Myelin oligodendrocyte glycoprotein antibodies in neurological disease

Biomarkers for neuromyelitis optica: a visual analysis of emerging research trends

Neuromyelitis optica is an inflammatory demyelinating disease of the central nervous system that differs from multiple sclerosis. Over the past 20 years, the search for biomarkers for neuromyelitis optica has been ongoing. Here, we used a bibliometric approach to analyze the main research focus in the field of biomarkers for neuromyelitis optica. Research in this area is consistently increasing, with China and the United States leading the way on the number of studies conducted. The Mayo Clinic is a highly reputable institution in the United States, and was identified as the most authoritative institution in this field. Furthermore, Professor Wingerchuk from the Mayo Clinic was the most authoritative expert in this field. Keyword analysis revealed that the terms "neuromyelitis optica" (261 times), "multiple sclerosis" (220 times), "neuromyelitis optica spectrum disorder" (132 times), "aquaporin 4" (99 times), and "optical neuritis" (87 times) were the most frequently used keywords in literature related to this field. Comprehensive analysis of the classical literature showed that the majority of publications provide conclusive research evidence supporting the use of aquaporin-4-IgG and neuromyelitis optica-IgG to effectively diagnose and differentiate neuromyelitis optica from multiple sclerosis. Furthermore, aquaporin-4-IgG has emerged as a highly specific diagnostic biomarker for neuromyelitis optica spectrum disorder. Myelin oligodendrocyte glycoprotein-IgG is a diagnostic biomarker for myelin oligodendrocyte glycoprotein antibody-associated disease. Recent biomarkers for neuromyelitis optica include cerebrospinal fluid immunological biomarkers such as glial fibrillary acidic protein, serum astrocyte damage biomarkers like FAM19A5, serum albumin, and gamma-aminobutyric acid. The latest prospective clinical trials are exploring the potential of these biomarkers. Preliminary results indicate that glial fibrillary acidic protein is emerging as a promising candidate biomarker for neuromyelitis optica spectrum disorder. The ultimate goal of future research is to identify non-invasive biomarkers with high sensitivity, specificity, and safety for the accurate diagnosis of neuromyelitis optica.

Joint radiomics and spatial distribution model for MRI-based discrimination of multiple sclerosis, neuromyelitis optica spectrum disorder, and myelin-oligodendrocyte-glycoprotein-IgG-associated disorder

OBJECTIVE

To develop a discrimination pipeline concerning both radiomics and spatial distribution features of brain lesions for discrimination of multiple sclerosis (MS), aquaporin-4-IgG-seropositive neuromyelitis optica spectrum disorder (NMOSD), and myelin-oligodendrocyte-glycoprotein-IgG-associated disorder (MOGAD).

METHODS

Hyperintensity T2 lesions were delineated in 212 brain MRI scans of MS (n = 63), NMOSD (n = 87), and MOGAD (n = 45) patients. To avoid the effect of fixed training/test dataset sampling when developing machine learning models, patients were allocated into 4 sub-groups for cross-validation. For each scan, 351 radiomics and 27 spatial distribution features were extracted. Three models, i.e., multi-lesion radiomics, spatial distribution, and joint models, were constructed using random forest and logistic regression algorithms for differentiating: MS from the others (MS models) and MOGAD from NMOSD (MOG-NMO models), respectively. Then, the joint models were combined with demographic characteristics (i.e., age and sex) to create MS and MOG-NMO discriminators, respectively, based on which a three-disease discrimination pipeline was generated and compared with radiologists.

RESULTS

For classification of both MS-others and MOG-NMO, the joint models performed better than radiomics or spatial distribution model solely. The MS discriminator achieved AUC = 0.909 ± 0.027 and bias-corrected C-index = 0.909 ± 0.027, and the MOG-NMO discriminator achieved AUC = 0.880 ± 0.064 and bias-corrected C-index = 0.883 ± 0.068. The three-disease discrimination pipeline differentiated MS, NMOSD, and MOGAD patients with 75.0% accuracy, prominently outperforming the three radiologists (47.6%, 56.6%, and 66.0%).

CONCLUSIONS

The proposed pipeline integrating multi-lesion radiomics and spatial distribution features could effectively differentiate MS, NMOSD, and MOGAD.

CLINICAL RELEVANCE STATEMENT

The discrimination pipeline merging both radiomics and spatial distribution features of brain lesions may facilitate the differential diagnoses of multiple sclerosis, neuromyelitis optica spectrum disorder, and myelin-oligodendrocyte-glycoprotein-IgG-associated disorder.

KEY POINTS

• Our study introduces an approach by combining radiomics and spatial distribution models. • The joint model exhibited superior performance in distinguishing multiple sclerosis from aquaporin-4-IgG-seropositive neuromyelitis optica spectrum disorder and myelin-oligodendrocyte-glycoprotein-IgG-associated disorder as well as discriminating the latter two diseases. • The three-disease discrimination pipeline showcased remarkable accuracy, surpassing the performance of experienced radiologists, highlighting its potential as a valuable diagnostic tool.

Alterations of brain structural and functional connectivity networks topology and decoupling in pediatric myelin oligodendrocyte glycoprotein antibody-associated disease

OBJECTIVE

To investigate the alteration in structural and functional connectivity networks (SCN and FCN) as well as their coupling in pediatric myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD), and determine if these properties could serve as potential biomarkers for the disease.

MATERIALS AND METHODS

In total of 32 children with MOGAD and 30 age- and sex-matched healthy controls (HC) were employed to construct the SCN and FCN, respectively. The graph-theoretical analyses of the global properties, node properties of the 90 brain nodes, and the structural-functional connectivity (SC-FC) coupling of the two networks were performed. The graph-theoretical properties that exhibited significant differences were analyzed using partial correlation analysis in conjunction with the clinical scales, including the expanded disability status scale (EDSS), modified Rankin scale (mRS), and pediatric cerebral performance category (PCPC) of the MOGAD group. Subsequently, a machine learning model was developed to discriminate between MOGAD and the HC group, aiming to explore the potential of these properties as biomarkers.

RESULTS

The SCN of the MOGAD group exhibited aberrant global properties, including an increased characteristic path length (Lp) and a decreased global efficiency (Eg), along with reduced nodal properties such as degree centrality (Dc), nodal efficiency (Ne), and local efficiency in multiple nodes. The FCN of the MOGAD group only exhibited decreased Dc, Ne, and betweenness centrality in two nodes of nodal properties. Besides, MOGAD showed a significant decrease in SC-FC coupling compared to the HC group. The analysis of partial correlation revealed significant correlations between several properties and the scales of EDSS and mRS in the MOGAD group. The machine learning method was used to extract six features and establish the model, achieving a classification accuracy of 82.3% for MOGAD.

CONCLUSIONS

Pediatric MOGAD showed a more pronounced impairment in the SCN along with decoupling of SC-FC. Both partial correlation analysis and discriminant modeling suggest that alterations in brain network properties have the potential as biomarkers for assessing brain damage in MOGAD.

Prevalence of anti-myelin oligodendrocyte glycoprotein antibodies across neuroinflammatory and neurodegenerative diseases

Inflammatory central nervous system (CNS) diseases, such as multiple sclerosis (MS) and myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD), are characterized by humoral immune abnormalities. Anti-MOG antibodies are not specific to MOGAD, with their presence described in MS. Autoantibodies may also be present and play a role in various neurodegenerative diseases. Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease driven by motor neuron dysfunction. While immune involvement in ALS has been recognized, the presence of antibodies targeting CNS myelin antigens has not been established. We aimed to establish a live cell-based assay for quantification of serum anti-MOG IgG1 in patients with CNS diseases, including MS and ALS. In total, 771 serum samples from the John L. Trotter MS Center and the Northeast ALS Consortium were examined using a live cell-based assay for detection of anti-MOG IgG1. Samples from three cohorts were tested in blinded fashion: healthy control (HC) subjects, patients with clinically diagnosed MOGAD, and an experimental group of ALS and MS patients. All samples from established MOGAD cases were positive for anti-MOG antibodies, while all HC samples were negative. Anti-MOG IgG1 was detected in 65 of 658 samples (9.9%) from MS subjects and 4 of 108 (3.7%) samples from ALS subjects. The presence of serum anti-MOG IgG1 in MS and ALS patients raises questions about the contribution of these antibodies to disease pathophysiology as well as accuracy of diagnostic approaches for CNS inflammatory diseases.

Clinical characteristics of patients with myelin oligodendrocyte glycoprotein antibodies

PURPOSE OF REVIEW

The clinical landscape associated to myelin oligodendrocyte glycoprotein antibodies (MOG-Ab) has undergone a remarkable transformation over the past two decades, primarily driven by advancements in antibody detection techniques that have enhanced both the specificity and sensitivity of assays, enabling the identification of novel clinical phenotypes.

RECENT FINDINGS

Recent pivotal research publications, comprehensive reviews from established research groups, and most notably the first proposed international criteria for MOG-Ab associated disease (MOGAD) have substantially enriched our understanding of the clinical features associated with MOG-Ab. This review presents a comprehensive overview of the clinical characteristics of patients with MOG-Ab, systematically examining each core clinical syndrome defined by the proposed international MOGAD criteria. We incorporated recent insights and discussed potential challenges in applying these criteria across diverse clinical scenarios.

SUMMARY

The proposed international MOGAD criteria provide a comprehensive, homogeneous, and specific framework for characterizing the clinical features of patients with MOG-Ab, encompassing both paediatric and adult populations. In the future, the widespread adoption of specific and reliable assays for MOG-Ab detection, complemented by the development of surrogate fluid and imaging markers, holds promise for better characterizing atypical presentations, only-cerebrospinal fluid positivity and the MOGAD "seronegative" situations.

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.

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.

Isolated Optic Neuritis: Etiology, Characteristics, and Outcomes in a US Mountain West Cohort

BACKGROUND

The diagnosis and treatment of autoimmune optic neuritis (ON) has improved with the accessibility and reliability of aquaporin-4 (AQP4) and myelin oligodendrocyte glycoprotein (MOG) antibody testing, yet autoantibody-negative ON remains common. This study describes the demographic, clinical, and outcome data in patients with isolated ON across the pediatric and adult cohort.

METHODS

A retrospective chart review of University of Utah Health patients with the International Classification of Diseases (ICD) code of ICD-9 377.30 (ON unspecified), ICD-9 377.39 (other ON), or ICD-10 H46 (ON) and at least 2 ophthalmologic evaluations were conducted between February 2011 and July 2023. Only isolated cases of ON without other brain or spinal demyelinating lesions were evaluated. Differences in demographic and clinical characteristics between AQP4, MOG, and Other-ON were determined.

RESULTS

Of the 98 patients (15 children and 83 adults), 9 (9.2%) were positive for AQP4-IgG and 35 (35.7%) tested positive for MOG-IgG. Fifty-four were classified into Other-ON, of which 7 (13.0%) had recurrence or new demyelinating lesions during a median follow-up of 12.5 months-2 were ultimately diagnosed with recurrent isolated ON (RION), 1 with chronic relapsing inflammatory ON (CRION), 2 with multiple sclerosis, 1 with collapsin response-mediator protein (CRMP)-5-ON, and 1 with seronegative neuromyelitis optica spectrum disorder. Four patients were treated with long-term immunosuppressive therapy. No patients with RION or CRION had preceding infections; they had first recurrences of ON within 2 months. At presentation, AQP4-ON (75%) and MOG-ON (48.8%) had more severe vision loss (visual acuity <20/200) than Other-ON (23.2%, P = 0.01). At the 1-month follow-up, 93.0% of patients with MOG-ON and 89.3% of patients with Other-ON demonstrated a visual acuity ≥20/40, compared with only 50% of patients with AQP4-ON (P < 0.01). By the last follow-up, 37.5% of the AQP4-ON still exhibited visual acuity <20/40, including 25% who experienced severe vision loss (visual acuity <20/200). By contrast, over 95% of patients with MOG-ON and Other-ON maintained a visual acuity of ≥20/40. In our cohort, over a quarter of pediatric cases presented with simultaneous bilateral ON, 40% had a preceding infection, and 44.4% initially presented with a visual acuity <20/200. Two pediatric cases had recurrence, and both were MOG-ON. By their last follow-up, all pediatric cases had achieved a visual acuity of 20/40 or better. In addition, pediatric cases were more likely to exhibit disc edema compared with adult cases (100% vs 64%, P < 0.01).

CONCLUSIONS

Despite recent advances in identification and availability of testing for AQP4-IgG and MOG-IgG, over half of patients who presented with isolated ON remained with an "idiopathic" diagnostic label. As more than 1 in 10 patients with AQP4-IgG and MOG-IgG negative ON experienced recurrence or develop new demyelinating lesions, clinicians should provide anticipatory guidance and closely monitor for potential long-term outcomes. In addition, it is crucial to re-evaluate the diagnosis in cases of poor recovery, ON recurrence, and the emergence of new neurological symptoms, as ON can often be the initial presentation of other conditions.

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.

Leptomeningeal Enhancement in Pediatric Anti-Myelin Oligodendrocyte Glycoprotein Antibody Disease, Multiple Sclerosis, and Neuromyelitis Optica Spectrum Disorder

BACKGROUND

Anti-myelin oligodendrocyte glycoprotein (MOG) antibody disease (MOGAD) is a type of acquired demyelinating disease that is distinct from multiple sclerosis (MS) and aquaporin-4 antibody neuromyelitis optica spectrum disorder (AQP4-NMOSD). Leptomeningeal enhancement (LME) has been reported in children and adults with MOGAD, and in adults with MS and AQP4-NMOSD, but less is known about LME in pediatric-onset MS (POMS) and pediatric AQP4-NMOSD. Here we compare the rates of LME in children with MOGAD, POMS, and AQP4-NMOSD.

METHODS

A retrospective chart review was performed in patients with MOGAD, POMS, and AQP4-NMOSD who presented to our institution. Clinical characteristics, imaging features, and relapsing data were included. Descriptive statistics were used, including chi-square or Fischer exact test, to compare proportions. The Benjamini-Hochberg procedure was used to correct for multiple comparisons.

RESULTS

A total of 42 children were included: 16 with POMS, six with AQP4-NMOSD, and 20 with MOGAD. Brain LME was only observed in the MOGAD group (six of 20 = 30%) when compared with zero (0%) POMS and AQP4-NMOSD (P = 0.012). Relapsing disease occurred in nine of 20 (45%), but LME did not associate with relapse.

CONCLUSIONS

LME is only observed in pediatric MOGAD and not in POMS or pediatric AQP4-NMOSD. LME did not predict relapses in MOGAD. Further work is needed to determine the clinical significance of LME in pediatric MOGAD.

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.

Aberrant white matter microstructure detected by automatic fiber quantification in pediatric myelin oligodendrocyte glycoprotein antibody-associated disease

BACKGROUND AND OBJECTIVES

Myelin oligodendrocyte glycoprotein antibody-associated diseases (MOGAD) is an idiopathic inflammatory demyelinating disorder in children, for which the precise damage patterns of the white matter (WM) fibers remain unclear. Herein, we utilized diffusion tensor imaging (DTI)-based automated fiber quantification (AFQ) to identify patterns of fiber damage and to investigate the clinical significance of MOGAD-affected fiber tracts.

METHODS

A total of 28 children with MOGAD and 31 healthy controls were included in this study. The AFQ approach was employed to track WM fiber with 100 equidistant nodes defined along each tract for statistical analysis of DTI metrics in both the entire and nodal manner. The feature selection method was used to further screen significantly aberrant DTI metrics of the affected fiber tracts or segments for eight common machine learning (ML) to evaluate their potential in identifying MOGAD. These metrics were then correlated with clinical scales to assess their potential as imaging biomarkers.

RESULTS

In the entire manner, significantly reduced fractional anisotropy (FA) was shown in the left anterior thalamic radiation, arcuate fasciculus, and the posterior and anterior forceps of corpus callosum in MOGAD (all p < 0.05). In the nodal manner, significant DTI metrics alterations were widely observed across 37 segments in 10 fiber tracts (all p < 0.05), mainly characterized by decreased FA and increased radial diffusivity (RD). Among them, 14 DTI metrics in seven fiber tracts were selected as important features to establish ML models, and satisfactory discrimination of MOGAD was obtained in all models (all AUC > 0.85), with the best performance in the logistic regression model (AUC = 0.952). For those features, the FA of left cingulum cingulate and the RD of right inferior frontal-occipital fasciculus were negatively and positively correlated with the expanded disability status scale (r = -0.54, p = 0.014; r = 0.43, p = 0.03), respectively.

CONCLUSION

Pediatric MOGAD exhibits extensive WM fiber tract aberration detected by AFQ. Certain fiber tracts exhibit specific patterns of DTI metrics that hold promising potential as biomarkers.

Clinical features of adult patients with positive NMDAR-IgG coexisting with MOG-IgG

INTRODUCTION

This study was designed to analyze clinical and radiographic features of adult patients coexisting with NMDAR-IgG and MOG-IgG.

METHODS

Eleven adult patients coexisting with NMDAR-IgG and MOG-IgG were collected from Xiangya Hospital, Central South University, between June 2017 and December 2021. Fifty-five patients with anti-NMDAR encephalitis and 49 with MOG-AD were served as controls.

RESULTS

Onset age was 27 (IQR 20-34) years old. Seizures and psychotic symptoms were prominent symptoms. Ten of eleven patients presented abnormal T2/FLAIR hyperintensity, mainly involving the cortex, brainstem, and optic nerve. Compared with the NMDAR IgG ( +)/MOG IgG ( -) group, the NMDAR IgG ( +)/MOG IgG ( +) group showed more ataxia symptoms (27.3% vs. 3.6%, P = 0.037), while more T2/FLAIR hyperintensity lesions were found in the brainstem (54.5% vs. 7.3%, P < 0.001) and optic nerve (27.3% vs. 1.8%, P = 0.011) with more abnormal MRI patterns (90.9% vs. 41.8%, P = 0.003). In comparison with the NMDAR IgG ( -)/MOG IgG ( +) group, the NMDAR IgG ( +)/MOG IgG ( +) group had more seizures (72.7% vs. 24.5%, P = 0.007) and mental symptoms (45.5% vs. 0, P < 0.001). The NMDAR IgG ( +)/MOG IgG ( +) group tended to be treated with corticosteroids alone (63.6% vs. 20.0%, P = 0.009), more prone to recur (36.5% vs. 7.3%, P = 0.028) and lower mRS score (P = 0.036) at the last follow-up than pure anti-NMDAR encephalitis.

CONCLUSION

The symptoms of the NMDAR IgG ( +)/MOG IgG ( +) group were more similar to anti-NMDAR encephalitis, while MRI patterns overlapped more with MOG-AD. Detecting both NMDAR-IgG and MOG-IgG maybe warranted in patients with atypical encephalitis symptoms and demyelinating lesions in infratentorial regions.

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.

Characteristics of cerebrospinal fluid oligoclonal band in anti-myelin oligodendrocyte glycoprotein (MOG) antibody associated disease

Objective

To analyze the immune parameters of cerebrospinal fluid (CSF) and oligoclonal band (OCB) type in patients with anti-myelin oligodendrocyte glycoprotein (MOG) antibody-associated diseases (MOGAD).

Methods

Patients who were seropositive for MOG-IgG and diagnosed with MOGAD according to the diagnosis criteria in the Department of Neurology, Huashan Hospital, Fudan University from December 2020 to June 2022 were retrospectively included in this study. Complete clinical data, blood and cerebrospinal fluid samples were collected from all the participants. Paired serum and CSF MOG-IgG and autoimmune encephalitis antibody were assayed by Cell Based Assay (CBA) based on transfected target antigens. Paired serum and CSF albumin and IgG were detected by turbidimetric scattering method, and OCB was detected by standard operation procedure as described.

Results

A total of 86 patients (44 males and 42 females) with MOGAD were included in this study, with a median age of 30 years (range: 5-82 years). Among all the patients, 73 patients showed OCB type I, 12 patients showed OCB type II, and one patient showed OCB type III. The overall positive rate of CSF-OCB in MOGAD patients was 15.1 %. The 24-h intrathecal synthesis rate of CSF in the OCB-positive group (n = 13) was higher than that in the OCB-negative group [n = 73, 0.62 (0.26) vs 5.11 (13.67), P = 0.003]. Subgroup analysis revealed that the positive rates of CSF-OCB in the single MOG group (n = 61) and the group combined with other antibodies (n = 25) were 14.8 % and 16.0 %, respectively. The incidence of meningoencephalitis (13/61 vs 13/25, P = 0.011) was significantly different between the two groups. The proportion of patients with high (≥1:32) or low (≤1:10) CSF MOG-IgG also showed significant difference in the group combined with other antibodies (P = 0.032). Optic neuritis was more common in the relapse course group (n = 49) than the monophasic course group (n = 37, P < 0.001) No significant diferences of CSF immune parameters were found in the MOG-IgGserum+/CSF- group and the MOG-IgGserum+/CSF + group, and the titer of MOG-IgG in the serum or CSF did not influence CSF immune parameters in different subgroups.

Conclusion

The overall positive rate of CSF-OCB in MOGAD patients was 15.1 %. The 24-h intrathecal synthesis rate of cerebrospinal fluid in the OCB-positive group was higher than that in the OCB-negative group. This study illustrated OCB characterization in MOGAD patients, and will shed light on the standardization of OCB test in the study of immune diseases.

Clinical features and prognosis of Tibetan patients with neuromyelitis optica spectrum disorder are different from those of Han Chinese patients

We compared the prognosis of Tibetan and Han Chinese patients with neuromyelitis optica spectrum disorder (NMOSD). The Expanded Disability Status Scale (EDSS) score at each attack, response to immunosuppressive therapy, risk of first relapse, severe attack, visual disability, motor disability, and total risk of disability were compared between Tibetan and Han Chinese patients. Tibetan patients showed higher EDSS during acute attacks. Annualized relapse rate did not differ between groups. Risk of severe attack, visual disability, and total risk of disability were higher in Tibetan patients. Tibetan patients with NMOSD have a higher risk of poor prognosis than Han Chinese patients.

Recent advances in nanopore-based analysis for carbohydrates and glycoconjugates

Saccharides are not only the basic constituents and nutrients of living organisms, but also participate in various life activities, and play important roles in cell recognition, immune regulation, development, cancer, etc. The analysis of carbohydrates and glycoconjugates is a necessary means to study their transformations and physiological roles in living organisms. Existing detection techniques can hardly meet the requirements for the analysis of carbohydrates and glycoconjugates in complex matrices as they are expensive, involve complex derivatization, and are time-consuming. Nanopore sensing technology, which is amplification-free and label-free, and is a high-throughput process, provides a new solution for the identification and sequencing of carbohydrates and glycoconjugates. This review highlights recent advances in novel nanopore-based single-molecule sensing technologies for the detection of carbohydrates and glycoconjugates and discusses the advantages and challenges of nanopore sensing technologies. Finally, current issues and future perspectives are discussed with the aim of improving the performance of nanopores in complex media diagnostic applications, as well as providing a new direction for the quantification of glycan chains and the study of glycan chain properties and functions.

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.

Risk of central nervous system demyelinating attack or optic neuritis recurrence after pediatric optic neuritis in Korea

PURPOSE

To investigate the rate of development of symptomatic central nervous system (CNS) demyelinating attacks or recurrent optic neuritis (ON) after the first episode of ON and its risk factors for Korean pediatric patients.

METHODS

This multicenter retrospective cohort study included the patients under 18 years of age (n=132) diagnosed with ON without previous or simultaneous CNS demyelinating diseases. We obtained the clinical data including the results of neuro-ophthalmological examinations, magnetic resonance images (MRIs), antibody assays, and laboratory tests. We investigated the chronological course of demyelinating disease with respect to the occurrence of neurological symptoms and/or signs, and calculated the 5-year cumulative probability of CNS demyelinating disease or ON recurrence.  RESULTS: During the follow-up period (63.1±46.7 months), 18 patients had experienced other CNS demyelinating attacks, and the 5-year cumulative probability was 14.0±3.6%. Involvement of the extraorbital optic nerve or optic chiasm and asymptomatic lesions on the brain or spinal MRI at initial presentation were significant predictors for CNS demyelinating attack after the first ON. The 5-year cumulative probability of CNS demyelinating attack was 44.4 ± 24.8% in the AQP4-IgG group, 26.2±11.4% in the MOG-IgG group, and 8.7±5.9% in the double-negative group (P=0.416). Thirty-two patients had experienced a recurrence of ON, and the 5-year cumulative probability was 24.6±4.0%. In the AQP4-IgG group, the 5-year cumulative probability was 83.3±15.2%, which was significantly higher than in the other groups (P<0.001).

CONCLUSIONS

A careful and multidisciplinary approach including brain/spinal imaging and antibody assay can help predict further demyelinating attacks in pediatric ON patients.

Proteomic profiling of cerebrospinal fluid in pediatric myelin oligodendrocyte glycoprotein antibody-associated disease

BACKGROUND

Myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD) is an autoimmune demyelinating disorder of the central nervous system.

METHODS

Extracted proteins from 34 cerebrospinal fluid (CSF) samples [patients with MOGAD (MOG group, n = 12); healthy controls (HC group, n = 12); patients with MOG seronegative and metagenomics next-generation sequencing-negative inflammatory neurological diseases (IND group, n = 10)] were processed and subjected to label-free quantitative proteomics. Supervised partial least squares-discriminant analysis (PLS-DA) and orthogonal PLS-DA (O-PLS-DA) models were also performed based on proteomics data. Functional analysis of differentially expressed proteins (DEPs) was performed using Gene Ontology, InterPro, and Kyoto Encyclopedia Genes and Genomes. An enzyme-linked immunosorbent assay was used to determine the complement levels in serum from patients with MOGAD.

RESULTS

Four hundred and twenty-nine DEPs (149 upregulated and 280 downregulated proteins) were identified in the MOG group compared to the HC group according to the P value and fold change (FC). Using the O-PLS-DA model, 872 differentially abundant proteins were identified with variable importance projection (VIP) scores > 1. Five proteins (gamma-glutamyl hydrolase, cathepsin F, interalpha-trypsin inhibitor heavy chain 5, latent transforming growth factor beta-binding protein 4 and leukocyte-associated immunoglobulin-like receptor 1) overlapping between the top 30 DEPs with top-ranked P value and FC and top 30 proteins in PLS-DA VIP lists were acquired. Functional analysis revealed that the dysregulated proteins in the MOG group were primarily involved in complement and coagulation cascades, cell adhesion, axon guidance, and glycosphingolipid biosynthesis compared to the HC group.

CONCLUSION

The proteomic alterations in CSF samples from children with MOGAD identified in the current study might provide opportunities for developing novel biomarker candidates.

Encephalitis is an Important Phenotype of Myelin Oligodendrocyte Glycoprotein Antibody-Associated Diseases: A Single-Center Cohort Study

BACKGROUND

Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is considered a demyelinating disease of the central nervous system, but an increasing number of encephalitis cases associated with MOG antibodies have been reported recently.

METHODS

This was a single-center, retrospective study. All data for pediatric patients with MOGAD diagnosed at Beijing Children's Hospital from January 2017 to January 2022 were collected. Clinical characteristics and outcomes were analyzed, and treatment responses were compared between the rituximab (RTX) and mycophenolate mofetil (MMF) groups.

RESULTS

A total of 190 patients (age range: 5 months to 16 years; median age: 7.2 years; females: 97) were included in this study. The phenotypes of the first attack included acquired demyelinating syndromes (105 [55%]), encephalitis other than acute disseminated encephalomyelitis (82 [43%]), and isolated meningitis (3 [2%]). After a median follow-up of 30.4 months (interquartile range: 14.8-43.7), 64 (34%) patients had relapses. Fifty-one of the 64 (80%) patients who had relapse received maintenance therapy, including MMF (41), RTX (11), maintenance intravenous immunoglobulin (two), and tocilizumab (two). The annualized relapse rates decreased significantly after treatment in both the RTX and MMF cohorts (P < 0.05); however, there were no significant differences between the two groups (P = 0.56). A total of 178 (94%) patients had complete (175 patients) or almost complete (three patients) recovery (modified Rankin scale [mRS] < 2), and 12 had moderate to severe deficits (mRS ≥ 2).

CONCLUSIONS

The spectrum of pediatric MOGAD is broader than previously reported and includes demyelinating syndromes and encephalitis. Encephalitis is an important initial phenotype observed in pediatric patients with MOGAD.

Clinical and Imaging Findings in Children with Myelin Oligodendrocyte Glycoprotein Antibody Associated Disease (MOGAD): From Presentation to Relapse

BACKGROUND AND PURPOSE

Myelin oligodendrocyte glycoprotein-antibody associated disease (MOGAD) is an increasingly recognized cause of demyelinating disease in children. The purpose of this study is to characterize the CNS imaging manifestations of pediatric MOGAD and identify clinical and imaging variables associated with relapse.

MATERIALS AND METHODS

We retrospectively identified children with serum antibody-positive MOGAD evaluated at our institution between 1997 and 2020. Clinical and demographic data were collected. MRIs of the brain, orbit, and spine at presentation and relapse were reviewed for location and pattern of abnormality.

RESULTS

Among 61 cases (34 girls), mean age at presentation was 7 years (IQR 4-11). At presentation, there was imaging involvement of the brain in 78.6% (44/56), optic pathway in 55.4% (31/56), and spine in 19.6% (11/56). Brain involvement was commonly in the frontal (70.5%, 31/44) and subcortical (75%, 33/44) white matter, with involvement of the thalamus and pons in 47.7% each (21/44). Optic neuritis (ON) was commonly bilateral (80.6%, 25/31) involving intraorbital segments (77.4%, 24/31). Spinal cord lesions were typically cervical (72.7%, 8/11) and multifocal (72.7%, 8/11).The imaging patterns were age-dependent; children ≤9 years more commonly demonstrated ADEM-like imaging pattern at presentation (39.4%, 13/33) and first relapse (8/23, 34.8%), while children >9 years more commonly had ON at presentation (34.8%, 8/23, P = .001) and FLAIR-hyperintense lesions in anti-MOG-associated encephalitis with seizures at first relapse (5/18, 27.8%, P = .008).

CONCLUSIONS

We describe the CNS imaging findings in pediatric MOGAD. The imaging pattern is age-dependent at presentation and first relapse. Younger age at presentation is associated with longer time to relapse.

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

Objective

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

Methods

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

Results

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

Conclusion

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

Potential clinical implications of molecular mimicry-induced autoimmunity

BACKGROUND

Molecular mimicry is hypothesized to be a mechanism by which autoimmune diseases are triggered. It refers to sequence or structural homology between foreign antigens and self-antigens, which can activate cross-reactive lymphocytes that attack host tissues. Elucidating the role of molecular mimicry in human autoimmunity could have important clinical implications.

OBJECTIVE

To review evidence for the role of molecular mimicry in major autoimmune diseases and discuss potential clinical implications.

METHODS

Comprehensive literature review of clinical trials, observational studies, animal models, and immunology studies on molecular mimicry in multiple sclerosis, type 1 diabetes, rheumatoid arthritis, lupus, Guillain-Barre syndrome, autoimmune myocarditis, and primary biliary cirrhosis published from 2000-2023.

RESULTS

Substantial indirect evidence supports molecular mimicry as a contributor to loss of self-tolerance in several autoimmune conditions. Proposed microbial triggers include Epstein-Barr virus, coxsackievirus, Campylobacter jejuni, and bacterial commensals. Key mechanisms involve cross-reactive T cells and autoantibodies induced by epitope homology between microbial and self-antigens. Perpetuation of autoimmunity involves epitope spreading, inflammatory mediators, and genetic factors.

CONCLUSIONS

Molecular mimicry plausibly explains initial stages of autoimmune pathogenesis induced by infection or microbiota disturbances. Understanding mimicry antigens and pathways could enable improved prediction, monitoring, and antigen-specific immunotherapy for autoimmune disorders. However, definitive proof of causation in humans remains limited. Further research should focus on establishing clinical evidence and utility.

Anti-aquaporin-4 immunoglobulin G/anti-myelin oligodendrocyte glycoprotein immunoglobulin G double-positive paraneoplastic neurological syndrome in a patient with triple-negative breast cancer

We report a rare case of paraneoplastic neurological syndrome with dual seropositivity of anti-aquaporin-4 and myelin oligodendrocyte glycoprotein antibodies in a 40 year-old woman with metastatic triple-negative breast cancer. She received multiple lines of anti-neoplastic treatment, including immunotherapy with pembrolizumab, as well as cytotoxic chemotherapy. Paraneoplastic meningoencephalomyelitis developed 2 years after diagnosis of breast cancer and 1 year after discontinuation of immunotherapy with pembrolizumab. She first developed longitudinally extending transverse myelitis followed by left optic neuritis and meningoencephalitis with new enhancing lesions in the brain and spinal leptomeninges. Cerebrospinal fluid analysis during both episodes showed normal glucose and protein, and elevated white blood cell count. Cytology was negative for malignancy. Cerebrospinal fluid was positive for neuromyelitis optica immunoglobulin G antibody anti-aquaporin-4, and autoimmune myelopathy panel was positive for myelin oligodendrocyte glycoprotein antibody. The patient had significant clinical and radiographic improvement after completion of five cycles of plasmapheresis followed by intravenous immunoglobulin. She did not have recurrence of paraneoplastic syndrome with maintenance rituximab every 6 months and daily low-dose prednisone. She succumbed to progressive systemic metastatic disease 4.5 years after her breast cancer diagnosis. This case shows that these antibodies can occur concurrently and cause clinical features, such as both neuromyelitis optica spectrum disorder and myelin oligodendrocyte glycoprotein antibody disease, in a patient with a singular type of cancer. We highlight the importance of testing for paraneoplastic etiology in cancer patients with radiographic menigoencephalomyelitis or meningitis with atypical symptoms of meningeal carcinomatosis and/or cerebrospinal fluid profile negative for leptomeningeal carcinomatosis.

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.

Myelin oligodendrocyte glycoprotein antibody and N-methyl-d-aspartate receptor antibody overlapping syndrome: insights from the recent case reports

The overlapping of two or more types of neural autoantibodies in one patient has increasingly been documented in recent years. The coexistence of myelin oligodendrocyte glycoprotein (MOG) and N-methyl-d-aspartate receptor (NMDAR) antibodies is most common, which leads to a unique condition known as the MOG antibody and NMDAR antibody overlapping syndrome (MNOS). Here, we have reviewed the pathogenesis, clinical manifestations, paraclinical features, and treatment of MNOS. Forty-nine patients with MNOS were included in this study. They were young males with a median onset age of 23 years. No tumors were observed in the patients, and 24 of them reported prodromal symptoms. The most common clinical presentations were psychiatric symptoms (35/49) and seizures (25/49). Abnormalities on magnetic resonance imaging involved the brainstem (11/49), cerebellum (9/49), and parietal lobe (9/49). Most patients mostly responded to immunotherapy and had a good long-term prognosis. However, the overall recurrence rate of MNOS was higher than that of mono antibody-positive diseases. The existence of concurrent NMDAR antibodies should be suspected in patients with MOG antibody-associated disease having psychiatric symptoms, seizures, movement disorders, or autonomic dysfunction. Similarly, serum MOG antibody testing should be performed when patients with anti-NMDAR encephalitis present with atypical clinical manifestations, such as visual impairment and limb weakness, and neuroradiological findings, such as optic nerve, spinal cord, or infratentorial involvement or meningeal enhancement. Early detection of the syndrome and prompt treatment can be beneficial for these patients, and maintenance immunosuppressive therapy is recommended due to the high overall recurrence rate of the syndrome.

Relapses and Serious Infections in Patients with Neuromyelitis Optica Spectrum Disorder Treated with Rituximab: A Swedish Single-Center Study

Neuromyelitis optica spectrum disorder (NMOSD) is a rare immune-mediated relapsing-remitting disease of the central nervous system. The usage of rituximab, as relapse-preventive therapy, in NMOSD is common. We performed a single-center retrospective cohort study to assess the risk of relapses and severe infectious events (SIEs) in rituximab-treated NMOSD patients. This study included 24 aquaporin-4 IgG+ (AQP4+), 8 myelin-oligodendrocyte-protein IgG+ (MOG+), and 10 double-seronegative NMOSD patients. Relapses were observed in 50% of all patients during a mean treatment time of 4.0 (range: 0.5-8.25) years. The incidence risk ratio (IRR) of relapse was three times higher in MOG+ compared to AQP4+ patients (IRR: 3.0, 95% confidence interval (CI); 1.2-7.7). SIEs occurred in 40% of all patients during follow-up. AQP4+ patients conferred an increased risk of SIEs compared to MOG+ patients (IRR; 5.3, 95% CI; 1.2-24.3). Incomplete CD19+ B-lymphocyte suppression was not correlated with relapse risk (hazard ratio; 1.9, 95% CI; 0.7-5.2), and there was no correlation between IgG-levels and SIE risk (odds ratio; 2.0, 95% CI; 0.8-4.8). In conclusion, considerable risks of both relapses and SIEs were observed in NMOSD patients exposed to rituximab, which underlines the need for close clinical vigilance of disease activity and infections during treatment.

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

Objective

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

Methods

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

Results

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

Conclusion

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

A New Paradigm in Spinal Cord Injury Therapy: from Cell-free Treatment to Engineering Modifications

Spinal cord injury (SCI) is an intractable and poorly prognostic neurological disease, and current treatments are still unable to cure it completely and avoid sequelae. Extracellular vesicles (EVs), as important carriers of intercellular communication and pharmacological effects, are considered to be the most promising candidates for SCI therapy because of their low toxicity and immunogenicity, their ability to encapsulate endogenous bioactive molecules (e.g., proteins, lipids, and nucleic acids), and their ability to cross the blood-brain/cerebrospinal barriers. However, poor targeting, low retention rate, and limited therapeutic efficacy of natural EVs have bottlenecked EVs-based SCI therapy. A new paradigm for SCI treatment will be provided by engineering modified EVs. Furthermore, our limited understanding of the role of EVs in SCI pathology hinders the rational design of novel EVbased therapeutic approaches. In this study, we review the pathophysiology after SCI, especially the multicellular EVs-mediated crosstalk; briefly describe the shift from cellular to cell-free therapies for SCI treatment; discuss and analyze the issues related to the route and dose of EVs administration; summarize and present the common strategies for EVs drug loading in the treatment of SCI and point out the shortcomings of these drug loading methods; finally, we analyze and highlight the feasibility and advantages of bio-scaffold-encapsulated EVs for SCI treatment, providing scalable insights into cell-free therapy for SCI.

Optimizing the diagnostic performance of neural antibody testing for paraneoplastic and autoimmune encephalitis in clinical practice

The detection of neural antibodies in patients with paraneoplastic and autoimmune encephalitis has majorly advanced the diagnosis and management of neural antibody-associated diseases. Although testing for these antibodies has historically been restricted to specialized centers, assay commercialization has made this testing available to clinical chemistry laboratories worldwide. This improved test accessibility has led to reduced turnaround time and expedited diagnosis, which are beneficial to patient care. However, as the utilization of these assays has increased, so too has the need to evaluate how they perform in the clinical setting. In this chapter, we discuss assays for neural antibody detection that are in routine use, draw attention to their limitations and provide strategies to help clinicians and laboratorians overcome them, all with the aim of optimizing neural antibody testing for paraneoplastic and autoimmune encephalitis in clinical practice.

Myelin insults differentials on MRI in children: In the light of an ADEM case

Acute disseminated encephalomyelitis (ADEM) is an acute and rapidly progressive auto-immune demyelinating disorder in the central nervous system. It is a rare disease but is more frequently observed in the pediatric population. We report a case of a monophasic postvaccination ADEM, which presented with paraparesis associated with fever. It showed a favorable evolution under corticosteroids, without recurrence after 3 years of follow-up. The diagnosis was established due to the postvaccination context and the MRI abnormalities characteristics. This case prompted a general discussion about the etiologies of myelin insults in children, especially demyelinating disorders, by shedding the light on their MRI features.

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.

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.

An engineered Fc fusion protein that targets antigen-specific T cells and autoantibodies mitigates autoimmune disease

Current effective therapies for autoimmune diseases rely on systemic immunomodulation that broadly affects all T and/or B cell responses. An ideal therapeutic approach would combine autoantigen-specific targeting of both T and B cell effector functions, including efficient removal of pathogenic autoantibodies. Albeit multiple strategies to induce T cell tolerance in an autoantigen-specific manner have been proposed, therapeutic removal of autoantibodies remains a significant challenge. Here, we devised an approach to target both autoantigen-specific T cells and autoantibodies by producing a central nervous system (CNS) autoantigen myelin oligodendrocyte glycoprotein (MOG)-Fc fusion protein. We demonstrate that MOG-Fc fusion protein has significantly higher bioavailability than monomeric MOG and is efficient in clearing anti-MOG autoantibodies from circulation. We also show that MOG-Fc promotes T cell tolerance and protects mice from MOG-induced autoimmune encephalomyelitis. This multipronged targeting approach may be therapeutically advantageous in the treatment of autoimmunity.

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..

Microfibrillar-associated protein 4 as a potential marker of acute relapse in inflammatory demyelinating diseases of the central nervous system: Pathological and clinical aspects

BACKGROUND

Microfibrillar-associated protein 4 (MFAP4) is an extracellular matrix protein not previously described in the human central nervous system (CNS).

OBJECTIVES

We determined MFAP4 CNS expression and measured cerebrospinal fluid (CSF) and serum levels.

METHODS

Tissue was sampled at autopsy from patients with acute multiple sclerosis (MS) (n = 3), progressive MS (n = 3), neuromyelitis optica spectrum disorder (NMOSD) (n = 2), and controls (n = 9), including 6 healthy controls (HC). MFAP4 levels were measured in 152 patients: 49 MS, 62 NMOSD, 22 myelin oligodendrocyte glycoprotein-associated disease (MOGAD), and 19 isolated optic neuritis (ION).

RESULTS

MFAP4 localized to meninges and vascular/perivascular spaces, intense in the optic nerve. At sites of active inflammation, MFAP4 reactivity was reduced in NMOSD and acute MS and less in progressive MS. CSF MFAP4 levels were reduced during relapse and at the onset of diseases (mean U/mL: MS 14.3, MOGAD 9.7, and ION 14.6 relative to HC 17.9. (p = 0.013, p = 0.000, and p = 0.019, respectively). Patients with acute ON (n = 68) had reduced CSF MFAP4 (mean U/mL: 14.5, p = 0.006). CSF MFAP4 levels correlated negatively with relapse severity (rho = -0.41, p = 0.017).

CONCLUSION

MFAP4 immunoreactivity was reduced at sites of active inflammation. CSF levels of MFAP4 were reduced following relapse and may reflect disease activity.

A Quality Assessment of Aquaporin-4 & Myelin Oligodendrocyte Glycoprotein Antibody Testing

BACKGROUND

Accurate anti-aquaporin-4 (AQP4) and anti-myelin oligodendrocyte glycoprotein (MOG) autoantibody assays are needed to effectively diagnose neuromyelitis optica spectrum disorder and MOG antibody-associated disease. A proportion of patients at our centre have been tested for anti-AQP4 and anti-MOG autoantibodies locally, followed by an outsourced test as part of real-world practice. Outsourced testing is costly and of unproven utility. We conducted a quality improvement project to determine the value of outsourced testing for anti-AQP4 and anti-MOG autoantibodies.

METHODS

All patients seen by Calgary neurological services who underwent cell-based testing for anti-AQP4 and/or anti-MOG autoantibodies at both MitogenDx (Calgary, AB) and Mayo Clinic Laboratories (Rochester, MN, USA) between 2016 and 2020 were identified from a provincial database. The interlaboratory concordance was calculated by pairing within-subject results collected no more than 365 days apart. Retrospective chart review was done for subjects with discordant results to determine features associated with discordance and use of outsourced testing.

RESULTS

Fifty-seven anti-AQP4 and 46 anti-MOG test pairs from January 2016 to July 2020 were analyzed. Concordant tests pairs comprised 54/57 (94.7%, 95%CI 88.9-100.0%) anti-AQP4 and 41/46 (89.1%, 95%CI 80.1-98.1%) anti-MOG results. Discordant anti-AQP4 pairs included two local weak positives (negative when outsourced) and one local negative (positive when outsourced). Discordant anti-MOG pairs were all due to local weak positives (negative when outsourced).

CONCLUSION

Interlaboratory discordant results for cell-based testing of anti-AQP4 autoantibodies were rare. Local anti-MOG weak positive results were associated with discordance, highlighting the need for cautious interpretation based on the clinical context. Our findings may reduce redundant outsourced testing.

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.

Neuromyelitis Optica Spectrum Disorder

Neuromyelitis optica spectrum disorder (NMOSD) is an autoimmune condition characterized by recurrent episodes of optic neuritis (ON) and transverse myelitis. This case report aims to highlight the importance of considering atypical presentations of NMOSD when confronted with MRI-detected Wernicke's encephalopathy. The primary target in NMOSD is the aquaporin-4 (AQP4) protein, predominantly located on astrocyte surfaces. Antibodies binding to AQP4 can lead to astrocyte dysfunction and damage, contributing to NMOSD's distinctive pathology. The associated immune response and inflammation can cause secondary harm to various components of the central nervous system, including oligodendrocytes and neuronal axons. This inflammatory process results in perivascular demyelination and axonal injury, further aggravating neurological deficits in NMOSD. In this case, we present a 39-year-old female with no prior medical or surgical history who sought medical attention due to a three-week history of progressive eyelid heaviness and somnolence. NMOSD is an autoimmune condition primarily targeting the AQP4 protein, resulting in recurrent ON and transverse myelitis. The patient was initially misdiagnosed with myasthenia gravis due to somnolence and ptosis. Due to concerns about myasthenia gravis due to diffuse fatigue and bilateral ptosis, the patient was initially treated with intravenous immunoglobulin (IVIG) and admitted to the neurology service. On the first day of her hospitalization, MRI with and without contrast revealed extensive, non-enhancing T2-weighted-fluid-attenuated inversion recovery (T2-FLAIR) hyperintensities surrounding the third ventricle and affecting the periaqueductal grey, medial thalami, and mammillary bodies. There was also an interval increase in T2-FLAIR hyperintensity within the right medial temporal lobe, extending more posteriorly and inferiorly, abutting the temporal horn. Subsequent CSF encephalitis panel results showed positive West Nile virus (WNV) IgG but negative WNV IgM, and AQP4 antibodies were positive. Given the high specificity of AQP4 antibodies, the patient was diagnosed with neuromyelitis optica (NMO) encephalitis. This case underscores the importance of considering atypical presentations of NMO when confronted with MRI-detected Wernicke's encephalopathy. Since our patient primarily displayed somnolence and eye-related symptoms, neither NMO nor Wernicke's encephalopathy were initially considered in the differential diagnosis. Furthermore, despite MRI findings suggestive of Wernicke's encephalopathy, it was considered less likely due to the absence of thiamine deficiency and consistent denials by family members regarding alcohol use, gastrointestinal issues, or inadequate oral intake. This case underscores the importance of considering NMOSD in patients with atypical symptoms, even when initial presentations suggest other conditions. Timely diagnosis is crucial to prevent mismanagement and improve patient outcomes. Clinicians should maintain a high level of suspicion for NMOSD, especially when MRI findings do not align with the initial diagnosis, as early recognition and treatment can significantly impact patient care and prognosis.

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.

Distinct features of B cell receptors in neuromyelitis optica spectrum disorder among CNS inflammatory demyelinating diseases

BACKGROUND

Neuromyelitis optica spectrum disorder (NMOSD) stands out among CNS inflammatory demyelinating diseases (CIDDs) due to its unique disease characteristics, including severe clinical attacks with extensive lesions and its association with systemic autoimmune diseases. We aimed to investigate whether characteristics of B cell receptors (BCRs) differ between NMOSD and other CIDDs using high-throughput sequencing.

METHODS

From a prospective cohort, we recruited patients with CIDDs and categorized them based on the presence and type of autoantibodies: NMOSD with anti-aquaporin-4 antibodies, myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) with anti-myelin oligodendrocyte glycoprotein antibodies, double-seronegative demyelinating disease (DSN), and healthy controls (HCs). The BCR features, including isotype class, clonality, somatic hypermutation (SHM), and the third complementarity-determining region (CDR3) length, were analyzed and compared among the different disease groups.

RESULTS

Blood samples from 33 patients with CIDDs (13 NMOSD, 12 MOGAD, and 8 DSN) and 34 HCs were investigated for BCR sequencing. Patients with NMOSD tended to have more activated BCR features compare to the other disease groups. They showed a lower proportion of unswitched isotypes (IgM and IgD) and a higher proportion of switched isotypes (IgG), increased clonality of BCRs, higher rates of SHM, and shorter lengths of CDR3. Notably, advanced age was identified as a clinical factor associated with these activated BCR features, including increased levels of clonality and SHM rates in the NMOSD group. Conversely, no such clinical factors were found to be associated with activated BCR features in the other CIDD groups.

CONCLUSIONS

NMOSD patients, among those with CIDDs, displayed the most pronounced B cell activation, characterized by higher levels of isotype class switching, clonality, SHM rates, and shorter CDR3 lengths. These findings suggest that B cell-mediated humoral immune responses and characteristics in NMOSD patients are distinct from those observed in the other CIDDs, including MOGAD. Age was identified as a clinical factor associated with BCR activation specifically in NMOSD, implying the significance of persistent B cell activation attributed to anti-aquaporin-4 antibodies, even in the absence of clinical relapses throughout an individual's lifetime.

Myelin oligodendrocyte glycoprotein antibody-associated optic neuritis in a post-COVID-19 infection patient

PURPOSE

SARS-CoV-2 viral infection affects multiple systems including the respiratory, gastrointestinal, neurological, cardiac, and ophthalmic systems. We report a case of myelin oligodendrocyte glycoprotein (MOG) related optic neuritis in a SARS-CoV-2 (COVID-19) patient.

METHODS

Case report.

RESULTS

A 36-year-old Malay gentleman with underlying hypertension presented with the first episode of bilateral progressively worsening blurred vision for 1 week associated with retrobulbar pain. There were no other neurological symptoms. He had fever a week before the eye symptoms and tested positive for COVID-19. He received COVID-19 booster vaccine a month before the disease onset. On examination, his vision was hand motion on right eye and 6/18 on left eye. Relative afferent pupillary defect (RAPD) was positive on right eye with abnormal optic nerve function tests. Anterior segments were unremarkable. Fundus examination showed bilateral optic disc swelling. MRI revealed multifocal hyperintense subcortical white matter lesions. Optic nerves appeared normal with no enhancement seen. Blood investigation showed a positive serum MOG antibody. Intravenous methylprednisolone was commenced followed by oral prednisolone after which his vision and ocular symptoms markedly improved. The oral prednisolone was tapered alongside addition of azathioprine. At 1 month, the disease was stable with no recurrence.

CONCLUSION

While optic neuritis has been associated with both COVID-19 infection and vaccination, MOG IgG antibody-mediated optic neuritis is also a possible manifestation. This type of optic neuritis associated with COVID-19 infection does not show a similar pattern of frequent recurrences as seen in non-COVID-19 related optic neuritis.

Fulminant Anti-Myelin Oligodendrocyte Glycoprotein-Associated Cerebral Cortical Encephalitis: Case Series of a Severe Pediatric Myelin Oligodendrocyte Glycoprotein Antibody-Associated Disease Phenotype

BACKGROUND

We describe a cohort of children with severe myelin oligodendrocyte glycoprotein (MOG)-IgG-associated cerebral cortical encephalitis (CCE), manifesting with bilateral cortical cytotoxic edema and critical neurological illness.

METHODS

We retrospectively reviewed our pediatric MOG antibody-associated disease (MOGAD) database and identified patients with specific radiographic pattern of bilateral, multifocal cortical cytotoxic lesions. We collected demographic, clinical, and outcomes data from these patients and compared select variables with radiographically distinct cerebral MOGAD syndromes (case-control analysis). We assessed the correlation of quantitative clinical variables with severity/outcomes measures using simple linear regression.

RESULTS

Sixty-five of 88 total MOGAD cases had cerebral disease, and six of 88 met inclusion criteria for fulminant CCE (f-CCE). Age range was 2 to 7 years; five of six were male. Six of six were critically ill with severe encephalopathy and seizures, two of six required barbiturate coma, and two of six required invasive intracranial pressure monitoring. Six of six required treatment escalation beyond steroids. Four of six had favorable outcome; two of six had moderate-severe disability. Compared with other cerebral MOGAD cases (n = 59), children with f-CCE were more likely to have critical illness and poor neurological outcomes scores. Neurofilament light chain and treatment latency positively correlated with intensive care unit length of stay and outcomes scores; cerebrospinal fluid (CSF) white blood cell count and neutrophil-to-lymphocyte ratio did not.

CONCLUSIONS

Pediatric CCE with bilateral cytotoxicity is associated with more fulminant disease and worse outcomes than other cerebral MOGAD syndromes.

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.

Central nervous system complications in SARS-CoV-2-infected patients

OBJECTIVE

To investigate the clinical manifestations, treatment and prognosis of COVID-19-associated central nervous system (CNS) complications.

METHODS

In this single-centre observation study, we recruited patients with COVID-19-associated CNS complications at the neurology inpatient department of the Eighth Affiliated Hospital, Sun Yat-Sen University (Futian, Shenzhen) from Dec 2022 to Feb 2023. Patients were analysed for demographics, clinical manifestations, cerebrospinal fluid properties, electroencephalographic features, neuroimaging characteristics, and treatment outcome. All patients were followed-up at 1 and 2 months after discharge until Apr 2023.

RESULTS

Of the 12 patients with COVID-19-associated CNS complications, the CNS symptoms occur between 0 days and 4 weeks after SARS-CoV-2 infection. The most common CNS symptoms were memory deficits (4/12, 33%), Unresponsiveness (4/12, 33%), mental and behavioural disorders (4/12, 33%). Seven of 12 cases can be categorized as probable SARS-CoV-2 encephalitis, and 5 cases can be described as brainstem encephalitis, acute disseminated encephalomyelitis, optic neuritis, multiple sclerosis or tremor probably associated with SARS-CoV-2 infection. Six patients received antiviral therapy, and 11 patients received glucocorticoid therapy, of which 3 patients received human immunoglobulin synchronously. Nine patients recovered well, two patients had residual neurological dysfunction, and one patient passed away from complications associated with tumor.

CONCLUSION

In this observational study, we found that the inflammatory or immune-related complications were relatively common manifestations of COVID-19-associated CNS complications, including different phenotypes of encephalitis and CNS inflammatory demyelinating diseases. Most patients recovered well, but a few patients had significant neurological dysfunctions remaining.

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.