Francisco, Carla

ABSTRACT Objective Little is known about shifting from pediatric to adult‐focused multiple sclerosis (MS) care. This study aims to explore transition of care and follow‐up in the US pediatric‐onset MS (POMS) population. Methods Surveys were distributed to 10 sites in the US Network of Pediatric MS Centers (US NPMSC) about transition‐of‐care practices. A cohort of POMS/clinically isolated syndrome (CIS) at 12 US NPMSC sites was analyzed. The primary comparison was between < 18 and ≥ 18‐years of age. The primary outcome was 1‐ and 2‐year lapse in last follow‐up visit, measured from last recorded database visit to data lock date or, if ≥ 18 years of age, up to 1 year after a patient reached their site's typical transition age, if earlier. Secondary outcomes were baseline factors associated with follow‐up lapse. The model was adjusted for preidentified confounders. Results Compared with < 18 years, age ≥ 18 was associated with greater hazard of 1‐ and 2‐year follow‐up lapse. In POMS/CIS, the estimated hazard was 1.61 for 1‐year lapse (95% confidence interval [CI] 1.32–1.97, p < 0.001) and 1.40 for 2‐year lapse (95% CI 1.11–1.76, p = 0.004). In POMS‐only, the estimated hazard was 1.70 for 1‐year lapse (95% CI 1.33–2.18, p < 0.001) and 1.49 for 2‐year lapse (95% CI 1.11–1.99, p = 0.007). Platform injectable disease‐modifying therapy was associated with greater and intravenous with lesser hazard of lapse in follow‐up, while MS was associated with lower hazard than CIS. Conclusion Variable transition‐of‐care practices and barriers were reported by major US POMS centers. Before typical transition age, age ≥ 18 was associated with greater hazard of 1‐ and 2‐year follow‐up lapse than < 18. Developing standardized, targeted transition‐of‐care practices in POMS may be important.

Autoimmune diseases arise when B and T lymphocytes lose tolerance to self. Yet in most disorders, the underlying molecular determinants, including autoantibodies, epitopes and lymphocyte clones that drive tissue injury remain undefined. Rapid-onset obesity with hypothalamic dysfunction, hypoventilation and autonomic dysregulation (ROHHAD) is a rare and often fatal pediatric neuroendocrine syndrome with strong evidence of antigen-driven paraneoplastic autoimmunity, including association with the intracellular autoantigen ZSCAN1. However, the effector immune circuit and the epitope-level determinants operating within the hypothalamus and brainstem have remained unknown. To address this challenge in ROHHAD and more broadly in autoimmune disease, we developed the Autoimmune Epitope and immunoGlobulin/Immune-receptor identification System (AEGIS), an integrated framework that links immune repertoires to their cognate self-epitopes. AEGIS combines B cell and T cell receptor profiling from sites of tissue injury with high-resolution epitope mapping, direct sequencing of antigen-specific autoantibodies, in silico antibody-antigen folding, selection, and T cell antigen discovery. Applied to a deeply phenotyped child with ROHHAD, AEGIS revealed a compartmentalized, clonally restricted immune response in which brain-deposited IgG and expanded cerebrospinal fluid B cell and CD4 T cell clonotypes converged on shared ZSCAN1 epitopes, resolved to minimal determinants and peptide-MHC ligands. These findings provide a clone- and epitope-linked mechanistic map of ROHHAD autoimmunity and establish a generalizable framework for identifying candidate pathogenic clones and antigens across diverse autoimmune diseases.

Objective To assess real‐world effectiveness of switching disease‐modifying therapy (DMT) in pediatric multiple sclerosis (MS) and clinically isolated syndrome (CIS) initially treated with platform injectables on disease activity. Methods Of 2615 pediatric‐onset demyelinating disease patients at 12 clinics in the United States (US) Network of Pediatric MS Centers, those with MS/CIS on initial therapy with a platform injectable who switched to another class of platform injectable, oral or infusion DMT were analyzed. Relapse rate was modeled with negative binomial regression, adjusted for preidentified confounders. Results A total of 212 children switched DMT before age 18 (67% female, 95% MS). Ninety‐three switched from injectable to injectable, 76 injectable to oral, and 43 injectable to infusion. Switchers to oral or infusion were older at onset (injectable 12.3 years, oral 13.5 years, and infusion 14.2 years) and switch (injectable 14.6 years, oral 16.0 years, and infusion 15.7 years). Switchers to infusion DMT were more likely to have enhancing lesions (injectable 45%, oral 28%, and infusion 67%). Compared to injectable (annualized relapse rate [ARR] = 0.88, 95% confidence interval [CI] = 0.52–1.48), relapse rates were lower for injectable to oral (ARR = 0.34, 95% CI = 0.20–0.57; rate ratio: 0.38, 95% CI = 0.21–0.69) and injectable to infusion (ARR = 0.18, 95% CI = 0.09–0.37; rate ratio: 0.21, 95% CI = 0.10–0.44) ( p < 0.001). Adjusted number needed to treat in person‐years to prevent 1 relapse with oral over injectable was 1.84 (95% CI = 1.03–8.69) and infusion over injectable 1.43 (95% CI = 1.00–3.88). Interpretation Switching from platform injectable to oral or infusion compared to other platform injectable DMT led to better disease control in pediatric MS. Long‐term safety data are required. ANN NEUROL 2026;99:715–729

Background and Objectives The genetic basis of adult-onset multiple sclerosis (MS) is well-studied, but less is known about pediatric-onset MS (pedMS), comprising approximately 5% of all MS onsets. Mendelian randomization (MR) studies have demonstrated evidence for a causal association between MS and both 25-hydroxyvitamin D [25(OH)D] serum levels and genetic variation related to vitamin D receptor (VDR) binding. The objective was to identify whether VDR binding variants (VDR-BVs) previously implicated in adult-onset MS were associated with pedMS using genetic instrumental variables (GIVs). Methods Using previously identified VDR-BVs to construct individual GIVs with two-sample MR, we investigated associations with pedMS in 725 cases and 592 controls of European ancestry from the US Network of Pediatric MS Centers. Associations between each VDR-BV and pedMS were estimated using logistic regression adjusting for the first three genome-wide principal components. A significant interaction between a VDR-BV and 25(OH)D GIV provided evidence for a causal association unbiased by pleiotropy. Results One VDR-BV, rs2531804, previously associated with adult-onset MS, was also significantly associated with pedMS after multiple testing correction. Discussion This study is the first to use VDR-BVs from previous MR studies to demonstrate causal differences in VDR binding at a locus contributing to pedMS susceptibility.

Objective The purpose of this study was to determine the frequency of myelin oligodendrocyte glycoprotein (MOG)‐IgG and aquaporin‐4 (AQP4)‐IgG among patients with pediatric‐onset multiple sclerosis (POMS) and healthy controls, to determine whether seropositive cases fulfilled their respective diagnostic criteria, to compare characteristics and outcomes in children with POMS versus MOG‐IgG‐associated disease (MOGAD), and identify clinical features associated with final diagnosis. Methods Patients with POMS and healthy controls were enrolled at 14 US sites through a prospective case–control study on POMS risk factors. Serum AQP4‐IgG and MOG‐IgG were assessed using live cell‐based assays. Results AQP4‐IgG was negative among all 1,196 participants, 493 with POMS and 703 healthy controls. MOG‐IgG was positive in 30 of 493 cases (6%) and zero controls. Twenty‐five of 30 patients positive with MOG‐IgG (83%) had MOGAD, whereas 5 of 30 (17%) maintained a diagnosis of multiple sclerosis (MS) on re‐review of records. MOGAD cases were more commonly in female patients (21/25 [84%] vs 301/468 [64%]; p = 0.044), younger age (mean = 8.2 ± 4.2 vs 14.7 ± 2.6 years; p < 0.001), more commonly had initial optic nerve symptoms (16/25 [64%] vs 129/391 [33%]; p = 0.002), or acute disseminated encephalomyelitis (ADEM; 8/25 [32%] vs 9/468 [2%]; p < 0.001), and less commonly had initial spinal cord symptoms (3/20 [15%] vs 194/381 [51%]; p = 0.002), serum Epstein–Barr virus (EBV) positivity (11/25 [44%] vs 445/468 [95%]; p < 0.001), or cerebrospinal fluid oligoclonal bands (5/25 [20%] vs 243/352 [69%]; p < 0.001). Interpretation MOG‐IgG and AQP4‐IgG were not identified among healthy controls confirming their high specificity for pediatric central nervous system (CNS) demyelinating disease. Five percent of those with prior POMS diagnoses ultimately had MOGAD; and none had AQP4‐IgG positivity. Clinical features associated with a final diagnosis of MOGAD in those with suspected MS included initial ADEM phenotype, younger age at disease onset, and lack of EBV exposure. ANN NEUROL 2023;93:271–284