MOG-IgG in NMO and related disorders: a multicenter study of 50 patients. Part 2: Epidemiology, clinical presentation, radiological and laboratory features, treatment responses, and long-term outcome

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

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

Poor Visual Outcome After First Attack in a Cohort of Patients With Myelin Oligodendrocyte Glycoprotein-Related Optic Neuritis

BACKGROUND

Myelin oligodendrocyte glycoprotein-associated optic neuritis (MOG-ON) is typically a highly treatable condition that responds quickly to treatment with high doses of corticosteroids. We reviewed the cohort of patients with MOG-ON to identify patients who had poor visual outcome after the first attack despite rapid initiation of treatment.

METHODS

Records of all patients diagnosed with MOG-ON seen in a tertiary neuro-ophthalmology practice were reviewed to identify and describe those with poor visual recovery (final visual acuity of 20/200 or worse in at least one eye) after the first attack despite initiation of treatment within 1 week of symptoms onset.

RESULTS

Two patients of 36 fulfilled inclusion criteria: both had bilateral severe optic neuritis at presentation, and both were seen within 7 days of symptoms onset and treated immediately with pulse doses of intravenous corticosteroids followed by very-slow oral taper. Plasma exchange (PLEX) was performed 2 weeks after symptoms onset in both patients because of poor response to steroids, followed by monthly intravenous immunoglobulin infusions. Despite the use of all available treatment modalities, final visual outcome was poor in both patients. In both patients, there was enhancement of intracanalicular portion of optic nerve in the worse-seeing eye.

CONCLUSIONS

In this cohort of patients with MOG-ON, 2 (5.6%) had very poor visual outcome after the first attack despite immediate initiation of treatment with pulse doses of corticosteroids and subsequent treatment with PLEX. These cases highlight that despite immediate initiation and escalation of treatment, some patients with MOG-ON can have very poor visual outcomes after the initial attack that may be because of the involvement of the intracanalicular portion of the optic nerves.

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.

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.

Characteristics of recurrence in area postrema-onset NMO spectrum disorder - a retrospective cohort study

BACKGROUND

Neuromyelitis Optica Spectrum Disorder (NMOSD) is an inflammatory autoimmune disease with high risk of recurrence and disability, the treatment goal is a recurrence free state. Area postrema (AP) is one of the most common involved area of NMOSD, which may have a particular significance in the pathogenesis of NMOSD and clinical heterogeneity. Our study is to investigate the clinical and recurrent characteristics AP onset NMOSD patients.

METHODS

A retrospective study was done in a cohort of 166 AQP4-IgG seropositive NMOSD patients which were identified by the 2015 IPND criteria. The patients were divided into AP onset (APO-NMOSD) group and non-AP onset (NAPO-NMOSD) group based on the initial episode location. Clinical features and recurrence differences of two groups were compared.

RESULTS

The APO-NMOSD group and NAPO-NMOSD group had a population ratio of 24:142. APO-NMOSD patients were younger (34.6y VS 42.3y, P = 0.013), had lower EDSS at first episode (0.7 VS 4.2, p = 0.028) and last follow up (1.9 VS 3.3, p = 0.001), more likely to have multi-core lesions at the first attack (33.3% VS 9.2%, P = 0.001). Also, they had a higher annual recurrence rate (0.4 ± 0.28 VS 0.19 ± 0.25, P = 0.012). In natural course NMOSD patients without immunotherapy, APO-NMSOD had a shorter time of first relapse (P < 0.001) and higher annual recurrence rate (0.31 ± 0.22 VS 0.16 ± 0.26, P = 0.038) than NAPO-NMOSD. APO-NMOSD group also have a higher risk of having the first relapsing compared to optic neuritis onset-NMOSD (HR 2.641, 95% CI 1.427-4.887, p = 0.002) and myelitis onset-NMOSD group (HR 3.593, 95% CI 1.736-7.438, p = 0.001). Compared to NAPO-NMOSD, APO-NMOSD has a higher likelihood of brainstem recurrence (28.6% vs. 4.7%, p<0.001) during the first recurrence, while NAPO-NMOSD is more susceptible to optic nerve involvement (10.7% vs. 41.1%, p = 0.01).

CONCLUSION

AQP4-IgG seropositive NMOSD patients with AP onset are youngers and have higher risk of recurrence. Clinicians should pay attention to AP damage in NMOSD, as it indicates a potential risk of recurrence.

TRIAL REGISTRATION

Retrospectively registered.

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.

Oral corticosteroid dosage and taper duration at onset in myelin oligodendrocyte glycoprotein antibody-associated disease influences time to first relapse

BACKGROUND

We sought to identify an optimal oral corticosteroid regimen at the onset of myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD), which would delay time to first relapse while minimising cumulative corticosteroid exposure.

METHODS

In a retrospective multicentre cohort study, Cox proportional hazards models examined the relationship between corticosteroid course as a time-varying covariate and time to first relapse. Simon-Makuch and Kaplan-Meier plots identified an optimal dosing strategy.

RESULTS

We evaluated 109 patients (62 female, 57%; 41 paediatric, 38%; median age at onset 26 years, (IQR 8-38); median follow-up 6.2 years (IQR 2.6-9.6)). 76/109 (70%) experienced a relapse (median time to first relapse 13.7 months; 95% CI 8.2 to 37.9). In a multivariable model, higher doses of oral prednisone delayed time to first relapse with an effect estimate of 3.7% (95% CI 0.8% to 6.6%; p=0.014) reduced hazard of relapse for every 1 mg/day dose increment. There was evidence of reduced hazard of relapse for patients dosed ≥12.5 mg/day (HR 0.21, 95% CI 0.07 to 0.6; p=0.0036), corresponding to a 79% reduction in relapse risk. There was evidence of reduced hazard of relapse for those dosed ≥12.5 mg/day for at least 3 months (HR 0.12, 95% CI 0.03 to 0.44; p=0.0012), corresponding to an 88% reduction in relapse risk compared with those never treated in this range. No patient with this recommended dosing at onset experienced a Common Terminology Criteria for Adverse Events grade >3 adverse effect.

CONCLUSIONS

The optimal dose of 12.5 mg of prednisone daily in adults (0.16 mg/kg/day for children) for a minimum of 3 months at the onset of MOGAD delays time to first relapse.

The MOG antibody non-P42 epitope is predictive of a relapsing course in MOG antibody-associated disease

BACKGROUND

Myelin oligodendrocyte glycoprotein (MOG) IgG seropositivity is a prerequisite for MOG antibody-associated disease (MOGAD) diagnosis. While a significant proportion of patients experience a relapsing disease, there is currently no biomarker predictive of disease course. We aim to determine whether MOG-IgG epitopes can predict a relapsing course in MOGAD patients.

METHODS

MOG-IgG-seropositive confirmed adult MOGAD patients were included (n=202). Serum MOG-IgG and epitope binding were determined by validated flow cytometry live cell-based assays. Associations between epitopes, disease course, clinical phenotype, Expanded Disability Status Scale and Visual Functional System Score at onset and last review were evaluated.

RESULTS

Of 202 MOGAD patients, 150 (74%) patients had MOG-IgG that recognised the immunodominant proline42 (P42) epitope and 115 (57%) recognised histidine103/serine104 (H103/S104). Fifty-two (26%) patients had non-P42 MOG-IgG and showed an increased risk of a relapsing course (HR 1.7; 95% CI 1.15 to 2.60, p=0.009). Relapse-freedom was shorter in patients with non-P42 MOG-IgG (p=0.0079). Non-P42 MOG-IgG epitope status remained unchanged from onset throughout the disease course and was a strong predictor of a relapsing course in patients with unilateral optic neuritis (HR 2.7, 95% CI 1.06 to 6.98, p=0.038), with high specificity (95%, 95% CI 77% to 100%) and positive predictive value (85%, 95% CI 45% to 98%).

CONCLUSIONS

Non-P42 MOG-IgG predicts a relapsing course in a significant subgroup of MOGAD patients. Patients with unilateral optic neuritis, the most frequent MOGAD phenotype, can reliably be tested at onset, regardless of age and sex. Early detection and specialised management in these patients could minimise disability and improve long-term outcomes.

Classification of Myelin Oligodendrocyte Glycoprotein Antibody-Related Disease and Its Mimicking Acute Demyelinating Syndromes in Children Using MRI-Based Radiomics: From Lesion to Subject

RATIONALE AND OBJECTIVES

To develop MRI-based radiomics models from the lesion level to the subject level and assess their value for differentiating myelin oligodendrocyte glycoprotein antibody-related disease (MOGAD) from non-MOGAD acute demyelinating syndromes in pediatrics.

MATERIALS AND METHODS

66 MOGAD and 66 non-MOGAD children were assigned to the training set (36/35), internal test set (14/16), and external test set (16/15), respectively. At the lesion level, five single-sequence models were developed alongside a fusion model (combining these five sequences). The radiomics features of each lesion were quantified as the lesion-level radscore (LRS) using the best-performing model. Subsequently, a lesion-typing function was employed to classify lesions into two types (MOGAD-like or non-MOGAD-like), and the average LRS of the predominant type lesions in each subject was considered as the subject-level radscore (SRS). Based on SRS, a subject-level model was established and compared to both clinical models and radiologists' assessments.

RESULTS

At the lesion level, the fusion model outperformed the five single-sequence models in distinguishing MOGAD and non-MOGAD lesions (0.867 and 0.810 of area under the curve [AUC] in internal and external testing, respectively). At the subject level, the SRS model showed superior performance (0.844 and 0.846 of AUC in internal and external testing, respectively) compared to clinical models and radiologists' assessments for distinguishing MOGAD and non-MOGAD.

CONCLUSION

MRI-based radiomics models have potential clinical value for identifying MOGAD from non-MOGAD. The fusion model and SRS model can distinguish between MOGAD and non-MOGAD at the lesion level and subject level, respectively, providing a differential diagnosis method for these two diseases.

Isolated myelin oligodendrocyte glycoprotein antibody-associated optic neuritis in adults: The importance of age of onset and prognosis-related radiological features

BACKGROUND

Myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD) exhibits phenotypic diversity and it varies by age. However, less is known about whether the manifestations of isolated MOG antibody-associated optic neuritis (iMOG-ON) vary across different age groups. We aimed to investigate the clinical and prognostic features of iMOG-ON in young and middle-aged adult patients.

METHODS

Patients with iMOG-ON were enrolled in the Department of Neurology, Beijing Tongren Hospital, Capital Medical University between January 2018 and October 2021. Medical records were reviewed to obtain clinical data and orbital MRI images of adult patients with iMOG-ON. Multivariate linear regression analysis was performed to investigate the associations between final best-corrected visual acuity (BCVA) in logMAR and clinical characteristics.

RESULTS

Based on the age of onset, 70 patients were divided into 2 groups: 38 young (< 46 years; female/male = 0.76:1) and 32 middle-aged (≥ 46 years; female/male = 5.56:1) adults. There were statistical differences in both the female-to-male ratio and frequencies of contrast enhancement of the optic nerve sheaths and surrounding orbital tissues between both groups (p = 0.001, p = 0.004, respectively). The average follow-up periods were 28.04 ± 11.22 months. The median final BCVA was 0 (0 - 0.50) logMAR and 0.5 (0.3 - 1.0) logMAR in the young and middle-aged patients, respectively (p = 0.000). The multivariate linear regression analysis indicated significant positive relationships between final BCVA and age of onset (p = 0.038, 95 % CI: 0.020 - 0.728), sex (p = 0.030, 95 % CI: -0.793 - -0.042), BCVA at nadir (p = 0.000, 95 % CI: 0.164 - 0.386), and numbers of segments of optic nerve lesions (p = 0.009, 95 % CI: 0.068 - 0.450) with a coefficient of determination (R2) of 0.359 after adjusting for prior attacks of ON, time intervals between sudden-onset vision loss and administration of intravenous methylprednisolone, and corticosteroid dosages. The worst final BCVA was observed in afflicted eyes with lesions extending across three segments of the optic nerve.

CONCLUSION

Compared to young adults with iMOG-ON, the middle-aged patients tended to have a female predominance, higher frequencies of perineural enhancement, and worse visual outcomes. In addition to age of onset, visual recovery may also be influenced by patient's sex, BCVA at nadir, and lengths of longitudinally expansive lesions of the optic nerve to a certain extent.

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.

Improving the sensitivity of myelin oligodendrocyte glycoprotein-antibody testing: exclusive or predominant MOG-IgG3 seropositivity-a potential diagnostic pitfall in patients with MOG-EM/MOGAD

BACKGROUND

Myelin oligodendrocyte glycoprotein antibody-associated encephalomyelitis (MOG-EM; also termed MOG antibody-associated disease, MOGAD) is the most important differential diagnosis of both multiple sclerosis and neuromyelitis optica spectrum disorders. A recent proposal for new diagnostic criteria for MOG-EM/MOGAD explicitly recommends the use of immunoglobulin G subclass 1 (IgG1)- or IgG crystallizable fragment (Fc) region-specific assays and allows the use of heavy-and-light-chain-(H+L) specific assays for detecting MOG-IgG. By contrast, the utility of MOG-IgG3-specific testing has not been systematically evaluated.

OBJECTIVE

To assess whether the use of MOG-IgG3-specific testing can improve the sensitivity of MOG-IgG testing.

METHODS

Re-testing of 22 patients with a definite diagnosis of MOG-EM/MOGAD and clearly positive MOG-IgG status initially but negative or equivocal results in H+L- or Fc-specific routine assays later in the disease course (i.e. patients with spontaneous or treatment-driven seroreversion).

RESULTS

In accordance with previous studies that had used MOG-IgG1-specific assays, IgG subclass-specific testing yielded a higher sensitivity than testing by non-subclass-specific assays. Using subclass-specific secondary antibodies, 26/27 supposedly seroreverted samples were still clearly positive for MOG-IgG, with MOG-IgG1 being the most frequently detected subclass (25/27 [93%] samples). However, also MOG-IgG3 was detected in 14/27 (52%) samples (from 12/22 [55%] patients). Most strikingly, MOG-IgG3 was the predominant subclass in 8/27 (30%) samples (from 7/22 [32%] patients), with no unequivocal MOG-IgG1 signal in 2 and only a very weak concomitant MOG-IgG1 signal in the other six samples. By contrast, no significant MOG-IgG3 reactivity was seen in 60 control samples (from 42 healthy individuals and 18 patients with MS). Of note, MOG-IgG3 was also detected in the only patient in our cohort previously diagnosed with MOG-IgA+/IgG- MOG-EM/MOGAD, a recently described new disease subvariant. MOG-IgA and MOG-IgM were negative in all other patients tested.

CONCLUSIONS

In some patients with MOG-EM/MOGAD, MOG-IgG is either exclusively or predominantly MOG-IgG3. Thus, the use of IgG1-specific assays might only partly overcome the current limitations of MOG-IgG testing and-just like H+L- and Fcγ-specific testing-might overlook some genuinely seropositive patients. This would have potentially significant consequences for the management of patients with MOG-EM/MOGAD. Given that IgG3 chiefly detects proteins and is a strong activator of complement and other effector mechanisms, MOG-IgG3 may be involved in the immunopathogenesis of MOG-EM/MOGAD. Studies on the frequency and dynamics as well as the clinical and therapeutic significance of MOG-IgG3 seropositivity are warranted.

Body fluid markers for multiple sclerosis and differential diagnosis from atypical demyelinating disorders

INTRODUCTION

Body fluid markers could be helpful to predict the conversion into clinically definite multiple sclerosis (MS) in people with a first demyelinating event of the central nervous system (CNS). Consequently, biomarkers such as oligoclonal bands, which are integrated in the current MS diagnostic criteria, could assist early MS diagnosis.

AREAS COVERED

This review examines existing knowledge on a broad spectrum of body fluid markers in people with a first CNS demyelinating event, explores their potential to predict conversion to MS, to assess MS disease activity, as well as their utility to differentiate MS from atypical demyelinating disorders such as neuromyelitis optica spectrum disorder and myelin oligodendrocyte glycoprotein associated disease.

EXPERT OPINION

This field of research has shown a dramatic increase of evidence, especially in the last decade. Some biomarkers are already established in clinical routine (e.g. oligoclonal bands) while others are currently implemented (e.g. kappa free light chains) or considered as breakthroughs (e.g. neurofilament light). Determination of biomarkers poses challenges for continuous monitoring, especially if exclusively detectable in cerebrospinal fluid. A handful of biomarkers are measurable in blood which holds a significant potential.

Time to Disability Milestones and Annualized Relapse Rates in NMOSD and MOGAD

OBJECTIVE

To investigate accumulation of disability in neuromyelitis optica spectrum disorder (NMOSD) and myelin oligodendrocyte glycoprotein-antibody-associated disease (MOGAD) in a changing treatment landscape. We aimed to identify risk factors for the development of disability milestones in relation to disease duration, number of attacks, and age.

METHODS

We analyzed data from individuals with NMOSD and MOGAD from the German Neuromyelitis Optica Study Group registry. Applying survival analyses, we estimated risk factors and computed time to disability milestones as defined by the Expanded Disability Status Score (EDSS).

RESULTS

We included 483 patients: 298 AQP4-IgG+ NMOSD, 52 AQP4-IgG-/MOG-IgG- NMOSD patients, and 133 patients with MOGAD. Despite comparable annualized attack rates, disability milestones occurred earlier and after less attacks in NMOSD patients than MOGAD patients (median time to EDSS 3: AQP4-IgG+ NMOSD 7.7 (95% CI 6.6-9.6) years, AQP4-IgG-/MOG-IgG- NMOSD 8.7) years, MOGAD 14.1 (95% CI 10.4-27.6) years; EDSS 4: 11.9 (95% CI 9.7-14.7), 11.6 (95% lower CI 7.6) and 20.4 (95% lower CI 14.1) years; EDSS 6: 20.1 (95% CI 16.5-32.1), 20.7 (95% lower CI 11.6), and 37.3 (95% lower CI 29.4) years; and EDSS 7: 34.2 (95% lower CI 31.1) for AQP4-IgG+ NMOSD). Higher age at onset increased the risk for all disability milestones, while risk of disability decreased over time.

INTERPRETATION

AQP4-IgG+ NMOSD, AQP4-IgG-/MOG-IgG- NMOSD, and MOGAD patients show distinctive relapse-associated disability progression, with MOGAD having a less severe disease course. Investigator-initiated research has led to increasing awareness and improved treatment strategies appearing to ameliorate disease outcomes for NMOSD and MOGAD. ANN NEUROL 2024;95:720-732.

Melatonin Enhanced Microglia M2 Polarization in Rat Model of Neuro-inflammation Via Regulating ER Stress/PPARδ/SIRT1 Signaling Axis

Neuro-inflammation involves distinct alterations of microglial phenotypes, containing nocuous pro-inflammatory M1-phenotype and neuroprotective anti-inflammatory M-phenotype. Currently, there is no effective treatment for modulating such alterations. M1/M2 marker of primary microglia influenced by Melatonin were detected via qPCR. Functional activities were explored by western blotting, luciferase activity, EMSA, and ChIP assay. Structure interaction was assessed by molecular docking and LIGPLOT analysis. ER-stress detection was examined by ultrastructure TEM, calapin activity, and ERSE assay. The functional neurobehavioral evaluations were used for investigation of Melatonin on the neuroinflammation in vivo. Melatonin had targeted on Peroxisome Proliferator Activated Receptor Delta (PPARδ) activity, boosted LPS-stimulated alterations in polarization from the M1 to the M2 phenotype, and thereby inhibited NFκB-IKKβ activation in primary microglia. The PPARδ agonist L-165,041 or over-expression of PPARδ plasmid (ov-PPARδ) showed similar results. Molecular docking screening, dynamic simulation approaches, and biological studies of Melatonin showed that the activated site was located at PPARδ (phospho-Thr256-PPARδ). Activated microglia had lowered PPARδ activity as well as the downstream SIRT1 formation via enhancing ER-stress. Melatonin, PPARδ agonist and ov-PPARδ all effectively reversed the above-mentioned effects. Melatonin blocked ER-stress by regulating calapin activity and expression in LPS-activated microglia. Additionally, Melatonin or L-165,041 ameliorated the neurobehavioral deficits in LPS-aggravated neuroinflammatory mice through blocking microglia activities, and also promoted phenotype changes to M2-predominant microglia. Melatonin suppressed neuro-inflammation in vitro and in vivo by tuning microglial activation through the ER-stress-dependent PPARδ/SIRT1 signaling cascade. This treatment strategy is an encouraging pharmacological approach for the remedy of neuro-inflammation associated disorders.

Is there an immunological cross-reactivity of antibodies to the myelin oligodendrocyte glycoprotein and coronaviruses?

Recent reports indicated that myelin oligodendrocyte glycoprotein antibody-associated disease might be a rare complication after severe acute respiratory syndrome coronavirus 2 infection or vaccination. It is unclear whether this is an unspecific sequel of infection or vaccination or caused by possible immunological cross-reactivity of severe acute respiratory syndrome coronavirus 2 proteins and myelin oligodendrocyte glycoprotein. The aim of this study was therefore to elucidate whether there is an immunological cross-reactivity between severe acute respiratory syndrome coronavirus 2 spike or nucleocapsid proteins and myelin oligodendrocyte glycoprotein and to explore the relation of antibody responses against myelin oligodendrocyte glycoprotein and severe acute respiratory syndrome coronavirus 2 and other coronaviruses. We analysed serum samples from patients with severe acute respiratory syndrome coronavirus 2 infection and neurological symptoms with (myelin oligodendrocyte glycoprotein antibody-associated disease, n = 12) or without myelin oligodendrocyte glycoprotein-antibodies (n = 10); severe acute respiratory syndrome coronavirus 2 infection without neurological symptoms (n = 32); vaccinated patients with no history of severe acute respiratory syndrome coronavirus 2 infection and neurological symptoms with (myelin oligodendrocyte glycoprotein antibody-associated disease, n = 10) or without myelin oligodendrocyte glycoprotein-antibodies (n = 9); and severe acute respiratory syndrome coronavirus 2 negative/naïve unvaccinated patients with neurological symptoms with (myelin oligodendrocyte glycoprotein antibody-associated disease, n = 47) or without myelin oligodendrocyte glycoprotein-antibodies (n = 20). All samples were analysed for serum antibody responses to myelin oligodendrocyte glycoprotein, severe acute respiratory syndrome coronavirus 2, and other common coronaviruses (CoV-229E, CoV-HKU1, CoV-NL63 and CoV-OC43). Based on sample amount and antibody titres, 21 samples were selected for analysis of antibody cross-reactivity between myelin oligodendrocyte glycoprotein and severe acute respiratory syndrome coronavirus 2 spike and nucleocapsid proteins using affinity purification and pre-absorption. Whereas we found no association of immunoglobulin G and A myelin oligodendrocyte glycoprotein antibodies with coronavirus antibodies, infections with severe acute respiratory syndrome coronavirus 2 correlated with an increased immunoglobulin M myelin oligodendrocyte glycoprotein antibody response. Purified antibodies showed no cross-reactivity between severe acute respiratory syndrome coronavirus 2 spike protein and myelin oligodendrocyte glycoprotein. However, one sample of a patient with myelin oligodendrocyte glycoprotein antibody-associated disease following severe acute respiratory syndrome coronavirus 2 infection showed a clear immunoglobulin G antibody cross-reactivity to severe acute respiratory syndrome coronavirus 2 nucleocapsid protein and myelin oligodendrocyte glycoprotein. This patient was also seropositive for other coronaviruses and showed immunological cross-reactivity of severe acute respiratory syndrome coronavirus 2 and CoV-229E nucleocapsid proteins. Overall, our results indicate that an immunoglobulin G antibody cross-reactivity between myelin oligodendrocyte glycoprotein and severe acute respiratory syndrome coronavirus 2 proteins is rare. The presence of increased myelin oligodendrocyte glycoprotein-immunoglobulin M antibodies after severe acute respiratory syndrome coronavirus 2 infection may either be a consequence of a previous infection with other coronaviruses or arise as an unspecific sequel after viral infection. Furthermore, our data indicate that myelin oligodendrocyte glycoprotein-immunoglobulin A and particularly myelin oligodendrocyte glycoprotein-immunoglobulin M antibodies are a rather unspecific sequel of viral infections. Finally, our findings do not support a causative role of coronavirus infections for the presence of myelin oligodendrocyte glycoprotein-immunoglobulin G antibodies.

Predictors of relapsing disease course following index event in myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD)

BACKGROUND

Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is an autoimmune disease that can present as a monophasic or relapsing disease course. Here, we investigate the predictors of developing relapsing disease with a focus on the index event.

METHODS

MOGAD patients followed at Massachusetts General Hospital and Brigham and Women's Hospital were included. Data on demographic, clinical, and laboratory features were collected. Time-to-event survival analysis was performed using a Cox proportional hazards model. Univariate and multivariate regression analyses were performed.

RESULTS

We included 124 patients with a diagnosis of MOGAD of which 62.1% (n = 77) were female. The median (IQR) onset age and follow-up time were 31 (16, 45), and 4.08 (2.2, 7.9) years respectively. In total, 40.3% (n = 50) of patients remained monophasic and, 59.7% (n = 74) developed a relapsing course. The median (IQR) time between the index event and the second attack was 3(2, 13.7) months. Starting maintenance therapy following the index event was associated with decreased risk of relapsing disease (HR:0.26; 95%CI: 0.12, 0.54; P < 0.001). Maintenance therapy with intravenous immunoglobulin (HR:0.1; 95% CI:0.01, 0.78, P = 0.02), rituximab (HR: 0.21; 95%CI: 0.08, 0.55; P = 0.001), and mycophenolate mofetil (HR: 0.27; 95%CI: 0.09, 0.77; P = 0.01) was associated with a decreased risk of relapsing disease course. A polyphasic first attack (HR:2.4; 95%CI:1.31, 4.4; P = 0.004) and high CSF protein (HR:2.06; 95%CI: 1.01, 4.16; P = 0.04) were associated with a relapsing course.

CONCLUSIONS

In MOGAD patients, starting maintenance therapy following the index event reduces the risk of relapsing disease regardless of age, sex, and onset phenotype, while polyphasic first attack, and elevated CSF protein predict relapsing disease course.

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.

A Comparative Review of Typical and Atypical Optic Neuritis: Advancements in Treatments, Diagnostics, and Prognosis

Optic neuritis (ON) is a debilitating condition that through various mechanisms, including inflammation or demyelination of the optic nerve, can result in partial or total permanent vision loss if left untreated. Accurate diagnosis and promptly initiated treatment are imperative related to the potential of permanent loss of vision if left untreated, which can lead to a significant reduction in the quality of life in affected patients. ON is subtyped as "typical" or "atypical" based on underlying causative etiology. The etiology of ON can be differentiated when appropriate diagnostic testing is performed. Using history taking, neuroimaging, and visual testing to localize the underlying pathology of ON in a time-sensitive manner is critical in mitigating these unsatisfactory outcomes. Herein, we examine the differences in presentation, pathophysiology, and treatments of typical ON causes, like multiple sclerosis (MS), and atypical causes such as neuromyelitis optica spectrum disorder (NMOSD) and myelin oligodendrocyte glycoprotein (MOG)-immunoglobulin G (IgG) ON. The present investigation places focus on both neuroimaging and visual imaging in the differentiation of ON. Additionally, this review presents physicians with a better understanding of different presentations, treatments, and prognoses of ON.

Prodromes in demyelinating disorders, amyotrophic lateral sclerosis, Parkinson disease, and Alzheimer's dementia

A prodrome is an early set of symptoms, which indicates the onset of a disease; these symptoms are often non-specific. Prodromal phases are now recognized in multiple central nervous system diseases. The depth of understanding of the prodromal phase varies across diseases, being more nascent for multiple sclerosis for example, than for Parkinson disease or Alzheimer's disease. Key challenges when identifying the prodromal phase of a disease include the lack of specificity of prodromal symptoms, and consequent need for accessible and informative biomarkers. Further, heterogeneity of the prodromal phase may be influenced by age, sex, genetics and other poorly understood factors. Nonetheless, recognition that an individual is in the prodromal phase of disease offers the opportunity for earlier diagnosis and with it the opportunity for earlier intervention.

Effectiveness of immunotherapies in relapsing myelin oligodendrocyte glycoprotein antibody-associated disease

BACKGROUND

Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) can cause optic neuritis, transverse myelitis, or acute disseminated encephalomyelitis (ADEM). Immunotherapy is often used for relapsing disease, but there is variability in treatment decisions.

OBJECTIVE

The objective was to determine the annualized relapse rates (ARRs) and incidence rate ratios (IRRs) compared to pre-treatment and relapse-freedom probabilities among patients receiving steroids, B-cell depletion (BCD), intravenous immunoglobulin (IVIG), and mycophenolate mofetil (MMF).

METHODS

Retrospective cohort study of patients with relapsing MOGAD treated at Mass General Brigham. ARRs and IRRs compared to pre-treatment, and relapse-freedom probability and odds ratio for relapse-freedom compared to prednisone were calculated.

RESULTS

A total of 88 patients met the inclusion criteria. The ARR on IVIG was 0.13 (95% confidence interval (CI) = 0.06-0.27) and the relapse-freedom probability after at least 6 months of therapy was 72%. The ARR on BCD was 0.51 (95% CI = 0.34-0.77), and the relapse-freedom probability was 33%. The ARR on MMF was 0.32 (95% CI = 0.19-0.53) and the relapse-freedom probability was 49%. In pediatric-onset disease, MMF had the lowest ARRs (0.15, 95% CI = 0.07-0.33).

CONCLUSION

IVIG had the lowest ARRs and IRRs compared to pre-treatment and the highest relapse-freedom odds ratio compared to prednisone, while BCD had the lowest. In pediatric-onset MOGAD, MMF had the lowest ARRs.

A Noncanonical CD56dimCD16dim/- NK Cell Subset Indicative of Prior Cytotoxic Activity Is Elevated in Patients with Autoantibody-Mediated Neurologic Diseases

Neuromyelitis optica spectrum disorder (NMOSD), myelin oligodendrocyte glycoprotein Ab disease, and autoimmune myasthenia gravis (MG) are autoantibody-mediated neurologic conditions where autoantibodies can induce Ab-dependent cellular cytotoxicity (ADCC), a NK cell-mediated effector function. However, whether ADCC is a pathogenic mechanism in patients with these conditions has not been confirmed. We sought to characterize circulatory NK cells using functional assays, phenotyping, and transcriptomics to elucidate their role in pathology. NK cells from NMOSD patients and MG patients with elevated disease burden exhibited reduced ADCC and CD56dimCD16hi NK cells, along with an elevated frequency of CD56dimCD16dim/- NK cells. We determined that ADCC induces a similar phenotypic shift in vitro. Bulk RNA sequencing distinguished the CD56dimCD16dim/- population from the canonical CD56dimCD16hi cytotoxic and CD56hiCD16- immunomodulatory subsets, as well as CD56hiCD16+ NK cells. Multiparameter immunophenotyping of NK cell markers, functional proteins, and receptors similarly showed that the CD56dimCD16dim/- subset exhibits a unique profile while still maintaining expression of characteristic NK markers CD56, CD94, and NKp44. Notably, expression of perforin and granzyme is reduced in comparison with CD56dimCD16hi NK cells. Moreover, they exhibit elevated trogocytosis capability, HLA-DR expression, and many chemokine receptors, including CCR7. In contrast with NMOSD and MG, myelin oligodendrocyte glycoprotein Ab disease NK cells did not exhibit functional, phenotypic, or transcriptomic perturbations. In summary, CD56dimCD16dim/- NK cells are a distinct peripheral blood immune cell population in humans elevated upon prior cytotoxic activity by the CD56dimCD16hi NK cell subset. The elevation of this subset in NMOSD and MG patients suggests prior ADCC activity.

Mapping the global research landscape and trends of autoimmune encephalitis: A bibliometric analysis

Background

Autoimmune encephalitis (AE) is a neuroautoimmune disease featured by the presence of antibodies targeting neuronal surface, synaptic, or intracellular antigens. An increasing number of articles on its clinical manifestations, treatments, and prognosis have appeared in recent years. The objectives of this study were to summarize this growing body of literature and provide an overview of hotspots and trends in AE research using bibliometric analysis.

Methods

We retrieved AE-related articles published between 1999 and 2022 from the Web of Science Core Collection. Using bibliometric websites and software, we analyzed the data of AE research, including details about countries, institutions, authors, references, journals, and keywords.

Results

We analyzed 3348 articles, with an average of 32.83 citations per article and an H-index of 141. The USA (1091, 32.587%), China (531, 15.860%), Germany (447, 13.351%), England (266, 7.945%), and Japan (213, 6.362%) had the greatest numbers of publications. The top five institutions by numbers of publications were Oxford (143, 4.271%), the Udice French Research Universities (135, 4.032%), the University of Pennsylvania (135, 4.032%), l'Institut National de la Sante de la Recherche Medicale Inserm (113, 3.375%), and the University of Barcelona (110, 3.286%). The most productive authors were J. Dalmau (98, 2.927%), A. Vincent (65, 2.479%), H. Pruess (64, 1.912%), C. G. Bien (43, 1.284%), and F. Graus (43, 1.284%). "autoimmune encephalitis" was the most frequently used keyword (430), followed by "antibodies" (420), "NMDA receptor encephalitis" (383), and "limbic encephalitis" (368). In recent years, research hotspots have focused on the diagnosis and immunotherapy of NMDAR encephalitis and on limbic encephalitis.

Conclusion

Developed Western countries have made significant contributions to this field. China has shown a steady increase in the number of publications in recent years, but the quality and influence of these articles warrant efforts at improvement. Future directions in AE research lie in two key areas: (i) the clinical manifestations, prevalence, and prognosis of AE (enabled by advances in diagnosis); and (ii) the efficacy and safety of targeted, individualized immunotherapy.

Spectrum of various CNS inflammatory demyelination diseases following COVID-19 vaccinations

BACKGROUND AND PURPOSE

Although rare, neurological adverse events have been reported post-COVID-19 vaccination. This study reports 16 patients diagnosed with CNS inflammatory demyelinating diseases (CNS-IDD) within 6 weeks of COVID-19 vaccine administration.

METHODOLOGY

A prospective observational study was conducted from June 2021 to May 2022. All patients were diagnosed according to the latest international guidelines with CNS-IDD within 6 weeks of COVID-19 vaccine exposure. Data regarding the demographic profile, clinical features, type of COVID-19 vaccination, radiological findings and occurrence of symptoms were noted and further analysed using descriptive statistics.

RESULTS

We reported 16 cases (median age 40 years) of CNS demyelination: fourteen occurred in temporal association with ChAdOx1-S vaccine and two in association with BBV152 vaccine. Median time duration of presenting symptoms after vaccination was 19 days (3-40 days). The most common presentation was myelitis (7/16 patients), followed by optic neuritis (6/16 patients). Demyelination events were reported after first and second dose in thirteen and five patients respectively, although two patients reported such events after both vaccine dosages. Myelin oligodendrocyte glycoprotein (MOG) IgG antibodies were positive in eight patients. Tumefactive demyelination was seen in four patients. Management included high-dose methylprednisolone, PLEX, IVIG or a combination of those, with a favourable outcome in the majority of cases.

CONCLUSION

Although a rare event, awareness regarding potential demyelinating episodes post-COVID-19 vaccination can help in early diagnosis. The presence of increased MOG-IgG antibodies with temporal association in post-COVID vaccine patients raises a possibility of an immunogenic phenomenon leading to demyelinating disorders.

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.

Neurologic manifestations of autoimmunity with immune checkpoint inhibitors

Immune checkpoint inhibitors (ICIs) are cancer immunotherapies that enhance the body's own immune system to treat cancer. ICI treatment, however, can cause immune-related adverse events (irAEs) that can affect any organ, resulting in significant morbidity and mortality. Neurologic irAEs (nirAEs) are rare and can affect the peripheral nervous system more commonly than the central nervous system. Treatment is dependent on the severity of the neurologic manifestations and often includs discontinuation of the ICI and initiation of steroid therapy as the first line; other treatments have also been used. NirAEs and cardiac irAEs have higher fatality rates underlying the importance of early recognition and appropriate management. This chapter reviews the clinical manifestations of neurologic immune-related adverse events associated with ICI treatment as well as diagnostic and therapeutic modalities.

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.

Utility of the 2023 international MOGAD panel proposed criteria in clinical practice: An institutional cohort

BACKGROUND

Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is a recently defined demyelinating disorder with a rapidly evolving clinical spectrum. Recently, consensus criteria have been proposed (Banwell et al., 2023) to help with disease diagnosis. However, validation of the proposed criteria in real-life MOGAD patients is lacking. In this study, we applied the proposed criteria to an institutional cohort of MOG antibody-positive patients.

METHODS

A retrospective study was conducted at a tertiary neuroimmunology clinic from 2018 to 2023. Patients who had at least one core clinical feature of MOGAD and positive serum MOG antibody by cell-based assay were included. Demographics and clinical data were recorded and analyzed. Cases were divided into definite MOGAD, questionable MOGAD, and false-positive MOG antibody as determined by the treating neuroimmunology and/or neuro-ophthalmology specialists prior to applying the new MOGAD criteria by an independent investigator. We then calculated the sensitivity, specificity, positive predictive value, and negative predictive value of the new criteria compared to the treating physicians' assessment.

RESULTS

A total of 27 patients were included of which, 19 (70.4%) were female, the average age of the sample was 44 +/- 15 years. High titer MOG antibody (≥ 1:100) was found in 11 patients (40.7%); low titer (< 1: 100) in 13 (48.1%), and unreported titer in 3 patients. As determined by expert opinion; 18 (66.7%) were identified as definitive MOGAD, 6 (22.2%) as false-positive MOG antibody, and 3 (11.1%) as questionable MOGAD. All 18 patients identified by clinicians as definite MOGAD met the new 2023 criteria. Of the 9 patients with questionable MOGAD or false-positive MOG antibody, four patients met the 2023 MOGAD criteria. Those four patients had the following final diagnoses: CNS vasculitis, primary progressive MS with activity and progression, pseudotumor cerebri, and bevacizumab-induced anterior ischemic optic neuropathy in the setting of paraneoplastic retinopathy. Compared to clinician assessment, applying the 2023 MOGAD criteria to our institutional cohort yielded a sensitivity of 100%, a specificity of 55.5%, a positive predictive value of 81.5% and a negative predictive value of 100%.

CONCLUSION

These findings suggest that the 2023 MOGAD criteria are highly sensitive for detection of definite MOGAD but has modest specificity. A number of MOGAD mimickers can resemble the core clinical events of MOGAD and share similar supportive clinical and MRI features. Clinicians should practice caution when evaluating patients with low titer MOG antibody even if they meet the additional supportive features proposed by the 2023 criteria. Further studies are needed to evaluate the 2023 criteria in larger cohorts and in the pediatric population.

Mitoxantrone in NMO Spectrum Disorder in a Large Multicenter Cohort in French Caribbean

BACKGROUND AND OBJECTIVES

Preventing relapses in neuromyelitis Optica spectrum disorder (NMOSD) is a primary goal. New effective molecules are often expensive and not readily available in regions with fragile health systems. Assessing the efficacy and safety of less costly therapeutic alternatives is necessary. We aim to evaluate the efficacy and safety of mitoxantrone (MiTX) in NMOSD.

METHODS

This is an observational, multicenter, open study of 86 NMOSD-treated patients with prospective follow-up over 30 years. The first endpoint was the first relapse at the 96-week follow-up. The secondary endpoints were to evaluate the median delay to relapse, the annualized relapse rate (ARR), and the Expanded Disability Status Scale (EDSS) at 96 weeks of follow-up and to assess risk factors of relapse and the occurrence of severe adverse effects.

RESULTS

At 96-week follow-up, 71% of our patients were relapse-free, and it was 87% when patients were treated with MiTX from the first attack. The ARR dropped from 0.85 (±0.55) to 0.32 (±0.63) (p < 0.001) and EDSS from 4.9 (±2.4) to 4.2 (±2.6) (p < 0.001). AQP4-IgG seropositivity (hazard ratio [HR] 12.3, 95% CI 1.64-91.6, p = 0.015), a delay between the first attack and MiTX ≥24 months (HR 2.76, 95% CI 1.23-6.17, p = 0.014), and a pretreatment ARR ≥1 (HR 2.38, 95% CI 1.05-5.39, p = 0.037) were predictors of relapse. During the entire follow-up, severe secondary adverse events occurred in 3 patients (3.5%).

DISCUSSION

MiTX is an effective and safe treatment for most of our patients, drastically less expensive than new molecules, and could be allowed in NMOSD Afro-descendant patients in geographical areas where access to care is difficult.

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.

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.

Diagnostic Value of Multiparameter MRI-Based Radiomics in Pediatric Myelin Oligodendrocyte Glycoprotein Antibody-Associated Disorders

BACKGROUND AND PURPOSE

Myelin oligodendrocyte glycoprotein antibody-associated disorders (MOGAD) have a higher prevalence among children. For children undergoing the initial manifestation of MOGAD, prompt diagnosis has paramount importance. This study assessed the performance of multiparameter MRI-based radiomics in distinguishing patients with and without MOGAD with idiopathic inflammatory demyelinating diseases.

MATERIALS AND METHODS

We enrolled a cohort of 121 patients diagnosed with idiopathic inflammatory demyelinating diseases, including 68 children with MOGAD and 53 children without MOGAD. Radiomics models (T1WI, T2WI, FLAIR, and compound model) using features extracted from demyelinating lesions within the brain parenchyma were developed in the training set. The performance of these models underwent validation within the internal testing set. Additionally, we gathered clinical factors and MRI features of brain parenchymal lesions at their initial presentation. Subsequently, these variables were used in the construction of a clinical prediction model through multivariate logistic regression analysis.

RESULTS

The areas under the curve for the radiomics models (T1WI, T2WI, FLAIR, and the compound model) in the training set were 0.781 (95% CI, 0.689-0.864), 0.959 (95% CI, 0.924-0.987), 0.939 (95% CI, 0.898-0.979), and 0.989 (95% CI, 0.976-0.999), respectively. The areas under the curve for the radiomics models (T1WI, T2WI, FLAIR, and the compound model) in the testing set were 0.500 (95% CI, 0.304-0.652), 0.833 (95% CI, 0.697-0.944), 0.804 (95% CI, 0.664-0.918), and 0.905 (95% CI, 0.803-0.979), respectively. The areas under the curve of the clinical prediction model in the training set and testing set were 0.700 and 0.289, respectively.

CONCLUSIONS

Multiparameter MRI-based radiomics helps distinguish MOGAD from non-MOGAD in patients with idiopathic inflammatory demyelinating diseases.

Case report: GCA like picture-preceding inaugural MOGAD presentation: A patient with a sudden-onset uniocular blindness

RATIONALE

Myelin oligodendrocyte glycoprotein antibody-associated disorders (MOGAD) represents a demyelinating neurological syndrome characterized by the presence of serum IgG antibodies directed against myelin oligodendrocyte glycoprotein (MOG-IgG). Concurrently, giant cell arteritis (GCA) constitutes a systemic autoimmune vasculitis.

PATIENT CONCERNS

In this case, we describe an elderly female patient who presented with the sudden onset of a severe headache, unilateral blindness, and clinical manifestations resembling those of GCA.

DIAGNOSIS

Upon conducting a comprehensive analysis of serum antibodies, the diagnosis of MOGAD was established due to the presence of detectable serum MOG-IgG.

INTERVENTIONS

Subsequently, the patient was administered intravenous methylprednisolone therapy, commencing 27 days after the initial onset of symptoms.

OUTCOMES

It is noteworthy that patients afflicted by MOGAD typically manifest severe visual impairment, which, in many instances, exhibits significant improvement following immunotherapeutic interventions. However, this particular patient did not experience any amelioration in visual function despite glucocorticoid therapy.

LESSONS

This unique case illustrates that the clinical presentation resembling GCA may precede the inaugural manifestation of MOGAD. This suggests the possibility of immune-mediated arterial involvement. The significance of glucocorticoid therapy in the context of immune-related diseases warrants further scrutiny, particularly in cases where MOG-IgG screening should be promptly considered.

Delimiting MOGAD as a disease entity using translational imaging

The first formal consensus diagnostic criteria for myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) were recently proposed. Yet, the distinction of MOGAD-defining characteristics from characteristics of its important differential diagnoses such as multiple sclerosis (MS) and aquaporin-4 antibody seropositive neuromyelitis optica spectrum disorder (NMOSD) is still obstructed. In preclinical research, MOG antibody-based animal models were used for decades to derive knowledge about MS. In clinical research, people with MOGAD have been combined into cohorts with other diagnoses. Thus, it remains unclear to which extent the generated knowledge is specifically applicable to MOGAD. Translational research can contribute to identifying MOGAD characteristic features by establishing imaging methods and outcome parameters on proven pathophysiological grounds. This article reviews suitable animal models for translational MOGAD research and the current state and prospect of translational imaging in MOGAD.

Systematic review exploring the clinical features of optic neuritis after SARS-CoV infection and vaccination

BACKGROUND

This study aims to characterise the symptoms and clinical features of optic neuritis (ON) following SARS-CoV-2 infection and vaccination.

METHOD

A literature search was conducted in four databases (PubMed, Medline, Embase and Google Scholar) to identify relevant case reports and case series. The records were screened and articles adhering to the inclusion criteria were critically appraised.

RESULTS

Sixty-eight studies were found to be eligible for inclusion, including 34 reporting ON following SARS-CoV-2 infection and an equal number reporting cases postvaccination. In total 93 patients and 125 eyes were included. The infection cohort included 42 patients and 56 eyes, 51.2% were female and 33.3% experienced bilateral ON. The mean visual acuity was 1.64 log of minimum angle of resolution (LogMAR), while pain was present in 77.8%. Oligoclonal bands were present in 3 patients, myelin oligodendrocyte glycoprotein (MOG) antibodies in 18 patients and AQP-4 antibodies in 4 patients. The vaccination cohort included 51 patients and 69 eyes. 60.8% were female and 35.3% had a bilateral ON. The mean visual acuity was 0.93 LogMAR. Oligoclonal bands were present in 46.7%, MOG antibodies in nine patients and AQP-4 antibodies in three patients.

CONCLUSION

Patients with ON post-SARS-CoV infection were more likely to experience severe visual impairment than in cases following vaccination. Further research is required to outline the clinical features of ON after COVID-19 infection and vaccination, and establish causality.

Clinical Features and Prognostic Factors in Anti-Myelin Oligodendrocyte Glycoprotein Antibody Positive Optic Neuritis

In order to review the clinical features of anti-myelin oligodendrocyte glycoprotein antibody positive optic neuritis (MOGON), we investigated the clinical characteristics, visual function, optical coherence tomography findings, and magnetic resonance imaging of 31 patients (44 eyes). MOGON was more common in middle age without sex difference and was characterised by pain on eye movement and optic disc swelling. Magnetic resonance imaging lesions tended to be long with inflammation around the optic nerve sheath; longer lesions were associated with worse visual acuities at onset. Recurrence was significantly associated with retinal nerve fibre layer thinning, and thus, it is important to reduce recurrence as much as possible.

Cervical myelitis: a practical approach to its differential diagnosis on MR imaging

BACKGROUND

 Differential diagnosis of non-compressive cervical myelopathy encompasses a broad spectrum of inflammatory, infectious, vascular, neoplastic, neurodegenerative, and metabolic etiologies. Although the speed of symptom onset and clinical course seem to be specific for certain neurological diseases, lesion pattern on MR imaging is a key player to confirm diagnostic considerations.

METHODS

 The differentiation between acute complete transverse myelitis and acute partial transverse myelitis makes it possible to distinguish between certain entities, with the latter often being the onset of multiple sclerosis. Typical medullary MRI lesion patterns include a) longitudinal extensive transverse myelitis, b) short-range ovoid and peripheral lesions, c) polio-like appearance with involvement of the anterior horns, and d) granulomatous nodular enhancement prototypes.

RESULTS AND CONCLUSION

 Cerebrospinal fluid analysis, blood culture tests, and autoimmune antibody testing are crucial for the correct interpretation of imaging findings. The combination of neuroradiological features and neurological and laboratory findings including cerebrospinal fluid analysis improves diagnostic accuracy.

KEY POINTS

  · The differentiation of medullary lesion patterns, i. e., longitudinal extensive transverse, short ovoid and peripheral, polio-like, and granulomatous nodular, facilitates the diagnosis of myelitis.. · Discrimination of acute complete and acute partial transverse myelitis makes it possible to categorize different entities, with the latter frequently being the overture of multiple sclerosis (MS).. · Neuromyelitis optica spectrum disorders (NMOSD) may start as short transverse myelitis and should not be mistaken for MS.. · The combination of imaging features and neurological and laboratory findings including cerebrospinal fluid analysis improves diagnostic accuracy.. · Additional brain imaging is mandatory in suspected demyelinating, systemic autoimmune, infectious, paraneoplastic, and metabolic diseases..

Progression independent of relapses in aquaporin4-IgG-seropositive neuromyelitis optica spectrum disorder, myelin oligodendrocyte glycoprotein antibody-associated disease, and multiple sclerosis

OBJECTIVES

To determine whether progression independent of relapse activity (PIRA) is present in Aquaporin4-IgG-seropositive neuromyelitis optica spectrum disorder (AQP4+NMOSD), Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) and relapsing remitting Multiple sclerosis (RRMS).

METHODS

We retrospectively studied the change in EDSS, confirmed disability worsening (CDW) (i.e., PIRA), and new MRI lesions in AQP4+NMOSD, and MOGAD and MS patients. Linear mixed-effect regression model was used to compare the longitudinal changes in EDSS, and Cox regression was used to compare changes in MRI.

RESULTS

The estimated mean ΔEDSS in the AQP4+NMOSD and matched MS group were +0.06 (95%CI: -0.40, +0.52, p = 0.76), and +0.02 (95%CI: -0.05, +0.08, p = 0.6) respectively. The same estimate was -0.08 (95%CI: -0.18, +0.02, p = 0.12) in MOGAD and +0.05 (95%CI: -0.05, +0.15, p = 0.35) in matched MS group. Comparing groups for the presence of CDW (i.e., PIRA) showed that PIRA is more associated with MS compared to AQP4+NMOSD (p = 0.02) and MOGAD (p<0.001). Compared to their matched MS groups, the annualized rate of PIRA was significantly lower in AQP4 (0.08 vs 0.44; p<0.0001), and MOG groups (0.04 vs 0.13; p<0.0001). New T2 or enhancing lesions on brain MRI were higher in MS compared to AQP4+NMOSD and MOGAD patients.

CONCLUSION

Relapse-independent changes in the EDSS, CDW, and MRI activity are not common in AQP4+NMOSD and MOGAD, especially when compared with MS. Since our patients were on relapse prevention therapies at the time of EDSS measurements, our study supports the importance of preventing relapses in AQP4+NMOSD and MOGAD and suggests different pathologic mechanisms of relapse-free neurological damage between MS and AQP4+NMOSD/MOGAD.

SARS-CoV-2 Parainfectious Optic Neuropathy: 3 Case Reports and a Review of the Literature

BACKGROUND

Parainfectious optic neuritis is an inflammatory reaction that occurs shortly after an infection without direct invasion by a pathogen. The clinical profile depends on the infectious organism. Cases of SARS-CoV-2 parainfectious optic neuritis have been reported in the literature, but there are no reviews that have applied strict inclusion criteria to more definitively establish the clinical profile associated with SARS-CoV-2.

METHODS

We present 3 new cases of SARS-CoV-2 parainfectious optic neuritis. We also review the literature for definite cases by selecting only those with unambiguous clinical features and MRI findings of optic neuritis, positive SARS-CoV-2 polymerase chain reaction or serology, and the absence of myelin oligodendrocyte-glycoprotein or aquaporin-4 antibodies or other diseases associated with optic neuritis.

RESULTS

We report 2 cases of monophasic, unilateral SARS-CoV-2 parainfectious optic neuritis with optic disc edema and nadir visual acuities of finger counting. We report 1 case of mild SARS-CoV-2 parainfectious optic neuritis that featured cotton wool spots, peripapillary wrinkles and hemorrhages, and recurrence after an initial steroid taper. We identified 6 cases of unambiguous SARS-CoV-2 parainfectious optic neuritis from the literature. Combining our case series with the case reports in the literature, the average age was 42.8 years, 3/9 had bilateral disease, 6/8 had optic disc edema, 8/9 had nadir visual acuity of finger counting or worse, and all recovered visual acuity to 20/40 or better after therapy with steroids.

CONCLUSIONS

SARS-CoV-2 parainfectious optic neuritis has a clinical profile that is atypical for idiopathic optic neuritis but fairly typical of parainfectious forms of optic neuritis with a severely reduced nadir visual acuity, high likelihood of bilaterality, high incidence of optic disc edema, and prompt and significant response to corticosteroids. Further study with long-term follow-up and epidemiologic investigation will be needed to further characterize this clinical entity.

NF-κB and STAT3 activation in CD4 T cells in pediatric MOG antibody-associated disease

In this study, we examined CD4 T cell activation using various stimuli in pediatric MOGAD patients (n = 4, untreated remission samples) and healthy controls (n = 5), to understand how both antigen-specific and bystander mechanisms contribute to CD4 T cell activation in MOGAD. TNFα, IL6, and MOG peptide pool were found to activate NF-κB or STAT3 pathways by measuring the expression of regulators (A20, IκBα) and phosphorylated subunits (phospho-p65 and phospho-STAT3) using immunolabeling. Prednisolone reversed activation of both NF-κB and STAT3 and increased the expression of A20 and IκBα. TNFR blocking partially reversed NF-κB activation in certain CD4 T cell subsets, but did not effect STAT3 activation. We observed that activation of NF-κB and STAT3 in response to various stimuli behaves mostly same in MOGAD (remission) and HC. IL6 stimulation resulted in higher STAT3 phosphorylation in MOGAD patients at 75 min, specifically in central and effector memory CD4 T cells (with unadjusted p-values). These findings suggest the potential therapeutic targeting of NF-κB and STAT3 pathways in MOGAD. Further investigation is needed to validate the significance of extended STAT3 phosphorylation and its correlation with IL6 receptor blocker treatment response.

Neuromyelitis Optica spectrum disorders in Argentina: A hospital-based study

BACKGROUND

Neuromyelitis Optica spectrum disorder (NMOSD) is an antibody-mediated autoimmune disease of the CNS, which especially affects the optic nerves and spinal cord. There is little known in Latin America (LATAM) about NMOSD, and few reports have been published in the literature so far. We aimed to describe an NMOSD study in a single center from Argentina.

METHODS

A retrospective cross sectional study was carried out in a single reference center in the city of Buenos Aires, Argentina. Data were collected from January 2000 through December 2021 using medical records from patients attending Ramos Mejia Hospital in Buenos Aires, Argentina. Here we describe the clinical, laboratory, MRI, disability course, and treatment of 92 NMOSD patients.

RESULTS

Mean age at the onset of symptoms was 31 years (range 2-68) with a female/male ratio of 4.8:1. 71.7 % had an early onset before the age of 50 years old, 8.7 % had a late onset of the disease and 19.6 % had an onset at pediatric age. The first symptom of NMOSD was optic neuritis in 47.8 % of the patients, followed by transverse myelitis, 33.7 % and area postrema syndrome, 5.4 %. 96.7 % of patients relapsed at least once during the follow-up period. The mean of the expanded disability status scale (EDSS) was 4.0 (range 2-8). 34,8 % had one or more associated autoimmune diseases. 78,6 % had a positive result for AQP4-IgG. The ratio of male to female was 1:8.4 vs.1:1.2 in the seropositive group vs. the seronegative. CSF results showed OCB type 2 in 6.3 %. The brain MRI did not show brain lesions in 71,7 % of the patients. 17 % presented spinal cord lesions with less than 3 vertebral segments. All patients received treatment with immunosuppressive drugs. Rituximab and azathioprine were the most used.

CONCLUSIONS

This is the largest hospital-based study in an Argentina cross-sectional study of patients with NMOSD. Recurrent disease, early age at onset, female prevalence in AQP4-IgG+ patients, and the difficulty to assess new treatments, are the highlight features in our study of patients. Further Argentinian and LATAM studies will provide more information.

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.

Clinical characteristics and long-term follow-up outcomes of myelin oligodendrocyte glycoprotein antibody-associated disease in Han Chinese participants

Myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD) is an immune-mediated inflammatory demyelinating disease of the central nervous system. This study aimed to delineate the clinical manifestations, imaging features, and long-term outcomes in Chinese patients with MOGAD and analyze the recurrence-associated factors. The phenotypic and neuroimaging characteristics of 15 Han Chinese patients with MOGAD were retrospectively analyzed. Demyelinating attacks, MOG antibodies in the cerebrospinal fluid/serum, response to immunotherapy, follow-up outcomes, and recurrence-associated factors were recorded. The median age at disease onset was 34 years (range, 4-65 years). The most common initial presentations included vision loss (10/15, 66.7%) and seizures (5/15, 33.3%). Serum MOG-Ab titers in 14/15 cases were higher than those in the cerebrospinal fluid and were detected in 3/6 relapsed patients. Brain magnetic resonance imaging during acute attacks showed lesions in 10/15 patients (66.7%), mostly in the cortex/subcortical white matter (5/15, 33.3%). Recurrence occurred in 6/15 patients (40.0%); in 4 patients, recurrence occurred shortly after immunotherapy discontinuation. Residual neurological deficits were present in 5/15 patients (33.3%), including visual impairment, incapacitation, cognitive impairment, and speech reduction. Optic neuritis was the most common clinical manifestation of MOGAD. magnetic resonance imaging findings were heterogeneous and the cerebral cortex/subcortical white matter was the most susceptible brain region. Although patients in the acute phase responded well to methylprednisolone pulse therapy, the long-term recurrence rate was high. Consistently detected serum MOG antibodies and inappropriate maintenance immunotherapy may be associated with recurrence, and residual neurological deficits should not be ignored.

Perplexing Initial Presentations of MOGAD in Two Children: Intracranial Hypertension and New-Onset Seizure

We report two distinct challenging initial presentations of myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD). Case 1 describes a 12-year-old boy who developed headaches refractory to pain medication followed by cranial neuropathies and intracranial hypertension, confirmed by lumbar puncture with an opening pressure >36 cm H2O. Case 2 describes a 3-year-old boy who developed new-onset seizures refractory to antiseizure medications, a presentation of FLAIR-hyperintense lesions in MOG-antibody associated encephalitis with seizures (FLAMES). On repeat magnetic resonance imaging, both patients were found to have cortical T2 hyperintensities, leptomeningeal contrast enhancement, and bilateral optic nerve enhancement. In the cerebrospinal fluid, both patients had CSF pleocytosis with neutrophilic predominance. The patients were treated with intravenous immunoglobulins, plasma exchange, and high-dose corticosteroids. The first patient achieved disease remission, whereas the second patient required the addition of rituximab for management of seizures. The two cases highlight the pleomorphic clinical phenotypes of MOGAD.

An update on optic neuritis

Optic neuritis (ON) is the most common cause of subacute optic neuropathy in young adults. Although most cases of optic neuritis (ON) are classified as typical, meaning idiopathic or associated with multiple sclerosis, there is a growing understanding of atypical forms of optic neuritis such as antibody mediated aquaporin-4 (AQP4)-IgG neuromyelitis optica spectrum disorder (NMOSD) and the recently described entity, myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD). Differentiating typical ON from atypical ON is important because they have different prognoses and treatments. Findings of atypical ON, including severe vision loss with poor recovery with steroids or steroid dependence, prominent optic disc edema, bilateral vision loss, and childhood or late adult onset, should prompt serologic testing for AQP4-IgG and MOG-IgG. Although the traditional division of typical and atypical ON can be helpful, it should be noted that there can be severe presentations of otherwise typical ON and mild presentations of atypical ON that blur these traditional lines. Rare causes of autoimmune optic neuropathies, such as glial fibrillary acidic protein (GFAP) and collapsin response-mediator protein 5 (CRMP5) autoimmunity also should be considered in patients with bilateral painless optic neuropathy associated with optic disc edema, especially if there are other accompanying suggestive neurologic symptoms/signs. Typical ON usually recovers well without treatment, though recovery may be expedited by steroids. Atypical ON is usually treated with intravenous steroids, and some forms, such as NMOSD, often require plasma exchange for acute attacks and long-term immunosuppressive therapy to prevent relapses. Since treatment is tailored to the cause of the ON, elucidating the etiology of the ON is of the utmost importance.

Clinical feature and disease outcome in patients with myelin oligodendrocyte glycoprotein antibody-associated disorder: a Chinese study

BACKGROUND

To identify factors associated with relapse risk and disability in myelin oligodendrocyte glycoprotein antibody-associated disorder (MOGAD).

METHOD

Between 2016 and 2021, 186 patients with MOGAD were included in the study. Factors associated with a relapsing course, annualised relapse rate (ARR), recurrent relapses under different maintenance treatments and unfavourable disability outcome were analysed.

RESULTS

MOGAD affects women (53.8%) slightly more often than men. After a median disease duration of 51.0 months, 60.2% (112/186) relapsed, with an overall ARR of 0.5. The ARR (0.6 vs 0.4, p=0.049), median Expanded Disability Status Scale (EDSS) score (1 (range 0-9.5) vs 1 (range 0-3.5), p=0.005) and Visual Functional System Score (VFSS) (0 (range 0-6) vs 0 (range 0-3), p=0.023) at last visit were higher in adults than in children, and time to first relapse was shorter in adults than in children (4.1 (range 1.0-111.0) vs 12.2 (range 1.3-266.8) months, p=0.001). Myelin oligodendrocyte glycoprotein antibody (MOG-ab) persistence over 1 year was associated with a relapsing course (OR 7.41, 95% CI 2.46 to 22.33, p=0.000), while timely maintenance therapy was associated with a lower ARR (p=0.008). More than four attacks (OR 4.86, 95% CI 1.65 to 14.28, p=0.004) and poor recovery from the first attack (OR 75.28, 95% CI 14.45 to 392.05, p=0.000) were associated with an unfavourable outcome (EDSS score ≥2 including VFSS ≥2).

CONCLUSIONS

The results underscored the importance of timely maintenance treatment to prevent further relapses, especially in adult patients with persistently positive MOG-ab and unsatisfactory recovery from the onset attack.