Life-Threatening MOG Antibody-Associated Hemorrhagic ADEM With Elevated CSF IL-6.

Acute disseminated encephalomyelitis (ADEM) is one characteristic manifestation of myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD). A previously healthy man presented with retro-orbital headache and urinary retention 14 days after Tdap vaccination. Brain and spine MRI suggested a CNS demyelinating process. Despite treatment with IV steroids, he deteriorated, manifesting hemiparesis and later impaired consciousness, requiring intubation. A repeat brain MRI demonstrated new bilateral supratentorial lesions associated with venous sinus thrombosis, hemorrhage, and midline shift. Anti-MOG antibody was present at a high titer. CSF IL-6 protein was >2,000 times above the upper limits of normal. He improved after plasma exchange, then began monthly treatment alone with anti-IL-6 receptor antibody, tocilizumab, and has remained stable. This case highlights how adult-onset MOGAD, like childhood ADEM, can rapidly become life-threatening. The markedly elevated CSF IL-6 observed here supports consideration for evaluating CSF cytokines more broadly in patients with acute MOGAD.

Assessment of dietary intake and its inflammatory potential in persons with pediatric-onset multiple sclerosis.

OBJECTIVE: To compare diet and the modified dietary inflammatory index (mDII) between individuals with pediatric-onset multiple sclerosis (PoMS), monophasic acquired demyelinating syndromes (monoADS), and controls. METHODS: The association between diet, mDII, and disease status was examined in 131 individuals with PoMS/monoADS/controls (38/45/48) using logistic regression. RESULTS: The associations between diet and PoMS were modest, reaching significance for whole grain intake (adjusted odds ratio, aOR=0.964, 95 % confidence intervals, CI:0.934-0.995) but not mDII (aOR=1.20, 95 %CI:0.995-1.46) versus controls. No findings for monoADS reached significance versus controls. CONCLUSIONS: Individuals with PoMS, but not monoADS, had lower dietary whole grain intake than controls.

Central vein sign and trigeminal lesions of multiple sclerosis visualised by 7T MRI.

BACKGROUND: Although trigeminal nerve involvement is a characteristic of multiple sclerosis (MS), its prevalence across studies varies greatly due to MRI resolution and cohort selection bias. The mechanism behind the site specificity of trigeminal nerve injury is still unclear. We aim to determine the prevalence of trigeminal nerve involvement in patients with MS in a consecutive 7T brain MRI cohort. METHODS: This observational cohort originates from an ongoing China National Registry of Neuro-Inflammatory Diseases. Inclusion criteria were the following: age 18 years or older, diagnosis of MS according to the 2017 McDonald criteria and no clinical relapse within the preceding 3 months. Each participant underwent 7T MAGNETOM Terra scanner (Siemens, Erlangen, Germany), using a 32-channel phased array coil at Beijing Tiantan Hospital. T1-weighted magnetisation-prepared rapid acquisition gradient echoes, fluid-attenuated inversion recovery (FLAIR) and fluid and white matter suppression images were used to identify lesions. FLAIR* and T2* weighted images were used to identify central vein sign (CVS) within the trigeminal lesions. RESULTS: 120 patients underwent 7T MRI scans between December 2021 and May 2023. 19/120 (15.8%) patients had a total of 45 trigeminal lesions, of which 11/19 (57.9%) were bilateral. The linear lesions extended along the trigeminal nerve, from the root entry zone (REZ) (57.8%, 26/45) to the pontine-medullary nucleus (42.2%, 19/45). 26.9% (7/26) of the lesions in REZ showed a typical central venous sign. CONCLUSION: In this 7T MRI cohort, the prevalence of trigeminal nerve involvement was 15.8%. Characteristic CVS was detected in 26.9% of lesions in REZ. This suggests an inflammatory demyelination mechanism of trigeminal nerve involvement in MS.

Gene-environment interactions: Epstein-Barr virus infection and risk of pediatric-onset multiple sclerosis.

BACKGROUND AND OBJECTIVE: Prior Epstein-Barr virus (EBV) infection is associated with an increased risk of pediatric-onset multiple sclerosis (POMS) and adult-onset multiple sclerosis (MS). It has been challenging to elucidate the biological mechanisms underlying this association. We examined the interactions between candidate human leukocyte antigen (HLA) and non-HLA variants and childhood EBV infection as it may provide mechanistic insights into EBV-associated MS. METHODS: Cases and controls were enrolled in the Environmental and Genetic Risk Factors for Pediatric MS study of the US Network of Pediatric MS Centers. Participants were categorized as seropositive and seronegative for EBV-viral capsid antigen (VCA). The association between prior EBV infection and having POMS was estimated with logistic regression. Interactions between EBV serostatus, major HLA MS risk factors, and non-HLA POMS risk variants associated with response to EBV infection were also evaluated with logistic regression. Models were adjusted for sex, age, genetic ancestry, and the mother's education. Additive interactions were calculated using relative risk due to interaction (RERI) and attributable proportions (APs). RESULTS: A total of 473 POMS cases and 702 controls contributed to the analyses. Anti-VCA seropositivity was significantly higher in POMS cases compared to controls (94.6% vs 60.7%, p < 0.001). There was evidence for additive interaction between childhood EBV infection and the presence of the HLA-DRB1*15 allele (RERI = 10.25, 95% confidence interval (CI) = 3.78 to 16.72; AP = 0.61, 95% CI = 0.47 to 0.75). There was evidence for multiplicative interaction (p < 0.05) between childhood EBV infection and the presence of DRB1*15 alleles (odds ratio (OR) = 3.43, 95% CI = 1.06 to 11.07). Among the pediatric MS variants also associated with EBV infection, we detected evidence for additive interaction (p = 0.02) between prior EBV infection and the presence of the GG genotype in risk variant (rs2255214) within CD86 (AP = 0.30, 95% CI = 0.03 to 0.58). CONCLUSION: We report evidence for interactions between childhood EBV infection and DRB1*15 and the GG genotype of CD86 POMS risk variant. Our results suggest an important role of antigen-presenting cells (APCs) in EBV-associated POMS risk.

Clinical and Imaging Findings in Children with Myelin Oligodendrocyte Glycoprotein Antibody Associated Disease (MOGAD): From Presentation to Relapse.

BACKGROUND AND PURPOSE: Myelin oligodendrocyte glycoprotein-antibody associated disease (MOGAD) is an increasingly recognized cause of demyelinating disease in children. The purpose of this study is to characterize the CNS imaging manifestations of pediatric MOGAD and identify clinical and imaging variables associated with relapse. MATERIALS AND METHODS: We retrospectively identified children with serum antibody-positive MOGAD evaluated at our institution between 1997 and 2020. Clinical and demographic data were collected. MRIs of the brain, orbit, and spine at presentation and relapse were reviewed for location and pattern of abnormality. RESULTS: Among 61 cases (34 girls), mean age at presentation was 7 years (IQR 4-11). At presentation, there was imaging involvement of the brain in 78.6% (44/56), optic pathway in 55.4% (31/56), and spine in 19.6% (11/56). Brain involvement was commonly in the frontal (70.5%, 31/44) and subcortical (75%, 33/44) white matter, with involvement of the thalamus and pons in 47.7% each (21/44). Optic neuritis (ON) was commonly bilateral (80.6%, 25/31) involving intraorbital segments (77.4%, 24/31). Spinal cord lesions were typically cervical (72.7%, 8/11) and multifocal (72.7%, 8/11).The imaging patterns were age-dependent; children ≤9 years more commonly demonstrated ADEM-like imaging pattern at presentation (39.4%, 13/33) and first relapse (8/23, 34.8%), while children >9 years more commonly had ON at presentation (34.8%, 8/23, P = .001) and FLAIR-hyperintense lesions in anti-MOG-associated encephalitis with seizures at first relapse (5/18, 27.8%, P = .008). CONCLUSIONS: We describe the CNS imaging findings in pediatric MOGAD. The imaging pattern is age-dependent at presentation and first relapse. Younger age at presentation is associated with longer time to relapse.

Short-chain fatty acid producers in the gut are associated with pediatric multiple sclerosis onset.

OBJECTIVE: The relationship between multiple sclerosis and the gut microbiome has been supported by animal models in which commensal microbes are required for the development of experimental autoimmune encephalomyelitis. However, observational study findings in humans have only occasionally converged when comparing multiple sclerosis cases and controls which may in part reflect confounding by comorbidities and disease duration. The study of microbiome in pediatric-onset multiple sclerosis offers unique opportunities as it is closer to biological disease onset and minimizes confounding by comorbidities and environmental exposures. METHODS: A multicenter case-control study in which 35 pediatric-onset multiple sclerosis cases were 1:1 matched to healthy controls on age, sex, self-reported race, ethnicity, and recruiting site. Linear mixed effects models, weighted correlation network analyses, and PICRUSt2 were used to identify microbial co-occurrence networks and for predicting functional abundances based on marker gene sequences. RESULTS: Two microbial co-occurrence networks (one reaching significance after adjustment for multiple comparisons; q < 0.2) were identified, suggesting interdependent bacterial taxa that exhibited association with disease status. Both networks indicated a potentially protective effect of higher relative abundance of bacteria observed in these clusters. Functional predictions from the significant network suggested a contribution of short-chain fatty acid producers through anaerobic fermentation pathways in healthy controls. Consistent family-level findings from an independent Canadian-US study (19 case/control pairs) included Ruminococaccaeae and Lachnospiraceae (p < 0.05). Macronutrient intake was not significantly different between cases and controls, minimizing the potential for dietary confounding. INTERPRETATION: Our results suggest that short-chain fatty acid producers may be important contributors to multiple sclerosis onset.

A cross-sectional study of MRI features and the gut microbiome in pediatric-onset multiple sclerosis.

OBJECTIVE: To identify gut microbiome features associated with MRI lesion burden in persons with pediatric-onset multiple sclerosis (symptom onset <18 years). METHODS: A cross-sectional study involving the Canadian Paediatric Demyelinating Disease Network study participants. Gut microbiome features (alpha diversity, phylum- and genus-level taxa) were derived using 16S rRNA sequencing from stool samples. T1- and T2-weighted lesion volumes were measured on brain MRI obtained within 6 months of stool sample procurement. Associations between the gut microbiota and MRI metrics (cube-root-transformed) were assessed using standard and Lasso regression models. RESULTS: Thirty-four participants were included; mean ages at symptom onset and MRI were 15.1 and 19.0 years, respectively, and 79% were female. The T1- and T2-weighted lesion volumes were not significantly associated with alpha diversity (age and sex-adjusted p > 0.08). At the phylum level, high Tenericutes (relative abundance) was associated with higher T1 and T2 volumes (ß coefficient = 0.25, 0.37) and high Firmicutes, Patescibacteria or Actinobacteria with lower lesion volumes (ß coefficient = -0.30 to -0.07). At the genus level, high Ruminiclostridium, whereas low Coprococcus 3 and low Erysipelatoclostridium were associated with higher lesion volumes. INTERPRETATION: Our study characterized the gut microbiota features associated with MRI lesion burden in pediatric-onset MS, shedding light onto possible pathophysiological mechanisms.

Gene-environment interactions and risk of pediatric-onset multiple sclerosis associated with time spent outdoors.

BACKGROUND: Our previous study identified a significant association between lower time spent outdoors, as a proxy of sun exposure, and a higher risk of pediatric-onset multiple sclerosis (POMS). UV radiation modulates the expression of several genes, but it is unknown whether these genes modify the effect of sun exposure on POMS risk. METHODS: In an age- and sex-matched case-control study, we evaluated the additive and multiplicative interactions between time spent outdoors and genetic non-HLA risk variants for developing POMS within the metabolic pathways of UV radiation, including CD28(rs6435203), CD86(rs9282641), and NFkB1(rs7665090) and the top two HLA risk factors (presence of DRB1×15 and absence of A*02). RESULTS: In an adjusted model (332 POMS cases, 534 healthy controls), greater time compared to <30 min/day spent outdoors during the prior summer and higher UV radiation dose were associated with decreased odds of POMS (OR 0.66, 95% CI 0.56-0.78, p < 0.001; OR 0.78, 95 % CI 0.62-0.98, p = 0.04, respectively). No significant additive or multiplicative interactions were found between risk factors. CONCLUSIONS: The exploration of gene-environment interactions in the risk of developing MS can unravel the underlying mechanisms involved. Although we do not have evidence that our candidate genes contribute to interactions, other genes may.

Susceptibility-based imaging aids accurate distinction of pediatric-onset MS from myelin oligodendrocyte glycoprotein antibody-associated disease.

BACKGROUND: Myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD) and pediatric-onset multiple sclerosis (POMS) share clinical and magnetic resonance imaging (MRI) features but differ in prognosis and management. Early POMS diagnosis is essential to avoid disability accumulation. Central vein sign (CVS), paramagnetic rim lesions (PRLs), and central core lesions (CCLs) are susceptibility-based imaging (SbI)-related signs understudied in pediatric populations that may help discerning POMS from MOGAD. METHODS: T2-FLAIR and SbI (three-dimensional echoplanar imaging (3D-EPI)/susceptibility-weighted imaging (SWI) or similar) were acquired on 1.5T/3T scanners. Two readers assessed CVS-positive rate (%CVS+), and their average score was used to build a receiver operator curve (ROC) assessing the ability to discriminate disease type. PRLs and CCLs were identified using a consensual approach. RESULTS: The %CVS+ distinguished 26 POMS cases (mean age 13.7 years, 63% females, median EDSS 1.5) from 14 MOGAD cases (10.8 years, 35% females, EDSS 1.0) with ROC = 1, p < 0.0001, (cutoff 41%). PRLs were only detectable in POMS participants (mean 2.1±2.3, range 1-10), discriminating the two conditions with a sensitivity of 69% and a specificity of 100%. CCLs were more sensitive (81%) but less specific (71.43%). CONCLUSION: The %CVS+ and PRLs are highly specific markers of POMS. After proper validation on larger multicenter cohorts, consideration should be given to including such imaging markers for diagnosing POMS at disease onset.

Serum neurofilament light chain reference database for individual application in paediatric care: a retrospective modelling and validation study.

BACKGROUND: Neurological conditions represent an important driver of paediatric disability burden worldwide. Measurement of serum neurofilament light chain (sNfL) concentrations, a specific marker of neuroaxonal injury, has the potential to contribute to the management of children with such conditions. In this context, the European Medicines Agency recently declared age-adjusted reference values for sNfL a top research priority. We aimed to establish an age-adjusted sNfL reference range database in a population of healthy children and adolescents, and to validate this database in paediatric patients with neurological conditions to affirm its clinical applicability. METHODS: To generate a paediatric sNfL reference dataset, sNfL values were measured in a population of healthy children and adolescents (aged 0-22 years) from two large cohorts in Europe (the Coronavirus Antibodies in Kids from Bavaria study, Germany) and North America (a US Network of Paediatric Multiple Sclerosis Centers paediatric case-control cohort). Children with active or previous COVID-19 infection or SARS-CoV-2 antibody positivity at the time of sampling, or a history of primary systemic or neurological conditions were excluded. Linear models were used to restrospectively study the effect of age and weight on sNfL concentrations. We modelled the distribution of sNfL concentrations as a function of age-related physiological changes to derive reference percentile and Z score values via a generalised additive model for location, scale, and shape. The clinical utility of the new reference dataset was assessed in children and adolescents (aged 1-19 years) with neurological diseases (epilepsy, traumatic brain injury, bacterial CNS infections, paediatric-onset multiple sclerosis, and myelin oligodendrocyte glycoprotein antibody-associated disease) from the paediatric neuroimmunology clinic at the University of California San Francisco (San Francisco, CA, USA) and the Children's Hospital of the University of Regensburg (Regensburg, Germany). FINDINGS: Samples from 2667 healthy children and adolescents (1336 [50·1%] girls and 1331 [49·9%] boys; median age 8·0 years [IQR 4·0-12·0]) were used to generate the reference database covering neonatal age to adolescence (target age range 0-20 years). In the healthy population, sNfL concentrations decreased with age by an estimated 6·8% per year until age 10·3 years (estimated multiplicative effect per 1 year increase 0·93 [95% CI 0·93-0·94], p<0·0001) and was mostly stable thereafter up to age 22 years (1·00 [0·52-1·94], p>0·99). Independent of age, the magnitude of the effect of weight on sNfL concentrations was marginal. Samples from 220 children with neurological conditions (134 [60·9%] girls and 86 [39·1%] boys; median age 14·7 years [IQR 10·8-16·5]) were used to validate the clinical utility of the reference Z scores. In this population, age-adjusted sNfL Z scores were higher than in the reference population of healthy children and adolescents (p<0·0001) with higher effect size metrics (Cohen's d=1·56) compared with the application of raw sNfL concentrations (d=1·28). INTERPRETATION: The established normative sNfL values in children and adolescents provide a foundation for the clinical application of sNfL in the paediatric population. Compared with absolute sNfL values, the use of sNfL Z score was associated with higher effect size metrics and allowed for more accurate estimation of the extent of ongoing neuroaxonal damage in individual patients. FUNDING: Swiss National Science Foundation, US National Institutes of Health, and the National Multiple Sclerosis Society.

Differential diagnosis of suspected multiple sclerosis: an updated consensus approach.

Accurate diagnosis of multiple sclerosis requires careful attention to its differential diagnosis-many disorders can mimic the clinical manifestations and paraclinical findings of this disease. A collaborative effort, organised by The International Advisory Committee on Clinical Trials in Multiple Sclerosis in 2008, provided diagnostic approaches to multiple sclerosis and identified clinical and paraclinical findings (so-called red flags) suggestive of alternative diagnoses. Since then, knowledge of disorders in the differential diagnosis of multiple sclerosis has expanded substantially. For example, CNS inflammatory disorders that present with syndromes overlapping with multiple sclerosis can increasingly be distinguished from multiple sclerosis with the aid of specific clinical, MRI, and laboratory findings; studies of people misdiagnosed with multiple sclerosis have also provided insights into clinical presentations for which extra caution is warranted. Considering these data, an update to the recommended diagnostic approaches to common clinical presentations and key clinical and paraclinical red flags is warranted to inform the contemporary clinical evaluation of patients with suspected multiple sclerosis.

Demographic Features and Clinical Course of Patients With Pediatric-Onset Multiple Sclerosis on Newer Disease-Modifying Treatments.

BACKGROUND: Treatment of pediatric-onset multiple sclerosis (POMS) is challenging given the lack of safety and efficacy data in the pediatric population for many of the disease-modifying treatments (DMTs) approved for use in adults with MS. Our objective was to describe the demographic features and clinical and radiologic course of patients with POMS treated with the commonly used newer DMTs within the US Network of Pediatric MS Centers (NPMSC). METHODS: This is an analysis of prospectively collected data from patients who initiated treatment before age 18 with the DMTs listed below at the 12 regional pediatric MS referral centers participating in the NPMSC. RESULTS: One hundred sixty-eight patients on dimethyl fumarate, 96 on fingolimod, 151 on natalizumab, 166 on rituximab, and 37 on ocrelizumab met criteria for analysis. Mean age at DMT initiation ranged from 15.2 to 16.5 years. Disease duration at the time of initiation of index DMT ranged from 1.1 to 1.6 years with treatment duration of 0.9-2.0 years. Mean annualized relapse rate (ARR) in the year prior to initiating index DMT ranged from 0.4 to 1.0. Mean ARR while on index DMT ranged from 0.05 to 0.20. New T2 and enhancing lesions occurred in 75%-88% and 55%-73% of the patients, respectively, during the year prior to initiating index DMT. After initiating index DMT, new T2 and enhancing lesions occurred in 0%-46% and 11%-34% patients, respectively. Rates of NEDA-2 (no evidence of disease activity) ranged from 76% to 91% at 6 months of treatment with index DMTs and 66% to 84% at 12 months of treatment with index DMTs. CONCLUSIONS: Though limited by relatively short treatment duration with the index DMTs, our data suggest clinical and MRI benefit, as well as high rates of NEDA-2, in a large number of POMS patients, which can be used to guide future studies in this population.

High-dose vitamin D3 supplementation in relapsing-remitting multiple sclerosis: a randomised clinical trial.

Background: Vitamin D insufficiency is associated with risk of multiple sclerosis (MS) relapse; whether supplementation influences prognosis is unknown. The Vitamin D to Ameliorate MS (VIDAMS) trial aimed to determine if high dose (5000 International Units (IU)/day) versus low dose (600 IU/day) vitamin D3, added to daily glatiramer acetate (GA), reduced the risk of clinical relapse in people with established relapsing remitting MS (RRMS) over 96 weeks. Methods: VIDAMS is a randomised, phase 3, double-blind, multi-centre, controlled trial conducted at sixteen neurology clinics in the United States. Participants with MAGNIMS 2010 RRMS, aged 18-50 years, with recent disease activity were eligible to enroll if they had an Expanded Disability Status Scale score ≤4.0; minimum serum 25-hydroxyvitamin D level of 15 ng/ml within 30 days of screening; and average ≤ 1000 IU supplemental vitamin D3 daily in the 90 days prior to screening. Of 203 screened, 183 were eligible for the 30-day run-in to assess GA adherence, after which 172 were randomised 1:1 to low dose vitamin D3 (LDVD) or high dose vitamin D3 (HDVD), and were followed every 12 weeks for 96 weeks. The primary outcome was the proportion that experienced a confirmed relapse and analyses used Kaplan Meier and Cox proportional hazards models. 165 participants returned for ≥1 follow-up visit and were included in the primary and safety analyses; 140 completed a week 96 visit. This study was registered with ClinicalTrials.gov, NCT01490502. Findings: Between March 22, 2012 and March 8, 2019, 172 participants were enrolled and randomised (83 LDVD, 89 HDVD) and differed at baseline only in gender and race: more males received HDVD (31%) than LDVD (16%), and fewer Black participants received HDVD (12%) than LDVD (22%). Among 165 participants with at least one follow-up visit, the proportion experiencing confirmed relapse did not differ between LDVD and HDVD [at 96 weeks: 32% vs. 34%, p = 0.60; hazard ratio (HR): 1.17 (0.67, 2.05), p = 0.57]. There was no hypercalcaemia. Three participants developed nephrolithiasis or ureterolithiasis (1 in the LDVD and 2 in the HDVD group). Two were possibly related to study drug; and one was presumed related to concomitant treatment with topiramate for migraine. Interpretation: VIDAMS provides evidence that HDVD supplementation, added to GA, does not reduce the risk of clinical relapse in people with RRMS. Taken together with the null findings of previous trials, these results suggest that prescribing higher doses of vitamin D for purposes of modifying the RRMS course may not be beneficial. Funding: This investigation was supported by a grant from the National Multiple Sclerosis Society (RG 4407A2/1). Teva Neuroscience, Inc. provided Copaxone (GA) for the duration of the trial.

Several serum lipid metabolites are associated with relapse risk in pediatric-onset multiple sclerosis.

BACKGROUND: The circulating metabolome is altered in multiple sclerosis (MS), but its prognostic capabilities have not been extensively explored. Lipid metabolites might be of particular interest due to their multiple roles in the brain, as they can serve as structural components, energy sources, and bioactive molecules. Gaining a deeper understanding of the disease may be possible by examining the lipid metabolism in the periphery, which serves as the primary source of lipids for the brain. OBJECTIVE: To determine if altered serum lipid metabolites are associated with the risk of relapse and disability in children with MS. METHODS: We collected serum samples from 61 participants with pediatric-onset MS within 4 years of disease onset. Prospective longitudinal relapse data and cross-sectional disability measures (Expanded Disability Status Scale [EDSS]) were collected. Serum metabolomics was performed using untargeted liquid chromatography and mass spectrometry. Individual lipid metabolites were clustered into pre-defined pathways. The associations between clusters of metabolites and relapse rate and EDSS score were estimated utilizing negative binomial and linear regression models, respectively. RESULTS: We found that serum acylcarnitines (relapse rate: normalized enrichment score [NES] = 2.1, q = 1.03E-04; EDSS: NES = 1.7, q = 0.02) and poly-unsaturated fatty acids (relapse rate: NES = 1.6, q = 0.047; EDSS: NES = 1.9, q = 0.005) were associated with higher relapse rates and EDSS, while serum phosphatidylethanolamines (relapse rate: NES = -2.3, q = 0.002; EDSS: NES = -2.1, q = 0.004), plasmalogens (relapse rate: NES = -2.5, q = 5.81E-04; EDSS: NES = -2.1, q = 0.004), and primary bile acid metabolites (relapse rate: NES = -2.0, q = 0.02; EDSS: NES = -1.9, q = 0.02) were associated with lower relapse rates and lower EDSS. CONCLUSION: This study supports the role of some lipid metabolites in pediatric MS relapses and disability.

High serum neurofilament levels are observed close to disease activity events in pediatric-onset MS and MOG antibody-associated diseases.

BACKGROUND: Serum neurofilament light chain (sNfL) is an emerging multiple sclerosis (MS) biomarker which measures neuro-axonal damage. However, understanding its temporal association with disease activity in pediatric-onset MS (POMS) and Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) remains limited. OBJECTIVE: To investigate the association of sNfL levels and time from disease activity in children with MS and MOGAD. METHODS: POMS and MOGAD cases with onset before 18 years of age were enrolled at the University of California San Francisco (UCSF) Regional Pediatric MS Center. Frequency-matched healthy subjects were recruited from general pediatric clinics. Serum samples were tested for MOG-IgG at Mayo Clinic using a live cell-based fluorescent activated cell sorting assay. sNfL levels were measured using single-molecule array (Simoa) technology measured in pg/mL. Data on demographics, clinical features, MRI, CSF, and treatment data were collected by chart review. RESULTS: We included 201 healthy controls healthy controls, 142 POMS, and 20 confirmed MOGAD cases with available sNfL levels. The median (IQR) age at the time of sampling was 15.6 (3.9), 15.5 (3.1), and 8.8 (4.1) years for controls, POMS, and MOGAD, respectively. Median sNfL levels (pg/ml) were higher in POMS (19.6) and MOGAD (32.7) cases compared to healthy controls (3.9) (p<0.001). sNfL levels ≥100 pg/ml were only detected within four months of a clinical event or MRI activity in both POMS and MOGAD cases. In addition, sNfL levels were higher in POMS patients with new/enlarged T2 and gadolinium-enhanced lesions than those without MRI activity within four months of sampling in POMS cases. CONCLUSION: High sNfL levels were observed close to clinical or MRI events in POMS and MOGAD. Our findings support sNfL as a biomarker of disease activity in pediatric demyelinating disorders.

A Phase 1 Study of Oral Vitamin D3 in Boys and Young Men With X-Linked Adrenoleukodystrophy.

Background and Objectives: There are no therapies for preventing cerebral demyelination in X-linked adrenoleukodystrophy (ALD). Higher plasma vitamin D levels have been linked to lower risk of inflammatory brain lesions. We assessed the safety and pharmacokinetics of oral vitamin D dosing regimens in boys and young men with ALD. Methods: In this open-label, multicenter, phase 1 study, we recruited boys and young men with ALD without brain lesions to a 12-month study of daily oral vitamin D3 supplementation. Our primary outcome was attainment of plasma 25-hydroxyvitamin D levels in target range (40-80 ng/mL) at 6 and 12 months. Secondary outcomes included safety and glutathione levels in the brain, measured with magnetic resonance spectroscopy, and blood, measured via mass spectrometry. Participants were initially assigned to a fixed dosing regimen starting at 2,000 IU daily, regardless of weight. After a midstudy safety assessment, we modified the dosing regimen, so all subsequent participants were assigned to a weight-stratified dosing regimen starting as low as 1,000 IU daily. Results: Between October 2016 and June 2019, we enrolled 21 participants (n = 12, fixed-dose regimen; n = 9, weight-stratified regimen) with a median age of 6.7 years (range: 1.9-22 years) and median weight of 20 kg (range: 11.7-85.5 kg). The number of participants achieving target vitamin D levels was similar in both groups at 6 months (fixed dose: 92%; weight stratified: 78%) and 12 months (fixed dose: 67%; weight stratified: 67%). Among the 12 participants in the fixed-dose regimen, half had asymptomatic elevations in either urine calcium:creatinine or plasma 25-hydroxyvitamin D; no laboratory deviations occurred with the weight-stratified regimen. Glutathione levels in the brain, but not the blood, increased significantly between baseline and 12 months. Discussion: Our vitamin D dosing regimens were well tolerated and achieved target 25-hydroxyvitamin D levels in most participants. Brain glutathione levels warrant further study as a biomarker for vitamin D and ALD. Classification of Evidence: This study provides Class IV evidence that fixed or weight-stratified vitamin D supplementation achieved target levels of 25-hydroxyvitamin D in boys and young men with X-ALD without brain lesions.

Characteristics of pediatric patients with multiple sclerosis and related disorders infected with SARS-CoV-2.

BACKGROUND: Pediatric patients with multiple sclerosis (POMS) and related disorders, clinically isolated syndrome (CIS), myelin oligodendrocyte glycoprotein antibody disorder (MOGAD), and neuromyelitis optica spectrum disorder (NMOSD), are commonly treated with immunosuppressants. Understanding the impact of SARS-CoV-2 infection in patients may inform treatment decisions. OBJECTIVE: Characterize SARS-CoV-2 infection prevalence and severity among a cohort of patients with POMS and related disorders, as well as the impact of disease-modifying therapies (DMTs). METHODS: POMS and related disorders patients enrolled in a large, prospective registry were screened for COVID-19 during standard-of-care neurology visits. If confirmed positive of having infection, further analysis was undertaken. RESULTS: Six hundred and sixty-nine patients were surveyed between March 2020 and August 2021. There were 73 confirmed COVID-19 infections. Eight of nine hospitalized patients (89%), and all patients admitted to the ICU were treated with B cell depleting therapy. The unadjusted odds ratio of hospitalization among those who tested positive of having had COVID-19 was 15.27 among those on B-cell-depleting therapy (p = 0.016). CONCLUSIONS: B-cell-depleting treatment was associated with a higher risk of COVID-19, higher rates of hospitalization, and ICU admission, suggesting this therapy carries a higher risk of severe infection in POMS and related disorders.

Silent findings: Examination of asymptomatic demyelination in a pediatric US cohort.

BACKGROUND AND OBJECTIVES: Limited data is available on children with evidence of silent central nervous system demyelination on MRI. We sought to characterize the population in a US cohort and identify predictors of clinical and radiologic outcomes. METHODS: We identified 56 patients such patients who presented with incidental MRI findings suspect for demyelination, enrolled through our US Network of Pediatric Multiple Sclerosis Centers, and conducted a retrospective review of 38 patients with MR images, and examined risk factors for development of first clinical event or new MRI activity. MRI were rated based on published MS and radiologically isolated syndrome (RIS) imaging diagnostic criteria. RESULTS: One-third had a clinical attack and ¾ developed new MRI activity over a mean follow-up time of 3.7 years. Individuals in our cohort shared similar demographics to those with clinically definite pediatric-onset MS. We show that sex, presence of infratentorial lesions, T1 hypointense lesions, juxtacortical lesion count, and callosal lesions were predictors of disease progression. Interestingly, the presence of T1 hypointense and infratentorial lesions typically associated with worse outcomes were instead predictive of delayed disease progression on imaging in subgroup analysis. Additionally, currently utilized diagnostic criteria (both McDonald 2017 and RIS criteria) did not provide statistically significant benefit in risk stratification. CONCLUSION: Our findings underscore the need for further study to determine if criteria currently used for pediatric patients with purely radiographic evidence of demyelination are sufficient.

Gene-environment interactions increase the risk of paediatric-onset multiple sclerosis associated with household chemical exposures.

BACKGROUND: We previously reported an association between household chemical exposures and an increased risk of paediatric-onset multiple sclerosis. METHODS: Using a case-control paediatric multiple sclerosis study, gene-environment interaction between exposure to household chemicals and genotypes for risk of paediatric-onset multiple sclerosis was estimated.Genetic risk factors of interest included the two major HLA multiple sclerosis risk factors, the presence of DRB1*15 and the absence of A*02, and multiple sclerosis risk variants within the metabolic pathways of common household toxic chemicals, including IL-6 (rs2069852), BCL-2 (rs2187163) and NFKB1 (rs7665090). RESULTS: 490 paediatric-onset multiple sclerosis cases and 716 controls were included in the analyses. Exposures to insect repellent for ticks or mosquitos (OR 1.47, 95% CI 1.06 to 2.04, p=0.019), weed control products (OR 2.15, 95% CI 1.51 to 3.07, p<0.001) and plant/tree insect or disease control products (OR 3.25, 95% CI 1.92 to 5.49, p<0.001) were associated with increased odds of paediatric-onset multiple sclerosis. There was significant additive interaction between exposure to weed control products and NFKB1 SNP GG (attributable proportions (AP) 0.48, 95% CI 0.10 to 0.87), and exposure to plant or disease control products and absence of HLA-A*02 (AP 0.56; 95% CI 0.03 to 1.08). There was a multiplicative interaction between exposure to weed control products and NFKB1 SNP GG genotype (OR 2.30, 95% CI 1.00 to 5.30) but not for other exposures and risk variants. No interactions were found with IL-6 and BCL-2 SNP GG genotypes. CONCLUSIONS: The presence of gene-environment interactions with household toxins supports their possible causal role in paediatric-onset multiple sclerosis.

Rare and low-frequency coding genetic variants contribute to pediatric-onset multiple sclerosis.

BACKGROUND: Rare genetic variants are emerging as important contributors to the heritability of multiple sclerosis (MS). Whether rare variants also contribute to pediatric-onset multiple sclerosis (POMS) is unknown. OBJECTIVE: To test whether genes harboring rare variants associated with adult-onset MS risk (PRF1, PRKRA, NLRP8, and HDAC7) and 52 major histocompatibility complex (MHC) genes are associated with POMS. METHODS: We analyzed DNA samples from 330 POMS cases and 306 controls from the US Network of Pediatric MS Centers and Kaiser Permanente Northern California for which Illumina ExomeChip genotypes were available. Using the gene-based method "SKAT-O," we tested the association between candidate genes and POMS risk. RESULTS: After correction for multiple comparisons, one adult-onset MS gene (PRF1, p = 2.70 × 10-3) and two MHC genes (BRD2, p = 5.89 × 10-5 and AGER, p = 7.96 × 10-5) were significantly associated with POMS. Results suggest these are independent of HLA-DRB1*1501. CONCLUSION: Findings support a role for rare coding variants in POMS susceptibility. In particular, rare minor alleles within PRF1 were more common among individuals with POMS compared to controls while the opposite was true for rare variants within significant MHC genes, BRD2 and AGER. These genes would not have been identified by common variant studies, emphasizing the merits of investigating rare genetic variation in complex diseases.