Myelin-oligodendrocyte glycoprotein antibody-associated disease

Maternal-infant probiotic transmission mitigates early-life stress-induced autism in mice

Autism, a disorder influenced by both genetic and environmental factors, presents significant challenges for prevention and treatment. While maternal-infant gut microbiota has been a focus in autism research, preventive strategies targeting maternal gut microbiota remain underexplored. This study demonstrates that prenatal probiotic intake can effectively prevent maternal separation-induced autistic-like behaviors in offspring without altering the embryonic neurodevelopment in mice. Using specific PCR primers and cross-fostering experiments, we traced the vertical transmission of probiotics, primarily via fecal/vaginal contamination. Early probiotic colonization conferred resilience against stress-induced gut pathogenic microbes and Th17-mediated peripheral inflammation while significantly inhibiting hypermyelination and neuroinflammation linked to systemic inflammation. Microbial metabolites like tyrosol and xanthurenic acid alleviated neuroinflammation and hypermyelination in vitro, though the causal relationship among neuroinflammation, hypermyelination, and autism in vivo requires further validation. These findings underscore the importance of the maternal-infant microbiota transmission window in autism prevention and highlight the clinical potential of prenatal probiotic interventions.

Diagnosis and Management of Children With Atypical Neuroinflammation

Pediatric neuroimmune disorders comprise a heterogeneous group of immune-mediated CNS inflammatory conditions. Some, such as multiple sclerosis, are well defined by validated diagnostic criteria. Others, such as anti-NMDA receptor encephalitis, can be diagnosed with detection of specific autoantibodies. This review addresses neuroimmune disorders that neither feature a diagnosis-defining autoantibody nor meet criteria for a distinct clinicopathologic entity. A broad differential in these cases should include CNS infection, noninflammatory genetic disorders, toxic exposures, metabolic disturbances, and primary psychiatric disorders. Neuroimmune considerations addressed in this review include seronegative autoimmune encephalitis, seronegative demyelinating disorders such as neuromyelitis optica spectrum disorder, and genetic disorders of immune dysregulation or secondary neuroinflammation. In such cases, we recommend a broad diagnostic workup to support the presence of neuroinflammation, exclude non-neuroimmune disorders, detect autoantibodies and other biomarkers of known diseases, identify any potential genetic drivers of neuroinflammation, and provide case-specific insights into pathophysiologic mechanisms of inappropriate immune pathway activation or dysregulation. This review includes an extensive list of useful diagnostic tests and potential implications thereof, as well as a proposed algorithm for the diagnosis and management of the pediatric patient with atypical neuroimmune disorders. In general, first-line acute treatment of neuroimmune disorders begins with steroids, along with consideration of plasmapheresis or IV immunoglobulin. Selection of second-line or maintenance therapy is challenging without a definite, specific diagnosis and the associated benefit of established evidence-based treatment options. Immunotherapies may be considered based on the suspected mechanism of neuroinflammation and the likelihood of relapse. For example, rituximab may be considered for possible antibody-mediated or B-cell-mediated inflammation while anti-interleukin (IL)-6 agents, anti-IL-1 agents, or JAK inhibitors may be considered for certain cases of cytokine-mediated inflammation or innate immune system dysregulation. Care should be taken to monitor response and disease activity, revisit the differential diagnosis in the case of unexpected findings or poor treatment response, and weigh the risks of immunotherapy with the benefits of empiric treatment. Over time, further advancements in biomarker identification and omics research may define specific new clinicopathologic diagnoses and thus obviate the need for "n of 1" approaches to what are currently heterogeneous groups of atypical seronegative neuroimmune disorders.

Clinical features of recurrent MOG antibody-associated cortical encephalitis in adults

OBJECTIVE

To clarify the clinical features of recurrent myelin oligodendrocyte glycoprotein antibody-associated cortical encephalitis (MOGCE) in adults.

METHODS

We present an adult case of recurrent MOGCE and summarize the clinical symptoms, imaging findings, treatment and prognosis of this phenotype as per a systematic review of the literature.

RESULTS

We identified 9 adult patients with recurrent MOGCE. The mean age was 32 years, and 5/9 were male. Median time to recurrence was 6 months (range 2-36 months). The most common presentations of the first attack were headache (9/9), fever (8/9) and seizure (5/9). In most patients (6/9), presentations of recurrent attacks were different than those of the first attack. Relapses may affect more areas than the first attack, such as spine, brainstem, grey matter, and basal ganglia. All patients were seropositive for MOG antibodies during the first or second attack, with antibody titers ranging from 1:10 to 1:100. CSF white blood cell count and total protein were elevated in 6/9 patients. On MRI, 4/9 showed bilateral FLAIR hyperintense lesions, while 5/9 had unilateral lesions. Most patients demonstrated a positive response to treatment, and maintenance immunotherapy was added upon relapse.

CONCLUSION

The clinical presentation of recurrent MOGCE is atypical, and most patients had different symptoms upon recurrence compared to the first episode. Factors contributing to the likelihood of disease recurrence remain unclear. Most recurrent MOGCE patients respond well to immunotherapy, and require long-term immunotherapy after recurrence.

Brain and Spine Magnetic Resonance Imaging (MRI) Characteristics of a Pediatric Cohort With MOGAD

Background and ObjectivesMyelin-oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is a recently defined demyelinating disorder with an age-related phenotypic spectrum. At disease onset, there is considerable clinical overlap between MOGAD and other demyelinating conditions, and it remains difficult to identify MOGAD radiographically. This study aims to further describe neuroimaging findings in the brain and the spine at presentation and throughout relapses in children with MOGAD.MethodsWe present a retrospective cohort study including all children presenting to a single center between 2010 and 2020 with acute demyelination who were positive for serum MOG-IgG antibodies and negative for serum aquaporin-4 antibodies. For each patient, magnetic resonance imaging (MRI) scans of the brain and spine at presentation and on each relapse were reviewed and categorized in a blinded fashion by 2 pediatric neuroradiologists.ResultsSixteen patients met the inclusion criteria. Four had diffuse and bilateral fluid-attenuated inversion recovery signal in the white matter, but only on initial presentation. The area postrema was never affected. All 5 patients with optic neuritis had pre-chiasmatic (but not chiasmatic) involvement on presentation. The brachium pontis was involved in 3 patients on initial presentation, and in 8 patients at any time. Eleven patients demonstrated spinal cord involvement, and the cervical, thoracic, and lumbar regions were involved at similar frequencies.DiscussionThe radiographic features of MOGAD in children appear to reflect their presenting demyelinating syndromes. However, certain features, such as diffuse fluid-attenuated inversion recovery hyperintensities and expansile fluid-attenuated inversion recovery signal in the brachium pontis, may be more frequent in MOGAD compared with other demyelinating disorders.

Diagnostic Utility of Kappa Free Light Chain Index in Adults With Inaugural Optic Neuritis

BACKGROUND AND OBJECTIVES

A simple, quick, and reproducible procedure for distinguishing multiple sclerosis (MS), myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD), and neuromyelitis optica spectrum disorder (NMOSD) at inaugural optic neuritis (ION) could be highly valuable in guiding early management.

METHODS

We included all adults admitted to the MS center of Marseille for ION between March 2016 and April 2024, with CSF analysis including the kappa free light chain (K-FLC) index. Receiver operating characteristic curves were used to measure the diagnostic ability of the K-FLC index.

RESULTS

Two hundred twenty-seven adults were admitted for ION; 210 (93%) had a K-FLC index measurement. MS was diagnosed in 84 (40%); clinically isolated syndrome suggestive of MS in 77 (36.5%), including 20 with future conversion to MS (CISwc); MOGAD in 26 (12.5%); NMOSD in 13 (6%); and other inflammatory disorders in 10 (5%). A K-FLC index ≥6.7 differentiated MS/CISwc from other diagnoses with specificity 86% and sensitivity 95% (area under the curve [AUC] 0.94). A K-FLC index <4.9 differentiated MOGAD from other diagnoses with specificity 63% and sensitivity 92% (AUC 0.78) and MOGAD from MS/CISwc with specificity 96% and sensitivity 92% (AUC 0.97). Among all patients, 93 (44%) had a K-FLC index <4.9: 24 of these (26%) had MOGAD and 5 (5.5%) MS/CISwc. Among the remaining patients with a K-FLC index ≥4.9 (n = 117), 2 (1.7%) had MOGAD (K-FLC index of 7.9 and 16.2) and 99 (85%) MS/CISwc. Among patients with normal MRI (n = 96), 73 (76%) had a K-FLC index <4.9: 22 of these (30%) had MOGAD, and none showed conversion to MS. Among the remaining patients with a K-FLC index ≥4.9 (n = 23), 2 (8.5%) had MOGAD and 7 (30.5%) showed conversion to MS. The K-FLC index did not differentiate NMOSD from other diagnoses and only moderately differentiated NMO from MS/CISwc (AUC 0.80).

DISCUSSION

The K-FLC index is an accessible biomarker to guide early diagnosis in patients with ION. The probability of MOGAD in patients with ION and a K-FLC index ≥4.9 is low even in case of normal brain/spinal cord MRI.

CLASSIFICATION OF EVIDENCE

This study provides Class II evidence that for patients with ION, the K-FLC index can distinguish between MS/CISwc and MOGAD.

Distinguishing Neuromyelitis Optica Spectrum Disorders Subtypes: A Study on AQP4 and C3d Epitope Expression in Cytokine-Primed Human Astrocytes

Neuromyelitis optica spectrum disorders (NMOSD) are severe autoimmune conditions affecting the central nervous system. In a subset of cases, no autoantibodies are detectable with the currently used routine assays. This study aimed to determine whether the levels of expression of aquaporin-4 (AQP4), excitatory amino acid transporter 2 (EAAT2), or complement C3/C3d and C5b-9 in human astrocytes following incubation with patient sera under inflammatory conditions differ between the various NMOSD subtypes and whether such differences can help to identify autoantibody-mediated cases of NMOSD. Levels of AQP4, EAAT2, complement C3/C3d and C5b-9 epitope expression on human astrocytes pretreated with various cytokines were quantitatively analyzed via indirect immunofluorescence after exposure to sera from patients with AQP4-IgG seropositive, MOG-IgG seropositive, and AQP4/MOG-IgG double seronegative NMOSD. Significant differences in AQP4 and C3d epitope expression were observed, with IL-17A, IL-10, and IL-6 pre-treatment notably influencing astrocytic responses. Using uniform manifold approximation and projection (UMAP), patients were classified into clusters corresponding to AQP4-IgG seropositive, MOG-IgG seropositive, or double seronegative NMOSD. These results demonstrate distinct astrocytic staining patterns across NMOSD subtypes, providing a potential diagnostic tool for distinguishing between autoantibody-mediated astrocytopathy and other cases. These findings suggest specific pathogenic mechanisms linked to each NMOSD subtype, which may have implications for tailoring therapeutic strategies based on cytokine involvement and astrocyte reactivity.

Multiple sclerosis: an immune attack on astrocyte-mediated ion and water homeostasis

Multiple sclerosis (MS) is an inflammatory demyelinating disease of the CNS. The chain of events that results in demyelinating lesions is not understood, although most theories assume a primary immune attack on myelin. However, the glial cell adhesion molecule GlialCAM, which forms part of a protein complex in astrocytic endfeet that is crucial for brain ion and water homeostasis, was recently identified as a target for autoimmunity in patients with MS. This complex also includes the astrocytic transmembrane protein MLC1, the water channel aquaporin 4 (AQP4) and the potassium channel KIR4.1. Autoimmunity against AQP4 underlies another demyelinating disorder, neuromyelitis optica, and autoimmunity against KIR4.1 has been implicated in a subtype of MS. Genetic defects in any of these proteins cause leukodystrophies with disruption of brain ion and water homeostasis, which is regulated by astrocytes and secondarily affects myelin. In this Perspective, we argue that an immune attack on the ion and water homeostasis machinery in astrocytic endfeet, rather than directly on myelin, is the primary event in MS and that myelin damage is a consequence of astrocyte dysfunction. This hypothesis is supported by pathological studies on tissue from people with MS and has important implications for disease models and therapy targets.

MOGAD optic neuritis after mild head/orbital trauma in six children

Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is a potential cause of optic neuritis (ON). Its triggers and etiologies are not completely understood. We describe a novel clinical observation in six young patients with MOGAD-ON in the setting of strikingly parallel histories of mild head/orbital trauma. This is a single-center retrospective case series of six young patients and age-matched isolated MOGAD-ON controls. We present data both individually (de-identified, only the six trauma-associated cases) and in aggregate. Averages are presented as the arithmetic mean +/- SEM. 6/27 patients with MOGAD-ON, (3/6 female), between 8 and 18 years old presented with ON 5.5 days after mild head trauma. Four patients developed ON ipsilateral to their unilateral head trauma while two developed bilateral ON following midline head trauma. All patients tested positive for serum anti-MOG antibodies upon ON workup. They all received intravenous corticosteroids with rapid improvement in symptoms (5.5 weeks to full visual recovery) and none have since relapsed. No other patients with MOGAD-ON experienced preceding head trauma, and all patients in the control group were asked about trauma upon assessment of the history. Head trauma may serve as an inciting event in the presentation and diagnosis of MOGAD-ON. This novel observation provides a potential pathophysiologic mechanism independent of infectious triggers, although we cannot determine if these patients were already predisposed towards MOGAD-ON.

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.

Magnetic resonance imaging characteristics of myelin oligodendrocyte glycoprotein antibody positive patients -validation of current diagnostic criteria

BACKGROUND

Magnetic resonance imaging (MRI) features in the 2023 MOGAD International Panel diagnostic criteria help distinguish myelin oligodendrocyte glycoprotein (MOG) antibody disease (MOGAD) from mimics, particularly when MOG antibody titers are low. We evaluated the diagnostic performance of these MRI features in a large, previously diagnosed cohort.

METHODS

All MOG IgG cell-based assays performed by Mitogen Dx laboratory in Alberta from July 2017 to July 2023 were retrieved. All MOG positive with a MOGAD presentation and => one MRI study of brain, spine, or optic nerves were identified. MRIs were re-evaluated by two neuroradiologists and a neurologist for MOGAD-like features. Sensitivity, specificity, likelihood ratios, and positive and negative predictive value were calculated based on diagnosis in all patients and low antibody titer patients specifically.

RESULTS

Of 3831 tested patients, 158 had MOG antibodies, a MOGAD-consistent presentation, and MRI(s) of brain, spine or optic nerves. Of these 158 patients, 102 were diagnosed with MOGAD. Compared to patients with higher antibody titers, low titer patients with MOGAD MRI features had preserved specificity and improved negative predictive value for a MOGAD diagnosis. Only MOGAD patients had lesion resolution.

CONCLUSIONS

When applying MRI features from the 2023 MOGAD diagnostic criteria to an existing cohort, there was good sensitivity and specificity for MOGAD with improved specificity and negative predictive value in those with low antibody titers. The odds of a MOGAD diagnosis were high when lesions resolved on repeated imaging, particularly versus multiple sclerosis, suggesting this feature may merit more weight in future diagnostic criteria.

A child who suffered from HSV encephalitis and AE with positive anti-MOG results: a case report

OBJECTIVE

To investigate the clinical manifestations of a pediatric case involving herpes simplex virus (HSV) encephalitis concurrent with autoimmune encephalitis (AE), which is characterized by a positive anti-myelin oligodendrocyte glycoprotein (MOG) antibody status.

RESULTS

A 12-year-old girl initially presented with symptoms of autoimmune encephalitis, including weakness and poor appetite, followed by headache, dizziness, and personality changes, which are indicative of disease progression. Cerebrospinal fluid routine biochemical tests demonstrated abnormal results. Cerebrospinal fluid mNGS results demonstrated human herpesvirus type I, and autoimmune encephalitis antibody tests suggested a positive result for anti-myelin oligodendrocyte glycoprotein (MOG) antibodies (1:100). Brain MRI revealed abnormal signals in the bilateral frontal lobes and dorsal thalamus. Therefore, diagnoses of herpes simplex virus encephalitis and autoimmune encephalitis were determined. After treatment with acyclovir, gamma globulin and hormones, the patient exhibited significant improvement in her symptoms.

CONCLUSIONS

Children with herpes simplex virus encephalitis combined with autoimmune encephalitis may present with atypical clinical symptoms, and a positive anti-MOG antibody test is rarely observed, with no previous reports on this occurrence. The early detection of the relevant pathogens (in addition to timely reevaluation) can aid in accurate diagnosis. Moreover, antiviral and immunosuppressive therapy may significantly improve symptoms and patient prognosis.

Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD): Insights into pathogenesis and biomarkers of prognosis

MOG antibody-associated disease (MOGAD), an inflammatory demyelinating pathology, is typically associated with the clinical phenotypes acute disseminated encephalomyelitis (ADEM), optic neuritis (ON), or transverse myelitis (TM). The mainstay of diagnosis is detection of antibodies targeting oligodendrocyte-expressed MOG (MOG-IgG). MOG-IgG-mediated demyelination occurs via complement-dependent cytotoxicity (CDC), antibody-dependent cellular cytotoxicity (ADCC), enhanced cognate T-cell CNS infiltration and activation, and oligodendrocyte cytoskeleton disruption, but the exact role of the immune system in MOGAD is still poorly understood. The disease course is either monophasic or relapsing, with relapsing course affecting approximately two-thirds of individuals. Neurological disability accumulates with relapse and may manifest as visual, motor, sensory, and cognitive deficits. Thus, accurate disease course prediction is of paramount importance. Prognostic biomarkers, implemented at a global scale, have the potential to guide timely therapeutic decisions to limit relapse-associated disability accrual while simultaneously avoiding unnecessary immunosuppression in monophasic individuals. This review explores recent insights in the understanding of MOGAD pathogenesis as well as advances in prognostic biomarkers of relapsing course and disease activity.

The nomogram model predicts relapse risk in myelin oligodendrocyte glycoprotein antibody-associated disease: a single-center study

Background

Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is an autoimmune disorder of the central nervous system, characterized by seropositive MOG antibodies. MOGAD can present with a monophasic or relapsing course, where repeated relapses may lead to a worse prognosis and increased disability. Currently, little is known about the risk factors for predicting MOGAD relapse in a short period, and few established prediction models exist, posing a challenge to timely and personalized clinical diagnosis and treatment.

Methods

From April 2018 to December 2023, we enrolled 88 patients diagnosed with MOGAD at the First Hospital of Shanxi Medical University and collected basic clinical data. The data were randomly divided into a training cohort (80%) and a validation cohort (20%). Univariate logistic regression, least absolute shrinkage and selection operator (LASSO) regression and multivariate logistic regression were used to identify independent risk factors for 1-year relapse. A prediction model was constructed, and a nomogram was developed. The receiver operating characteristic (ROC) curve, calibration curve, and decision curve analysis (DCA) were used to evaluate and internally validate model performance.

Results

Among 88 MOGAD patients, 29 relapsed within 1 year of onset (33%). A total of 4 independent risk factors for predicting relapse were identified: female sex (P=0.040), cortical encephalitis phenotype (P=0.032), serum MOG antibody titer ≥1:32 (P=0.007), and immunosuppressive therapy after the first onset (P= 0.045). The area under curve (AUC) value of the nomogram prediction model constructed with these four factors was 0.866 in the training cohort, and 0.864 in the validation cohort. The cutoff value of the total nomogram score was 140 points, distinguishing the low relapse risk group from the high relapse risk group (P < 0.001). The calibration curve demonstrated high consistency in prediction, and the DCA showed excellent net benefit in the prediction model. Tested by ROC curve, calibration curve, and DCA, the nomogram model also demonstrates significant value in predicting MOGAD relapse within 2 years.

Conclusion

The nomogram model we developed can help accurately predict the relapse risk of MOGAD patients within one year of onset and assist clinicians in making treatment decisions to reduce the chance of relapse.

Central American and Caribbean consensus for the treatment of MS, NMOSD, and MOGAD

BACKGROUND

In recent years, significant progress has been made in immune demyelinating disorders, particularly regarding early diagnosis and disease-modifying drugs (DMDs). Despite advancements, socioeconomic factors in many Latin American countries present unique challenges that impede the proper identification and management of these disorders.

OBJECTIVES

The updated consensus from the Central American and Caribbean working group strives to enhance the management of Multiple Sclerosis (MS), Neuromyelitis Optica Spectrum Disorder (NMOSD), and Myelin Oligodendrocyte Glycoprotein Antibody-Associated Disease (MOGAD) by offering a framework for incorporating available treatment into clinical practice.

METHODS

The authors conducted an extensive bibliographic search and followed a consensus process that included input from forum members to present a new, revised, and finalized report.

RESULTS

The consensus, endorsed by over 70% of members, covers the application of DMDs, biologic agents, glucocorticoids, definitions of therapeutic failure, patient monitoring, cessation of treatment, prognosis, therapy use during pregnancy and lactation, and vaccination in patients initiating or on DMDs or biologic treatments.

CONCLUSION

The revised consensus and guidelines aim to enhance long-term outcomes in these regions by assisting patients, regulatory bodies, healthcare providers, and policymakers.

Evaluation of the predictive value of CSF-restricted oligoclonal bands on residual disability and risk of relapse in adult patients with MOGAD: MOGADOC study

BACKGROUND

The clinical course of myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD) is variable. However, robust markers of poor outcome and/or relapse risk are still missing.

OBJECTIVE

To evaluate the frequency of cerebrospinal fluid-restricted oligoclonal bands (CSF-OCB) in a national cohort of adult MOGAD patients and to assess their prognostic value for the risk of relapse and severity.

METHODS

We included MOGAD adult patients fulfilling the MOGAD 2023 criteria who underwent CSF analysis at maximum 3 months from onset.

RESULTS

Data from 190 patients were collected. We found the presence of CSF-OCB in 32 patients (16.8%). Positive and negative CSF-OCB patients were similar for median age at onset, sex, clinical presentation, severity at onset, and residual disability. Relapses were more frequent in the CSF-OCB+ group (p = 0.049), particularly within the first year of follow-up (p = 0.007). Although CSF-OCB+ was more frequently associated with imaging features suggestive of multiple sclerosis (MS) (p = 0.014), 78% of these patients fulfilled the 2023 supportive features and 65% experienced lesion vanishing at follow-up magnetic resonance imaging (MRI).

CONCLUSION

We found a higher risk of relapse in MOGAD with CSF-OCB particularly during the first year. Close attention is recommended regarding the risk of misdiagnosis with MS.

Pediatric MOG antibody-positive encephalitis with normal brain magnetic resonance imaging: a new spectrum associated with MOG antibodies?

Objective

To facilitate the accurate identification of clinical characteristics associated with myelin oligodendrocyte glycoprotein (MOG) antibody positive encephalitis in children presenting with normal brain magnetic resonance imaging (MRI) findings.

Method

Patients hospitalized at Children's Hospital of Chongqing Medical University from January 2016 to May 2024, who were positive for MOG antibodies and exhibited encephalitis symptoms with normal brain MRI findings, were retrospectively analyzed.

Results

A total of 17 patients (7 males and 10 females; mean age: 9.2 ± 2.8 years) were enrolled in the study. The most prevalent clinical symptoms were fever (17/17), with a median duration of 15 days (IQR: 7.5-21 days), headaches (17/17), mild alterations in mental status (17/17), seizures (6/17), vomiting (6/17), decreased binocular vision (2/17), and hemiplegia (1/17). The majority of cases (15/17) exhibited leukocytosis in peripheral blood (mean: 20.63 ± 7.09 × 109/L) accompanied by an elevated neutrophil ratio. C-reactive protein (CRP) and procalcitonin (PCT) levels were normal in 13 patients (13/17). Cerebrospinal fluid (CSF) leukocyte counts were elevated in all patients (median: 82/mm3; IQR: 49-155/mm3). Six patients (6/17) had elevated CSF protein levels (mean: 1.01 ± 0.38 g/L). CSF glucose levels were normal across all patients. Next-generation sequencing of CSF was performed in 10 patients, all yielding negative results. All patients had a serum MOG antibodies titer of ≥1:32, and six children (6/17) had a CSF MOG antibody titer of ≥1:32. All patients showed clinical improvement after immunotherapy. Only one patient (1/17) experienced a relapse.

Conclusion

For patients presenting with encephalitis and normal brain MRI findings, early testing for anti-MOG antibody should be considered if they exhibit the following characteristics: (1) persistent fever; (2) elevated peripheral blood white blood cell (WBC) counts, with normal or slightly elevated PCT and CRP levels; (3) mild elevation of CSF WBC counts, normal or mildly elevated protein levels, and normal CSF glucose levels; and (4) ineffectiveness of antibiotic or antiviral therapy. Encephalitis with normal brain MRI may be regarded as a potential new spectrum associated with MOG antibodies, meriting additional exploration and consideration.

Clinical and imaging features and treatment response of anti-NMDAR encephalitis combined with MOGAD

BACKGROUND

To investigate the clinical, imaging features, immunotherapy of anti-N-methyl-D-aspartate receptor encephalitis (NMDARE) combined with myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD).

METHODS

A total of 124 patients with NMDARE and 86 patients with MOGAD were screened from an ongoing prospective cohort study (Clinical and Imaging Patterns of Neuroinflammation Diseases in China, CLUE). Ten NMDARE combined with MOGAD patients, were finally enrolled in this study. Clinical and imaging data and follow-up results characteristics were collected and analyzed.

RESULTS

In these 10 patients with NMDARE combined with MOGAD, 7 patients (70 %) showed recurrent courses. In all 26 episodes, 14 episodes (53.8 %) showed encephalitis-related symptoms, 6 episodes (23.1 %) showed demyelination-related symptoms, 6 episodes (23.1 %) showed both. The median CSF leukocytes were 13/μL (range 1-413) and the median protein was 0.43 g/L (range 0.22-0.70). MRI lesions were found involving the optic nerve (2/10), spinal cord (3/10), deep gray matter (3/10), cortex (6/10), subcortex (7/10), brainstem (5/10) and cerebellum (4/10). Leptomeningeal enhancement was found in 3 patients. All patients received high-dose intravenous methylprednisolone and immunoglobulin therapy during attacks. Seven patients received rituximab (RTX). The median annualized recurrence rate (ARR) reduced significantly following RTX treatments (z = -2.201, p = 0.028), and achieved good outcomes at the last follow-up visit (modified Rankin scale score ≤ 2).

CONCLUSION

NMDARE combined with MOGAD represents a unique characteristic of autoantibody-mediated encephalitis. Coexistence of NMDAR and MOG antibody may indicate high recurrence risk. RTX may be a relatively efficient therapeutic option.

Assessment of neuronal and glial serum biomarkers in myelin oligodendrocyte glycoprotein antibody-associated disease: the MULTIMOGAD study

BACKGROUND

Serum neurofilament light chain (sNfL) and serum glial fibrillary acidic protein (sGFAP) have emerged as important biomarkers in multiple sclerosis (MS) and aquaporin-4 seropositive neuromyelitis optica spectrum disorder (AQP4-NMOSD). However, their interest in myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) remains unclear. Our aim was to characterise sNfL and sGFAP profile and analyse their usefulness in predicting relapses and disability in MOGAD.

METHODS

Retrospective study of adult MOGAD patients with serum samples collected at baseline (≤3 months from disease onset) and follow-up (>6 months from baseline sample). sNfL and sGFAP were analysed using Simoa HD-1, and values were compared across time-points. The association between biomarkers and clinical variables and their predictive value for disability and relapses were analysed.

RESULTS

Eighty-nine MOGAD patients were included. Baseline sNfL and sGFAP values were high at baseline and decreased over time (p<0.001, p=0.027, respectively). sNfL and sGFAP values were associated with Expanded Disability Status Scale (EDSS) at attacks (β 0.15 (0.06; 0.25), p=0.002; β 0.14 (0.07; 0.21), p<0.001, respectively) and were lower in optic neuritis presentations (β -0.69 (-1.18; -0.19), p=0.007; β -0.42 (-0.76; -0.08), p=0.016). Biomarker deltas[Δ] (baseline values - second samples values) were associated with ΔEDSS (initial EDSS - final EDSS) (ΔsNfL β 0.52 (0.01; 1.04), p=0.046; ΔsGFAP β 1.07 (0.38; 1.75), p=0.003). Finally, sNfL values independently predicted the risk of relapses (HR 2.06 (1.41; 3.01), p<0.001).

CONCLUSIONS

Our results on sNfL and sGFAP suggest initial neuro-axonal and astrocytic damage in MOGAD and the utility of these biomarkers at onset and follow-up in predicting clinical recovery and relapses.

Assessing the inflammation in pediatric MOGAD: Significance of CSF HMGB1 and related biomarkers

Background and purpose

Myelin-oligodendrocyte glycoprotein antibody associated disease (MOGAD) is a common inflammatory disease of the central nervous system (CNS) in children that can lead to demyelination. Evaluation and monitoring of biomarkers associated with its pathogenesis would provide vital information on disease progression and therapeutic assessment.

Methods

We assessed NLRP3, HMGB1, IL-6, and IL-33 levels in the cerebrospinal fluid (CSF) of pediatric patients with MOGAD at different time points and their association with the risk of disease. We recruited 30 patients with MOGAD (20 in the acute phase and 10 in remission) and 10 control patients with noninflammatory demyelinating disease. The expanded disability status scale (EDSS) was used to assess disease severity.

Results

NLRP3, HMGB1, and IL-6 levels in the CSF were significantly higher in patients with MOGAD during the acute phase than in remission (P < 0.05, P < 0.05, P < 0.05) and the control group (P < 0.01, P < 0.0001, P < 0.01). HMGB1 levels were significantly correlated with NLRP3 levels (P < 0.01) during the acute phase. Moreover, we found notable correlation between HMGB1 levels and EDSS (P < 0.05) scores. IL-6 levels were significantly correlated with the total number of attacks (P < 0.05), but not with EDSS scores.

Conclusions

These findings suggest that NLRP3, HMGB1, and IL-6 in the CSF may be potential therapeutic targets and are at least partly involved in the pathogenesis of pediatric MOGAD. HMGB1 in the CSF may be a potential biomarker correlating with pediatric MOGAD severity. Further investigations are warranted to validate potential cytokine pathways between that NLRP3, HMGB1, and IL-6 of MOGAD.

Pseudotumoural optic neuritis in myelin oligodendrocyte glycoprotein antibody-associated disease in children: Pseudotumoural optic neuritis in MOG antibody-associated disease

Myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD) is a neuro-inflammatory condition affecting adults and children. The presentations vary and include acute disseminated encephalomyelitis, optic neuritis or transverse myelitis. Optic neuritis associated with anti-MOG antibodies is typically bilateral, anterior and initially severe but usually resolves quickly and completely. Here, we describe 3 children with pseudotumoural optic neuritis associated with anti-MOG antibodies and their outcome. Recognizing these unusual presentations may reduce unnecessary work-ups and improve functional prognosis by implementing rapid and adequate treatment.

Mild Malformation of Cortical Development With Oligodendroglial Hyperplasia and Epilepsy: A Systematic Review

Background and Objectives

Mild malformation of cortical development with oligodendroglial hyperplasia and epilepsy (MOGHE) is a newly described rare entity of drug-resistant epilepsy, with a wide spectrum of presentations. We aim to describe the diagnostic features and prognosis of MOGHE in a large cohort.

Methods

We performed a systematic review preregistered on PROSPERO (CRD42023472978), in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. We searched PubMed, Embase, Scopus, and ScienceDirect between database inception and November 30, 2023, for all published studies on MOGHE. Inclusion criteria were a histopathologic diagnosis of MOGHE. The risk of bias was analyzed with a standardized tool specifically for case reports and case series. The demographic, clinical, EEG, neuroimaging, genetic, and neuropathologic features; treatments; and prognosis were extracted and analyzed. Subgroup analysis was performed with the age at onset and SLC35A2 variant status.

Results

A total of 163 patients with MOGHE from 18 studies were included in the analysis. The median age at seizure onset was 1.2 years, and 103 were male. Ninety-five patients presented with unilobed lesions. Ninety-nine had lesions in the frontal lobe. A total of 101 patients achieved a favorable surgical outcome. Patients with an onset before 10 years were more likely to present with epileptic spasms, the West syndrome, a circumscribed pattern of interictal EEG, intellectual disabilities, and a better seizure outcome, compared with those with an onset age 10 years and older. Forty-five patients (72.6%) were SLC35A2-positive. Patients harboring the SLC35A2 variants were more likely to present as Lennox-Gastaut syndrome, when compared with those who were SLC35A2-negative.

Discussion

MOGHE is a distinct entity of drug-resistant epilepsy associated with SLC35A2 variants, characterized by age-dependent phenotypes. The study emphasizes the clinical pearls indicative of the rare disease, which may facilitate early recognition and appropriate selection of treatments. The included studies were case reports or series, which were mainly limited by selection and reporting biases.

Association of peripapillary retinal nerve fiber layer atrophy with cognitive impairment in patients with neuromyelitis optica spectrum disorder

BACKGROUND

We aimed to explore the association between peripapillary retinal nerve fiber layer thickness (pRNFL), macular ganglion cell-inner plexiform layer (mGCIPL), and cognitive impairment (CI) in patients with neuromyelitis optica spectrum disorder (NMOSD).

METHOD

In this cross-sectional study, 38 (28 aquaporin-4 (AQP4) IgG-seropositive) NMOSD patients and 20 healthy controls (HC) underwent cognitive assessment using Minimal Assessment of Cognitive Function in Multiple Sclerosis (MACFIMS) battery. Spectral-domain optical coherence tomography (OCT) was performed for both eyes of all NMOSD patients. First, we examined the association of pRNFL and mGCIPL with cognitive function in all patients, regardless of the history of previous optic neuritis (ON). We then included only eyes without a prior history of ON, incorporating non-ON eyes in patients with unilateral ON and the average of OCT measures for both non-ON eyes in patients without a history of ON.

RESULTS

Sixteen (42.1%) NMOSD patients exhibited global CI. There was a significant decrease in pRNFL (Δ: 24.33 μm, p = 0.002) and mGCIPL (Δ: 9.20 μm, p = 0.009) in NMOSD patients with CI compared to those without. The atrophy of pRNFL showed an inverse association with CI before (OR = 1.059, 95% CI: 1.015, 1.105) and after adjustment for age, sex, and disease duration (OR = 1.072, 95%CI: 1.009, 1.139). An inverse significant association was observed between mGCIPL atrophy and CI before adjustment (OR = 1.102, 95% CI: 1.017, 1.194), but not after adjustment (OR = 1.106, 95%CI: 0.999, 1.224). After narrowing our analysis to non-ON eyes, the same results for pRNFL and CI were observed (unadjusted: OR = 1.054, 95% CI: 1.004, 1.106; adjusted: OR = 1.081, 95%CI: 1.000, 1.168). There was no significant association found between mGCIPL thickness and CI in both unadjusted and adjusted models. In sensitivity analyses, we observed no significant association between pRNFL and mGCIPL with CI in AQP-IgG-seropositive NMOSD patients.

CONCLUSION

This study, for the first time, provide a preliminary evidence for a possible relation between pRNFL atrophy and occurrence of cognitive impairment in NMOSD patients. Further studies are required to explore the possible association of OCT parameters with cognition function in NMOSD patients.

A roadmap to increasing access to AQP4-Ig testing for NMOSD: expert recommendations

The discovery of aquaporin 4 immunoglobulin G (AQP4-IgG) autoantibody, present in ∼80% of patients with neuromyelitis optica spectrum disorder (NMOSD), dramatically improved its diagnosis, treatment, and prognosis. While Brazil has a higher prevalence of NMOSD (up to 4.5 per 100,000 people) compared with global averages, disparities in access to testing in Brazil impede early diagnosis and treatment. To tackle these issues, the Americas Health Foundation convened a three-day virtual conference with six Brazilian NMOSD experts. This paper emphasizes the importance of addressing the gaps in physicians' knowledge about NMOSD. Stakeholders, including government agencies, should develop national programs for continuing medical education. The public healthcare system should ensure the availability and accessibility of AQP4-IgG antibody testing. Clinical practice guidelines for NMOSD diagnosis and treatment must be established. Such guidelines will enable healthcare providers to manage patients promptly after the initial attack, reducing relapses and improving quality of life. Finally, addressing the fragmented healthcare system, including bridging the gap between public and private institutions and improving access to telemedicine, will aid individuals in Brazil with NMOSD in receiving early diagnosis and treatment. NMOSD presents unique challenges in Brazil because of its higher prevalence and limited access to crucial AQP4-IgG tests. Overcoming these challenges requires collaboration among experts, healthcare providers, government agencies, and the public healthcare system to improve diagnosis, treatment, and patient outcomes.

Pain and Headache in Myelin Oligodendrocyte Glycoprotein Antibody-Associated Disease

PURPOSE OF REVIEW

The purpose of this review is to evaluate the current knowledge and recent findings on different pain and headache presentations associated with Myelin Oligodendrocyte Glycoprotein Antibody-Associated Disease (MOGAD) disease.

RECENT FINDINGS

MOGAD is an inflammatory autoimmune disease affecting mostly the central nervous system, presenting with optic neuritis, transverse myelitis and other forms of inflammatory demyelination. Pain and headache in MOGAD have been recognized more recently and acute and chronic forms of pain can occur in both the adult and pediatric population. An important recent observation is that MOGAD can affect the peripheral nervous system, which can contribute to pain symptoms. Acute and chronic forms of pain have been described in MOGAD, including ocular pain, different types of headaches and neuropathies, involving the central and peripheral nervous system. Awareness of these types of pain in both the pediatric and adult population is crucial, to ensure timely diagnosis and treatment.

From diagnosis to treatment: exploring the mechanisms underlying optic neuritis in multiple sclerosis

Multiple sclerosis (MS) is a chronic autoimmune disease affecting the central nervous system, commonly causing sensory disturbances, motor weakness, impaired gait, incoordination and optic neuritis (ON). According to the statistics, up to 50% of MS patients experience vision problems during the disease course, suffering from blurred vision, pain, color vision deficits, and even blindness. Treatments have progressed from corticosteroids to therapies targeted against B/T cells. This review comprehensively and systematically reappraises the diagnostic methods for visual impairment in MS patients. It also summarizes the most recent treatment approaches and effective medications for ON in MS. Finally, we examine the immunoinflammatory mechanisms that underlie lesions in the central nervous system in multiple sclerosis, in order to direct future investigations to confirm these mechanisms in the visual pathway.

MOGAD: A comprehensive review of clinicoradiological features, therapy and outcomes in 4699 patients globally

Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is one of the most common antibody-mediated CNS disorders. Optimal diagnostic and prognostic biomarkers remain unclear. Our aim was to clarify these biomarkers and therapeutic outcomes internationally. We reviewed articles from 2007 to 2022 and identified 194 unique cohorts encompassing 4699 paediatric and adult patients from 31 countries. Where phenotypes were specified, the most common initial presentation overall was optic neuritis (ON; paediatric 34 %; adults 60 %), during which 71 % had papilloedema on fundoscopy. The most common phenotype at latest follow-up was relapsing ON (20 %). Only 47 % of patients with 6-24 months of follow-up exhibited a relapsing course, while this proportion was much higher (72 %) when follow-up was extended beyond 5 years. Despite a similar relapse rate, the time to first relapse was much shorter in paediatric than adult patients (6 vs 17 months). Adult MRI-Brain scans performed at onset were more frequently normal than in paediatric patients (50 % vs 27 %). Abnormal MRI scans showing involvement of deep grey matter, cortico-subcortical, periventricular lesions, leptomeningeal enhancement, H-shaped spinal cord lesions, and bilateral optic nerve abnormalities were more common in paediatric patients compared to adults. Conversely, adults demonstrated higher frequencies of eccentric spinal cord lesions and intraorbital involvement. CSF analysis demonstrated intrathecally restricted oligoclonal bands in 12 %, elevated protein in 35 %, and pleocytosis in 54 %. Peripapillary retinal nerve fibre layer (pRNFL) thickness, measured acutely, frequently demonstrated swelling (weighted-median 145 μm; normal 85-110). Most cohorts demonstrated notable pRNFL atrophy at latest follow-up (weighted-median 67 μm). pRNFL thickness was significantly lower when measured at or after six months following ON onset, compared to measurements taken within the first six months following ON onset (p < 0.001). Therapeutic and outcome data was available for 3031 patients with a weighted-median disease duration of 32 months. Acute immunotherapy was initiated in 97 %, and maintenance immunotherapy in 64 %, with considerable regional variation. Expanded Disability Status Scale (EDSS) scores and visual acuities improved from nadir to latest follow-up in most patients. A negative correlation was noted between follow-up pRNFL thickness and latest follow-up visual acuity (r = -0.56). Based on this unprecedented global aggregation of MOGAD patients, we reveal a higher proportion of relapsing patients than previously recognised. While commonly used measures like EDSS show significant recovery, they underestimate visual disability following optic neuritis, the most frequent clinical presentation. Our findings suggest that RNFL thickness, especially when measured at least 6 months post-ON, may serve as a more sensitive biomarker for long-term visual impairment.

Distinct clinical patterns in AQP4-IgG- positive NMOSD patients vs. Seronegative: Insights from a single-center study in Argentina

BACKGROUND

Distinct clinical course patterns have been identified between AQP4-IgG-positive and AQP4-IgG-negative NMOSD patients.

OBJECTIVES

This study aimed to evaluate the differences between AQP4-IgG-seropositive and AQP4-IgG-seronegative NMOSD patients in a single centre in Argentina.

METHODS

We performed a retrospective cross-sectional study of 108 NMOSD patients in the city of Buenos Aires, Argentina.

RESULTS

We selected 94 for analysis. 77 patients (82 %) were AQP4-IgG positive. In the AQP4-IgG positive group, the ratio of male to female was 1:10 vs. 1:1.2 in the seronegative group (p = 0.001). Relapses were observed in 76 out of 77 (99 %) AQP4-IgG positive patients versus 3 out of 17 (17.6 %) AQP4-IgG negative patients (p = 0.01). In the seropositive group, other autoimmune diseases were present in 34/77 patients (44 %) vs. 2/12 (12 %) in the seronegative patients, a statistically significant difference (p = 0.009). 81 % of the seropositive group had an early adulthood onset (EAO-NMOSD) compared to 35 % in the seronegative group. All AQP4+ patients positive received treatment with monoclonal antibodies. In AQP4-IgG- NMOSD patients the use of immunosuppressive treatment was more common.

CONCLUSION

Female predominance, EAO-NMOSD, recurrence course and a high prevalence of autoimmune disease in AQP4-IgG-positive patients demonstrated a more pronounced autoimmunity profile.

Human microbiome-derived peptide affects the development of experimental autoimmune encephalomyelitis via molecular mimicry

BACKGROUND

Gut commensal microbiota has been identified as a potential environmental risk factor for multiple sclerosis (MS), and numerous studies have linked the commensal microorganism with the onset of MS. However, little is known about the mechanisms underlying the gut microbiome and host-immune system interaction.

METHODS

We employed bioinformatics methodologies to identify human microbial-derived peptides by analyzing their similarity to the MHC II-TCR binding patterns of self-antigens. Subsequently, we conducted a range of in vitro and in vivo assays to assess the encephalitogenic potential of these microbial-derived peptides.

FINDINGS

We analyzed 304,246 human microbiome genomes and 103 metagenomes collected from the MS cohort and identified 731 nonredundant analogs of myelin oligodendrocyte glycoprotein peptide 35-55 (MOG35-55). Of note, half of these analogs could bind to MHC II and interact with TCR through structural modeling of the interaction using fine-tuned AlphaFold. Among the 8 selected peptides, the peptide (P3) shows the ability to activate MOG35-55-specific CD4+ T cells in vitro. Furthermore, P3 shows encephalitogenic capacity and has the potential to induce EAE in some animals. Notably, mice immunized with a combination of P3 and MOG35-55 develop severe EAE. Additionally, dendritic cells could process and present P3 to MOG35-55-specific CD4+ T cells and activate these cells.

INTERPRETATION

Our data suggests the potential involvement of a MOG35-55-mimic peptide derived from the gut microbiota as a molecular trigger of EAE pathogenesis. Our findings offer direct evidence of how microbes can initiate the development of EAE, suggesting a potential explanation for the correlation between certain gut microorganisms and MS prevalence.

FUNDING

National Natural Science Foundation of China (82371350 to GY).

Neuroglia in autoimmune encephalitis

Neuroglial cells play a crucial role in central nervous system (CNS) health and disease. Antibody-associated autoimmune encephalitis (AE) represents a group of inflammatory brain diseases with antibodies (Abs) against neuronal cell surface (e.g., anti-N-methyl-d-aspartate receptor (NMDAR), anti-leucine-rich glioma-inactivated 1 (LGI1), γ-aminobutyric acid (GABA) type A or B receptor (GABAA/BR)) or intracellular neuronal proteins. AE with Abs against glial antigens, e.g., myelin oligodendrocyte glycoprotein (MOG), glial fibrillary acidic protein (GFAP) are also described. Besides the known pathomechanisms with direct pathogenic effects of primary neuronal Abs and activation of innate (dendritic cells) and adaptive (B and T cells) immune systems, research findings suggest the involvement of glial cells including astrocytes, microglia, oligodendrocytes in the pathogenesis of Ab-associated AE, but only a limited number of studies is available. Neuropathologic findings showed reactive astrogliosis and microgliosis with microglial activation/proliferation, e.g., in anti-NMDAR and anti-LGI1 encephalitis. Direct effects of the GABAAR and NMDAR Abs on astrocytic receptors are discussed. Because of the primary involvement of B and T cells in the pathogenesis of Ab-associated AE it can be assumed that astrocytic and microglial activation is largely a response to the primary changes, but additional direct effects of Abs on astrocytic receptors are possible. Further research in this field is required to explore the exact role of glial cells in Ab-associated AE.

Complement Activation Profiles Predict Clinical Outcomes in Myelin Oligodendrocyte Glycoprotein Antibody-Associated Disease

BACKGROUND AND OBJECTIVES

The role of the complement system in myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is not completely understood, and studies exploring its potential utility for diagnosis and prognosis are lacking. We aimed to investigate the value of complement factors (CFs) as diagnostic and prognostic biomarkers in patients with MOGAD.

METHODS

Multicentric retrospective cohort study including patients with MOGAD, multiple sclerosis (MS) and aquaporin-4 seropositive neuromyelitis optica spectrum disorder (AQP4-NMOSD) with available paired serum and CSF samples. A panel of CFs were measured by multiplex ELISA, and the levels were compared between the 3 conditions. Univariable and multivariable analyses were performed to evaluate the association between levels of CFs and relapse and disability outcomes in MOGAD patients.

RESULTS

Ninety-four patients (MOGAD, n = 60; MS, n = 18; AQP4-NMOSD, n = 16) were included. Mean (SD) age at sampling was 39.4 (16.7), 40.7 (7.0), and 43.3 (21.0), respectively. Female were predominant, especially in AQP4-NMOSD (88%). Combination of the serum levels of C3a, C4a, and C3a/C3 ratio showed excellent potential to discriminate MOGAD from patients with MS (area under the curve [AUC] [95% CI] 0.95 [0.90-0.99]) and from AQP4-NMOSD (AUC 0.88 [0.76-1.00]). In patients with MOGAD, CSF levels of CFs of the classical/lectin pathway influenced relapse-related outcomes, and lower C4 levels were associated with higher number of relapses during follow-up (incidence rate ratio [95% CI] 0.88 [0.78-0.99]; p = 0.04 in multivariable analysis), and a high C4a/C4 ratio was associated with increased risk of second relapse during the first year (hazard ratio [95% CI] 3.68 [1.26-10.78]; p = 0.02 in multivariable analysis). Time to second relapse was shorter in patients with MOGAD with a high CSF C4a/C4 ratio (log-rank p = 0.01). CSF levels of the membrane attack complex SC5b9 influenced disability-related outcomes, and baseline CSF SC5b9 levels were higher in patients who reached the final Expanded Disability Status Scale (EDSS) ≥ 3.0 (p = 0.002), and elevated SC5b9 levels were associated with increased risk of reaching EDSS ≥ 3.0 (odds ratio [95% CI] 1.79 [1.16-3.67]; p = 0.04 in multivariable analyses).

DISCUSSION

Our results suggest that serum and CSF levels of CFs have diagnostic and prognostic value respectively in patients with MOGAD. These findings support the use of complement inhibitors as a therapeutic approach in these patients.

Disease-modifying treatments for neuromyelitis optica spectrum disorder in the context of a new generation of biotherapies

Neuromyelitis optica spectrum disorder (NMOSD) is a rare but debilitating autoimmune disease of the central nervous system (CNS) for which several biotherapies have recently been approved on the market. Historically, NMOSD disease-modifying treatments relied on wide-spectrum off-label immunosuppressants, such as azathioprine, mycophenolate mofetil, and cyclophosphamide. Since 2015, evidence has accumulated to support off-label biotherapies (rituximab and tocilizumab) and to approve satralizumab, inebilizumab, eculizumab, and ravulizumab. This next generation of drugs provides several targeted disease-modifying treatment options for NMOSD. Here, we review this modern panel. We first review the mechanistic rationales associated with their specific targets. We then review the pivotal evidence supporting their use in practice and their respective regimens. Lastly, we discuss the positioning of each therapeutic class. The current therapeutic options in NMOSD comprise three targeted mechanisms at different stages of a unique tissue-injury cascade: B-cell depleting, anti-cytokine, and anti-complement therapies. One drug has been approved on the market in each class. The current consensus proposes positioning the approved drugs as first-line treatments for newly-diagnosed patients and as alternative therapies in case of failure of historical treatment. Yet, there has been limited acceptance in practice due to high drug prices.

MOG IgG antibody positivity from laboratory to clinical practice: A real world experience

BACKGROUND AND OBJECTIVES

Myelin oligodendrocyte glycoprotein (MOG) associated disease (MOGAD) is an antibody-mediated inflammatory demyelinating disorder of the CNS with varied presentations like optic neuritis (ON), transverse myelitis, and cortical encephalitis. This study aims to highlight the significance of low MOG IgG antibody positivity and its diagnostic implications in a real-world cohort.

METHODS

In this retrospective observational study, serum and CSF from suspected MOGAD cases were tested at a tertiary healthcare centre's Neuroimmunology Laboratory. MOG autoantibodies were detected using a EUROIMMUN commercial kit, and seropositivity was determined by visual agreement of fluorescence by two trained observers. Patient data were retrieved from Electronic Medical records.

RESULTS

Out of 103 MOG IgG seropositive patients, 95 were included in the final analysis (Mean age: 32.47±4.63 years; 42 males, 53 females; 36 pediatric, 59 adult) after excluding those with alternate diagnoses. The most common clinical event was ON (37.89%). The 2023 International MOGAD Diagnostic Criteria was met by 35/67 low-strength and 27/28 high-strength patients. Adults were more likely to have atypical presentations and low serum MOG levels. Pediatric patients had better EDSS at discharge but relapsed more. There were no significant differences between low and high positive groups in terms of treatment received, EDSS, relapse, or outcome.

DISCUSSION

Low and high levels of MOG seropositivity showed similar diagnostic value in terms of clinical features, treatment outcome, and prognosis, except for age distribution. Many patients exhibited low-strength positivity and atypical disease presentations, requiring strong clinical judgement for diagnosis.

Epidemiology of optic disc edema in 2021/2022: Results from a cohort of 197 patients

OBJECTIVE

The aim of our study was to determine the etiologies of optic disc edema between 2021 and 2022.

MATERIALS AND METHODS

This was a multicentric study at the Timone and Nord university hospitals in Marseille. Patients were retrospectively followed in ophthalmology departments, with inclusion between January 2021 and December 2022. All patients presenting with newly diagnosed uni- or bilateral optic disc edema, both adults and children, were included. Their ophthalmological evaluation included a fundus examination and optical coherence tomography if feasible.

RESULTS

In total, 197 patients were included. Intracranial hypertension (IH) was the most frequent etiology (37.06%). The primary causes of IH were idiopathic (27/73), intracranial tumors (21/73), and cerebral venous thrombosis (12/73). The second etiology of optic disc edema was retinal vein occlusion in 19.9% of cases (39/197). Edema reactive to uveitis was found in 13.2% of cases (26/197). Finally, inflammatory (17/197) and ischemic (30/197) optic neuropathies were identified.

CONCLUSION

This study updates the most frequent etiologies of optic disc edema in 2021 and 2022 to facilitate diagnostic hypotheses for de novo optic disc edema. It highlights the importance of a comprehensive and personalized evaluation in diagnosing optic disc edema, taking into account recent advances in imaging techniques and biomarkers.

Uveitis: A snapshot in the MOG antibody spectrum

Despite the commonly observed association of anti-myelin oligodendrocyte glycoprotein (MOG) antibodies with bilateral optic neuritis, their connection to uveitis is largely unexplored. The presented case involves a 41-year-old male with uveitis and bilateral optic neuritis, subsequently diagnosed with myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD). This case, characterized by bilateral optic neuritis associated to anti-MOG antibodies and the concurrent onset of unilateral anterior uveitis, provides further evidence concerning the features of intraocular inflammation in MOGAD. The patient's treatment response, including the use of rituximab due to contraindications to oral steroids, emphasizes the importance of personalized management strategies in MOGAD-associated ocular manifestations.

Visual quality of life in NMOSD and MOGAD: profiles, dynamics and associations with ageing and vision

OBJECTIVE

In this multicentric study, we were interested in the vision-related quality of life and its association with visual impairment in neuromyelitis optica spectrum disorders (NMOSD) and myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) in comparison to multiple sclerosis (MS) and healthy controls.

METHODS

We analysed extracted data from the German NEMOS registry including National Eye Institute Visual Function Questionnaire (NEI-VFQ) scores, high and low contrast visual acuity (HCVA, LCVA), visually evoked potentials (VEP) and the scores for the expanded disability status scale (EDSS) and other neurological tests which assessed their disease-related impairment. The mean follow-up time of our patients was 1.2 years. We used adjusted linear mixed effect models to analyse NEI-VFQ differences and interactions with visual acuity among NMOSD, MOGAD, a matched MS cohort and healthy controls.

RESULTS

Despite a younger age in the MOGAD cohort (39 y.o.), vision and socioemotional-related quality of life reduction was similar over all patient subgroups in comparison to healthy controls. The most impacted life quality dimension was general health, followed by general vision, driving and role difficulties. Decline in some of the NEI-VFQ subscales scores is mostly predicted by age. The HCVA was the best predictor for most of the subscales of the NEI-VFQ.

DISCUSSION

Despite important age differences, NMOSD, MOGAD and MS seem to share a rather similar perception on their vision and quality of life impairment, which is overall poorer than that of healthy controls.

Pediatric Neuroimaging of Multiple Sclerosis and Neuroinflammatory Diseases

Using a pediatric-focused lens, this review article briefly summarizes the presentation of several demyelinating and neuroinflammatory diseases using conventional magnetic resonance imaging (MRI) sequences, such as T1-weighted with and without an exogenous gadolinium-based contrast agent, T2-weighted, and fluid-attenuated inversion recovery (FLAIR). These conventional sequences exploit the intrinsic properties of tissue to provide a distinct signal contrast that is useful for evaluating disease features and monitoring treatment responses in patients by characterizing lesion involvement in the central nervous system and tracking temporal features with blood-brain barrier disruption. Illustrative examples are presented for pediatric-onset multiple sclerosis and neuroinflammatory diseases. This work also highlights findings from advanced MRI techniques, often infrequently employed due to the challenges involved in acquisition, post-processing, and interpretation, and identifies the need for future studies to extract the unique information, such as alterations in neurochemistry, disruptions of structural organization, or atypical functional connectivity, that may be relevant for the diagnosis and management of disease.

Predictors of a relapsing course in myelin oligodendrocyte glycoprotein antibody-associated disease

BACKGROUND

Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is a recently described demyelinating disorder, and children represent about 50% of all cases. Almost half of the patients experience relapses, but very few studies have evaluated predictors of relapse risk, challenging clinical management. The study aimed to identify predictors at MOGAD onset that are associated with a relapsing course.

METHODS

Prospectively collected data from paediatric patients with MOGAD seen by the US Network of Paediatric MS Centres were leveraged. Univariable and adjusted multivariable models were used to predict recurrent disease.

RESULTS

We identified 326 MOGAD cases (mean age at first event 8.9 years [SD 4.3], 57% female, 77% white and 74% non-Hispanic) and 46% relapsed during a mean follow-up of 3.9 years (SD 4.1). In the adjusted multivariable model, female sex (HR 1.66, 95% CI 1.17 to 2.36, p=0.004) and Hispanic/Latino ethnicity (HR 1.77, 95% CI 1.19 to 2.64, p=0.005) were associated with a higher risk of relapsing MOGAD. Maintenance treatment initiated before a second event with rituximab (HR 0.25, 95% CI 0.07 to 0.92, p=0.037) or intravenous immunoglobulin (IVIG) (HR 0.35, 95% CI 0.14 to 0.88, p=0.026) was associated with lower risk of a second event in multivariable analyses. Conversely, maintenance steroids were associated with a higher estimated relapse risk (HR 1.76, 95% CI 0.90 to 3.45, p=0.097).

CONCLUSION

Sex and ethnicity are associated with relapsing MOGAD. Use of rituximab or IVIG therapy shortly after onset is associated with a lower risk of the second event. Preventive treatment after a first event could be considered for those with a higher relapse risk.

Efficacy and safety of tocilizumab treatment in refractory MOG-IgG related optic neuritis

Background

Myelin oligodendrocyte glycoprotein (MOG) IgG related optic neuritis (ON) which manifests as recurrent episodes and severe visual impairment remains a challenging issue in relapse prevention. Tocilizumab (TCZ), a human monoclonal antibody against IL-6R, may be an alternative treatment for the prevention of relapse in refractory MOG-ON patients.

Objectives

To investigate the efficacy and safety of Tocilizumab (TCZ) in patients with recurrent myelin oligodendrocyte glycoprotein IgG related optic neuritis (MOG-ON).

Design

We conducted an open-label, single-arm, nonrandomized, uncontrolled clinical trial at a tertiary neuro-ophthalmology center between April 1, 2021, and April 1, 2022.

Methods

Participants with relapsed MOG-ON, whose disease had been resistant to previous immunotherapies, received tocilizumab as monotherapy or as an add-on therapy and were followed up for at least 12 months. Annual recurrence rate (ARR), best corrected visual acuity (BCVA), and adverse events were recorded for analyses.

Result

Ten patients (7 females and 3 males) with relapsed MOG-ON were included with a mean (SD) ages of 28.6 (20.5) years old at disease onset and 30.9 (19.7) years at first TCZ administration, with a mean disease duration of 26.6 (11.3) months. Seven (70%) patients remained relapse-free, and the median (range) ARR dropped significantly from 1.9 (0.4-3.5) to 0.0 (0-4.0) during TCZ treatment (p = 0.006). Three patients experienced a relapse of ON at 2, 3, and 7 months after TCZ therapy. The median BCVA improved from 2.7 (2.0-3.0) logMAR at the nadir to 0.2 (0-2.0) logMAR at the last follow-up. Adverse effects included transient diarrhea (n = 1) and upper respiratory infection (n = 1).

Conclusion

This study supports that Tocilizumab therapy, with or without concomitant immunosuppression, is safe and effective in reducing relapses in MOG-ON patients who have failed immunosuppressive therapy or targeted B-cell therapy.

Trial registration

This trial is registered with the Chinese Clinical Trial Registry, number ChiCTR2100045273. (URL: https://www.chictr.org.cn/showproj.html?proj=124810).

Turncoat antibodies unmasked in a model of autoimmune demyelination: from biology to therapy

Autoantibodies contribute to many autoimmune diseases, yet there is no approved therapy to neutralize them selectively. A popular mouse model, experimental autoimmune encephalomyelitis (EAE), could serve to develop such a therapy, provided we can better understand the nature and importance of the autoantibodies involved. Here we report the discovery of autoantibody-secreting extrafollicular plasmablasts in EAE induced with specific myelin oligodendrocyte glycoprotein (MOG) antigens. Single-cell RNA sequencing reveals that these cells produce non-affinity-matured IgG antibodies. These include pathogenic antibodies competing for shared binding space on MOG's extracellular domain. Interestingly, the synthetic anti-MOG antibody 8-18C5 can prevent the binding of pathogenic antibodies from either EAE mice or people with MOG antibody disease (MOGAD). Moreover, an 8-18C5 variant carrying the NNAS mutation, which inactivates its effector functions, can reduce EAE severity and promote functional recovery. In brief, this study provides not only a comprehensive characterization of the humoral response in EAE models, but also a proof of concept for a novel therapy to antagonize pathogenic anti-MOG antibodies.

Blood neutrophils, oligoclonal bands and bridging corticosteroids as predictive factors for MOGAD course: Insights from a multicentric Portuguese cohort

BACKGROUND

Myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD) is a heterogeneous entity with either a monophasic or relapsing course. Well-established predictors of relapsing disease are lacking.

OBJECTIVE

Identifying predictors of relapsing MOGAD, particularly at disease onset.

METHODS

A multicentre observational retrospective study was conducted to characterise a cohort of Portuguese adult MOGAD patients. Patients were identified from participating centre databases. Clinical and demographic data were collected from medical records. Bivariate analysis was conducted to compare patients with relapsing and monophasic MOGAD. Significant variables were included in a stepwise multiple regression analysis to identify independent predictors of relapse.

RESULTS

Eighty-seven MOGAD patients from 8 public hospitals were included. Relapsing MOGAD was found in 35.6% (n = 31). Mean diagnostic delay was 3.2 (±6.2) years and time to relapse was 4.4 (±6.4) years. Multiple logistic regression showed that higher neutrophil count (p < 0.01), presence of oligoclonal bands (p = 0.025) and no bridging corticosteroids (p = 0.038) at first attack were predictive of relapsing MOGAD.

CONCLUSION

Neutrophil count and oligoclonal bands at first attack may facilitate early decision-making regarding maintenance immunotherapy. Bridging corticosteroids may also influence the course of MOGAD. Further studies with prospective design are warranted.

The real-world applicability of the 2023 international myelin oligodendrocyte glycoprotein antibody-associated disease criteria in a Latin American cohort

BACKGROUND AND PURPOSE

The diagnostic criteria for myelin oligodendrocyte glycoprotein antibody (MOG-IgG)-associated disease (MOGAD) were published in 2023. We aimed to determine the performance of the new criteria in Latin American (LATAM) patients compared with the 2018 criteria and explore the significance of MOG-IgG titers in diagnosis.

METHODS

We retrospectively reviewed the medical records of LATAM (Argentina, Chile, Brazil, Peru, Ecuador, and Colombia) adult patients with one clinical MOGAD event and MOG-IgG positivity confirmed by cell-based assay. Both 2018 and 2023 MOGAD criteria were applied, calculating diagnostic performance indicators.

RESULTS

Among 171 patients (predominantly females, mean age at first attack = 34.1 years, mean disease duration = 4.5 years), 98.2% patients met the 2018 criteria, and of those who did not fulfill diagnostic criteria (n = 3), all tested positive for MOG-IgG (one low-positive and two without reported titer). Additionally, 144 (84.2%) patients met the 2023 criteria, of whom 57 (39.5%) had MOG-IgG+ titer information (19 clearly positive and 38 low-positive), whereas 87 (60.5%) patients had no MOG-IgG titer. All 144 patients met diagnostic supporting criteria. The remaining 27 patients did not meet the 2023 MOGAD criteria due to low MOG-IgG (n = 12) or lack of titer antibody access (n = 15), associated with the absence of supporting criteria. The 2023 MOGAD criteria showed a sensitivity of 86% (95% confidence interval = 0.80-0.91) and specificity of 100% compared to the 2018 criteria.

CONCLUSIONS

These findings support the diagnostic utility of the 2023 MOGAD criteria in an LATAM cohort in real-world practice, despite limited access to MOG-IgG titration.

Pediatric MOG-Ab-Associated Encephalitis: Supporting Early Recognition and Treatment

BACKGROUND AND OBJECTIVES

Antibodies to myelin oligodendrocyte glycoprotein (MOG-Ab) have recently been reported in patients with encephalitis who do not fulfill criteria for acute disseminated encephalomyelitis (ADEM). We evaluated a cohort of these children and compared them with children with ADEM.

METHODS

This retrospective, multicenter cohort study comprised consecutive patients <18 years of age with MOG-Ab who fulfilled criteria for autoimmune encephalitis. These patients were stratified into (1) children not fulfilling criteria for ADEM (encephalitis phenotype) and (2) children with ADEM. Clinical/paraclinical data were extracted from the electronic records. Comparisons were made using the Mann-Whitney U test and χ2 Fisher exact test for statistical analysis.

RESULTS

From 235 patients with positive MOG-Ab, we identified 33 (14%) with encephalitis and 74 (31%) with ADEM. The most common presenting symptoms in children with encephalitis were headache (88%), seizures (73%), and fever (67%). Infective meningoencephalitis was the initial diagnosis in 67%. CSF pleocytosis was seen in 79%. Initial MRI brain was normal in 8/33 (24%) patients. When abnormal, multifocal cortical changes were seen in 66% and unilateral cortical changes in 18%. Restricted diffusion was demonstrated in 43%. Intra-attack new lesions were seen in 7/13 (54%). When comparing with children with ADEM, children with encephalitis were older (median 8.9 vs 5.7 years, p = 0.005), were more likely to be admitted to intensive care (14/34 vs 4/74, p < 0.0001), were given steroid later (median 16.6 vs 9.6 days, p = 0.04), and were more likely to be diagnosed with epilepsy at last follow-up (6/33 vs 1/74, p = 0.003).

DISCUSSION

MOG-Ab should be tested in all patients with suspected encephalitis even in the context of initially normal brain MRI. Although exclusion of infections should be part of the diagnostic process of any child with encephalitis, in immunocompetent children, when herpes simplex virus CSF PCR and gram stains are negative, these features do not preclude the diagnosis of immune mediated disease and should not delay initiation of first-line immunosuppression (steroids, IVIG, plasma exchange), even while awaiting the antibody results.

Extensive brainstem lesions in myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD): A case report

Myelin oligodendrocyte glycoprotein antibody-associated disease is a group of central nervous system demyelinating disorders caused by autoantibodies. While myelin oligodendrocyte glycoprotein antibody-associated disease typically presents as optic neuritis and myelitis in adults, this case report details a patient with brainstem lesions. A 45-year-old male presented with episodes of vertigo, nystagmus, and diplopia in left lateral gaze, which had persisted for 2 months, accompanied by headache. Computed tomography showed hyperdensity extending from the left side of the pons to the middle cerebellar peduncle. Magnetic resonance imaging revealed lesions exhibiting heterogeneous diffusion restriction, with enhancement that included granular and linear patterns. 18F-fluorodeoxyglucose positron emission tomography demonstrated increased uptake in these lesions. Following further evaluation, myelin oligodendrocyte glycoprotein antibody-associated disease was diagnosed. Treatment with high-dose corticosteroids initially alleviated symptoms, but symptoms flared upon reduction of the steroids. This case underscores the importance of considering myelin oligodendrocyte glycoprotein antibody-associated disease in the differential diagnosis of brainstem lesions and discusses distinguishing imaging features from similar conditions.

Clinical, prognostic and pathophysiological implications of MOG-IgG detection in the CSF: the importance of intrathecal MOG-IgG synthesis

BACKGROUND

Cerebrospinal fluid myelin oligodendrocyte glycoprotein IgG (CSF MOG-IgG) are found in a proportion of patients with MOG antibody-associated disorder (MOGAD) and have been associated with severe disease presentations. However, most studies did not systematically investigate the role of MOG-IgG intrathecal synthesis (ITS).

METHODS

We retrospectively studied 960 consecutive patients with paired serum and CSF samples screened for MOG-IgG using a live cell-based assays. MOG-IgG-specific antibody index (AIMOG) was systematically calculated using serum and CSF titres to assess MOG-IgG ITS, and clinical features were compared between MOG-IgG CSF+/CSF- and ITS+/ITS- patients.

RESULTS

MOG-IgG were found in 55/960 patients (5.7%; serum+/CSF-: 58.2%, serum+/CSF+: 34.5%; serum-/CSF+: 7.3%). Serum/CSF MOG-IgG titres showed a moderate correlation in patients without ITS (ρ=0.47 (CI 0.18 to 0.68), p<0.001), but not in those with ITS (ρ=0.14 (CI -0.46 to -0.65), p=0.65). There were no clinical-paraclinical differences between MOG-IgG CSF+ vs CSF- patients. Conversely, patients with MOG-IgG ITS showed pyramidal symptoms (73% vs 32%, p=0.03), spinal cord involvement (82% vs 39%, p=0.02) and severe outcome at follow-up (36% vs 5%, p=0.02) more frequently than those without MOG-IgG ITS. A multivariate logistic regression model indicated that MOG-IgG ITS was an independent predictor of a poor outcome (OR: 14.93 (CI 1.40 to 19.1); p=0.03). AIMOG correlated with Expanded Disability Status Scale (EDSS) scores at disease nadir and at last follow-up (p=0.02 and p=0.01).

CONCLUSIONS

Consistently with physiopathology, MOG-IgG ITS is a promising prognostic factor in MOGAD, and its calculation could enhance the clinical relevance of CSF MOG-IgG testing, making a case for its introduction in clinical practice.

Brain-targeted autoimmunity is strongly associated with Long COVID and its chronic fatigue syndrome as well as its affective symptoms

INTRODUCTION

Autoimmune responses contribute to the pathophysiology of Long COVID, affective symptoms and myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS).

OBJECTIVES

To examine whether Long COVID, and its accompanying affective symptoms and CFS are associated with immunoglobulin (Ig)A/IgM/IgG directed at neuronal proteins including myelin basic protein (MBP), myelin oligodendrocyte glycoprotein (MOG), synapsin, α + β-tubulin, neurofilament protein (NFP), cerebellar protein-2 (CP2), and the blood-brain-barrier-brain-damage (BBD) proteins claudin-5 and S100B.

METHODS

IgA/IgM/IgG to the above neuronal proteins, human herpes virus-6 (HHV-6) and Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) were measured in 90 Long COVID patients and 90 healthy controls, while C-reactive protein (CRP), and advanced oxidation protein products (AOPP) in association with affective and CFS ratings were additionally assessed in a subgroup thereof.

RESULTS

Long COVID is associated with significant increases in IgG directed at tubulin (IgG-tubulin), MBP, MOG and synapsin; IgM-MBP, MOG, CP2, synapsin and BBD; and IgA-CP2 and synapsin. IgM-SARS-CoV-2 and IgM-HHV-6 antibody titers were significantly correlated with IgA/IgG/IgM-tubulin and -CP2, IgG/IgM-BBD, IgM-MOG, IgA/IgM-NFP, and IgG/IgM-synapsin. Binary logistic regression analysis shows that IgM-MBP and IgG-MBP are the best predictors of Long COVID. Multiple regression analysis shows that IgG-MOG, CRP and AOPP explain together 41.7 % of the variance in the severity of CFS. Neural network analysis shows that IgM-synapsin, IgA-MBP, IgG-MOG, IgA-synapsin, IgA-CP2, IgG-MBP and CRP are the most important predictors of affective symptoms due to Long COVID with a predictive accuracy of r = 0.801.

CONCLUSION

Brain-targeted autoimmunity contributes significantly to the pathogenesis of Long COVID and the severity of its physio-affective phenome.

The Varying Faces of MOGAD: A Case Series

ABSTRACT

Myelin oligodendrocyte glycoprotein-immunoglobulin G (MOG-IgG)-associated disease (MOGAD) is an immune mediated demyelinating disorder initially described as a subtype of neuromyelitis optica spectrum disorder with antibodies against MOG. Recently, it has been described as a separate disease entity with unique clinical and radiological features. We herein report the clinical details of eight MOG-IgG-positive patients to highlight the peculiar and varied clinical and radiological features of this condition. Encephalitis was the most common presenting feature in our study, especially in pediatric cases. Tremors and parkinsonism were noted in four cases, of which one was a child. Monophasic course was noted in seven patients. Relapsing course was noted only in a single patient who was initiated on immunosuppressants. The clinical pictures highlight the importance of screening for anti-MOG in individuals with encephalitic and multiaxial symptoms in spite of having normal imaging. Acute demyelinating encephalomyelitis such as imaging features in the pediatric age group may also be a consideration for MOG testing.

Case report: Infectious mononucleosis with bilateral retinal haemorrhages under myelin oligodendrocyte glycoprotein antibody-associated disease

Background

Bilateral optic neuritis associated with optic disc swelling is a common feature of myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD). However, extensive deep retinal haemorrhages have not been described in the context of MOG-associated optic neuritis. Here, we report a case of infectious mononucleosis with marked binocular peripapillary and perivascular haemorrhages as well as extensive deep retinal haemorrhages in the presence of MOGAD.

Case report

A 39-year-old Chinese woman presenting with subacute binocular vision reduction with no light perception was diagnosed with MOGAD. Fundus examination revealed the presence of binocular peripapillary and perivascular haemorrhages as well as extensive deep retinal haemorrhages with severe optic disc swelling greater in the right eye than in the left and dilated and tortuous retinal venules. The patient tested positive for the Epstein-Barr virus (EBV) antigen (595 U/mL) and the EBV capsid antigen (>750 U/mL). She had a fever and right upper quadrant abdominal pain, and a doctor determined splenomegaly 1 week before the onset of orbital pain and decreased vision acuity. Medical history and laboratory tests indicated the presence of concurrent infectious mononucleosis. Other investigational indicators of retinal haemorrhages, including hypertension, diabetes mellitus, vascular disease, systemic lupus erythematosus, metabolic disease, and renal or liver dysfunction, were absent.

Discussion

This case suggests that retinal haemorrhage is a possible complication of infectious mononucleosis in the presence of MOGAD.

Apheresis therapies in MOGAD: a retrospective study of 117 therapeutic interventions in 571 attacks

BACKGROUND

Incomplete attack remission is the main cause of disability in myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD). Apheresis therapies such as plasma exchange and immunoadsorption are widely used in neuroimmunology. Data on apheresis outcomes in MOGAD attacks remain limited.

METHODS

We retrospectively evaluated all apheresis treated attacks occurring in patients with MOGAD between 2008 and 2023 at 18 Neuromyelitis Optica Study Group centres. Treatment response was categorised as complete, partial or no remission. Preattack and follow-up Expanded Disability Status Scale (EDSS) and visual Functional System Scores (FSS) were used to calculate absolute outcomes (ΔEDSS/Δvisual FSS). Predictors of complete remission were analysed using a generalised linear mixed model.

RESULTS

Apheresis was used for 117/571 (20.5%) attacks in 85/209 (40.7%) patients. Attacks with simultaneous optic neuritis and myelitis were treated more often with apheresis (42.4%, n=14) than isolated myelitis (25.2%, n=35), cerebral manifestation (21.0%, n=17) or isolated optic neuritis (17.6%, n=51). Apheresis was initiated as first-line therapy in 12% (4.5 (IQR 0-11) days after attack onset), second-line therapy in 62% (15 (IQR 6.75-31) days) and third-line therapy in 26% (30 (IQR 19-42) days). Complete remission was achieved in 21%, partial remission in 70% and no remission in 9% of patients. First-line apheresis (OR 2.5, p=0.040) and concomitant disease-modifying therapy (OR 1.5, p=0.011) were associated with complete remission. Both parameters were also associated with a favourable ΔEDSS. No differences in outcomes were observed between the apheresis types.

CONCLUSION

Apheresis is frequently used in MOGAD attacks. An early start as first-line therapy and concomitant disease-modifying therapy predict full attack recovery.

Distinct virtual histology of grey matter atrophy in four neuroinflammatory diseases

Grey matter (GM) atrophies are observed in multiple sclerosis, neuromyelitis optica spectrum disorders [NMOSD; both anti-aquaporin-4 antibody-positive (AQP4+) and -negative (AQP4-) subtypes] and myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD). Revealing the pathogenesis of brain atrophy in these disorders would help their differential diagnosis and guide therapeutic strategies. To determine the neurobiological underpinnings of GM atrophies in multiple sclerosis, AQP4+ NMOSD, AQP4- NMOSD and MOGAD, we conducted a virtual histology analysis that links T1-weighted image derived GM atrophy and gene expression using a multicentre cohort of 324 patients with multiple sclerosis, 197 patients with AQP4+ NMOSD, 75 patients with AQP4- NMOSD, 47 patients with MOGAD and 2169 healthy control subjects. First, interregional GM atrophy profiles across the cortical and subcortical regions were determined using Cohen's d between patients with multiple sclerosis, AQP4+ NMOSD, AQP4- NMOSD or MOGAD and healthy controls. The GM atrophy profiles were then spatially correlated with the gene expression levels extracted from the Allen Human Brain Atlas, respectively. Finally, we explored the virtual histology of clinical-feature relevant GM atrophy using a subgroup analysis that stratified by physical disability, disease duration, number of relapses, lesion burden and cognitive function. Multiple sclerosis showed a severe widespread GM atrophy pattern, mainly involving subcortical nuclei and brainstem. AQP4+ NMOSD showed an obvious widespread pattern of GM atrophy, predominately located in occipital cortex as well as cerebellum. AQP4- NMOSD showed a mild widespread GM atrophy pattern, mainly located in frontal and parietal cortices. MOGAD showed GM atrophy mainly involving the frontal and temporal cortices. High expression of genes specific to microglia, astrocytes, oligodendrocytes and endothelial cells in multiple sclerosis, S1 pyramidal cells in AQP4+ NMOSD, as well as S1 and CA1 pyramidal cells in MOGAD, had spatial correlations with GM atrophy profile, while no atrophy profile-related gene expression was found in AQP4- NMOSD. Virtual histology of clinical feature-relevant GM atrophy pointed mainly to the shared neuronal and endothelial cells, among the four neuroinflammatory diseases. The unique underlying virtual histology patterns were microglia, astrocytes and oligodendrocytes for multiple sclerosis; astrocytes for AQP4+ NMOSD; and oligodendrocytes for MOGAD. Neuronal and endothelial cells were shared potential targets across these neuroinflammatory diseases. These findings may help the differential diagnoses of these diseases and promote the use of optimal therapeutic strategies.