NMOSD and MOGAD.

OBJECTIVE: This article reviews the clinical features, MRI characteristics, diagnosis, and treatment of aquaporin-4 antibody-positive neuromyelitis optica spectrum disorder (AQP4-NMOSD) and myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD). The main differences between these disorders and multiple sclerosis (MS), the most common demyelinating disease of the central nervous system (CNS), are also highlighted. LATEST DEVELOPMENTS: The past 20 years have seen important advances in understanding rare demyelinating CNS disorders associated with AQP4 IgG and myelin oligodendrocyte glycoprotein (MOG) IgG. The rapidly expanding repertoire of immunosuppressive agents approved for the treatment of AQP4-NMOSD and emerging as potentially beneficial in MOGAD mandates prompt recognition of these diseases. Most of the recent literature has focused on the identification of clinical and MRI features that help distinguish these diseases from each other and MS, simultaneously highlighting major diagnostic pitfalls that may lead to misdiagnosis. An awareness of the limitations of currently available assays for AQP4 IgG and MOG IgG detection is fundamental for identifying rare false antibody positivity and avoiding inappropriate treatments. For this purpose, diagnostic criteria have been created to help the clinician interpret antibody testing results and recognize the clinical and MRI phenotypes associated with AQP4-NMOSD and MOGAD. ESSENTIAL POINTS: An awareness of the specific clinical and MRI features associated with AQP4-NMOSD and MOGAD and the limitations of currently available antibody testing assays is crucial for a correct diagnosis and differentiation from MS. The growing availability of effective treatment options will lead to personalized therapies and improved outcomes.

Bilateral pontine brachium lesions in one autoantibodies directed against MOG positive patient: A case report.

RATIONALE: Myelin oligodendrocyte glycoprotein (MOG) antibody-related disease is a relatively recent entity in inflammatory demyelinating disease. Its clinical presentation varies in severity and the lack of specific imaging features makes it easy to misdiagnose. We now report the case of a MOG antibody-positive patient who presented with diplopia and dizziness, and whose brain magnetic resonance imaging (MRI) showed abnormal signals in the bilateral pontine brachium. PATIENT CONCERNS: A previously healthy 52-year-old woman presented with diplopia and dizziness, and was hospitalized 4 days after onset. DIAGNOSES: Brain MRI demonstrated abnormal hyperintense signals in the bilateral pontine brachium on T2-weighted fluid attenuated inversion recovery imaging. MRI enhancement showed abnormal enhancement foci in bilateral pontine brachium and pons. Cerebrospinal fluid examination showed Oligoclonal IgG bands were negative. The IgG index was normal, and serum aquaporin-4 antibody was negative, while serum MOG-Ab was positive (1:100). In conjunction with a positive serum MOG antibody and exclusion of other diseases, diagnosis of MOG antibody-related disease was made. INTERVENTIONS: Intravenous methylprednisolone followed by oral corticosteroids. OUTCOMES: Symptoms resolved completely. At 4-month follow-up. Follow-up after 4 months showed disappearance of the abnormal signal in the left pontine brachium and diminution of abnormal high signal in the right compared to the previous one, and there was no recurrence 1 year after the onset of the disease. LESSONS: If brain MRI indicating bilateral, multiple, and diffuse abnormal signals in the pontine brachium, and a discrepancy between the clinical symptoms and the imaging severity, a diagnosis of demyelinating disease should be considered highly probable. In such cases, anti-MOG antibody testing is essential for further defining the etiology. The clinical phenotype and imaging manifestations of MOG antibody-positive brainstem encephalitis may lack sufficient specificity to be readily identifiable. Timely diagnosis and early glucocorticoid therapy are beneficial in improving prognosis and preventing recurrence.

[Anti-MOG antibody spectrum disease with annular-enhancing brain lesions in an immunocompetent child]. / Maladie du spectre des anticorps anti-MOG avec lésions cérébrales à rehaussement annulaire chez un enfant immunocompétent.

We report a rare diagnosis of ring-enhanced brain lesions. We describe a case of a 4-year-old immunocompetent girl presenting with a subacute alteration of her general condition and a walking disorder a few weeks after her return from a trip to Bangladesh. The etiological work-up revealed ring-enhanced brain lesions on magnetic resonance imaging (MRI). A wide range of etiologies, including infectious, tumoral and inflammatory causes, were considered. Given the clinical and radiological suspicion of neurocysticerosis, the patient was initially treated with corticosteroids and various infectious serologies were carried out, with negative results. Following a rapidly favourable clinical course on corticosteroids alone, further biological investigations revealed the presence of anti-MOG antibodies in both serum and cerebrospinal fluid, suggesting MOGAD (myelin oligodendrocyte glycoprotein antibody-associated disease). This case report highlights the complexity of diagnosing ring-enhanced brain lesions. It also draws attention to MOGAD in immunocompetent patients as a rare but possible etiology, to be systematically investigated in the presence of this type of lesion. Indeed, consideration of inflammatory and autoimmune causes is crucial for accurate diagnosis, enabling earlier targeted treatment.

Nous rapportons un diagnostic rare de lésions cérébrales à rehaussement annulaire. Il s'agit d'une jeune patiente immunocompétente de 4 ans présentant une altération subaiguë de son état général et un trouble de la marche survenus quelques semaines après son retour d'un voyage au Bengladesh. La mise au point étiologique a mis en évidence la présence de lésions cérébrales à rehaussement annulaire à l'imagerie par résonnance magnétique (IRM). Un large éventail d'étiologies a été envisagé. Devant la suspicion clinique et radiologique de neurocysticerose, la patiente a initialement été traitée avec des corticoïdes. Les différentes sérologies infectieuses sont revenues négatives. Face à une évolution clinique rapidement favorable sous corticothérapie seule, des investigations biologiques supplémentaires ont été réalisées révélant la présence d'anticorps anti-myéline oligodendrocyte (MOG) au niveau du sérum et du liquide céphalo-rachidien, suggérant une MOGAD (maladie auto-immune avec anticorps anti-myéline oligodendrocyte). Ce cas clinique met en lumière la complexité du diagnostic de ces lésions cérébrales. Il attire également l'attention sur la MOGAD chez des patients immunocompétents comme une étiologie possible à rechercher de manière systématique devant ce type de lésion. En effet, la prise en compte des causes inflammatoires et auto-immunes est cruciale pour un diagnostic précis permettant un traitement ciblé plus précoce.

Different Complement Activation Patterns Following C5 Cleavage in MOGAD and AQP4-IgG+NMOSD.

OBJECTIVES: In myelin oligodendrocyte glycoprotein IgG-associated disease (MOGAD) and aquaporin-4 IgG+ neuromyelitis optica spectrum disorder (AQP4+NMOSD), the autoantibodies are mainly composed of IgG1, and complement-dependent cytotoxicity is a primary pathomechanism in AQP4+NMOSD. We aimed to evaluate the CSF complement activation in MOGAD. METHODS: CSF-C3a, CSF-C4a, CSF-C5a, and CSF-C5b-9 levels during the acute phase before treatment in patients with MOGAD (n = 12), AQP4+NMOSD (n = 11), multiple sclerosis (MS) (n = 5), and noninflammatory neurologic disease (n = 2) were measured. RESULTS: CSF-C3a and CSF-C5a levels were significantly higher in MOGAD (mean ± SD, 5,629 ± 1,079 pg/mL and 2,930 ± 435.8 pg/mL) and AQP4+NMOSD (6,017 ± 3,937 pg/mL and 2,544 ± 1,231 pg/mL) than in MS (1,507 ± 1,286 pg/mL and 193.8 ± 0.53 pg/mL). CSF-C3a, CSF-C4a, and CSF-C5a did not differ between MOGAD and AQP4+NMOSD while CSF-C5b-9 (membrane attack complex, MAC) levels were significantly lower in MOGAD (17.4 ± 27.9 ng/mL) than in AQP4+NMOSD (62.5 ± 45.1 ng/mL, p = 0.0019). Patients with MOGAD with severer attacks (Expanded Disability Status Scale [EDSS] ≥ 3.5) had higher C5b-9 levels (34.0 ± 38.4 ng/m) than those with milder attacks (EDSS ≤3.0, 0.9 ± 0.7 ng/mL, p = 0.044). DISCUSSION: The complement pathway is activated in both MOGAD and AQP4+NMOSD, but MAC formation is lower in MOGAD, particularly in those with mild attacks, than in AQP4+NMOSD. These findings may have pathogenetic and therapeutic implications in MOGAD.

Overlapping syndrome of anti-MOG antibody-associated disease and anti-mGluR5 encephalitis manifested as optic neuritis: A case report.

RATIONALE: Anti-Myelin oligodendrocyte glycoprotein (MOG) and anti-metabotropic glutamate receptor 5 (mGluR5) double antibody positive encephalitis characterized by optic neuritis is extremely rare. We present a case of overlapping syndrome of MOG-IgG-associated disease and anti-mGluR5 encephalitis manifested as optic neuritis. PATIENT CONCERNS: A 60-year-old Chinses woman presented to the hospital with progressive vision loss and headache for 1 week. The cerebrospinal fluid examination was within the normal range. Visual evoked potentials study disclosed prolonged latency of P100 bilaterally. Fundus examination revealed indistinct boundaries of both optic discs. Her brain magnetic resonance imaging showed patchy hyperintensity in the posterior horn of the left ventricle and the left optic nerve. Her serum was positive for anti-MOG and anti-mGluR5 antibodies. DIAGNOSIS: The patient was diagnosed with overlapping syndrome of anti-MOG antibody-associated disease and anti-mGluR5 encephalitis mainly based on the clinical symptoms and further test of the antibody in serum. INTERVENTIONS AND OUTCOMES: She was subsequently subjected to empirical treatment with intravenous methylprednisolone. After discharge, she was given a tapering dose of oral prednisone, alongside mycophenolate mofetil. On outpatient follow-up, her symptoms showed no relapse after 1 month, and her condition remained stable. LESSONS: Early recognition of autoimmune encephalitis is crucial. The detection of cerebrospinal fluid and serum of autoimmune encephalitis and demyelinating diseases of the CNS, including MOG-IgG and mGluR5-IgG, should be strengthened in order to make a precise diagnosis and develop a comprehensive treatment plan in a timely manner.

CD19-Directed CAR T-Cells in a Patient With Refractory MOGAD: Clinical and Immunologic Follow-Up for 1 Year.

OBJECTIVES: In MOG antibody-associated disease (MOGAD), relapse prevention and the treatment approach to refractory symptoms are unknown. We report a patient with refractory MOGAD treated with CD19-directed CAR T-cells. METHODS: CD19-directed CAR T-cells (ARI-0001) were produced in-house by lentiviral transduction of autologous fresh leukapheresis and infused after a conventional lymphodepleting regimen. RESULTS: A 18-year-old man developed 2 episodes of myelitis associated with serum MOG-IgG, which were followed by 6 episodes of left optic neuritis (ON) and sustained the presence of MOG-IgG over 6 years despite multiple immunotherapies. After the sixth episode of ON, accompanied by severe residual visual deficits, CAR T-cell treatment was provided without complications. Follow-up of cell counts showed complete depletion of CD19+ B cells at day +7; reconstituted B cells at day +141 showing a naïve B-cell phenotype, and low or absent memory B cells and plasmablasts for 1 year. MOG-IgG titers have remained undetectable since CAR T-cell infusion. The patient had an early episode of left ON at day +29, when MOG-IgG was already negative, and since then he has remained free of relapses without immunotherapy for 1 year. DISCUSSION: This clinical case shows that CD19-directed CAR T-cell therapy is well-tolerated and is a potential treatment for patients with refractory MOGAD. CLASSIFICATION OF EVIDENCE: This provides Class IV evidence. It is a single observational study without controls.

Correlation of Visual System Biomarkers With Motor Deficits in Experimental Autoimmune Encephalomyelitis-Optic Neuritis.

Purpose: Experimental autoimmune encephalomyelitis (EAE) scoring, the most commonly used primary outcome metric for an in vivo model of multiple sclerosis (MS), is highly variable and subjective. Here we explored the use of visual biomarkers in EAE as more objective and clinically relevant primary outcomes. Methods: Motor impairment in myelin oligodendrocyte glycoprotein-immunized C57BL/6J mice was quantified using a five-point EAE grading scale. Pattern electroretinography (pERG) and retinal ganglion cell/inner plexiform layer (RGC/IPL) complex thickness were measured 60 days after induction. Optic nerve histopathology was analyzed at endpoint. Results: EAE mice displayed motor impairments ranging from mild to severe. Significant correlations were seen between pERG amplitude and last EAE score, mean EAE score, and cumulative EAE score. Optical coherence tomography (OCT) analysis demonstrated a significant correlation between thinning of the RGC/IPL complex and both EAE score and pERG amplitude. Optic nerve histopathology showed significant correlations between demyelination and cumulative EAE score, pERG amplitude, and RGC/IPL complex thickness, as well as between immune cell infiltration and cumulative EAE score, pERG amplitude, and RGC/IPL complex thickness in EAE mice. Conclusions: Unlike EAE scoring, pERG and OCT show direct measurement of retinal structure and function. Therefore we conclude that visual outcomes are well suited as a direct assessment of optic nerve involvement in this EAE model of MS while also being indicative of motor impairment. Translational Relevance: Standardizing directly translatable measurements as primary outcome parameters in the murine EAE model could lead to more rapid and relevant testing of new therapeutic approaches for mitigating MS.

Prognostic factors associated with disability in a cohort of neuromyelitis optica spectrum disorder and MOG-associated disease from a nationwide Portuguese registry.

INTRODUCTION: Neuromyelitis optica spectrum disorders (NMOSD) and MOG-associated disease (MOGAD) are an increasingly recognized group of demyelinating disorders of the central nervous system. Previous studies suggest that prognosis is predicted by older age at onset, number of relapses, the severity of the first attack and autoantibody status. OBJECTIVE: To study prognostic factors associated with disability progression and additional relapses in the 3-year follow-up of a national NMOSD/MOGAD cohort. RESULTS: Out of 180 of the initial Portuguese cohort, data on 82 patients was available at the end of the follow-up period (2019-2022). Two patients died. Twenty (24.4%) patients had one or more attack in this period (25 attacks in total), mostly transverse myelitis (TM) (56.0%) or optic neuritis (32.0%). MOGAD was significantly associated with a monophasic disease course (p = 0.03), with milder attacks (p = 0.01), while AQP4 + NMOSD was associated with relapses (p = 0.03). The most common treatment modalities were azathioprine (38.8%) and rituximab (18.8%). AQP4 + NMOSD more frequently required chronic immunosuppressive treatment, particularly rituximab (p = 0.01). Eighteen (22.5%) had an EDSS ≥6 at the end of the follow-up. AQP4 + NMOSD (p < 0.01) and the occurrence of transverse myelitis (TM) during disease (p = 0.04) correlated with an EDSS≥6 at the end of the follow-up period. MOGAD was significantly associated with an EDSS<6 (p < 0.01), and MOG+ cases that reached an EDSS>6 were significantly older (64.0 ± 2.8 versus 31.0 ± 17.1, p = 0.017). A bivariate logistic regression model including the serostatus and TM attacks during disease history successfully predicted 72.2% of patients that progressed to an EDSS≥6. CONCLUSION: This study highlights that myelitis predict increased disability (EDSS≥6) in NMOSD/MOGAG and AQP4 positivity is associated with increased disability.

[Modern pathogenetic treatment of rare demyelinating diseases]. / Sovremennoe patogeneticheskoe lechenie redkikh demieliniziruyushchikh zabolevanii.

Rare demyelinating diseases are a group of diseases whose pathogenesis is based on the process of demyelination. This group of diseases includes acute multiple encephalomyelitis (ADEM), opticoneuromyelitis spectrum diseases (NMOSD) and anti-myelin-oligodendrocyte glycoprotein-associated diseases (MOG-antibodies-associated diseases - MOGAD). Recently, new biological drugs for pathogenetic therapy have been developed, which have shown their effectiveness and good tolerability in comparison with therapy with first- and second-line drugs. Aim of the study - analysis of modern possibilities of pathogenetic treatment of patients with ADEM, seronegative and seropositive patients with NMOSD. The analysis was carried out on the basis of English-language publications in PubMed published over the past five years. This review summarizes current ideas about the possibilities of pathogenetic treatment of rare diseases. The advantages of using ravulizumab over other representatives of a new biological therapy associated with the use of monoclonal antibodies are shown. The analyzed data allow us to conclude that there is a significant development of pathogenetic treatment options for ZSONM. However, the effectiveness of new therapeutic biological drugs is still limited due to the lack of a large amount of clinical data to confirm, which creates the need to continue analyzing the experience of their use.

Early Maintenance Treatment Initiation and Relapse Risk Mitigation After a First Event of MOGAD in Adults: The MOGADOR2 Study.

BACKGROUND AND OBJECTIVES: Because myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is a recently identified autoimmune disorder, the natural history of MOGAD is still not well described. The objective of this study was to describe the long-term outcomes of adult patients with MOGAD. In addition, we aimed to identify factors affecting relapse risk and neurologic outcomes. METHODS: Clinical and biological data were obtained from patients with a first event of MOGAD and included in the French nationwide incident cohort between February 2014 and March 2017. Only patients aged 18 years or older at disease onset and with observation period of at least 3 months were included. Data were collected prospectively until July 2023 and registered in the dedicated French nationwide database. This form includes every relapse with phenotype description during follow-up, date of last assessment, final clinical outcome with Expanded Disability Status Scale score and visual acuity, and maintenance therapy. The probability of recurrence-free survival was assessed using the Kaplan-Meier method. RESULTS: We included 128 patients. The onset phenotype was isolated optic neuritis in 81 patients (63.3%) and isolated myelitis in 25 patients (19.5%). The median follow-up duration was 77.8 months (range 3.2-111.2), with 49 patients (38.3%) experienced at least one relapse. Median times from onset to second and third attacks were 3.2 (1.0-86.2) and 13.0 (2.6-64.4) months, respectively. At the last assessment, Expanded Disability Status Scale Score was ≥3 and ≥6 in 22 (17.2%) and 6 (4.7%) patients, respectively. Eighty patients received at least one maintenance treatment. This treatment was initiated after the first attack in 47 patients (36.7% of the whole cohort) and at the time of a second attack in 25 (19.5%). Multivariate analysis revealed that initiating maintenance treatment after the first attack was associated with a lower relapse risk (OR = 0.26 [95% CI 0.11-0.62], p = 0.002). In patients receiving maintenance therapy after first attack, the 2-year, 4-year, 6-year, and 8-year relapse risks were 11%, 15%, 20%, and 20%, respectively. In other patients, the risks were 41%, 46%, 51%, and 56%. DISCUSSION: The highest risk of a relapse in MOGAD occurs early, and initiating maintenance therapy from the first attack substantially reduced the relapse risk. CLASSIFICATION OF EVIDENCE: This study provides Class III evidence that initiating maintenance therapy from the first attack in patients with MOGAD reduces the relapse risk.

Applicability of the New Myelin Oligodendrocyte Glycoprotein Antibody-associated Disease Diagnostic Criteria in an Israeli Cohort.

BACKGROUND: Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is a rare autoimmune demyelinating disorder of the central nervous system. Optic neuritis (ON) is the most common clinical manifestation of MOGAD in adults. In 2023, new MOGAD diagnostic criteria were proposed, highlighting the importance of supplemental criteria when MOG-immunoglobulin G (IgG) titers are unavailable. OBJECTIVES: To investigate the applicability of the 2023 MOGAD criteria in patients diagnosed with MOGAD and treated before the availability of MOG-IgG titers. METHODS: We conducted a retrospective chart review of patients classified as MOGAD between 2010 and 2023 at Rabin Medical Center. Patient demographics as well as clinical and imaging data were collected, including visual acuity, expanded disability status score, core demyelinating events, antibody status, and brain and optic nerve magnetic resonance imaging data. Patients fulfilling the 2023 MOGAD criteria were reported as definite MOGAD. RESULTS: Fifteen patients met the 2023 MOGAD diagnostic criteria despite lack of MOG-IgG titer. The most common supplemental criterion meeting the 2023 MOGAD criteria was optic disc edema (n=12, 80%), followed by longitudinal optic nerve involvement (53%), bilateral ON (40%), and perineural optic sheath enhancement (33%). CONCLUSIONS: All patients with a clinical diagnosis of MOG-ON in our cohort fulfilled the 2023 MOGAD criteria despite the lack of antibody titers. The 2023 MOGAD criteria can be reliably applied to Israeli cohorts, prior to availability of MOGAD IgG titers, with particular attention to additional supplemental criteria. Since the 2023 MOGAD criteria were published, MOGAD IgG titers have been added to routine testing at our facility.

Pearls & Oy-sters: Optic Neuritis as First Demyelinating Event During Pregnancy in 2 Young Hispanic Women: MS vs MOGAD.

Optic neuritis (ON) can present as the first demyelinating attack in both multiple sclerosis (MS) and myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD), which may require different treatment depending on the final diagnosis. We present 2 young Hispanic women who presented with ON during pregnancy, one of whom was diagnosed with MS and the other with MOGAD. We describe key clinical features to help differentiate between MS and MOGAD including ON features, brain and spinal MRI, CSF profiles, and serum MOG and aquaporin-4 (AQP-4) antibodies, which all can help guide clinicians to an ultimate diagnosis. Pregnancy is usually considered an immunotolerant state because complex immunologic shifts arising to support tolerance of the developing fetus seem to decrease the risk of relapses. However, relapses may still occur during pregnancy, and relapse rates increase immediately postpartum. Our cases raise the possibility that young Hispanic patients may face increased risk of demyelinating disease activity even during the relatively immunotolerant state of pregnancy. A high index of suspicion for demyelinating disease should be maintained to accelerate diagnosis and prevent disability.

Protocol of a prospective multicenter study on comorbidity impact on multiple sclerosis and antibody-mediated diseases of the central nervous system (COMMIT).

Comorbidities in patients with multiple sclerosis (MS) and antibody-mediated diseases of the central nervous system (CNS) including neuromyelitis optica spectrum disorder (NMOSD), and myelin oligodendrocyte glycoprotein (MOG)-antibody-associated disease (MOGAD) are common and may influence the course of their neurological disease. Comorbidity may contribute to neuronal injury and therefore limit recovery from attacks, accelerate disease progression, and increase disability. This study aims to explore the impact of comorbidity, particularly vascular comorbidity, and related risk factors on clinical and paraclinical parameters of MS, NMOSD and MOGAD. We propose COMMIT, a prospective multicenter study with longitudinal follow-up of patients with MS, NMOSD, and MOGAD, with or without comorbidities, as well as healthy subjects as controls. Subjects will be stratified by age, sex and ethnicity. In consecutive samples we will analyze levels of inflammation and neurodegeneration markers in both fluid and cellular compartments of the peripheral blood and cerebrospinal fluid (CSF) using multiple state-of-the-art technologies, including untargeted proteomics and targeted ultrasensitive ELISA assays and quantitative reverse transcription polymerase chain reaction (RT-qPCR) as well as high-dimensional single-cell technologies i.e., mass cytometry and single-cell RNA sequencing. Algorithm-based data analyses will be used to unravel the relationship between these markers, optical coherence tomography (OCT) and magnetic resonance imaging (MRI), and clinical outcomes including frequency and severity of relapses, long-term disability, and quality of life. The goal is to evaluate the impact of comorbidities on MS, NMOSD, and MOGAD which may lead to development of treatment approaches to improve outcomes of inflammatory demyelinating diseases of the CNS.

MOG CNS Autoimmunity and MOGAD.

At one time considered a possible form of neuromyelitis optica (NMO) spectrum disorder (NMOSD), it is now accepted that myelin oligodendrocyte glycoprotein (MOG) antibody (Ab)-associated disorder (MOGAD) is a distinct entity from either NMO or multiple sclerosis (MS) and represents a broad spectrum of clinical phenotypes. Whereas Abs targeting aquaporin-4 (AQP4) in NMO are pathogenic, the extent that anti-MOG Abs contribute to CNS damage in MOGAD is unclear. Both AQP4-specific Abs in NMO and MOG-specific Abs in MOGAD are predominantly IgG1, a T cell-dependent immunoglobulin (Ig) subclass. Key insights in neuroimmunology and MOGAD pathogenesis have been learned from MOG experimental autoimmune encephalomyelitis (EAE), described 2 decades before the term MOGAD was introduced. MOG-specific T cells are required in MOG EAE, and while anti-MOG Abs can exacerbate EAE and CNS demyelination, those Abs are neither necessary nor sufficient to cause EAE. Knowledge regarding the spectrum of MOGAD clinical and radiologic presentations is advancing rapidly, yet our grasp of MOGAD pathogenesis is incomplete. Understanding both the humoral and cellular immunology of MOGAD has implications for diagnosis, treatment, and prognosis.

[Related factors of acute symptomatic seizures and epilepsy in children with myelin oligodendrocyte glycoprotein antibody-associated disease].

Objective: To investigate the risk factors of acute symptomatic seizures (ASS) and epilepsy in children with myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD). Methods: A ambispective cohort study was used including 74 children with MOGAD who were admitted to the Department of Pediatrics of Peking University First Hospital from January 2013 to June 2023 and were followed up. Demographic information, clinical information, treatment status, ASS and epilepsy status were collected. The clinical phenotypes were classified. According to the presence or absence of ASS in the course of disease, the children and the course of disease were divided into groups with and without ASS. Chi-square test, Fisher exact test and Mann Whitney U test were used to analyze the correlation between symptoms and auxiliary examination characteristics and the occurrence of ASS in the two groups of children. Multivariate Logistic regression analysis was used for multivariate analysis. Results: The onset age of the 74 children with MOGAD was 6.58 (3.80, 9.67) years, including 38 females (51.4%) and 36 males (48.6%). The duration of the final follow-up was 2.67 (1.10, 4.12) years, with a total of 239 times acute clinical episodes. ASS occurred in 39.2% (29/74) children during the course of disease and in 29.3% (70/239) of attacks. The common phenotypes were ADEM (67 times (28.0%)), optic neuritis (37 times (15.4%)) and cerebral cortical encephalitis (31 times (13.0%)) in 239 times acute clinical episodes. The incidence of ASS in ADEM and cerebral cortical encephalitis phenotype was 28.4%(19/67) and 100.0% (31/31), respectively. Multivariate analysis showed that cortical involvement on magnetic resonance imaging during clinical attacks was an independent risk factor for ASS (ß=-1.49, OR=0.23) after excluding attacks involving only optic nerve or spinal cord (49 episodes). During the follow-up, 5 children (6.8%) had epilepsy, and all children with epilepsy had multiple clinical attacks of MOGAD and previous ASS. Conclusions: Cortical involvement on magnetic resonance imaging during clinical episodes is an independent risk factor for ASS in children with MOGAD. All MOGAD children with epilepsy had ASS and multiple MOGAD clinical episodes in the past.