Participants:This international, multicenter, retrospective cohort study (January 1, 2015, through December 31, 2025) included a historical IVIG-treated cohort of varying doses. The study took place across sites in North and South America (US, Canada, Mexico, Argentina, Brazil, Chile, Colombia, and Peru). Patients with MOGAD (n = 116, no excluded patients) who received at least 1 dose of an IL-6RB were included. These data were analyzed in January 2026. Exposures:Tocilizumab or satralizumab. Main Outcomes and Measures:Annualized relapse rate (ARR) during IL-6RB therapy, time to next relapse after treatment initiation, and adverse events. Outcomes were compared with the IVIG cohort using inverse probability of treatment weighting (IPTW) adjusted for age, sex, prior ARR, and concomitant therapies. Results:A total of 116 patients with MOGAD (89% relapsing) receiving IL-6RB (tocilizumab, 104 [90%] and satralizumab, 12 [10%]) were included; overall, 60.3% were female, 39.7% were male, and 18% were younger than 18 years. The median (IQR) IL-6RB treatment follow-up was 1.4 (0.7-2.5) years and 23 relapses occurred during 241.8 person-years of IL-6RB therapy. The ARR decreased from 0.64 (95% CI, 0.58-0.70) for relapsing MOGAD before IL-6RB to 0.09 (95% CI, 0.06-0.14) during IL-6RB treatment (incidence rate ratio, 0.08; 95% CI, 0.04-0.16). Adverse events occurred in 58 patients (50%), most commonly mild infections, although 10 (9%) had severe infections. In the IVIG cohort (n = 59), 30 relapses occurred over 133.8 person-years (ARR, 0.22; 95% CI, 0.15-0.32). After IPTW, IL-6RB was associated with a lower hazard ratio (HR) than the group who underwent IVIG therapy less than 1 g/kg every 4 weeks (HR, 4.5; 95% CI, 2.0-9.8), with no significant difference vs the group who underwent IVIG 1 g/kg or more every 4 weeks (HR, 2.0; 95% CI, 0.8-4.5). Conclusions and Relevance:In this multicenter observational cohort, IL-6RB use in MOGAD was associated with low relapse rates and a favorable safety profile, though severe infections occurred occasionally. Relapse rates were lower than the group who underwent IVIG less than 1 g/kg every 4 weeks but not significantly different from the group who underwent IVIG 1 g/kg or more every 4 weeks. This supports IL-6RB as a potential relapse-prevention therapy in MOGAD; the wide availability and relative affordability of tocilizumab may enable broad global use.

Background: Glial fibrillary acid protein (GFAP) astrocytopathy is an autoimmune central nervous system disorder that rarely affects children. We describe a case of GFAP astrocytopathy with associated rhabdomyolysis in a pediatric patient. Methods: We report a case report from a tertiary care university hospital. Results: An 11-year-old girl developed subacute progressive neurological symptoms, beginning with vision changes and later followed by gait instability and lower extremity weakness over 2 months. On the day of presentation, she experienced new-onset upper extremity weakness. Examination revealed severe weakness of all 4 limbs and areflexia. She also had hematuria, with markedly elevated creatine kinase level of 64,408 U/L. Magnetic resonance imaging showed T2 hyperintensity in the optic chiasm and tract, a longitudinally extensive cord lesion, and cauda equina enhancement. Cerebrospinal fluid analysis revealed pleocytosis, elevated protein, and GFAP antibodies detected by cell-based assay. An electromyogram/nerve conduction study suggested peripheral nervous system involvement. Treatment with intravenous methylprednisolone, plasmapheresis, intravenous immunoglobulin, and rituximab led to partial clinical improvement. Conclusion: This case highlights a rare presentation of GFAP astrocytopathy with subacute visual loss, severe weakness, areflexia, and rhabdomyolysis. Clinicians should consider GFAP astrocytopathy in pediatric patients presenting with combined central and peripheral nervous system involvement. (c) 2025 Elsevier Inc. All rights are reserved, including those for text and data mining, AI training, and similar technologies.

Importance:Bioenergetic failure has been proposed as a driver of amyotrophic lateral sclerosis (ALS). CNM-Au8 is a suspension of gold nanocrystals that catalyzes the conversion of nicotinamide adenine dinucleotide hydride into NAD+, resulting in an increase of cellular adenosine triphosphate production. Objective:To determine the effects of CNM-Au8 on ALS disease progression. Design, Setting, and Participants:CNM-Au8 was tested as a regimen of the HEALEY ALS Platform Trial, a phase 2/3, multicenter, randomized, double-blind platform trial. The study was conducted at 54 sites in the US from July 2020 to March 2022 (final follow-up, March 17, 2022). A total of 161 participants with ALS were randomized to receive CNM-Au8 (n = 120) or regimen-specific placebo (n = 41). Data from 123 concurrently randomized placebo participants in other regimens were combined for analyses. Interventions:Eligible participants were randomized in a 3:3:2 ratio to receive CNM-Au8 60 mg daily (n = 61), CNM-Au8 30 mg daily (n = 59), or matching placebo (n = 41) for 24 weeks. Main Outcomes and Measures:The primary efficacy outcome was change from baseline through week 24 in ALS disease severity measured by a bayesian shared parameter model of function (based on the Revised Amyotrophic Lateral Sclerosis Functional Rating Scale) and survival, which provided an estimate of the rate of disease progression measured by the disease rate ratio (DRR), with a DRR of less than 1 indicating treatment benefit. Secondary end points included a Combined Assessment of Function and Survival using a joint-rank test, rate of decline in slow vital capacity (percent predicted), and survival free of permanent assisted ventilation. Results:Among 161 participants who were randomized within the CNM-Au8 regimen (mean age, 58.4 years; 61 [37.9%] female), 145 (90%) completed the trial. In the primary analysis comparing the combined CNM-Au8 dosage groups vs the combined placebo groups, the primary end point (DRR, 0.97 [95% credible interval, 0.783-1.175]; posterior probability of DRR <1, 0.65) and the 3 secondary end points suggested no benefit or harm of CNM-Au8. In the active (n = 120) vs placebo (n = 163) groups, the most common adverse events were diarrhea (23 [19%] vs 12 [7%]), nausea (17 [14.2%] vs 14 [8.6%]), fatigue (12 [10.8%] vs 30 [18.4%]), and muscular weakness (24 [20%] vs 45 [27.6%]). Conclusions and Relevance:No benefit of CNM-Au8 on ALS disease progression was observed at 24 weeks. Trial Registration:ClinicalTrials.gov Identifiers: NCT04297683, NCT04414345.

OBJECTIVES:Progression independent of relapse activity (PIRA) is a major contributor to long-term disability accumulation in multiple sclerosis (MS). This study aimed to explore the assessment of PIRA in clinical practice from the perspectives of people living with MS (pwMS) and healthcare providers (HCPs). METHODS:Cross-sectional surveys were conducted among 310 pwMS and 360 HCPs involved in MS care across seven countries in North America and Europe. RESULTS:HCPs proved to be more motor-focused, primarily through neurological examination and EDSS (75 %), whereas pwMS reported fatigue as the domain most affected (67 %), which was the least assessed domain by HCPs (31 %). 54-61 % of pwMS indicated that the thoroughness, average time spent, and frequency of PIRA assessment had remained the same since diagnosis. As reported by HCPs, roughly 40 % of PIRA assessment remained the same in pwMS with even moderate-severe disability, likely due to time constraints, considered the most limiting factor to measuring PIRA, as well as the lack of a comprehensive, standardized approach and sensitive tools to measure disability as reported by HCPs accurately. CONCLUSION:MS care necessitates a standardized and time-sensitive approach for assessing disability in the absence of relapse, to optimize care and enhance routine disability assessment and monitoring.

B-cell depletion with CD20-targeted agents is commonly used for treatment of multiple sclerosis (MS), other autoimmune diseases, and certain hematologic malignancies. Initial apparent success with rituximab in MS and neuromyelitis optica spurred development of the anti-CD20 monoclonal antibody (mAb) therapies ocrelizumab, ofatumumab, and ublituximab as well as the anti-CD19 mAb inebilizumab. While each are effective at targeting and depleting B cells, structural differences translate into different mechanisms of action affecting maintenance of B-cell depletion and safety and tolerability. Although the anti-CD20 mAbs differ in degree of human versus mouse sequences as well as target CD20 epitope, these properties do not appear to substantially affect activity or tolerability. In contrast, an antibody-dependent cell-mediated cytotoxicity (ADCC) versus a complement-dependent cytotoxicity mechanism of action as well as subcutaneous versus intravenous administration may provide improved tolerability. Glycoengineering of the mAbs ublituximab and inebilizumab enhances ADCC and can overcome the reduced responses to mAb-mediated B-cell depletion associated with certain genetic polymorphisms. Other strategies for therapeutic targeting of CD20, including brain shuttle antibodies (e.g., RO7121932), bispecific antibodies, chimeric antigen receptor T-cell therapies, and antibody–drug conjugates, are in active clinical development and may be future treatment approaches in MS and other B-cell-mediated autoimmune diseases.

Mutations in PIK3R1, a regulatory subunit of Class I PI3K, are implicated in immune disorders and neurological conditions. We identified a novel heterozygous pathogenic frameshift mutation (c.1710dup) in PIK3R1 in a patient with common variable immunodeficiency who developed slowly progressive Amyotrophic Lateral Sclerosis. Induced pluripotent stem cells (iPSCs) and iPSC-derived motor neurons (iMNs) demonstrated that this mutation resulted in PIK3R1 haploinsufficiency, with downstream activation of AKT, disruption of neuronal electrical function and increased apoptosis in iPSC-derived motor neurons. Single-cell RNA sequencing (scRNA-seq) and pathway analysis of differentially expressed genes showed apoptosis pathways were upregulated in neuronal clusters from iMNs harboring the PIK3R1c.1710 dup mutation. Mutated iPSC-derived brain organoids were smaller than matched controls. scRNA-seq of brain organoids showed more active apoptosis in neuronal clusters of patient-derived brain organoids. These findings identify a critical and novel role for PIK3R1 haploinsufficiency in neuronal function and survival.

Importance:Biomarkers distinguishing nonrelapsing progressive disease biology from relapsing biology in multiple sclerosis (MS) are lacking. Cerebrospinal fluid (CSF) is an accessible fluid that most closely reflects central nervous system biology. Objective:To identify CSF biological measures associated with progressive MS pathobiology. Design, Setting, and Participants:This cohort study assessed data from 2 prospective MS cohorts: a test cohort provided serial CSF, clinical, and imaging assessments in a multicenter study of patients with relapsing MS (RMS) or primary progressive MS (PPMS) who were initiating anti-CD20 treatment (recruitment: 2016-2018; analysis: 2020-2023). A single-site confirmation cohort was used to assess CSF at baseline and long-term (>10 year) clinical follow-up (analysis: 2022-2023). Exposures:Test-cohort participants initiated standard-of-care ocrelizumab treatment. Confirmation-cohort participants were untreated or received standard-of-care disease-modifying MS therapies. Main Outcomes and Measures:Twenty-five CSF markers, including neurofilament light chain, neurofilament heavy chain, and glial fibrillary acid protein (GFAP); 24-week confirmed disability progression (CDP24); and brain magnetic resonance imaging measures reflecting focal injury, tissue loss, and progressive biology (slowly expanding lesions [SELs]). Results:The test cohort (n = 131) included 100 patients with RMS (mean [SD] age, 36.6 [10.4] years; 68 [68%] female and 32 [32%] male; Expanded Disability Status Scale [EDSS] score, 0-5.5), and 31 patients with PPMS (mean [SD] age, 44.9 [7.4] years; 15 [48%] female and 16 [52%] male; EDSS score, 3.0-6.5). The confirmation cohort (n = 68) included 41 patients with RMS and 27 with PPMS enrolled at diagnosis (age, 40 years [range, 20-61 years]; 47 [69%] female and 21 [31%] male). In the test cohort, GFAP was correlated with SEL count (r = 0.33), greater proportion of T2 lesion volume from SELs (r = 0.24), and lower T1-weighted intensity within SELs (r = -0.33) but not with acute inflammatory measures. Neurofilament heavy chain was correlated with SEL count (r = 0.25) and lower T1-weighted intensity within SELs (r = -0.28). Immune markers correlated with measures of acute inflammation and, unlike GFAP, were impacted by anti-CD20. In the confirmation cohort, higher baseline CSF GFAP levels were associated with long-term CDP24 (hazard ratio, 2.1; 95% CI, 1.3-3.4; P = .002). Conclusions and Relevance:In this study, activated glial markers (in particular GFAP) and neurofilament heavy chain were associated specifically with nonrelapsing progressive disease outcomes (independent of acute inflammatory activity). Elevated CSF GFAP was associated with long-term MS disease progression.

Background:Myelin oligodendrocyte glycoprotein antibody associated disease (MOGAD) is a relatively new disease entity in the field of demyelinating disorders. Its first diagnostic criteria have recently been published. Objectives:We evaluated the positive predictive value (PPV) for MOG-IgG testing and report the clinical and radiologic features with respect to the recently published criteria. Methods:A retrospective study was conducted at three centers in Dallas, Texas. Patients with positive MOG-IgG testing on cell-based assays at any time were included. Positive cases were reviewed by at least two neuroimmunologists for fulfillment of the criteria. Results:We included 235 patients. The PPV of seropositivity at any time was 78.3% overall, 52.6% for low titer, and 90.1% for high titer. Children had a higher PPV than adults (93.9% versus 67.2%). Positive predictive value was 6.3% in those without a core clinical demyelinating attack. Children more often have the typical imaging features of MOGAD in optic neuritis than adults. Conclusions:We report a PPV of 78.3% for MOG-IgG testing using the 2023 MOGAD diagnostic criteria. Children had higher PPV and frequency of supporting imaging features. Careful consideration is necessary when assigning patients with no core demyelinating event and low titers a MOGAD diagnosis.

BACKGROUND:This study evaluated the clinical characteristics of neuronal ceroid lipofuscinosis type 7 or CLN7 disease spectrum to characterize the clinical, electrophysiologic and neuroimaging phenotypes. METHODS:We performed a single-center cross sectional data collection along with retrospective medical chart review in patients with a genetic diagnosis of CLN7. This study received ethical approval by the University of Texas Southwestern Medical Center Institutional Review Board. A total of 8 patients were included between the ages of 4 to 6 years. All patients had a genetic diagnosis of CLN7 with homozygous or compound heterozygous mutations in the MFSD8 gene. The information collected includes patient demographics, developmental history, neurological events including seizures and neurodevelopmental regression along with further evaluation of brain magnetic resonance imaging and electrophysiological findings. The clinical phenotype is described through cross sectional and retrospective data collection and standardized tools assessing quality of life and functional skills. RESULTS:Our findings in this cohort of CLN7 patients indicated that development is initially normal with onset of clinical symptoms as early as two years of age. Language problems were noted prior to or at the onset of seizures in all cases. Gait problems were noted prior to seizure onset in 3 of 8 patients, and at or within 6 months after the onset of seizures in 5 of 8 patients. All patients followed a progressive course of language, motor, and neurocognitive deterioration. Congruent with the medical history, our patients had significantly low scores on adaptive abilities. Natural history data such as this can be used to support future clinical trial designs. CONCLUSIONS:This study provides a comprehensive description of CLN7 disease, highlighting clinical data alongside standardized neuropsychological assessments, neuroimaging, and electrophysiologic data. It emphasizes the value of importance of standardized tools for understanding disease phenotype and their potential use as endpoints in future clinical trials. The findings established can provide a baseline for developing future prospective natural history studies and potential therapeutic clinical trials.

Abstract Background Pediatric acute transverse myelitis (ATM) accounts for 20–30% of children presenting with a first acquired demyelinating syndrome (ADS) and may be the first clinical presentation of a relapsing ADS such as multiple sclerosis (MS). B cells have been strongly implicated in the pathogenesis of adult MS. However, little is known about B cells in pediatric MS, and even less so in pediatric ATM. Our lab previously showed that plasmablasts (PB), the earliest B cell subtype producing antibody, are expanded in adult ATM, and that these PBs produce self-reactive antibodies that target neurons. The goal of this study was to examine PB frequency and phenotype, immunoglobulin selection, and B cell receptor reactivity in pediatric patients presenting with ATM to gain insight to B cell involvement in disease. Methods We compared the PB frequency and phenotype of 5 pediatric ATM patients and 10 pediatric healthy controls (HC) and compared them to previously reported adult ATM patients using cytometric data. We purified bulk IgG from the plasma samples and cloned 20 recombinant human antibodies (rhAbs) from individual PBs isolated from the blood. Plasma-derived IgG and rhAb autoreactivity was measured by mean fluorescence intensity (MFI) in neurons and astrocytes of murine brain or spinal cord and primary human astrocytes. We determined the potential impact of these rhAbs on astrocyte health by measuring stress and apoptotic response. Results We found that pediatric ATM patients had a reduced frequency of peripheral blood PB. Serum IgG autoreactivity to neurons in EAE spinal cord was similar in the pediatric ATM patients and HC. However, serum IgG autoreactivity to astrocytes in EAE spinal cord was reduced in pediatric ATM patients compared to pediatric HC. Astrocyte-binding strength of rhAbs cloned from PBs was dependent on somatic hypermutation accumulation in the pediatric ATM cohort, but not HC. A similar observation in predilection for astrocyte binding over neuron binding of individual antibodies cloned from PBs was made in EAE brain tissue. Finally, exposure of human primary astrocytes to these astrocyte-binding antibodies increased astrocytic stress but did not lead to apoptosis. Conclusions Discordance in humoral immune responses to astrocytes may distinguish pediatric ATM from HC.