The clinical spectrum and incidence of anti-MOG-associated acquired demyelinating syndromes in children and adults

Clinical Spectrum of Ophthalmic Manifestations in Myelin Oligodendrocyte Glycoprotein-Associated Disease (MOGAD): A Comprehensive Case Report

PURPOSE

To describe diverse ocular manifestations in a patient with Myelin oligodendrocyte glycoprotein-associated disease (MOGAD).

METHODS

A 15-year-old Indian male had severe loss of vision in one eye, followed by a recurrent attack of optic neuritis in the fellow eye a few weeks later. He had a history of vision loss, speech disturbances, altered sensorium and was a confirmed case of Myelin oligodendrocyte glycoprotein-associated disease (MOGAD). Apart from optic neuritis, other rare ophthalmic associations, namely, macular neuroretinopathy, retinal haemorrhages, severe optic nerve head edema, peri neuritis, and orbital enhancement on magnetic resonance imaging (MRI) were noted.

RESULTS

He responded dramatically to treatment with intravenous pulse steroids and relapses were controlled with long-term immunomodulation therapy.

CONCLUSION

This case report reiterates the need for early treatment with pulse steroids in MOGAD and depicts the heterogeneous involvement of various ocular structures in the disease.

NMOSD and MOGAD: an evolving disease spectrum

Neuromyelitis optica (NMO) spectrum disorder (NMOSD) is a relapsing inflammatory disease of the CNS, characterized by the presence of serum aquaporin 4 (AQP4) autoantibodies (AQP4-IgGs) and core clinical manifestations such as optic neuritis, myelitis, and brain or brainstem syndromes. Some people exhibit clinical characteristics of NMOSD but test negative for AQP4-IgG, and a subset of these individuals are now recognized to have serum autoantibodies against myelin oligodendrocyte glycoprotein (MOG) - a condition termed MOG antibody-associated disease (MOGAD). Therefore, the concept of NMOSD is changing, with a disease spectrum emerging that includes AQP4-IgG-seropositive NMOSD, MOGAD and double-seronegative NMOSD. MOGAD shares features with NMOSD, including optic neuritis and myelitis, but has distinct pathophysiology, clinical profiles, neuroimaging findings (including acute disseminated encephalomyelitis and/or cortical encephalitis) and biomarkers. AQP4-IgG-seronegative NMOSD seems to be a heterogeneous condition and requires further study. MOGAD can manifest as either a monophasic or a relapsing disease, whereas NMOSD is usually relapsing. This Review summarizes the history and current concepts of NMOSD and MOGAD, comparing epidemiology, clinical features, neuroimaging, pathology and immunology. In addition, we discuss new monoclonal antibody therapies for AQP4-IgG-seropositive NMOSD that target complement, B cells or IL-6 receptors, which might be applied to MOGAD in the near future.

The influence of MOGAD on diagnosis of multiple sclerosis using MRI

Myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD) is an immune-mediated demyelinating disease that is challenging to differentiate from multiple sclerosis (MS), as the clinical phenotypes overlap, and people with MOGAD can fulfil the current MRI-based diagnostic criteria for MS. In addition, the MOG antibody assays that are an essential component of MOGAD diagnosis are not standardized. Accurate diagnosis of MOGAD is crucial because the treatments and long-term prognosis differ from those for MS. This Expert Recommendation summarizes the outcomes from a Magnetic Resonance Imaging in MS workshop held in Oxford, UK in May 2022, in which MS and MOGAD experts reflected on the pathology and clinical features of these disorders, the contributions of MRI to their diagnosis and the clinical use of the MOG antibody assay. We also critically reviewed the literature to assess the validity of distinctive imaging features in the current MS and MOGAD criteria. We conclude that dedicated orbital and spinal cord imaging (with axial slices) can inform MOGAD diagnosis and also illuminate differential diagnoses. We provide practical guidance to neurologists and neuroradiologists on how to navigate the current MOGAD and MS criteria. We suggest a strategy that includes useful imaging discriminators on standard clinical MRI and discuss imaging features detected by non-conventional MRI sequences that demonstrate promise in differentiating these two disorders.

Clinico-radiologic Spectrum and Outcome of Pediatric Acquired Demyelinating Disorders of Central Nervous System: A Retrospective Indian Tertiary Care Hospital Cohort

BACKGROUND

Pediatric acquired demyelinating syndrome (ADS) constitutes a group of treatable disorders with acute neurologic dysfunction. Neuroimaging has played a significant role in diagnosis of ADS. We describe clinico-radiologic spectrum, outcomes, and comparison of the groups: acute disseminated encephalomyelitis (ADEM), neuromyelitis optica spectrum disorder (NMOSD), clinically isolated syndrome (CIS), multiple sclerosis (MS), and myelin oligodendrocyte glycoprotein antibody-associated disorders (MOGAD).

METHODS

Retrospective review of 70 children with ADS at a tertiary care hospital over 15 years (2008-2023) was performed. Diagnosis was assigned as per International Pediatric Multiple Sclerosis Study Group criteria 2016. Fisher's exact and chi-square tests were applied.

RESULTS

Thirty-nine boys and 31 girls aged 8.2 ± 4.0 years with CIS (n = 27), ADEM (n = 16), NMOSD (n = 13), MS (n = 1), and MOGAD (n = 13) were included. Clinical syndromes with positive significant association included polyfocal symptoms, encephalopathy in ADEM, optic neuritis (ON) in MOGAD, brainstem, area postrema syndrome in NMOSD. MOGAD presented with atypical presentations like prolonged fever (PF; 76.9%) and aseptic meningitis (23%). Seropositivity for myelin oligodendrocyte glycoprotein immunoglobulin-G was 62% and for NMO-IgG 2.6%. Neuroimaging of MOGAD showed lesions predominantly in basal ganglia/thalami (69.2%), optic nerve (46.2%), and cerebellum (46.2%). Imaging patterns between ADEM and MOGAD were comparable except for more ON (p = 0.004), spinal cord (p = 0.01), and cerebellar lesions (p = 0.03) in MOGAD. Area postrema lesion was unique to NMOSD. All patients received immunotherapy, of whom 91.4% (n = 64) had good recovery, 8.6% (n = 6) had functional limitation on modified Rankin scale at discharge, and 12 (17.1%) relapsed.

CONCLUSION

The largest group was CIS. Seropositivity of MOG was high with atypical presentations like PF and aseptic meningitis. Specific neuroimaging patterns correlated with ADS categories. Short-term outcome with immunotherapy was favorable in spite of relapses.

Investigating the 2023 MOGAD Criteria in Children and Adults With MOG-Antibody Positivity Within and Outside Attacks

BACKGROUND AND OBJECTIVES

The 2023 criteria for myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) perform well in adults but have not been assessed in children.

METHODS

This prospective observational nationwide study includes children and adults with demyelinating syndromes or encephalitis, whose serum or CSF was found MOG-immunoglobulin G (IgG) positive at Institut d'Investigacions Biomèdiques August Pi i Sunyer-Hospital Clínic of Barcelona (Spain). Exclusion criteria were lack of clinical information and follow-up <1 year, and serum unavailable for antibody testing. The primary outcome was to assess the accuracy of the 2023 MOGAD criteria, using as gold standard the most plausible diagnosis after a follow-up >1 year. MOGAD criteria were retrospectively applied assessing core syndromes, supportive clinical-radiological features, and MOG-IgG titers. Patients tested ≤3 months of a disease attack (acute phase) or afterward (remission) were considered separately. The positive predictive value (PPV) of the criteria (true-positive [patients classified as MOGAD and MOGAD diagnosis last follow-up] divided by total positive [all patients classified as MOGAD]), and its 95% CI, was calculated with the Wilson procedure.

RESULTS

A total of 257 patients (133 children) were included in the study (median age 15 years [interquartile range 6-38], 54% female). Among 202 patients assessed during a disease attack, 158 (78%) had high MOG-IgG serum titers, 36 (18%) low titers, and 8 (4%) antibodies only in CSF. No differences were identified between patients with high and low titers, but those with low titers were more likely to have an alternative diagnosis at last follow-up (2/36 [6%] vs 0/158, p = 0.012). Supportive features were present in 230 of 257 (89%) patients, regardless of age, MOG-IgG titers, and core syndromes except for optic neuritis in adults whose assessment with orbital MRI was not systematic. Overall, 240 of 257 (94%) patients were well classified by the MOGAD criteria (e.g., 236 eventually having MOGAD and 4 alternative diagnoses), and 17 were wrongly classified (e.g., 11 eventually having MOGAD and 6 alternative diagnoses). Although the criteria classified better during disease attacks than during remissions (187 [96%] vs 49 [89%] serum MOG-IgG-positive patients were well-classified, p = 0.038), the PPV was high in both settings (99% [95% CI 97-100] vs 98% [95% CI 89-100]).

DISCUSSION

The 2023 MOGAD criteria correctly identified most children and adults with MOGAD. The highest accuracy occurred when they were applied during disease attacks.

CLASSIFICATION OF EVIDENCE

This study provides Class IV evidence that the 2023 MOGAD criteria accurately identify adults and children with MOGAD.

MOG-antibody-associated transverse myelitis with the H-sign and unusual MRI enhancement: a case report and literature review

Transverse myelitis is the second most common symptoms in myelin oligodendrocyte antibody-associated diseases (MOGAD), causing obvious clinical manifestation. T2-hyperintense lesions mainly restricted to the gray matter in the spinal cord on axial magnetic resonance imaging, produce the H-sign, which is thought to be the typical finding of MOGAD. Contrast enhancement can be observed in some cases of myelin oligodendrocyte antibody-associated transverse myelitis (MOG-TM). However, reports on the enhancement pattern associated with the H-sign are rarely seen. In this report, we describe a case of pediatric MOG-TM in which the H-sign was observed without enhancement, while the surrounding white matter exhibited enhancement. This pattern contradicts the previously observed gray matter involvement. Then we reviewed the literatures of myelin oligodendrocyte antibody-positive myelitis to focus on the neuroimaging features and discuss the implications of our finding.

Radiological features in pediatric myelin oligodendrocyte glycoprotein antibody-associated disease-diagnostic criteria and lesion dynamics

The spectrum of acquired pediatric demyelinating syndromes has been expanding over the past few years, to include myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD), as a distinct neuroimmune entity, in addition to pediatric-onset multiple sclerosis (POMS) and aquaporin 4-IgG-seropositive neuromyelitis optica spectrum disorder (AQP4+NMOSD). The 2023 MOGAD diagnostic criteria require supporting clinical or magnetic resonance imaging (MRI) features in patients with low positive myelin oligodendrocyte glycoprotein IgG titers or when the titers are not available, highlighting the diagnostic role of imaging in MOGAD. In this review, we summarize the key diagnostic features in MOGAD, in comparison to POMS and AQP4+NMOSD. We describe the lesion dynamics both during attack and over time. Finally, we propose a guideline on timing of imaging in clinical practice.

Aggressive Course of Myelin Oligodendrocyte Glycoprotein Antibody-Associated Disease (MOGAD): An Illustration of Two Cases and Review of Literature

Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is a central nervous system demyelinating disease that has become a major source of morbidity among children and adults. In the first case, we present an 18-year-old Hispanic female with a recently resolved upper respiratory infection who presented with fever, headache, progressive quadriparesis, urinary retention, and encephalopathy. The hospital course involved autonomic dysfunction and prolonged intubation requiring tracheostomy and gastrostomy. Cerebrospinal fluid (CSF) showed pleocytosis and a positive MOG titer (1:40). Magnetic resonance imaging (MRI) showed longitudinally extensive cervicothoracic T2 hyperintensity and brain multifocal T2 hyperintensities. After high-dose intravenous methylprednisolone (IVMP) and intravenous immunoglobulin (IVIG), she had full neurological recovery by the last follow-up. The second case is of a 22-year-old Hispanic male who presented with progressive lower extremity paresthesia and weakness over six weeks. CSF demonstrated pleocytosis, elevated protein, oligoclonal bands, and MOG antibody. MRI revealed multiple subcortical T2-hyperintense lesions and enhancing midcervical and lower thoracic lesions. Treatment with IVMP led to minor improvement with discharge on steroid taper and azathioprine. The patient's disease progressed with a fluctuating course requiring two readmissions with upper extremity weakness, right optic neuritis, and urinary sphincteric dysfunction with neuroradiologic worsening. Treatment throughout multiple admissions included intravenous steroids, IVIG, plasmapheresis, mycophenolate mofetil, and rituximab with minimal improvement, symptom recurrence, and progression of multifocal lesions. The patient died four months after the symptom onset. These cases had markedly different treatment responses despite similar baseline characteristics. The difference in morbidity and disability burden highlights the importance of further investigation of this condition through clinical trials.

Development and validation of a claims-based algorithm to identify patients with Neuromyelitis Optica Spectrum disorder

INTRODUCTION

No validated algorithm exists to identify patients with neuromyelitis optica spectrum disorder (NMOSD) in healthcare claims data. We developed and tested the performance of a healthcare claims-based algorithm to identify patients with NMOSD.

METHODS

Using medical record data of 101 adults with NMOSD, multiple sclerosis (MS), or myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD), we tested the sensitivity and specificity of claims-based algorithms developed through interviews with neurologists. We tested the best-performing algorithm's face validity using 2016-2019 data from IBM MarketScan Commercial and Medicare Supplemental databases. Demographics and clinical characteristics were reported.

RESULTS

Algorithm inclusion criteria were age ≥ 18 years and (≥1 NMO diagnosis [or ≥ 1 transverse myelitis (TM) and ≥ 1 optic neuritis (ON) diagnosis] and ≥ 1 NMOSD drug) or (≥2 NMO diagnoses ≥90 days apart). Exclusion criteria were MS diagnosis or use of MS-specific drug after last NMO diagnosis or NMOSD drug; sarcoidosis diagnosis after last NMO diagnosis; or use of ≥1 immune checkpoint inhibitor. In medical record billing data of 50 patients with NMOSD, 30 with MS, and 21 with MOGAD, the algorithm had 82.0% sensitivity and 70.6% specificity. When applied to healthcare claims data, demographic and clinical features of the identified cohort were similar to known demographics of NMOSD.

CONCLUSIONS

This clinically derived algorithm performed well in medical records. When tested in healthcare claims, demographics and clinical characteristics were consistent with previous clinical findings. This algorithm will enable a more accurate estimation of NMOSD disease burden using insurance claims datasets.

MOG antibody-associated optic neuritis

Myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD) is a demyelinating disorder, distinct from multiple sclerosis (MS) and neuromyelitis optica spectrum disorder (NMOSD). MOGAD most frequently presents with optic neuritis (MOG-ON), often with characteristic clinical and radiological features. Bilateral involvement, disc swelling clinically and radiologically, and longitudinally extensive optic nerve hyperintensity with associated optic perineuritis on MRI are key characteristics that can help distinguish MOG-ON from optic neuritis due to other aetiologies. The detection of serum MOG immunoglobulin G utilising a live cell-based assay in a patient with a compatible clinical phenotype is highly specific for the diagnosis of MOGAD. This review will highlight the key clinical and radiological features which expedite diagnosis, as well as ancillary investigations such as visual fields, visual evoked potentials and cerebrospinal fluid analysis, which may be less discriminatory. Optical coherence tomography can identify optic nerve swelling acutely, and atrophy chronically, and may transpire to have utility as a diagnostic and prognostic biomarker. MOG-ON appears to be largely responsive to corticosteroids, which are often the mainstay of acute management. However, relapses are common in patients in whom follow-up is prolonged, often in the context of early or rapid corticosteroid tapering. Establishing optimal acute therapy, the role of maintenance steroid-sparing immunotherapy for long-term relapse prevention, and identifying predictors of relapsing disease remain key research priorities in MOG-ON.

MOG Antibody Disease: Nuances in Presentation, Diagnosis, and Management

PURPOSE OF REVIEW

Myelin oligodendrocyte glycoprotein antibody disease (MOGAD) is a distinct neuroinflammatory condition characterized by attacks of optic neuritis, transverse myelitis, and other demyelinating events. Though it can mimic multiple sclerosis and neuromyelitis optica spectrum disorder, distinct clinical and radiologic features which can discriminate these conditions are now recognized. This review highlights recent advances in our understanding of clinical manifestations, diagnosis, and treatment of MOGAD.

RECENT FINDINGS

Studies have identified subtleties of common clinical attacks and identified more rare phenotypes, including cerebral cortical encephalitis, which have broadened our understanding of the clinicoradiologic spectrum of MOGAD and culminated in the recent publication of proposed diagnostic criteria with a familiar construction to those diagnosing other neuroinflammatory conditions. These criteria, in combination with advances in antibody testing, should simultaneously lead to wider recognition and reduced incidence of misdiagnosis. In addition, recent observational studies have raised new questions about when to treat MOGAD chronically, and with which agent. MOGAD pathophysiology informs some of the relatively unique clinical and radiologic features which have come to define this condition, and similarly has implications for diagnosis and management. Further prospective studies and the first clinical trials of therapeutic options will answer several remaining questions about the peculiarities of this condition.

Optic Neuritis Leading to Vision Loss: A Case of MOG-Associated Disease with Successful Immunotherapy

BACKGROUND Myelin oligodendrocyte glycoprotein (MOG)-associated disease (MOGAD) is a recently described inflammatory demyelinating disease of the central nervous system (CNS), which needs to be distinguished from aquaporin-4 (AQP4)-IgG-positive neuromyelitis optica spectrum disorder (AQP4-IgG+NMOSD) and multiple sclerosis (MS). CASE REPORT A 42-year-old woman presenting with loss of vision due to optic neuritis was admitted to the Naval Medical Center in October 2022. She had optic disc edema, blurred visual margins, optic disc pallor, and deficient visual field in both eyes. Cranial magnetic resonance imaging (MRI) showed bilateral optic nerve thickening, tortuosity, and swelling, especially on the right side. Orbital MRI T2 sequence showed the typical "double track sign" change. The titers of MOG-IgG in CSF and serum were 1: 1 (+) and 1: 32 (+) separately, so MOGAD was diagnosed. The primary treatment was intravenous methylprednisolone for 2 weeks, after which the blurred vision improved and MRI showed the optic nerve lesions disappeared. She was discharged and oral corticosteroids were tapered gradually, and 1 month later, the symptom had vanished without recurrence, cranial MRI was normal, and MOG-IgG in CSF and serum were negative. Low-dose oral corticosteroids were continued for 6 months, with no relapse and normal cranial MRI, so we stopped corticosteroid therapy. At 1-year follow-up, the symptoms had not recurred. CONCLUSIONS A 42-year-old woman presented with loss of vision due to optic neuritis and positive antibody testing for MOG. MOGAD was diagnosed, and timely immunotherapy was effective.

A comparative study on anti-MOG and anti-AQP4 associated optic neuritis following mild COVID-19: insights from a Chinese single-center experience

Background

Research on the relationship between mild COVID-19 and the subsequent development of isolated optic neuritis (ON) with antibodies specific to myelin oligodendrocyte glycoprotein (MOG-ON) and aquaporin 4 (AQP4-ON) is limited, particularly case-control studies that directly compare these conditions within the same affected population.

Methods

A retrospective analysis of initial MOG-ON and AQP4-ON cases during the COVID-19 peak and subsequent months. Patients were classified as possible COVID-19 related ON (PCRON) or non-COVID-19 related ON (NCRON). The study compared epidemiology, comorbidities, and clinical features between these groups.

Results

Patients with MOG-ON tended to develop ON symptoms closer in time to a mild COVID-19 infection compared to those with AQP4-ON (6.87 ± 6.25 weeks vs. 11.06 ± 5.84 weeks; p = 0.038), a significantly higher proportion of patients with MON-ON developing symptoms within 6 weeks after COVID-19 compared to those with AQP4-ON (15/23 [65.2%] vs. 5/17 [29.4%]; p = 0.025). Comparing MOG-ON and AQP4-ON patients, MOG-ON patients were more likely to have a recent infection before ON onset (73.1% vs. 30%; p = 0.007) and had better peak and post-treatment visual acuity (p = 0.01; p < 0.001). In contrast, AQP4-ON patients frequently showed comorbid connective tissue diseases (30.0% vs. 0%, p = 0.004) and antinuclear antibody abnormalities (40.0% vs. 7.7%, p = 0.012). Among MOG-ON patients, PCRON had increased rates of atherosclerotic vascular diseases (AVDs) (53.3% vs. 9.1%, p = 0.036), phospholipid antibody abnormalities (60.0% vs. 18.2%, p = 0.04), and bilateral visual impairment (66.7% vs. 9.1%, p = 0.005). Multivariate analysis pinpointed AVDs (OR = 15.21, p = 0.043) and bilateral involvement (OR = 25.15, p = 0.015) as independent factors related to COVID-19 associated MOG-ON, with both being good discriminators for PCRON (AUC = 0.879). No differences were found between the PCRON and NCRON groups in AQP4-ON patients.

Conclusion

Mild COVID-19 is more likely associated with MOG-ON than AQP4-ON. MOG-ON that develops within 6 weeks following a COVID-19 infection may be associated with the COVID-19 infection. AVDs may have a synergistic effect on MOG-ON in patients with COVID-19, which warrants further investigation. COVID-19 related MOG-ON often affects both eyes, and acute visual function damage can be severe, but generally has a good prognosis.

Combined Central and Peripheral Demyelination (CCPD) Associated with MOG Antibodies: Report of Four New Cases and Narrative Review of the Literature

Background/Objectives: Myelin oligodendrocyte glycoprotein (MOG) is exclusively expressed in the central nervous system (CNS) and is found on the outer surface of oligodendrocytes. Antibodies to MOG are associated with CNS demyelination, whereas peripheral nervous system (PNS) demyelination is seldom reported to be related to MOG-IgG. Methods: The database of patients seen in our neurological academic center was searched for MOG-IgG seropositivity and concomitant demyelinating polyneuropathy. For the purpose of the review, in March 2024, we searched for case reports and case series in the following databases: PubMed, Scopus, Cochrane, and ScienceDirect. Inclusion criteria were MOG-IgG seropositivity and demyelinating polyneuropathy. Exclusion criteria were type of publication other than case reports and case series, unconfirmed diagnosis of demyelinating polyneuropathy, and other diseases causing demyelination in either the CNS or PNS. Critical appraisal of the selected case reports and case series was realized by JBI. Results: Four new cases were identified with MOG-IgG and confirmed demyelinating polyneuropathy. This review identified 22 cases that have been published since 2018. Clinical, imaging, neurophysiological, and immunological characteristics, as well as treatment options and outcomes are presented and compared to those of other cases with combined central and peripheral demyelination (CCPD). Conclusions: The pathogenetic mechanism is unclear; thus, different hypotheses are discussed. New case reporting and large cohort studies will help further the exploration of the underlying mechanism and guide more effective therapeutic interventions.

Emergent Management of Central Nervous System Demyelinating Disorders

OBJECTIVE

This article reviews the various conditions that can present with acute and severe central nervous system demyelination, the broad differential diagnosis of these conditions, the most appropriate diagnostic workup, and the acute treatment regimens to be administered to help achieve the best possible patient outcomes.

LATEST DEVELOPMENTS

The discovery of anti-aquaporin 4 (AQP4) antibodies and anti-myelin oligodendrocyte glycoprotein (MOG) antibodies in the past two decades has revolutionized our understanding of acute demyelinating disorders, their evaluation, and their management.

ESSENTIAL POINTS

Demyelinating disorders comprise a large category of neurologic disorders seen by practicing neurologists. In the majority of cases, patients with these conditions do not require care in an intensive care unit. However, certain disorders may cause severe demyelination that necessitates intensive care unit admission because of numerous simultaneous multifocal lesions, tumefactive lesions, or lesions in certain brain locations that lead to acute severe neurologic dysfunction. Intensive care may be necessary for the management and prevention of complications for patients who have severely altered mental status, rapidly progressive neurologic worsening, elevated intracranial pressure, severe cerebral edema, status epilepticus, or respiratory failure.

Myelin Oligodendrocyte Glycoprotein Antibody Disease Optic Neuritis: A Structure-Function Paradox?

BACKGROUND

Myelin oligodendrocyte glycoprotein antibody disease (MOGAD) is a demyelinating disorder that most commonly presents with optic neuritis (ON) and affects children more often than adults. We report 8 pediatric patients with MOG-associated ON and characterize focal optical coherence tomography (OCT) abnormalities over time that help distinguish this condition from the trajectories of other demyelinating disorders. These OCT findings are examined in the context of longitudinal visual function testing.

METHODS

This is a retrospective case series of 8 pediatric patients with MOG-associated ON who were referred for neuro-ophthalmic evaluation. Longitudinal data for demographics, clinical history, physical examination, and OCT obtained in the course of clinical evaluations were collected through retrospective medical record review.

RESULTS

Patients demonstrated acute peripapillary retinal nerve fiber layer (RNFL) thickening in one or both eyes, consistent with optic disc swelling. This was followed by steady patterns of average RNFL thinning, with 9 of 16 eyes reaching significantly low RNFL thickness using OCT platform reference databases ( P < 0.01), accompanied by paradoxical recovery of high-contrast visual acuity (HCVA) in every patient. There was no correlation between HCVA and any OCT measures, although contrast sensitivity (CS) was associated with global thickness, PMB thickness, and nasal/temporal (N/T) ratio, and color vision was associated with PMB thickness. There was a lower global and papillomacular bundle (PMB) thickness ( P < 0.01) in clinically affected eyes compared with unaffected eyes. There was also a significantly higher N:T ratio in clinically affected eyes compared with unaffected eyes in the acute MOG-ON setting ( P = 0.03), but not in the long-term setting.

CONCLUSIONS

MOG shows a pattern of prominent retinal atrophy, as demonstrated by global RNFL thinning, with remarkable preservation of HCVA but remaining deficits in CS and color vision. These tests may be better clinical markers of vision changes secondary to MOG-ON. Of the OCT parameters measured, PMB thickness demonstrated the most consistent correlation between structural and functional measures. Thus, it may be a more sensitive marker of clinically significant retinal atrophy in MOG-ON. The N:T ratio in acute clinically affected MOG-ON eyes in our study was higher than the N:T ratio of neuromyelitis optica (NMO)-ON eyes and similar to the N:T ratio in multiple sclerosis (MS)-ON eyes as presented in the prior literature. Therefore, MOG may share a more similar pathophysiology to MS compared with NMO.

Myelin Oligodendrocyte Glycoprotein-Antibody Associated Disease: An Updated Review of the Clinical Spectrum, Pathogenetic Mechanisms and Therapeutic Management

Clinical syndromes associated with antibodies against myelin oligodendrocyte glycoprotein (MOG) are now recognized as a distinct neurological disease entity, and are gaining increasing attention. The pathogenic mechanisms underlying MOG-antibody disease (MOGAD) remain incompletely understood. Case series, facilitated by registries, and observational studies over the past few years have shed increasing light on the clinical aspects and therapeutic approaches of MOGAD. MOGAD may manifest with a variety of clinical syndromes, including acute disseminated encephalomyelitis (ADEM), autoimmune encephalitis, optic neuritis (ON) and transverse myelitis (TM). MOGAD can be either monophasic or relapsing. This review aims to provide a comprehensive updated description of the clinical spectrum, paraclinical features, and prognosis of MOG-antibody disease, as well as summarize its therapeutic considerations. Randomized clinical trials, standardized diagnostic criteria and treatment guidelines are the steps forward.

Myelin Oligodendrocyte Glycoprotein (MOG) Antibody-Associated Optic Neuritis - A Case Report and Literature Review

Background

Myelin oligodendrocyte glycoprotein (MOG)-IgG-associated optic neuritis (ON) is a new subset of demyelinating optic neuropathy.

Case Report

This study presents a case of a 49-year-old woman with MOG-IgG-positive ON, who reported to the ophthalmic emergency room with decreased visual acuity, retrobulbar pain and red color desaturation in her left eye. Abnormalities in the ophthalmological examination were: decreased Snellen's distance best-corrected visual acuity (DBCVA) to 0.04 in her left eye, slightly elevated optic nerve disc in the left eye confirmed by increased peripapillary retinal nerve fiber layer (RNFL) thickness in SD-OCT, abnormalities in pattern visual evoked potentials in both eyes. The preliminary diagnosis was demyelinating optic neuritis left for observation. However, two weeks after the first symptoms, treatment with intravenous methylprednisolone was initiated due to a decrease in DBCVA to no light perception. Intravenous steroids were followed by oral prednisone and later also by mycophenolate mofetil. The patient experienced slow but gradual improvement. One year after the occurrence of the initial symptoms, DBCVA was 0.5 in the left eye, however partial atrophy of the optic nerve developed, confirmed by macular ganglion cell layer (GCL) thickness and RNFL atrophy in SD-OCT, while visual pathway function improved.

Conclusion

All atypical cases of ON should be primarily considered for cell-based assays. MOG-IgG-positive ON usually responds well to steroid drugs and delaying immunosuppressive treatment may cause irreversible damage to the optic nerve.

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.

Clinical analysis of myelin oligodendrocyte glycoprotein antibody-associated disease in a diverse cohort of children: A single-center observational study

BACKGROUND

Prognostic markers for relapse and neurological disability following the first clinical event in children with myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) remain lacking. We investigated the clinical profiles and early prognostic factors associated with relapsing disease or impaired functional outcome in a large single-center cohort of pediatric MOGAD.

METHODS

We retrospectively analyzed the clinical and paraclinical data and treatment outcomes of children with MOGAD seen at Children's Health in Dallas, Texas from 2009 to 2022. Univariate analyses were used to evaluate factors from initial event associated with relapsing disease course and impaired functional outcome (modified Rankin scale [mRS] >1) at final follow-up.

RESULTS

Our cohort comprised of 87 children of diverse race/ethnicity. Presentation with acute disseminated encephalomyelitis (ADEM) was more frequent in children aged ≤8 years and Caucasian background, whereas presentation with optic neuritis was more common in children aged >8 years and other race/ethnicity. 44.3 % (27/61) had relapsing disease course, of whom 48.0 % had multiple relapses. 30.3 % (23/76) had final mRS >1. Children with abnormal electroencephalogram had reduced relapse risk. Children with ADEM presentation, severe disease, low MOG-IgG titer, and central and systemic inflammation (represented by cerebrospinal fluid pleocytosis and serum leukocytosis, respectively) at onset had higher likelihood of final mRS >1.

CONCLUSION

Abnormal electroencephalogram at the first event was associated with reduced relapse risk while disease severity and peripheral inflammation significantly contributed to final neurological disability. Further studies are needed to validate these findings as early risk factors for disability and relapse and to identify optimal treatment strategies.

Clinical profile and challenges faced in the management of optic neuritis: the Indian scenario

PURPOSE

Optic neuritis (ON) is a relatively common ophthalmic disease that has recently received renewed attention owing to immunological breakthroughs. We studied the profile of patients with ON with special reference to antibody-mediated ON and the challenges faced in its management.

METHODS

Case records of patients with ON presenting to a tertiary eye-care center in South India were analyzed. Data on demographics, presenting visual acuity (VA), clinical features, seropositivity for aquaporin-4 immunoglobulin G (AQP4-IgG) and myelin oligodendrocyte glycoprotein immunoglobulin G (MOG-IgG), details of magnetic resonance imaging (MRI) of orbits and brain, and treatment were collected.

RESULTS

Among 138 cases with acute ON, male: female ratio was 1:2. Isolated ON was present in 41.3% of cases. Antibody testing of sera was performed in 68 patients only due to financial limitations. Among these, 48.5% were MOG-IgG-seropositive, 11.76% were AQP4-IgG-seropositive, and 30.88% samples were double seronegative. Other causes included multiple sclerosis (n = 4), lactational ON (n = 4), tuberculosis (n = 2), invasive perineuritis (n = 2), COVID-19 vaccination (n = 2), and COVID-19 (n = 1). The mean presenting best corrected visual acuity (BCVA) was 1.31 ± 1.16 logMAR (logarithm of the minimum angle of resolution). The mean BCVA at 3 months was 0.167 ± 0.46 logMAR. Only initial VA ≤ 'Counting fingers' (CF) had a significant association with the visual outcome for final VA worse than CF. The steep cost of investigations and treatment posed challenges for many patients in the management of ON.

CONCLUSION

MOG-IgG-associated ON is common in India. Unfortunately, financial constraints delay the diagnosis and timely management of ON, adversely affecting the outcome.

Pediatric acute bilateral optic neuritis: A case report

With the improvement of diagnostic technology, the diagnosis of optic neuritis (ON) has become increasingly accurate. Due to the special characteristics of the pediatric population, there is currently a lack of large-scale studies and related guidelines on pediatric ON. This case report describes the complete diagnosis and treatment process of a 7-year-old male patient with bilateral acute ON, from onset to symptom relief. During the outpatient stage, the patient was suspected of having different types of ON by different departments, but the diagnosis was confirmed through antibody testing after hospitalization. The treatment plan for this case was based on the current plan for adults and the prognosis was better than that of adults with similar characteristics. This suggests that pediatric ON has its own features and requires more case reports and clinical research for further exploration and summary.

Myelin Oligodendrocyte Glycoprotein Antibody-Associated Disease: A Case Report

Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is a newly discovered autoimmune demyelinating disorder. The clinical manifestations of MOGAD are divergent but often characterized by inflammatory central nervous system (CNS) deficits such as optic neuritis, encephalitis, or transverse myelitis that predominantly affect the pediatric population. Despite the distinct features often associated with MOGAD, the disease exhibits a diverse range of clinical manifestations, making timely diagnosis and treatment challenging. In particular, distinguishing MOGAD from multiple sclerosis (MS) is important for adequate treatment and the prevention of relapsing disease. In this report, we present a rare case of MOGAD in a 57-year-old male who initially exhibited symptoms of bilateral optic nerve edema and flame hemorrhage. This led to an initial misdiagnosis of pseudotumor cerebri. Serological analysis at a tertiary care center ultimately led to the diagnosis of MOGAD after multiple visits to the ophthalmologist with worsening vision deficits.

Global trends in research on MOG antibody-associated disease: bibliometrics and visualization analysis

Objective

The purpose of this study was to investigate the current research status, focus areas, and developmental trends in the field of Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) through an analysis of scientific literature.

Methods

The relevant research articles on MOGAD published from 1947 to 2022 were retrieved from the Web of Science database. The quantitative output of MOGAD related research articles, their distribution by country/region, data on collaborative publishing, influential authors, high-yield institutions, keywords, hotspots, and development trends were analyzed. Additionally, visual knowledge maps were generated using VOSviewer and Citespace.

Results

There has been a steady increase in the number of MOGAD related publications indicating that the subject has garnered increasing interest among researchers globally. The United States has been the leading contributor with 496 papers (19.25%), followed by China (244, 9.63%), Japan (183, 7.10%), the United Kingdom (154, 5.98%), and Germany (149, 5.78%). Among these countries, the United Kingdom boasts the highest citation frequency at the rate of 46.49 times per paper. Furthermore, active collaboration in MOGAD related research is observed primarily between the United States and countries such as Canada, Germany, Australia, Italy, the United Kingdom and Japan. Mayo Clinic ranks first in total articles published (109) and frequency of citations per article (77.79). Takahashi Toshiyuki from Tohoku University is the most prolific author, while Multiple Sclerosis and Related Disorders is the most widely read journal in this field. "Disease Phenotype", "Treatment", "Novel Coronavirus Infection and Vaccination", "Immunopathological Mechanisms", "Clinical characteristics of children" and "Prognosis" are the primary keywords clusters in this field. "Novel Coronavirus Infection and Vaccination" and "Immunopathological Mechanisms" are research hotspots and have great development potential.

Conclusion

The past three decades have witnessed a significant expansion of research on MOGAD. The pathogenetic mechanism of MOGAD is poised to be the prominent research focus in this field in the foreseeable future.

Updates in NMOSD and MOGAD Diagnosis and Treatment: A Tale of Two Central Nervous System Autoimmune Inflammatory Disorders

Aquaporin-4-IgG positive neuromyelitis optica spectrum disorder (AQP4+NMOSD) and myelin-oligodendrocyte glycoprotein antibody-associated disease (MOGAD) are antibody-associated diseases targeting astrocytes and oligodendrocytes, respectively. Their recognition as distinct entities has led to each having its own diagnostic criteria that require a combination of clinical, serologic, and MRI features. The therapeutic approach to acute attacks in AQP4+NMOSD and MOGAD is similar. There is now class 1 evidence to support attack-prevention medications for AQP4+NMOSD. MOGAD lacks proven treatments although clinical trials are now underway. In this review, we will outline similarities and differences between AQP4+NMOSD and MOGAD in terms of diagnosis and treatment.

Clinical Features of Patients with Myelin Oligodendrocyte Glycoprotein Antibody-Associated Disease and Isolated Seizure Symptoms

Background

Myelin oligodendrocyte glycoprotein (MOG) antibody-associated encephalitis is a new clinical phenotype of inflammatory demyelinating diseases. Some MOG antibody-positive patients with central nervous system demyelinating events present with isolated seizures. However, there are gaps in the epidemiological knowledge regarding seizures with MOG antibody-associated encephalitis in adults. This study characterized the clinical features and treatment of MOG antibody-positive patients with isolated seizures.

Methods

We reviewed all the patients admitted to Tianjin Huanhu Hospital between Jan. 1st 2017 and Jan. 1st 2022, to screen the MOG antibody-positive patients with isolated seizures, and collected the concerned patients' information regarding epidemiology, clinical presentations, laboratory and radiological characteristics, electroencephalogram (EEG), treatments, and prognoses.

Results

We collected six MOG antibody-positive adult patients who had isolated symptomatic seizures. The mean age of the patients was 33 years (range, 29-40 years), and five (83.3%) were men. All patients presented with motor seizures, five (83.3%) had cognitive dysfunction, and only one (16.7%) had status epilepticus. Five (83.3%) patients had a good response to immunotherapy and antiseizure medications; only one had a sequela. The cerebrospinal fluid or serum anti-MOG antibody test turned negative over time.

Discussion

The most common seizure type in patients with MOG antibody-associated encephalitis with isolated seizures was focal to bilateral tonic-clonic seizures, and most patients had a good prognosis. Adding antiseizure medications were beneficial for MOG antibody-positive patients with seizures. Relapses and sequelae were associated with low-dose, short-time, or delayed therapy, and wide-range demyelinating brain damage.

Systemic inflammation response index is a useful indicator in distinguishing MOGAD from AQP4-IgG-positive NMOSD

Objective

To identify reliable immune-inflammation indicators for distinguishing myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) from anti-aquaporin-4 immunoglobulin G (AQP4-IgG)-positive neuromyelitis optica spectrum disorders (NMOSD). To assess these indicators' predictive significance in MOGAD recurrence.

Methods

This study included 25 MOGAD patients, 60 AQP4-IgG-positive NMOSD patients, and 60 healthy controls (HCs). Age and gender were matched among these three groups. Participant clinical and imaging findings, expanded disability status scale (EDSS) scores, cerebrospinal fluid (CSF) information, and blood cell counts were documented. Subsequently, immune-inflammation indicators were calculated and compared among the MOGAD, AQP4-IgG-positive NMOSD, and HC groups. Furthermore, we employed ROC curve analysis to assess the predictive performance of each indicator and binary logistic regression analysis to assess potential risk factors.

Results

In MOGAD patients, systemic inflammation response index (SIRI), CSF white cell count (WCC), and CSF immunoglobulin A (IgA) levels were significantly higher than in AQP4-IgG-positive NMOSD patients (p = 0.038, p = 0.039, p = 0.021, respectively). The ROC curves showed that SIRI had a sensitivity of 0.68 and a specificity of 0.7 for distinguishing MOGAD from AQP4-IgG-positive NMOSD, with an AUC of 0.692 (95% CI: 0.567-0.818, p = 0.0054). Additionally, compared to HCs, both MOGAD and AQP4-IgG-positive NMOSD patients had higher neutrophils, neutrophil-to-lymphocyte ratio (NLR), SIRI, and systemic immune-inflammation index (SII). Eight (32%) of the 25 MOGAD patients had recurrence within 12 months. We found that the monocyte-to-lymphocyte ratio (MLR, AUC = 0.805, 95% CI = 0.616-0.994, cut-off value = 0.200, sensitivity = 0.750, specificity = 0.882) was an effective predictor of MOGAD recurrence. Binary logistic regression analysis showed that MLR below 0.200 at first admission was the only risk factor for recurrence (p = 0.005, odds ratio =22.5, 95% CI: 2.552-198.376).

Conclusion

Elevated SIRI aids in distinguishing MOGAD from AQP4-IgG-positive NMOSD; lower MLR levels may be linked to the risk of MOGAD recurrence.

Visual outcome measures in pediatric myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD)

BACKGROUND

Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) comprises various age-dependent clinical phenotypes and may be monophasic, multiphasic, or chronic. Optic neuritis (ON) is a common manifestation and frequently appears in combination with other MOGAD phenotypes, particularly in young children. Despite permanent structural damage to the retinal nerve fiber layer (RNFL), children often experience complete visual recovery.

AIMS

To analyze the progression and impact of MOGAD on the visual system of pediatric patients independently of the history of ON.

METHODS

This retrospective study included children who met specific criteria: myelin oligodendrocyte glycoprotein (MOG) immunoglobulin G (IgG) seropositivity, acute presentation of MOGAD, and written general consent. Main outcome measures were global peripapillary retinal nerve fiber layer (pRNFL) thickness, and near and distance visual acuity, analyzed using descriptive statistics.

RESULTS

We identified 10 patients with median age of 7.7 years at first event: 7 patients manifested with acute disseminated encephalomyelitis (ADEM) (with ON 5/7, ADEM only 1/7, with transverse myelitis (TM) 1/7), 2 with isolated ON, and 1 patient with neuromyelitis optica spectrum disorder (NMOSD)-like phenotype with ON. Among ON patients, 5/8 were affected bilaterally, with 3 initially diagnosed with unilateral ON but experiencing subsequent involvement of the fellow eye. None of the patients without previous ON showed a deterioration of visual acuity and, if evaluated, a reduction of the pRNFL.

CONCLUSION

Most pediatric MOGAD-ON patients in our cohort presented with acute vison loss and optic disc edema. All patients achieved complete visual recovery, independent of number of relapses or initial visual loss. The pRNFL thickness decreased for several months and stabilized at reduced levels after 12 months in the absence of further relapses. MOGAD may not have subclinical/'silent' effects on the visual system, as visual acuity and pRNFL were not affected in patients without ON.

Use of Tocilizumab Followed by Rituximab Desensitization on Relapsing Myelin Oligodendrocyte Antibody Disease: A Case Report

Myelin oligodendrocyte antibody disease is a demyelinating disorder that usually presents with a monophasic course. Relapse in this demyelinating disorder is rare, and those who relapse have a weaker response to standard therapy. In this case report, we report a three-year follow-up on a case of a female patient who was diagnosed with myelin oligodendrocyte antibody disease at 21 years old. The patient initially presented with transverse myelitis followed by optic neuritis five months after the onset of transverse myelitis. On relapse, the patient was initially treated with rituximab only to present with type 1 hypersensitivity reaction. Due to the hypersensitivity reaction, the treatment regimen was shifted to tocilizumab, for which she completed a total of five cycles. With tocilizumab treatment, she was noted to have one relapse of symptoms triggered by COVID-19 infection. However, due to tocilizumab-associated alopecia, the patient was shifted to rituximab infusion with desensitization. She then underwent four cycles of rituximab with desensitization, which she tolerated well, and is now in full remission after the fourth cycle of rituximab with no residual deficits. As relapse in myelin oligodendrocyte antibody disease is rare, studies regarding the use of tocilizumab and rituximab as second-line treatment for this disorder are limited. Literature regarding treatment with rituximab infusion with desensitization is even more limited. This case report highlights the potential use of tocilizumab and rituximab in relapsing cases of myelin oligodendrocyte antibody disease, as well as the need for additional literature regarding the use of tocilizumab and rituximab with or without desensitization in relapse in myelin oligodendrocyte antibody disease.

Evidence-based management of optic neuritis

PURPOSE OF REVIEW

Optic neuritis can result from several distinct causes, including multiple sclerosis (MS), neuromyelitis optica spectrum disorder (NMOSD), and myelin oligodendrocyte glycoprotein antibody disease (MOGAD), when not idiopathic. This review discusses evidence-based treatment approaches contingent upon each specific cause of optic neuritis.

RECENT FINDINGS

Current evidence highlights the need for prompt plasmapheresis as adjunct to intravenous methylprednisolone (IVMP) in patients with NMOSD-associated optic neuritis. Recent advances have included a proliferation of novel disease modifying therapies (DMTs) for long-term management of NMOSD and an understanding of how existing therapeutic options can be leveraged to optimally treat MOGAD.

SUMMARY

In acute idiopathic or MS-associated optic neuritis, IVMP hastens visual recovery, though it does not substantially affect final visual outcomes. IVMP and adjunctive plasmapheresis are beneficial in the treatment of NMOSD-associated optic neuritis, with a shorter time-to-treatment associated with a higher likelihood of recovery. The natural history of untreated MOGAD-associated optic neuritis is unclear but treatment with IVMP is near-universal given phenotypic similarities with NMOSD. Long-term immunosuppressive therapy is warranted in patients with NMOSD as well as in patients with MOGAD with poor visual recovery or recurrent attacks.

Monoclonal antibodies in neuro-ophthalmology

Neuro-ophthalmologic diseases include a broad range of disorders affecting the afferent and efferent visual pathways. Recently, monoclonal antibody (mAb) therapies have emerged as a promising targeted approach in the management of several of these complex conditions. Here, we describe the mechanism-specific applications and advancements in neuro-ophthalmologic mAb therapies. The application of mAbs in neuro-ophthalmologic diseases highlights our increasing understanding of disease-specific mechanisms in autoimmune conditions such as neuromyelitis optica, thyroid eye disease, and myasthenia gravis. Due to the specificity of mAb therapies, applications in neuro-ophthalmologic diseases have yielded exceptional clinical outcomes, including both reduced rate of relapse and progression to disability, visual function preservation, and quality of life improvement. These advancements have not only expanded the range of treatable neuro-ophthalmologic diseases but also reduced adverse events and increased the response rate to treatment. Further research into neuro-ophthalmologic disease mechanisms will provide accurate and specific targeting of important disease mediators through applications of future mAbs. As our understanding of these diseases and the relevant therapeutic targets evolve, we will continue to build on our understanding of how mAbs interfere with disease pathogenesis, and how these changes improve clinical outcomes and quality of life for patients.

Antibodies to neural cell surface and synaptic proteins in paraneoplastic neurologic syndromes

Among patients with paraneoplastic neurologic syndromes (PNS), emphasis has historically been placed on neural antibodies against intracellular proteins that have a strong association with malignancy. Because of the intracellular location of their antigenic targets, these antibodies are typically considered to be non-pathogenic surrogate markers of immune cell-mediated neural injury. Unfortunately, patients with these antibodies often have suboptimal response to immunotherapy and poor prognosis. Over the last two decades, however, dramatic advancements have been made in the discovery and clinical characterization of neural antibodies against extracellular targets. These antibodies are generally considered to be pathogenic, given their potential to directly alter antigen structure or function, and patients with these antibodies often respond favorably to prompt immunotherapy. These antibodies also associate with tumors and may thus occur as PNS, albeit more variably than neural antibodies against intracellular targets. The updated 2021 PNS diagnostic criteria, which classifies antibodies as high-risk, intermediate-risk, or lower-risk for an associated cancer, better clarifies how neural antibodies against extracellular targets relate to PNS. Using this recently created framework, the clinical presentations, ancillary test findings, oncologic associations, and treatment responses of syndromes associated with these antibodies are discussed.

Clinical Usefulness of a Cell-based Assay for Detecting Myelin Oligodendrocyte Glycoprotein Antibodies in Central Nervous System Inflammatory Disorders

Background

The clinical implications of myelin oligodendrocyte glycoprotein autoantibodies (MOG-Abs) are increasing. Establishing MOG-Ab assays is essential for effectively treating patients with MOG-Abs. We established an in-house cell-based assay (CBA) to detect MOG-Abs to identify correlations with patients' clinical characteristics.

Methods

We established the CBA using HEK 293 cells transiently overexpressing full-length human MOG, tested it against 166 samples from a multicenter registry of central nervous system (CNS) inflammatory disorders, and compared the results with those of the Oxford MOG-Ab-based CBA and a commercial MOG-Ab CBA kit. We recruited additional patients with MOG-Abs and compared the clinical characteristics of MOG-Ab-associated disease (MOGAD) with those of neuromyelitis optica spectrum disorder (NMOSD).

Results

Of 166 samples tested, 10 tested positive for MOG-Abs, with optic neuritis (ON) being the most common manifestation (4/15, 26.7%). The in-house and Oxford MOG-Ab CBAs agreed for 164/166 (98.8%) samples (κ=0.883, P<0.001); two patients (2/166, 1.2%) were only positive in our in-house CBA, and the CBA scores of the two laboratories correlated well (r=0.663, P<0.001). The commercial MOG-Ab CBA kit showed one false-negative and three false-positive results. The clinical presentation at disease onset differed between MOGAD and NMOSD; ON was the most frequent manifestation in MOGAD, and transverse myelitis was most frequent in NMOSD.

Conclusions

The in-house CBA for MOG-Abs demonstrated reliable results and can potentially be used to evaluate CNS inflammatory disorders. A comprehensive, long-term study with a large patient population would clarify the clinical significance of MOG-Abs.

A longitudinal analysis of brain volume changes in myelin oligodendrocyte glycoprotein antibody-associated disease

BACKGROUND AND PURPOSE

Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is a relapsing demyelinating condition. There are several cross-sectional studies showing evidence of brain atrophy in people with MOGAD (pwMOGAD), but longitudinal brain volumetric assessment is still an unmet need. Current recommendations do not include monitoring with MRI and assume distinct attacks. Evidence of ongoing axon loss will have diagnostic and therapeutic implications. In this study, we assessed brain volume changes in pwMOGAD over a mean follow-up period of 2 years and compared this to changes in people with multiple sclerosis (pwMS).

METHODS

This is a retrospective single-center study over a 7-year period from 2014 to 2021. MRI brain scans at the time of diagnosis and follow-up in remission were collected from 14 Caucasian pwMOGAD, confirmed by serum myelin oligodendrocyte glycoprotein immunoglobulin G antibody presence, detected by live cell-based assays. Total brain volume (TBV), white matter (WM), gray matter (GM), and demyelinating lesion volumes were assessed automatically using the Statistical Parametric Mapping and FMRIB automated segmentation tools. MRI brain scans at diagnosis and follow-up on remission were collected from 32-matched pwMS for comparison. Statistical analysis was done using analysis of variance.

RESULTS

There is evidence of TBV loss, affecting particularly GM, over an approximately 2-year follow-up period in pwMOGAD (p < .05), comparable to pwMS. WM and lesion volume change over the same period were not statistically significant (p > .1).

CONCLUSION

We found evidence of loss of GM and TBV over time  in pwMOGAD, similar to pwMS, although the WM and lesion volumes were unchanged.

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.

Dramatic Response to Anti-IL-6 Receptor Therapy in Children With Life-Threatening Myelin Oligodendrocyte Glycoprotein-Associated Disease

OBJECTIVES

Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is an immune-mediated neuroinflammatory disorder leading to demyelination of the CNS. Interleukin (IL)-6 receptor blockade is under study in relapsing MOGAD as a preventative strategy, but little is known about the role of such treatment for acute MOGAD attacks.

METHODS

We discuss the cases of a 7-year-old boy and a 15-year-old adolescent boy with severe acute CNS demyelination and malignant cerebral edema with early brain herniation associated with clearly positive serum titers of MOG-IgG, whose symptoms were incompletely responsive to standard acute therapies (high-dose steroids, IV immunoglobulins (IVIGs), and therapeutic plasma exchange).

RESULTS

Both boys improved quickly with IL-6 receptor inhibition, administered as tocilizumab. Both patients have experienced remarkable neurologic recovery.

DISCUSSION

We propose that IL-6 receptor therapies might also be considered in acute severe life-threatening presentations of MOGAD.

Clinical spectrum of myelin oligodendrocyte glycoprotein antibody-associated disease in Brazil: a single-center experience

BACKGROUND

 Anti-myelin oligodendrocyte glycoprotein (anti-MOG) antibody-associated disease (MOGAD) is an immune-mediated neurological disorder with a broad spectrum of clinical presentation that is often difficult to distinguish from other demyelinating diseases, such as multiple sclerosis and neuromyelitis optica spectrum disorder.

OBJECTIVE

 To describe the clinical and paraclinical characteristics of MOGAD in a Brazilian tertiary center.

METHODS

 We retrospectively reviewed the records of adult and pediatric patients who tested positive for anti-MOG antibodies and presented with clinical and radiological diseases compatible with MOGAD.

RESULTS

 Forty-one patients (10 children) were included: 56% female, 58% Caucasian, mean age at onset 31 years (range 6-64), with a mean disease duration of 59.6 months (range 1-264 months). The most frequent onset presentation was optic neuritis (68%), acute disseminated encephalomyelitis (ADEM, 12%), and myelitis (10%). A monophasic disease course was observed in 49%. EDSS median was 2.1 at the last visit. Most patients (83%) were under continuous immunosuppressive treatment. Azathioprine was the first-line treatment in 59%. In all ADEM cases, conus, and root involvement was radiologically observed on MRI.

CONCLUSION

 Brazilian MOGAD patients presented with a similar spectrum of previously reported MOGAD phenotypes. Conus and spinal root involvement seems to be frequently present in MOGAD-ADEM and could serve as radiologic characteristics of this clinical entity.

Epidemiology of myelin oligodendrocyte glycoprotein antibody-associated disease: a review of prevalence and incidence worldwide

Myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD) is an inflammatory demyelinating disease of the central nervous system (CNS) with the presence of conformation-sensitive antibodies against MOG. The spectrum of MOGAD includes monophasic/relapsing optic neuritis, myelitis, neuromyelitis optica spectrum disorder (NMOSD) phenotype without aquaporin 4 (AQP4) antibodies, acute/multiphasic demyelinating encephalomyelitis (ADEM/MDEM)-like presentation, and brainstem and cerebral cortical encephalitis. There is no apparent female preponderance in MOGAD, and MOGAD can onset in all age groups (age at onset is approximately 30 years on average, and approximately 30% of cases are in the pediatric age group). While prevalence and incidence data have been available for AQP4+ NMOSD globally, such data are only beginning to accumulate for MOGAD. We reviewed the currently available data from population-based MOGAD studies conducted around the world: three studies in Europe, three in Asia, and one joint study in the Americas. The prevalence of MOGAD is approximately 1.3-2.5/100,000, and the annual incidence is approximately 3.4-4.8 per million. Among White people, the prevalence of MOGAD appears to be slightly higher than that of AQP4+ NMOSD. No obvious latitude gradient was observed in the Japanese nationwide survey. The data available so far showed no obvious racial preponderance or strong HLA associations in MOGAD. However, precedent infection was reported in approximately 20-40% of MOGAD cases, and this is worthy of further investigation. Co-existing autoimmune disorders are less common in MOGAD than in AQP4+ NMOSD, but NMDAR antibodies may occasionally be positive in patients with MOGAD. More population-based studies in different populations and regions are useful to further inform the epidemiology of this disease.

Role of serostatus in pediatric neuromyelitis optica spectrum disorders: A nationwide multicentric study

BACKGROUND

Neuromyelitis optica spectrum disorders (NMOSD) are immune-mediated inflammatory disorders of the central nervous system (CNS) mostly presenting as optic neuritis and acute myelitis. NMOSD can be associated with seropositivity for aquaporin 4 antibody (AQP4 IgG), myelin oligodendrocyte glycoprotein antibody (MOG IgG), or can be seronegative for both. In this study, we retrospectively examined our seropositive and seronegative pediatric NMOSD patients.

METHOD

Data were collected from all participating centres nationwide. Patients diagnosed with NMOSD were divided into three subgroups according to serology: AQP4 IgG NMOSD, MOG IgG NMOSD, and double seronegative (DN) NMOSD. Patients with at least six months of follow-up were compared statistically.

RESULTS

The study included 45 patients, 29 female and 16 male (ratio:1.8), mean age 15.16 ± 4.93 (range 5.5-27) years. Age at onset, clinical manifestations, and cerebrospinal fluid findings were similar between AQP4 IgG NMOSD (n = 17), MOG IgG NMOSD (n = 10), and DN NMOSD (n = 18) groups. A polyphasic course was more frequent in the AQP4 IgG and MOG IgG NMOSD groups than DN NMOSD (p = 0.007). The annualized relapse rate and rate of disability were similar between groups. Most common types of disability were related to optic pathway and spinal cord involvement. Rituximab in AQP4 IgG NMOSD, intravenous immunoglobulin in MOG IgG NMOSD, and azathioprine in DN NMOSD were usually preferred for maintenance treatment.

CONCLUSION

In our series with a considerable number of double seronegatives, the three major serological groups of NMOSD were indistinguishable based on clinical and laboratory findings at initial presentation. Their outcome is similar in terms of disability, but seropositive patients should be more closely followed-up for relapses.

Clinical features of MOGAD with brainstem involvement in the initial attack versus NMOSD and MS

OBJECTIVE

To assess the characteristics of Myelin oligodendrocyte glycoprotein (MOG) antibody-associated disorder (MOGAD) with brainstem involvement in the first event (BSIFE) and make comparisons with aquaporin-4-IgG seropositive neuromyelitis optica spectrum disorder (AQP4-IgG-NMOSD) and multiple sclerosis (MS).

METHODS

From 2017 to 2022, this study identified MOG-IgG-positive patients with brainstem or both brainstem and cerebellum lesions in the first episode. As a comparison group, AQP4-IgG-NMOSD (n = 30) and MS (n = 30) patients with BSIFE were enroled.

RESULTS

Thirty-five patients (35/146, 24.0%) were the BSIFE of MOGAD. Isolated brainstem episodes occurred in 9 of the 35 (25.7%) MOGAD patients, which was similar to MS (7/30, 23.3%) but was lower than AQP4-IgG-NMOSD (17/30, 56.7%, P = 0.011). Pons (21/35, 60.0%), medulla oblongata (20/35, 57.1%) and middle cerebellar peduncle (MCP, 19/35, 54.3%) were the most frequently affected areas. Intractable nausea (n = 7), vomiting (n = 8) and hiccups (n = 2) happened in MOGAD patients, but EDSS of MOGAD was lower than AQP4-IgG-NMOSD (P = 0.001) at the last follow-up. MOGAD patients with or without BSIFE did not significantly differ in terms of the ARR (P = 0.102), mRS (P = 0.823), or EDSS (P = 0.598) at the most recent follow-up. Specific oligoclonal bands appeared in MOGAD (13/33, 39.4%) and AQP4-IgG-NMOSD (7/24, 29.2%) in addition to MS (20/30, 66.7%). Fourteen MOGAD patients (40.0%) experienced relapse in this study. When the brainstem was involved in the first attack, there was an increased likelihood of a second attack occurring at the same location (OR=12.22, 95%CI 2.79 to 53.59, P = 0.001). If the first and second events were both in the brainstem, the third event was likely to occur at the same location (OR=66.00, 95%CI 3.47 to 1254.57, P = 0.005). Four patients experienced relapses after the MOG-IgG turned negative.

CONCLUSION

BSIFE occurred in 24.0% of MOGAD. Pons, medulla oblongata and MCP were the most frequently involved regions. Intractable nausea, vomiting and hiccups occurred in MOGAD and AQP4-IgG-NMOSD, but not MS. The prognosis of MOGAD was better than AQP4-IgG-NMOSD. In contrast to MS, BSIFE may not indicate a worse prognosis for MOGAD. When patients with BSIFE, MOGAD tent to reoccur in the brainstem. Four of the 14 recurring MOGAD patients relapsed after the MOG-IgG test turned negative.

Intravenous immunoglobulin treatment for acute attacks in myelin oligodendrocyte glycoprotein antibody disease

BACKGROUND

The potential therapeutic benefit of intravenous immunoglobulins (IVIGs) for acute attacks of myelin oligodendrocyte glycoprotein antibody disease (MOGAD) is unknown.

OBJECTIVE

The objective was to describe the outcomes of IVIG treatment for acute MOGAD attacks.

METHODS

A retrospective observational study involving seven tertiary neuroimmunology centers. Data collection included patients' demographics, Expanded Disability Status Scale (EDSS), and visual acuity (VA) before the attack, at the nadir of the attack before IVIG treatment, and at follow-up visits ⩾3 months after treatment.

RESULTS

Thirty-nine patients were included, of which 21 (53.8%) were female. The median age was 23 years (range 5-74 years), and the median disease duration was 4 months (range 0-93 months). The most common type of attack treated with IVIG was isolated optic neuritis (ON) (unilateral n = 14, bilateral n = 5, associated with transverse myelitis (TM), n = 1), followed by acute disseminated encephalomyelitis (ADEM) (n = 8), multifocal (n = 7), TM (n = 3), brainstem (n = 1), and other encephalitis (n = 1). A significant improvement in both the EDSS and VA measures was observed at follow-up compared to the time of IVIG treatment initiation (p < 0.0001 for both outcome measures).

CONCLUSION

IVIG may be an effective treatment option for acute MOGAD attacks. Further prospective studies are warranted to validate our results.

The neuro-ophthalmological manifestations of NMOSD and MOGAD-a comprehensive review

Optic neuritis (ON) is one of the most frequently seen neuro-ophthalmic causes of vision loss worldwide. Typical ON is often idiopathic or seen in patients with multiple sclerosis, which is well described in the landmark clinical trial, the Optic Neuritis Treatment Trial (ONTT). However, since the completion of the ONTT, there has been the discovery of aquaporin-4 (AQP4) and myelin oligodendrocyte glycoprotein (MOG) antibodies, which are biomarkers for neuromyelitis optica spectrum disorder (NMOSD) and MOG antibody-associated disease (MOGAD), respectively. These disorders are associated with atypical ON that was not well characterised in the ONTT. The severity, rate of recurrence and overall outcome differs in these two entities requiring prompt and accurate diagnosis and management. This review will summarise the characteristic neuro-ophthalmological signs in NMOSD and MOGAD, serological markers and radiographic findings, as well as acute and long-term therapies used for these disorders.

A Case of Myelin Oligodendrocyte Glycoprotein Antibody-Associated Optic Neuritis Responsive to Intravenous Immunoglobulin (IVIG) Therapy in a Pediatric Patient

We present a case of an eight-year-old boy who presented with complaints of headache, blurry vision, and eye pain. Ophthalmological exams and magnetic resonance imaging confirmed the presence of optic neuritis. Initial cerebrospinal fluid analysis was negative for all antibodies (Abs) associated with optic neuritis and other acute demyelinating syndromes, including anti-myelin oligodendrocyte glycoprotein Ab (anti-MOG-Ab). The child was treated with a course of pulse methylprednisolone therapy for five days, with significant improvement in his symptoms. However, the child went on to have a recurrent episode of optic neuritis one month after his initial presentation. Hence, investigations targeting immunological biomarkers were repeated and turned out to be positive for anti-MOG-Abs with elevated titers. The child was diagnosed with MOG-Ab-associated optic neuritis presenting as chronic relapsing inflammatory optic neuropathy (CRION). He was then started on maintenance intravenous immunoglobulin (IVIG) therapy as a disease-modifying therapy, following which he has not had any further relapses over two years.

High level of agreement in a fixed vs. live cell-based assay for antibodies to myelin oligodendrocyte glycoprotein in a real-world clinical laboratory setting

Introduction

As recognition of myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease becomes more widespread, the importance of appropriately ordering and interpreting diagnostic testing for this antibody increases. Several assays are commercially available for MOG testing, and based on a few small studies with very few discrepant results, some have suggested that live cell-based assays (CBA) are superior to fixed CBA for clinical MOG antibody testing. We aimed to determine the real-world agreement between a fixed and live CBA for MOG using two of the most commonly available commercial testing platforms.

Methods

We compared paired clinical samples tested at two national clinical reference laboratories and determined the real-world agreement between the fixed CBA and live CBA.

Results

Of 322 paired samples tested on both platforms, 53 were positive and 246 were negative by both methodologies (agreement 92.9%, Cohen's kappa 0.78, [0.69-0.86]). Spearman correlation coefficient was 0.80 (p < 0.0001). Of the discrepant results, only 1 of 14 results positive by the live CBA had a titer greater than 1:100, and only 1 of 9 results positive by the fixed CBA had a titer of greater than 1:80. Lower titers on the fixed CBA correlate to higher titers on the live CBA.

Conclusion

Overall, there is excellent agreement between fixed and live CBA for MOG antibody testing in a real-world clinical laboratory setting. Clinicians should be aware of which method they use to assess any given patient, as titers are comparable, but not identical between the assays.

Clinical characteristics of myelin oligodendrocyte glycoprotein antibody-associated disease according to their epitopes

Background

The detection of myelin oligodendrocyte glycoprotein autoantibodies (MOG-Ab) is essential for the diagnosis of MOG-Ab-associated disease (MOGAD). The clinical implications of different epitopes recognized by MOG-Ab are largely unknown. In this study, we established an in-house cell-based immunoassay for detecting MOG-Ab epitopes and examined the clinical characteristics of patients with MOG-Ab according to their epitopes.

Methods

We conducted a retrospective review of patients with MOG-Ab-associated disease (MOGAD) in our single center registry, and collected serum samples from enrolled patients. Human MOG variants were generated to detect epitopes recognized by MOG-Ab. The differences in clinical characteristics according to the presence of reactivity to MOG Proline42 (P42) were evaluated.

Results

Fifty five patients with MOGAD were enrolled. Optic neuritis was the most common presenting syndrome. The P42 position of MOG was a major epitope of MOG-Ab. The patients with a monophasic clinical course and childhood-onset patients were only observed in the group that showed reactivity to the P42 epitope.

Conclusion

We developed an in-house cell-based immunoassay to analyze the epitopes of MOG-Ab. The P42 position of MOG is the primary target of MOG-Ab in Korean patients with MOGAD. Further studies are needed to determine the predictive value of MOG-Ab and its epitopes.

Novel index, neutrophil percentage (%) is a useful marker for disease activity in MOG antibody-associated disease

BACKGROUND

Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is a CNS autoimmune disease affecting the brain, spinal cord, and optic nerve. The neutrophil-to-lymphocyte ratio (NLR) is related to autoimmune disease activity. However, the clinical implication of index ratios such as the NLR is unclear in patients with MOGAD.

OBJECTIVES

We investigated the relationship between index ratios such as the NLR and disease activity and disability to discover the index that best correlates with an attack in MOGAD.

METHODS

Using a CNS demyelinating disease cohort, we reviewed 39 patients with MOGAD (age 37.4 ± 12.0 years; F:M = 20:19) who had 390 blood samples available for cell count analysis. We calculated the NLR, eosinophil-to-lymphocyte-ratio (ELR), platelet-to-lymphocyte-ratio (PLR), monocyte-to-lymphocyte ratio (MLR), basophil-to-lymphocyte ratio (BLR), and neutrophil percentage (N%) [neutrophil count (/mm³) / WBC (/mm³) x 100 (%)]. We investigated the associations between each index ratio and disease activity and disability using the receiver operating characteristic (ROC) curve, machine learning program (kNN algorithm), and generalized estimating equations (GEE) analysis.

RESULTS

In patients with MOGAD, the NLR, PLR, and N% were higher and ELR was lower during an attack than in remission (all p<0.001). The areas under the ROC curve for the NLR, ELR, PLR, and N% were 0.68, 0.69, 0.61, and 0.68, respectively, with the highest sensitivity of 76.0% in the ELR and the highest specificity of 76.3% in the N%. The classification accuracy scores of the kNN machine learning algorithm were 71% for the NLR, 62% for the ELR, 63% for the PLR, and 72% for the N%. In the GEE analysis of attack samples, both the NLR and treatment-naive had positive associations with the Expanded Disability Status Scale (EDSS) score (β=0.137, p = 0.008 and β=1.142, p = 0.003, respectively), and the PLR was negatively associated with the EDSS score (β=-0.004, p = 0.022).

DISCUSSION

Our study suggests that the novel index, neutrophil% is the simplest and the most useful marker to differentiate between attack and remission and shows comparable reliability with NLR in MOGAD. Moreover, the NLR and PLR could be used as supportive biomarkers for disease disability during an attack in patients with MOGAD.

Clinical course, imaging, and pathological features of 45 adult and pediatric cases of myelin oligodendrocyte glycoprotein antibody-associated disease

BACKGROUND

Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is a recently described neuroinflammatory demyelinating disease.

OBJECTIVE

To better understand the clinical spectrum, risk factors and outcomes in MOGAD.

METHODS

Retrospective cohort study including all subjects harboring anti-MOG antibodies identified in major academic hospitals across the province of Quebec.

RESULTS

We identified 45 MOGAD cases. The minimal estimated point-prevalence was 0.52/100 000 in Quebec. Median age at presentation was 32 years (range 1-71) with equal sex ratio. Most frequent ethnic groups were Caucasians and Asians. The most frequent clinical manifestations at onset were optic neuritis (ON), affecting 56% of adults, and acute disseminated encephalomyelitis (ADEM), affecting 33% of children. First MRI was abnormal in 84% of cases. Most CSF samples showed pleocytosis without oligoclonal bands. Two brain biopsies revealed lipid-laden macrophages and reactive astrocytes. Despite steroids, only 38% had fully recovered at 4 weeks after onset. Half of pediatric and two thirds of adult-onset MOGAD subjects experienced relapses. At last follow-up, 69% showed residual deficits, which were moderate to severe in 17% of adults.

CONCLUSION

MOGAD has heterogeneous disease course, and it is not a benign disease for a substantial proportion of adults. Best disease-modifying therapies remain to be determined.

Clinical characteristics and prognosis of optic neuritis in Taiwan - a hospital-based cohort study

BACKGROUND

Optic neuritis (ON) is an inflammatory disease of optic nerve. The distinct etiologies of ON significantly influence its clinical manifestation, neuroimaging findings, and visual outcomes. However, the clinical characteristics might be influenced by the racial differences. The purpose of this study is to investigate the clinical characteristics of various types of ON at a Taiwanese tertiary center.

METHODS

This cohort study analyzed 163 patients who received treatment and continued following-up for ON between 2015 and 2022. We selected patients who had been tested for anti-aquaporin-4 antibody (AQP4-Ab) and anti-myelin oligodendrocyte glycoprotein antibody (MOG-Ab). The participants were classified into four groups on the basis of their etiologies, specifically (1) multiple sclerosis (MS)-related, (2) AQP4-Ab-positive, (3) MOG-Ab-positive, or (4) idiopathic ON. The researchers recorded the patients' clinical characteristics, treatment course, magnetic resonance imaging and optical coherence tomography (OCT) findings, and visual outcomes.

RESULTS

MOG-Ab-positive group had higher percentages of disk swelling and pain with eye movement. Long optic nerve and perineural enhancement are the hallmarks of MOG-Ab-related ON. The ON relapse rate was higher in AQP4-Ab-positive group. Although members of AQP4-Ab-positive group received immediate steroid pulse therapy, these patients experienced the worst visual outcomes. Moreover, a thinner retinal nerve fiber layer (RNFL) was noted in AQP4-Ab-positive group. MS group had a higher incidence of extra-optic nerve lesions. Multivariate regression identified pretreatment visual acuity and RNFL thickness as the important factors affecting visual outcomes.

CONCLUSIONS

This cohort study identified the clinical features of different types of ON. Patients with AQP4-Ab-positive ON had poorer visual outcomes, which may be attributed to multiple relapses and profound nerve damage, as revealed by OCT findings. Patients with MOG-Ab-positive ON displayed long optic nerve enhancement but had more favorable prognoses. Thus, antibody-based classification facilitates treatment and prognosis in ON.