MOG encephalomyelitis: international recommendations on diagnosis and antibody testing

Abnormal Brain MRI in Anti-NMDA Receptor Encephalitis: Clinical and Prognostic Implications

BACKGROUND AND OBJECTIVES

Abnormal brain MRI is associated with poor outcomes in anti-N-methyl-d-aspartate receptor encephalitis (NMDARE). We aimed to characterize the lesions on brain MRI in NMDARE and to assess the clinical and prognostic associations.

METHODS

This retrospective cohort study included patients with NMDARE identified at the French Reference Center for Autoimmune Encephalitis, with at least a one-year follow-up, and with available brain MRI results. In case of brain extralimbic lesion, the image files were reviewed when available. Clinical data were collected from medical records. Multivariable logistic regression analysis was used to study the outcomes at 2-year follow-up; recovery was defined as modified Rankin Scale score ≤1.

RESULTS

Among the 255 patients included, 37 (14.5%) had limbic hyperintensities and 41 (16.1%) had extralimbic lesions that included multiple sclerosis (MS)-like lesions (14/41, 34.1%); extensive lesions (5/41, 12.2%); and poorly demarcated fluffy lesions, either multifocal (10/41, 24.4%) or involving the cerebral cortex or cerebellum (6/41 each, 14.6%). Extralimbic lesions coexisting with limbic lesions (19/41 patients, 46.3%) were mostly fluffy lesions (11/19, 57.9%). Ten patients had overlapping demyelinating syndromes: 4 with MS, 4 with myelin oligodendrocyte glycoprotein-associated disorder, and 2 with neuromyelitis optica spectrum disorder; all had MS-like (7/10 patients) or extensive (3/10 patients) lesions, and none had fluffy lesions. Extralimbic lesions were associated with symptoms nontypical for NMDARE (23/41, 56.1%, p < 0.001), especially cerebellar ataxia (17/41, 41.5%) and motor impairment (12/41, 29.3%). At 2 years, patients with MS-like or extensive lesions had a lower recovery rate (5/12, 41.7%, and 1/4, 25%, respectively) compared with the patients without extralimbic lesions (124/162, 76.5%; p = 0.014 and p = 0.047, respectively). In multivariable analysis, MS-like lesions, but not hippocampal nor fluffy lesions, were associated with absence of recovery at 2 years (adjusted OR 0.1, 95% CI 0.03-0.42, p = 0.002; extensive lesions [n = 4] not included in the analysis).

DISCUSSION

Brain MRI lesions in NMDARE include limbic hyperintensities and 3 patterns of extralimbic lesions, which are associated with nontypical NMDARE symptoms. Moreover, MS-like and extensive lesions, but not fluffy nor hippocampal lesions, are associated with overlapping demyelinating syndromes and poor clinical outcomes at 2 years. These findings can have practical implications on the monitoring of patients with NMDARE.

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.

Review of atypical optic neuritis

Optic neuritis (ON), an inflammatory optic neuropathy, is among the most common causes of visual loss. In its initial clinical appearance, ON may have unilateral or bilateral presentation, and anterior (papillitis) or retrobulbar localization. Traditionally, cases are divided into typical and atypical ON. In the Western hemisphere, most typical cases of optic nerve inflammation are associated with multiple sclerosis (MS). However, ON may also be associated with a series of disorders of known or initially undetected origin. Atypical ON has a somewhat different clinical picture from typical ON, and encompasses neuromyelitis optica spectrum disease (NMOSD), myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD), idiopathic recurrent neuroretinitis (NR), chronic relapsing inflammatory ON (CRION), ON within systemic autoimmune diseases, paraneoplastic and neuritis during or after infectious diseases or vaccination. The causes should be meticulously worked up, to address the therapeutic and prognostic challenges posed by these conditions. Here, we provide a brief overview of atypical ON, as encountered in our clinical practice, and additionally discuss the possible occurrence of optic neuropathies other than inflammatory and other ocular diseases within these disorders.

Unravelling the clinical complexity of myelin oligodendrocyte glycoprotein antibody-associated acute disseminated encephalomyelitis in children: a comprehensive analysis

We present four different cases of acute disseminated encephalomyelitis (ADEM) within the Indian paediatric population. It is important to recognise how a single disease can manifest in various ways. Here, we emphasise the role of immunosuppression in treating ADEM. In all four cases, treatment was initiated based on clinical suspicion, even before confirming the demyelinating cause through laboratory or radiological tests. The degree of immunosuppression employed varied depending on the complexity of each case and their response to treatment. Case 1 demonstrated significant improvement in visual acuity after a 5-day course of high-dose methylprednisolone. In contrast, Case 4 represented a starkly different outcome, where despite undergoing therapeutic plasmapheresis, the disease remained uncontrollable, ultimately leading to the child's unfortunate demise. Cases 2 and 3 involved patients with severe clinical conditions necessitating intensive care and mechanical ventilation. They exhibited a remarkable response to immunosuppressive therapy, gradually regaining neurological function.

Clinical characterization of diseases associated with anti-N-methyl-D-aspartate receptor encephalitis combined with anti-myelin oligodendrocyte glycoprotein antibodies in adults

OBJECTIVE

The aim of this study was to analyze the clinical characteristics of adult patients with anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis combined with anti-myelin oligodendrocyte glycoprotein (MOG) antibodies.

METHODS

This was a non-randomized controlled study. Clinical data were collected from 17 patients with anti-NMDAR encephalitis combined with anti-MOG antibodies admitted to Xuanwu Hospital, Capital Medical University, from January 2020 to August 2024. As controls, 20 patients with NMDAR(+)/MOG(-) and 27 patients with MOG(+)/NMDAR(-) were selected.

RESULTS

The mean age of onset in the double-positive group was 33.47 ± 1.065 years, with a male-to-female ratio of 14:3. Significant differences were observed between the NMDAR(+)/MOG(+) group and the NMDAR(+)/MOG(-) group in terms of headache, lumbar puncture pressure, and cerebrospinal fluid (CSF) leukocyte counts (P < 0.05). Comparing the NMDAR(+)/MOG(+) group with the MOG(+)/NMDAR(-) group revealed significant differences in gender, headache, mental and behavioral abnormalities, limb twitching, loss of consciousness, cognitive impairment, speech impairment, visual impairment, limb numbness, cortical/sub-cortical white matter, brainstem lesions, OB type II, and CSF leukocyte counts (P < 0.05). No statistically significant differences were found in the comparison of CSF and serum antibody titers among the three groups (P > 0.05).

CONCLUSION

NMDAR and MOG antibodies can coexist in patients with autoimmune diseases, with a predominance of young male patients. The double-positive group exhibited more severe intracranial viral infections and a higher rate of intrathecal immunoglobulin synthesis in the central tissues. Compared to the double-positive group, NMDAR encephalitis alone presented with more similar clinical manifestations, while MOG-related disease demonstrated a higher likelihood of brainstem involvement.

Broader anti-EBV TCR repertoire in multiple sclerosis: disease specificity and treatment modulation

Epstein-Barr virus (EBV) infection has long been associated with the development of multiple sclerosis (MS). Patients with MS have elevated titres of EBV-specific antibodies in serum and show signs of CNS damage only after EBV infection. Regarding CD8+ T cells, an elevated but ineffective response to EBV was suggested in MS patients, who present with a broader MHC-I-restricted EBV-specific T-cell receptor beta chain (TRB) repertoire compared to controls. It is not known whether this altered EBV response could be subject to dynamic changes, e.g. by approved MS therapies, and whether it is specific for MS. Peripheral blood TRB repertoire samples (n = 1317) of healthy donors (n = 409), patients with MS (n = 710) before and after treatment, patients with neuromyelitis optica spectrum disorder (n = 87), MOG antibody-associated disease (MOGAD) (n = 64) and Susac's syndrome (n = 47) were analysed. Apart from MS, none of the evaluated diseases presented with a broader anti-EBV TRB repertoire. In MS patients undergoing autologous haematopoietic stem-cell transplantation, EBV reactivation coincided with elevated MHC-I-restricted EBV-specific TRB sequence matches. Therapy with ocrelizumab, teriflunomide or dimethyl fumarate reduced EBV-specific, but not CMV-specific MHC-I-restricted TRB sequence matches. Together, these data suggest that the aberrant MHC-I-restricted T-cell response directed against EBV is specific to MS with regard to neuromyelitis optica, MOGAD and Susac's syndrome and that it is specifically modified by MS treatments interfering with EBV host cells or activated lymphocytes.

Can serum C3/C4 complement ratio be used in the differential diagnosis of central nervous system demyelinating diseases?

BACKGROUND

Neuromyelitis Optica Spectrum Disorders (NMOSD) and Multiple Sclerosis (MS) are primary demyelinating diseases of the central nervous system (CNS) with similar clinical features, complicating early differential diagnosis and treatment decisions. While both humoral and cellular immunity contribute to their immunopathogenesis, the complement system's role remains unclear. We considered complement-dependent cytotoxicity might have different roles in the pathophysiology of these diseases. Predictive value of C3 and C4 complement levels at the first attack for the definitive diagnosis aimed to be investigated.

METHODS

Treatment-naive, 14 seronegative (SN) NMO, 28 aquaporin-4-positive [AQP4(+)] NMO, 23 myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD), and 15 MS adult patients were included. Serum C3 and C4 levels were evaluated retrospectively. Complement levels were statistically adjusted according to the age of the patients and C3/C4 ratio was used to increase statistical power.

RESULTS

We found that C4 levels were lower and C3/C4 ratio was higher in SNNMO and AQP4(+)-NMO groups compared to the MS group. It has been determined that 5.32 and 4.85 cut-off values of the C3/C4 ratio can discriminate SNNMO and AQP4(+)-NMO groups from MS.

CONCLUSION

The classical complement pathway in SNNMO and AQP4(+)-NMO was thought to be more affected compared to MS, as activation of the classical pathway predominantly decreases the level of C4. Since the involvement of the complement system pathways at different levels may be presented with the C3/C4 ratio, it seems likely that this ratio may have value as a candidate biomarker in the differential diagnosis of primary CNS demyelinating diseases.

MRI-based radiomics for differention of aquaporin 4-immunoglobulin G-positive neuromyelitis optic spectrum disorder and anti myelin oligodendrocyte glycoprotein immunoglobulin G-associated disorder

OBJECTIVES

This study was designed to develop and validate a radiomic nomogram for the differential diagnosis of myelin oligodendrocyte glycoprotein antibody-related disease (MOGAD) and aquaporin-4 immunoglobulin G-positive neuromyelitis optica spectrum disorder (AQP4+NMOSD).

METHODS

We retrospectively analysed data from a primary cohort consisting of 21 MOGAD and 63 AQP4+NMOSD patients and an external validation cohort comprising 10 MOGAD and 34 AQP4+NMOSD patients. Radiomic features were extracted from lesions of the cervical spinal cord and brainstem from sagittal T2-weighted MR images. We constructed a prediction model by integrating radiomic features with clinical data and evaluated its performance using calibration curves and decision curve analysis (DCA).

RESULTS

We developed a comprehensive nomogram that combines clinical and radiomic features to distinguish MOGAD from AQP4+NMOSD. The discriminative ability of the nomogram was quantified by the area under the receiver operating characteristic (ROC) curve (AUC), achieving values of 0.915 (95 % CI, 0.859-0.970) in the primary cohort and 0.837 (95 % CI, 0.715-0.959) in the validation cohort, indicating high diagnostic accuracy. The calibration analyses showed good concordance between the model predicted and actual outcomes.

CONCLUSIONS

This study successfully validated the radiomic feature model, demonstrating its superior performance in differentiating MOGAD from AQP4+NMOSD. The nomogram, integrating radiomic features with conventional imaging characteristics of brainstem and cervical cord lesions, significantly enhanced differentiation capability. Both models proved valuable in improving diagnostic accuracy, with radiomic features contributing most significantly.

Neurite orientation dispersion and density imaging in myelin oligodendrocyte glycoprotein antibody-associated disease and neuromyelitis optica spectrum disorders

BACKGROUND

Aquaporin-4 antibody positive (AQP4+) neuromyelitis optica spectrum disorders (NMOSD) and myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) are two distinct antibody-mediated neuroinflammatory diseases. Diffusion Tensor Imaging (DTI) and Neurite Orientation Dispersion and Density Imaging (NODDI) are advanced diffusion-weighted MRI models providing quantitative metrics sensitive to cerebral microstructural changes. This study aims to differentiate brain tissue damage in NMOSD and MOGAD from controls and investigate its association with clinical disability, using NODDI and DTI-derived measures, including fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD) and radial diffusivity.

METHODS

This study included 31 AQP4+ NMOSD, 21 MOGAD patients and 45 healthy controls. Clinical information included disease duration, Expanded Disability Status Scale (EDSS), Timed 25 Foot Walk test (T25FW), Nine-Hole Peg Test (9HPT), Symbol Digit Modalities Test (SDMT) and monocular 100 % high contrast visual acuity (HCVA). All participants underwent MRI scanning with multi-shell diffusion-weighted imaging, T2w fluid-attenuated inversion recovery and T1w magnetization prepared-rapid acquisition gradient echo sequences to obtain manually segmented T2-hyperintense white matter lesions (WML) and normal-appearing brain tissue (NABT) masks, including white matter (NAWM), cortical and deep gray matter (NACGM, NADGM). DTI and NODDI metrics were compared between groups using region-of-interest (ROI) analysis and tract-based spatial statistics. Tissue-weighted means were obtained for the NODDI metrics (weighted neurite density index, wNDI; weighted orientation dispersion index, wODI). Group differences in ROI analyses were assessed using age and sex adjusted linear regression models, followed by post-hoc comparisons with estimated marginal means. Stepwise multivariable linear regression models were used to evaluate the association between MRI biomarkers and clinical outcomes.

RESULTS

NMOSD patients had higher T2 lesion volume (1120.5 mm3 vs. 374.6 mm3, p<.001) and number (median 22 vs. 6, p<.001) than MOGAD patients. Both NMOSD and MOGAD lesions displayed lower wNDI and higher isotropic volume fraction (ISOVF) compared to microvascular lesions in controls (p<.05). In NACGM, NMOSD patients showed higher wODI but lower ISOVF compared to HC (p=.029). MOGAD patients had lower wNDI in NACGM compared to NMOSD (p=.012). Tract-based spatial statistics revealed damage to specific white matter abnormalities in NMOSD, with higher AD, ODI and ISOVF compared to controls, particularly in the corpus callosum and corticospinal tract. Clinical associations in NMOSD included higher EDSS with higher NAWM ISOVF (R2=0.46, p=.006), higher 9HPT with lower intralesional FA and higher NAWM MD (R2=0.54, p=.022), lower SDMT with lower intralesional FA and higher NACGM ISOVF (R2=0.54, p=.013), worse visual acuity with higher NAWM wODI. In MOGAD, higher EDSS was associated with lower NAWM FA (R2=0.29, p=.022), slower T25FW with higher NADGM ISOVF (R2=0.48, p<.001), lower SDMT with higher NAWM ISOVF (R2=0.62, p=.005) and worse visual acuity with higher NADGM MD.

CONCLUSION

NODDI and DTI measures are sensitive to pathological alterations in myelin and axon integrity, as water diffusion is less restricted in demyelinated tissue. Compared to MOGAD, patients with NMOSD tend to exhibit more extensive chronic white matter damage, demyelination or axonal injury. NODDI demonstrates greater sensitivity and specificity to alterations in NACGM compared to DTI. Given their association with clinical disability, NODDI metrics appear to be valuable neuroimaging biomarkers for assessing microstructural damage in clinical research.

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.

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.

Approach to Managing the Initial Presentation of Multiple Sclerosis: A Worldwide Practice Survey

Background and Objectives

Available disease-modifying therapies (DMTs) for multiple sclerosis (MS) are rapidly expanding; although escalation approaches aim to balance safety and efficacy, emerging evidence suggests superior outcomes for people with MS who are exposed to early high-efficacy therapies. We aimed to explore practice differences in prevailing management strategies for relapsing-remitting MS.

Methods

We used a worldwide electronic survey launched by the Practice Current section of Neurology® Clinical Practice. Questions pertained to a case of a 37-year-old woman presenting with optic neuritis. Respondents were asked to indicate their initial investigations, relapse management strategy, choice of disease-modifying therapy, and plan for follow-up imaging (contrast/noncontrast). Survey responses were stratified by key demographic variables along with 95% confidence intervals (95% CIs).

Results

We received 153 responses from 42 countries; 32.3% responders identified as MS specialists. There was a strong preference for intravenous delivery of high-dose corticosteroids (87.7%, 95% CI 80.7-92.5), and most of the responders (61.3%, 95% CI 52.6-69.4) indicated they would treat a nondisabling (mild sensory) MS relapse. When asked to select a single initial DMT, 56.6% (95% CI 47.6-65.1) selected a high-efficacy therapy (67.5% MS specialists vs 53.7% non-MS specialists). The most selected agents overall were fingolimod (14.7%), natalizumab (15.5%), and dimethyl fumarate (20.9%). Two-thirds of respondents indicated they would request contrast-enhanced surveillance MRI.

Discussion

Although there is a slight preference for initiating high-efficacy DMT at the time of initial MS diagnosis, opinions regarding the most appropriate treatment paradigm remain divided.

The value of CSF diagnostic and prognostic biomarkers in NMOSD and MOGAD in real-life use

BACKGROUND

Diagnosing neuromyelitis optica spectrum disorder (NMOSD) may be challenging owing to overlapping clinical features with multiple sclerosis (MS) and myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD), particularly in AQP4-IgG seronegative NMOSD patients. We evaluated cerebrospinal fluid (CSF) biomarkers, specifically glial fibrillary acidic protein (GFAP) and albumin quotient (QAlb), to improve diagnostic accuracy in NMOSD.

METHODS

In this retrospective study, we analyzed CSF samples for biomarkers GFAP, QAlb, neurofilament light, and total-Tau, from patients with AQP4-NMOSD, DNNMOSD, MOGAD, and MS in the Region Västra Götaland, Sweden. Receiver operating characteristic (ROC) analysis with calculation of the area under the curve (AUC) was used to identify optimal cut-off levels for discriminating AQP4-NMOSD from the other groups. Logistic regression models assessed the diagnostic power of GFAP and QAlb combined.

RESULTS

Patients with AQP4-NMOSD (N = 19) had significantly higher CSF GFAP levels than the others: median 2470 ng/L vs 330 ng/L (p < 0.001). The GFAP cutoff >715 ng/L gave a sensitivity of 81 % and specificity of 92 %. Combining GFAP and QAlb further increased the diagnostic accuracy (AUC = 0.96). MOGAD patients (N = 29) had the highest CSF lymphocyte counts, with elevated lymphocyte counts correlating with polyphasic MOGAD (R = 0.63; p = 0.016).

CONCLUSION

CSF GFAP is a valuable biomarker for distinguishing AQP4-NMOSD from other demyelinating diseases: Combining GFAP with QAlb enhances diagnostic precision.

Performance of the 2023 diagnostic criteria for MOGAD: real-world application in a Chinese multicenter cohort of pediatric and adult patients

BACKGROUND

The clinical phenotypes of myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) have been found to overlap with several other diseases. The new criteria proposed in 2023 were designed to better identify the disease but require validation across various populations to ascertain its clinical utility. We aimed to investigate the diagnostic performance in phenotypically diverse patients.

METHODS

This multicenter study retrospectively included adult and pediatric patients who were hospitalized for a first suspected demyelinating event and tested positive for MOG immunoglobulin G (IgG) during the acute phase. The 2023 Lancet Neurology criteria were assessed against the benchmark of empirical clinical diagnosis, and the 2018 JAMA Neurology and Journal of Neuroinflammation criteria were also evaluated for comparative analysis.

RESULTS

Among the 291 eligible patients (82 adults, 209 children), 282 (96.9%) were clinically diagnosed as definite MOGAD (77 adults, 205 children), while 262 (90.0%) fulfilled the 2023 diagnostic criteria (78 adults, 184 children). A total of 265 patients met the criteria for core clinical demyelinating events, and 76 (26.1%) had serum clear positive MOG-IgG (≥ 1:100). The sensitivity of the 2023 criteria was 0.91 (adults vs. children = 0.97 vs. 0.89), the specificity was 0.56 (adults vs. children = 0.40 vs. 0.75), positive likelihood ratio was 2.06 (adults vs. children = 1.62 vs. 3.57), and negative likelihood ratio (NLR) was 0.15 (adults vs. children = 0.06 vs. 0.14). Additionally, 264 and 256 cases were classified as definite MOGAD by the 2018 JAMA Neurology and Journal of Neuroinflammation criteria, respectively. Compared to the 2023 diagnostic criteria, the 2018 JAMA Neurology criteria demonstrated similar diagnostic performance. However, the 2018 Journal of Neuroinflammation criteria exhibited comparable sensitivity (0.92, adults vs. children = 0.96 vs. 0.89), higher specificity (1.00, adults vs. children = 1.00 vs. 1.00) and better NLR (0.09, adults vs. children = 0.04 vs. 0.11).

CONCLUSIONS

The 2023 criteria demonstrated good sensitivity in adult and pediatric patients in China yet modest specificity. Close follow-up is needed for patients with atypical phenotypes but high-titer MOG-IgG to avoid underdiagnosis.

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.

Real-world multicentre cohort study on choices and effectiveness of immunotherapies in NMOSD and MOGAD

BACKGROUND

Recurrent attacks in neuromyelitis optica spectrum disorders (NMOSDs) or myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) can lead to severe disability. We aimed to analyse the real-world use of immunotherapies in patients with NMOSD and MOGAD, focusing on changes in treatment strategies, effects on attack rates (ARR) and risk factors for attacks.

METHODS

This longitudinal registry-based cohort study included 493 patients (320 with aquaporin-4 immunoglobulin G (AQP4-IgG) seropositive NMOSD (65%), 44 with AQP4-IgG seronegative NMOSD (9%) and 129 MOGAD (26%)) with 1247 treatments from 19 German and one Austrian centre from the registry of the neuromyelitis optica study group (NEMOS). We analysed unadjusted ARR and implemented survival analyses and Cox proportional hazard regression to assess efficiency and risk factors for subsequent attacks over time.

RESULTS

Rituximab and azathioprine are the most widely used immunotherapies in NMOSD as well as in MOGAD, with changes in distribution over the last decade. Immunotherapy demonstrated significant therapeutic effects in NMOSD but less pronounced effects in MOGAD. Risk factors for attacks included younger age and prior attacks under the same therapy. Efficacy varied among the different immunotherapies, with azathioprine, rituximab and eculizumab showing significant risk reductions in AQP4-IgG seropositive NMOSD.

CONCLUSIONS

This study provides insights into the evolving treatment landscape and effectiveness of immunotherapies in NMOSD and MOGAD. Established off-label therapies continue to play an important role, especially for patients with stable disease, with emerging evidence supporting newly approved therapies. Future studies are needed to refine treatment algorithms and address the ongoing uncertainties in MOGAD management.

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.

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.

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.

Prevalence of comorbid autoimmune diseases and antibodies in newly diagnosed multiple sclerosis patients

BACKGROUND

Diagnosing multiple sclerosis (MS) is challenging due to diverse symptoms and the absence of specific biomarkers. Concurrent autoimmune diseases (AID) or non-specific antibodies further complicate diagnosis, progression monitoring, and management. Data on AID prevalence in MS patients are sparse. This study aims to identify concurrent AIDs alongside MS.

METHODS

In this retrospective single-center study, we analyzed patient records at our university hospital from 2010 to 2017, focusing on cases suspected of inflammatory demyelinating disease. The 2017 McDonald criteria were applied. Additionally, we measured neurofilament light (NfL) levels from available CSF samples in our biobank.

RESULTS

We identified a total of 315 patients, of whom 66% were women. In total, 13.7% of all patients had concurrent AID, while 20.3% had isolated antibody findings without AID. The most common AID was autoimmune thyroiditis (8.9%), followed by chronic inflammatory skin diseases (1.6%), arthritis (1%), type 1 diabetes (1%), Sjögren's syndrome (0.6%), and inflammatory bowel diseases (0.6%). Cardiolipin antibodies were the most frequent isolated antibody finding (8.6%). Our data showed that, from the perspective of the initial demyelinating event, neither comorbid AID nor isolated antibodies significantly influenced relapses or MS progression over a median follow-up of 9 months. Standard CSF parameters and NfL levels were similar between the groups at the time of MS diagnosis.

CONCLUSION

Our study shows that AIDs, particularly autoimmune thyroiditis, frequently occur at the onset of MS. The proportion of AIDs commonly treated with immunomodulatory therapy in our cohort was similar to that observed in the general population. Comorbid AID did not affect NfL levels, indicating similar disease activity. Future research should explore new AID emergence during the course of MS, especially considering the increased incidence of rheumatic diseases later in life.

Cerebrospinal fluid neurofilament light chain levels in children with acquired demyelinating syndrome

Objective

To study the cerebrospinal fluid (CSF) neurofilament light chain (NfL) in pediatric acquired demyelinating syndrome (ADS) and its association with factors of laboratory and imaging results.

Methods

We analyzed clinical data from children with ADS collected from May 2020 to January 2021 at the Department of Neurology of Guangzhou Women and Children's Medical Center. Enzyme-linked immunosorbent assays were used to detect the CSF NfL of patients.

Results

Thirty pediatric ADS patients (17 male, 13 female) were included in the study. The most frequent diagnosis was uncategorized ADS (36.7%, 11/30), followed by acute disseminating encephalomyelitis (ADEM) (23.3%, 7/30), myelin oligodendrocyte glycoprotein antibody-associated disorder (MOGAD) (20.0%, 6/30), NMO (6.7%, 2/30), multiple sclerosis (MS) (6.7%, 2/30), and neuromyelitis optic spectrum disorders (NMOSD) (6.7%, 2/30). The median CSF NfL for the first time was 7,425.28 pg/ml (interquartile range, 1,273.51, >10,000 pg/ml). CSF NfL increase over normal value (<290.00 pg/ml for people younger than 30 years old) was seen in 98.7% of patients. Patients were divided into uncategorized ADS, ADEM, MOGAD, and MS/NMO/NMOSD groups, with no significant difference in CSF NfL between each group. The CSF NfL positively correlated with the immunoglobulin (Ig) G (ρ = 0.473) and IgE (ρ = 0.366). However, the CSF NfL did not correlate with CSF white blood count and CSF protein. Furthermore, there was no significant difference between patients with oligoclonal bands positive and without. The CSF NfL negatively correlated with interferon γ (ρ = -0.501), CD45 + CD3+ T (ρ = -0.466), CD45 + CD3 + CD4+ T (ρ = -0.466), and CD45 + CD3 + CD8+ T cells (ρ = -0.521). However, it did not correlate with CD45 + CD19+ B cells. CSF NfL in patients with cerebral white matter lesions in MRI was higher than in patients without. Moreover, the CSF NfL positively correlated with the number of brain MRI locations (ρ = 0.362). Nine patients underwent multiple detections of CSF NfL, and their CSF NfL for the last detection was not significantly different from the first.

Conclusions

The CSF NfL increases significantly in pediatric ADS, and it can be a biomarker of neuro-axonal injury and a good indication of the extent of lesions.

Rapid differentiation of MOGAD and MS after a single optic neuritis

BACKGROUND

Optic neuritis (ON) is a common manifestation of multiple sclerosis (MS) and myelin-oligodendrocyte-glycoprotein IgG-associated disease (MOGAD). This study evaluated the applicability of optical coherence tomography (OCT) for differentiating between both diseases in two independent cohorts.

METHODS

One hundred sixty two patients from seven sites underwent standard OCT and high-contrast visual acuity (HCVA) testing at least 6 months after first ON. Of these, 100 patients (32 MOGAD, 68 MS) comprised the primary investigational cohort, while 62 patients (31 MOGAD, 31 MS) formed a validation cohort. A composite score distinguishing between MOGAD and MS was developed using multivariate logistic regression.

RESULTS

Bilateral simultaneous ON occurred more frequently in MOGAD compared to MS (46.9 vs. 11.8%, p < 0.001). OCT revealed more peripapillary retinal nerve fiber layer (pRNFL) atrophy in all segments in MOGAD compared to predominantly temporal pRNFL atrophy in MS (p < 0.001). HCVA was better preserved in MS (p = 0.007). pRNFL thickness in all except for temporal segments was suitable for differentiating MOGAD and MS. Simultaneous bilateral ON and critical atrophy in nasal (< 58.5 µm) and temporal superior (< 105.5 µm) segments were included into the composite score as three independent predictors for MOGAD. The composite score distinguished MOGAD from MS with 75% sensitivity and 90% specificity in the investigational cohort, and 68% sensitivity and 87% specificity in the validation cohort.

CONCLUSION

Following a single ON-episode, MOGAD exhibits more pronounced global pRNFL atrophy and lower visual acuity after ON compared to MS. The introduced OCT-based composite score enabled differentiation between the two entities across both cohorts.

Clinical characteristics of double negative atypical inflammatory demyelinating disease: A prospective study

OBJECTIVE

This study aimed to investigate the clinical characteristics and predictors of relapse in double negative atypical inflammatory demyelinating disease (IDD) and to explore potential antigenic targets by tissue-based assays (TBA) using rat brain indirect immunofluorescence.

METHODS

We compared the clinical, laboratory, and MRI data of double negative atypical IDD with other IDD patients. Serum samples were collected for TBA. The predictors of relapse were examined over a minimum of 24 months follow-up.

RESULTS

In our cohort of 98 patients with double negative atypical IDD, there was no significant female predominance (58.2%, 57/98). The lesions primarily affected the spinal cord and brain stem, with fewer cases of involvement in the area postrema (5.1%, 5/98) and longitudinally extensive transverse myelitis (43.9%, 43/98). A total of 62.5% (50/80) patients tested positive for anti-astrocyte antibodies based on rat brain TBA. Over a median duration of 39.5 months, 80 patients completed the entire follow-up, and 47.5% (38/80) patients exhibited monophasic course. A total of 36% (18/50) patients positively for anti-astrocyte antibodies had a monophasic course, which is significantly lower than patients negatively for anti-astrocyte antibodies (66.7%, 20/30) (p = 0.008). The presence of anti-astrocyte antibodies (hazard ratio (HR), 2.243; 95% CI, 1.087-4.627; p = 0.029) and ≥4 cerebrum lesions at first attack (HR, 2.494; 95% CI, 1.224-5.078; p = 0.012) were risk factors for disease relapse, while maintenance immunotherapy during remission (HR, 0.361; 95% CI, 0.150-0.869; p = 0.023) was protective factor.

INTERPRETATION

Double negative atypical IDD are unique demyelinating diseases with a high relapse rate. Maintenance immunotherapy is helpful to the prevention of relapse, particularly in patients with anti-astrocyte antibodies or ≥4 cerebrum lesions at first attack.

A comparative study of hypothalamic involvement in patients with myelin oligodendrocyte glycoprotein antibody-associated disease, neuromyelitis optica spectrum disorder, and multiple sclerosis

BACKGROUND AND PURPOSE

We aimed to characterize hypothalamic involvement in myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) and compare it with neuromyelitis optica spectrum disorder (NMOSD) and multiple sclerosis (MS).

METHODS

A retrospective study was performed to identify hypothalamic lesions in patients diagnosed with MOGAD, NMOSD, or MS from January 2013 to May 2020. The demographic, clinical, and radiological features were recorded. Hypothalamic dysfunction and prognosis were assessed through physical examination, biochemical testing, sleep monitoring, and magnetic resonance imaging.

RESULTS

Hypothalamic lesions were observed in seven of 96 patients (7.3%) with MOGAD, 34 of 536 (6.3%) with NMOSD, and 16 of 356 (4.5%) with MS (p = 0.407). The time from disease onset to development of hypothalamic lesions was shortest in MOGAD (12 months). The frequency of bilateral hypothalamic lesions was the lowest in MOGAD (p = 0.008). The rate of hypothalamic dysfunction in MOGAD was 28.6%, which was lower than that in NMOSD (70.6%) but greater than that in MS patients (18.8%; p = 0.095 and p = 0.349, respectively). Hypothalamic dysfunction in MOGAD manifests as hypothalamic-pituitary-adrenal axis dysfunction and hypersomnia. The proportion of complete regression of hypothalamic lesions in MOGAD (100%) was much greater than that in NMOSD (41.7%) and MS patients (18.2%; p = 0.007 and p = 0.001, respectively). An improvement in hypothalamic dysfunction was observed in all MOGAD patients after immunotherapy.

CONCLUSIONS

MOGAD patients have a relatively high incidence of asymptomatic hypothalamic lesions. The overall prognosis of patients with hypothalamic involvement is good in MOGAD, as the lesions completely resolve, and dysfunction improves after immunotherapy.

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.

Assessment of international MOGAD diagnostic criteria in patients with overlapping MOG-associated disease and multiple sclerosis phenotypes

BACKGROUND

The clinical spectrum and diagnosis of myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) has evolved in the setting of an optimized anti-MOG-IgG cell-based assay and expert consensus. The McDonald criteria for MS have been revised multiple times to improve the accuracy and specificity of diagnosis on a framework based on clinical presentation, MRI findings, and CSF results. While the uses of MS and MOGAD diagnostic criteria are helpful for typical cases, such utility for patients with overlapping clinical, laboratorial, and imaging features is unknown, posing diagnostic and management uncertainties.

OBJECTIVES

To report a multicenter cohort of patients with overlapping phenotypic features of MOGAD and MS and evaluate the application of new MOGAD diagnostic criteria.

METHODS

A collaborative retrospective cohort study was performed to identify patients with both positive serum anti-MOG-IgG and fulfillment of the MS revised 2017 McDonald criteria. Clinical and radiographic features of patients fulfilling inclusion criteria were reviewed longitudinally, including relapses, repeated MRI, and MOG-IgG testing in detail to allow the panel of expert opinion to assign to each case. The International MOGAD Panel proposed criteria were applied at onset and last follow-up to each case and compared to the expert author diagnosis assignment based on presentation, clinical and imaging features, and response to treatment.

RESULTS

Ten of 225 (4%) MOG-IgG seropositive cases met study inclusion criteria [seven of 10 were female; age at initial event: eight adults (mean age 26.8 years), two adolescents (mean age 14.5 years)]. AQP4-IgG was negative for all. Apart from serum titers of MOG-IgG, distinguishing clinical and radiographic features [i.e., clinical severity of the initial demyelinating event, radiographic features (optic nerve/spine/brain), and presence/absence of lesion normalization on serial scans] led to consensus of three separate classifications differing by degrees of shared features of MOGAD and MS. Patients were classified by expert panel into (1) Classic MOGAD even with MS-like, well-defined brain lesions, when severe events and most T2 lesions normalized (n = 5; MOG-IgG titers 1:100, 1:20, 1:160, 1:40, 1:200); (2) Classic RRMS included cases thought to have likely false positive or clinically irrelevant MOG-IgG, due to mild clinical events and no radiographic normalization of well-defined MS-like lesions (n = 3; MOG titers 1:20, 1:100, 1:40); (3) MOGAD and MS overlapping phenotype was defined by those with a combination of mild and severe clinical events, partial T2 lesion normalization, both well- and ill-defined lesions (n = 2; MOG titers 1:20, 1:100). The application of the International MOGAD Panel criteria categorized five patients (50%) in agreement with expert assignment. One additional patient was classified in agreement to assignment when MOGAD criteria were applied after serial MOG-IgG titers testing.

DISCUSSION

While the International MOGAD Panel diagnostic criteria have helped with accuracy for the diagnosis of this condition, in a group of patients seropositive for MOG-IgG with overlapping clinical and imaging features of RRMS criteria review may lead to increased accuracy. Serial serologies, repeated imaging, close attention to clinical course, and response to therapy are possible variables to consider for further refinement of MOGAD diagnostic criteria.

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

INTRODUCTION

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Cortical atrophy patterns in myelin oligodendrocyte glycoprotein antibody-associated disease

OBJECTIVES

Global brain volume changes in patients with myelin oligodendrocyte glycoprotein antibody-associated disease compared with healthy controls (HC) could be revealed by magnetic resonance imaging, but specific atrophy patterns of cortical structures and relation to cognitive impairment are not yet comprehensively known. Thus, we aimed to investigate cortical thickness differences in patients with myelin oligodendrocyte glycoprotein antibody-associated disease compared with HC.

METHODS

3-Tesla brain magnetic resonance imaging was performed in 23 patients with myelin oligodendrocyte glycoprotein antibody-associated disease and 49 HC for voxel-wise group comparisons and neuropsychological testing in patients. Surface-based morphometry with region of interest-based surface analysis and region of interest-based extraction of cortical thickness was performed in patients compared with HC and in patient subgroups with and without cognitive impairment.

RESULTS

Comparing patients with myelin oligodendrocyte glycoprotein antibody-associated disease with HC, exploratory surface-based morphometry demonstrated cortical volume reduction in pericalcarine and lingual cortical regions. Region of interest-based surface analysis specified reduced cortical thickness in the adjacent pericalcarine and orbitofrontal regions in myelin oligodendrocyte glycoprotein antibody-associated disease, as well as reduced temporal cortical thickness in patients with cognitive impairment (n = 10). Patients without cognitive impairment (n = 13) showed only circumscribed cortical brain volume loss compared with HC in the pericalcarine region.

INTERPRETATION

In conclusion, cortical atrophy in myelin oligodendrocyte glycoprotein antibody-associated disease was characterized by cortical thickness reduction in the adjacent pericalcarine and orbitofrontal regions, with a tendency of temporal thickness reduction in cognitively impaired patients.

Longitudinal change of serum NfL as disease activity biomarker candidate in MOGAD: A descriptive cohort study

BACKGROUND

Myelin oligodendrocyte glycoprotein antibody (MOG-IgG)-associated disease (MOGAD) is an autoinflammatory disease of the central nervous system. MOGAD often follows a relapsing course that can lead to severe disability, but monophasic disease is possible as well. Currently, there is an unmet clinical need for disease activity biomarkers in MOGAD. Serum neurofilament light chain (sNfL) is a sensitive biomarker for neuroaxonal damage. However, data on longitudinal change of sNfL as disease activity biomarker for MOGAD are scarce.

OBJECTIVE

To describe the longitudinal course of sNfL in adult patients with MOGAD in an active as well as a stable disease state in relation to clinical parameters and serum MOG-IgG titers.

METHODS

We conducted a retrospective, exploratory, monocentric cohort study of adult patients with MOGAD. Cohort 1 consisted of five patients in whom NfL was tested as part of their routine clinical workup, all of which had active disease (maximum 6 months since last attack, median 3 months). Cohort 2 comprised 13 patients, which were tested for NfL in the context of a longitudinal study at predefined time intervals, mostly during remission (median 10 months since last attack). sNfL was measured using single molecule array (Simoa) technology at least at two time points (median 3) within a median observation time of 5 months in cohort 1, and at baseline and after a median duration of 12 months in cohort 2. MOG-IgG titers were measured by a fixed cell-based assay.

RESULTS

Change in sNfL correlated positively with change in MOG-IgG titers (rho=0.59, p = 0.027). The variability of sNfL (difference between highest and lowest level) during the observation period was higher in patients who had an attack within six months before baseline (median 37 [interquartile range [IQR] 10-64] pg/ml vs. 2.3 [IQR 1-5] pg/ml, p = 0.006). sNfL increased in patients with an attack during the observation period. Patients with baseline sNfL measurement within two weeks after attack symptom onset displayed relatively low initial sNfL with an increase afterwards.

CONCLUSIONS

Longitudinal sNfL change correlates with MOG-IgG titer change and may be a promising biomarker candidate for disease activity in MOGAD. Increasing sNfL levels might be utilized to adjudicate suspected attacks. In acute attacks, sNfL increase may occur with a delay after symptom onset.

Diagnostic Criteria for Multiple Sclerosis, Neuromyelitis Optica Spectrum Disorders, and Myelin Oligodendrocyte Glycoprotein-immunoglobulin G-associated Disease

The diagnostic workup of multiple sclerosis (MS) has evolved considerably. The 2017 revision of the McDonald criteria shows high sensitivity and accuracy in predicting clinically definite MS in patients with a typical clinically isolated syndrome and allows an earlier MS diagnosis. Neuromyelitis optica spectrum disorders (NMOSD) and myelin oligodendrocyte glycoprotein-immunoglobulin G-associated disease (MOGAD) are recognized as separate conditions from MS, with specific diagnostic criteria. New MR imaging markers may improve diagnostic specificity for these conditions, thus reducing the risk of misdiagnosis. This study summarizes the most recent updates regarding the application of MR imaging for the diagnosis of MS, NMOSD, and MOGAD.

Cognition in patients with myelin oligodendrocyte glycoprotein antibody-associated disease: a prospective, longitudinal, multicentre study of 113 patients (CogniMOG-Study)

BACKGROUND

Data on cognition in patients with myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) are limited to studies with small sample sizes. Therefore, we aimed to analyse the extent, characteristics and the longitudinal course of potential cognitive deficits in patients with MOGAD.

METHODS

The CogniMOG-Study is a prospective, longitudinal and multicentre observational study of 113 patients with MOGAD. Individual cognitive performance was assessed using the Paced Auditory Serial Addition Task (PASAT), the Symbol Digit Modalities Test (SDMT) and the Multiple Sclerosis Inventory Cognition (MuSIC), which are standardised against normative data from healthy controls. Cognitive performance was assessed at baseline and at 1-year and 2-year follow-up assessments. Multiple linear regression was used to analyse demographic and clinical predictors of cognitive deficits identified in previous correlation analyses.

RESULTS

At baseline, the study sample of MOGAD patients showed impaired standardised performance on MuSIC semantic fluency (mean=-0.29, 95% CI (-0.47 to -0.12)) and MuSIC congruent speed (mean=-0.73, 95% CI (-1.23 to -0.23)). Around 1 in 10 patients showed deficits in two or more cognitive measures (11%). No decline in cognition was observed during the 1-year and 2-year follow-up period. Cerebral lesions were found to be negatively predictive for SDMT (B=-8.85, 95% CI (-13.57 to -4.14)) and MuSIC semantic fluency (B=-4.17, 95% CI (-6.10 to -2.25)) test performance.

CONCLUSIONS

Based on these data, we conclude that MOGAD patients show reduced visuomotor processing speed and semantic fluency to the extent that the disease burden includes cerebral lesions.

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

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

Pattern Visually Evoked Potentials (pVEPs) and Retinal Nerve Fiber Thickness in a Japanese Girl With Anti-myelin Oligodendrocyte Glycoprotein Antibody Seropositive Optic Neuritis

We report our findings in a 5-year-old Japanese girl with unilateral optic neuritis who was seropositive for anti-myelin-oligodendrocyte glycoprotein (MOG) antibody. Functional and microstructural changes were assessed longitudinally for 3.5 years by serial recordings of the pattern visual evoked potentials (pVEPs) and optical coherence tomography (OCT) during the acute and chronic phases. On the initial visit, the best-corrected visual acuity (BCVA) in the right eye was light perception. She was treated with 450 mg of intravenous methylprednisolone pulses followed by a gradual tapering of the oral prednisolone. The visual acuity decreased to no light perception, and plasmapheresis combined with high-dose intravenous immunoglobulin therapy was performed. The BCVA quickly improved to 1.0, and no recurrence was detected for approximately four years. The implicit times of N75, P100, and N145 of the pVEPs and peripapillary retinal nerve fiber (pRNFL) thickness in the OCT images were measured during the course of the disease process. The pRNFL thickness of the right eye decreased and was less than one-half of the baseline value at one year and then stabilized. In contrast, the optic pathway function assessed by pVEPs improved. The implicit times of the N75 and P100 components of the right eye were shortened and stabilized at approximately one year. However, the implicit times in the right eye were still longer than that of the left eye. Our findings documented the course of the function and structures of an eye with anti-MOG antibody-positive optic neuritis. This information should be helpful for the understanding of the pathology and prognosis of this disease entity. Further analysis of the pVEPs and structural changes in more cases is needed.

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.

Diagnostic Utility of MOG Antibody Testing in Cerebrospinal Fluid

OBJECTIVE

The aim of this study was to assess the diagnostic utility of cerebrospinal fluid (CSF) myelin oligodendrocyte glycoprotein antibodies (MOG-IgG) testing.

METHODS

We retrospectively identified patients for CSF MOG-IgG testing from January 1, 1996, to May 1, 2023, at Mayo Clinic and other medical centers that sent CSF MOG-IgG for testing including: controls, 282; serum MOG-IgG positive MOG antibody-associated disease (MOGAD), 74; serum MOG-IgG negative high-risk phenotypes, 73; serum false positive MOG-IgG with alternative diagnoses, 18. A live cell-based assay assessed CSF MOG-IgG positivity (IgG-binding-index [IBI], ≥2.5) using multiple anti-human secondary antibodies and end-titers were calculated if sufficient sample volume. Correlation of CSF MOG-IgG IBI and titer was assessed.

RESULTS

The pan-IgG Fc-specific secondary was optimal, yielding CSF MOG-IgG sensitivity of 90% and specificity of 98% (Youden's index 0.88). CSF MOG-IgG was positive in: 4/282 (1.4%) controls; 66/74 (89%) serum MOG-IgG positive MOGAD patients; and 9/73 (12%) serum MOG-IgG negative patients with high-risk phenotypes. Serum negative but CSF positive MOG-IgG accounted for 9/83 (11%) MOGAD patients, and all fulfilled 2023 MOGAD diagnostic criteria. Subgroup analysis of serum MOG-IgG low-positives revealed CSF MOG-IgG positivity more in MOGAD (13/16[81%]) than other diseases with false positive serum MOG-IgG (3/15[20%]) (p = 0.01). CSF MOG-IgG IBI and CSF MOG-IgG titer (both available in 29 samples) were correlated (Spearman's r = 0.64, p < 0.001).

INTERPRETATION

CSF MOG-IgG testing has diagnostic utility in patients with a suspicious phenotype but negative serum MOG-IgG, and those with low positive serum MOG-IgG results and diagnostic uncertainty. These findings support a role for CSF MOG-IgG testing in the appropriate clinical setting. ANN NEUROL 2024;96:34-45.

Validation of the 2023 International Diagnostic Criteria for MOGAD in a Selected Cohort of Adults and Children

BACKGROUND AND OBJECTIVES

To test the performance of the 2023 myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) criteria in adults and children with inflammatory demyelinating conditions who were tested for MOG antibodies (Abs).

METHODS

This was a retrospective study of patients tested for MOG-Abs from 2018 to 2022 in 2 specialist hospitals. The inclusion criteria comprised ≥1 attendance in an adult or pediatric demyelinating disease clinic and complete clinical and MRI records. The final clinical diagnosis of MOGAD, made by the treating neurologist, was taken as the benchmark against which the new criteria were tested. The international MOGAD diagnostic criteria were applied retrospectively; they stipulate at least 1 clinical or MRI supporting feature for MOGAD diagnosis in positive fixed MOG cell-based assay without a titer. The performance MOG-Ab testing alone for MOGAD diagnosis was also assessed and compared with that of MOGAD criteria using the McNemar test.

RESULTS

Of the 1,879 patients tested for MOG-Abs, 539 (135 pediatric and 404 adults) met the inclusion criteria. A clinical diagnosis of MOGAD was made in 86/539 (16%) patients (37 adults, 49 children), with a median follow-up of 3.6 years. The MOGAD diagnostic criteria had sensitivity of 96.5% (adults 91.9%, children 100%), specificity of 98.9% (adults 98.8%, children 98.9%), positive predictive value of 94.3% (adults 89.4%, children 98%), negative predictive value of 99.3% (adults 99.2%, children 100%), and accuracy of 98.5% (adults 98.3%, children 99.2%). When compared with MOG-Ab testing alone, a difference was seen only in adults: a significantly higher specificity (98.9% vs 95.6%, p = 0.0005) and nonstatistically significant lower sensitivity (91.9% vs 100%, p = 0.08).

DISCUSSION

The international MOGAD diagnostic criteria exhibit high performance in selected patients with inflammatory demyelinating diseases (who had a high pretest probability of having MOGAD) compared with best clinical judgment; their performance was better in children than in adults. In adults, the MOGAD criteria led to an improvement in specificity and positive predictive value when compared with MOG-Ab testing alone, suggesting that the requirement of at least 1 clinical or MRI supporting feature is important. Future work should address the generalizability of the diagnostic criteria to cohorts of greater clinical diversity seen within neurologic settings.

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

BACKGROUND

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

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.

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

Background

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

Methods

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

Results

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

Conclusion

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

Emergent Management of Central Nervous System Demyelinating Disorders

OBJECTIVE

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

LATEST DEVELOPMENTS

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

ESSENTIAL POINTS

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

Acute-Onset Blindness in a Patient Diagnosed With Myelin Oligodendrocyte Glycoprotein Antibody Disease (MOG-AD): A Case Report

Myelin oligodendrocyte glycoprotein antibody disease (MOG-AD) poses a diagnostic challenge, often masquerading as other neurological disorders such as multiple sclerosis and aquaporin-4-positive neuromyelitis optica spectrum disorder. The deceptive clinical similarities demand a nuanced approach to differentiate these conditions effectively. This entails an extensive evaluation encompassing a meticulous medical history, advanced magnetic resonance imaging (MRI), cerebrospinal fluid analysis, and serum studies. In this context, we present a compelling case involving a 28-year-old Hispanic female with a history of migraine headache. She sought medical attention due to acute peripheral vision loss, ultimately diagnosed as MOG-AD through a comprehensive clinical assessment coupled with specific diagnostic tests. This case underscores the critical importance of precision in diagnostic procedures to ensure accurate identification and subsequent tailored treatment for MOG-AD, avoiding potential pitfalls associated with its resemblance to other neurological disorders.

Low T3 syndrome is associated with the severity of myelin oligodendrocyte glycoprotein antibody-associated disease exacerbation

Background

Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is a rare autoimmune inflammatory disease of the central nervous system, (CNS) different from multiple sclerosis (MS) and neuromyelitis optica spectrum disorder (NMOSD). While numerous studies have delved into the involvement of thyroid antibodies (ATAbs) and thyroid function in NMOSD and MS. The objective of this study is to explore the clinical significance of thyroid dysfunction and ATAbs abnormalities in adult patients with MOGAD.

Methods

36 adult inpatients diagnosed with MOGAD and 47 sex- and age-matched healthy controls were enrolled. Patients were divided into two groups based on the presence or absence of low T3 syndrome. Demographics, clinical characteristics, and results of auxiliary examinations were compared across the subgroups. Moreover, an analysis was conducted to explore the correlations between thyroid hormone levels and Expanded Disability Status Scale (EDSS) scores.

Results

Thyroid dysfunction was notably more frequent in MOGAD patients than healthy controls (p < 0.0001), particularly low T3 syndrome (p=0.03). Furthermore, subgroup analyses revealed that the low T3 syndrome group exhibited higher EDSS scores and a higher proportion of individuals with EDSS scores > 3, in comparison to the non-low T3 syndrome group (p = 0.014, p = 0.046). However, no significant differences were observed in demographic characteristics, annual relapse rates, clinical phenotypes, laboratory and MRI results, and EEG abnormalities between the two groups. Additional Spearman's analysis showed significantly negative correlations between the TT3 and FT3 levels with EDSS scores (r = -0.367, p = 0.028; r = -0.377, p = 0.024). Typical brain lesions and paralateral ventricle lesions were significantly rare in patients with positive ATAbs compared to those with negative ATAbs (p = 0.0001, p = 0.03), although the incidence of ATAbs abnormalities did not differ significantly between MOGAD patients and healthy controls.

Conclusions

Overall, this study confirmed thyroid dysfunction, especially low T3 syndrome, is frequent in adult MOGAD patients. Patients with low T3 syndrome exhibited elevated EDSS scores and a significantly higher incidence of unfavorable condition. additionally, the correlation analysis model manifests that FT3 and TT3 levels were negatively correlated with EDSS scores. These evidences indicate that low T3 syndrome is associated with the severity of MOGAD exacerbation.

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

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

Structural changes in spinal cord following optic neuritis: Insights from quantitative spinal MRI

OBJECTIVES

Previous studies have demonstrated that optic neuritis (ON) affects brain plasticity. However, whether ON affects the spinal cord remains unclear. We aimed to investigate the spinal cord changes in ON and their associations with disability.

METHODS

A total of 101 ON patients, and 41 healthy controls (HC) were retrospectively recruited. High-resolution imaging was conducted using a Magnetization Prepared Rapid Acquisition Gradient-Echo (MP-RAGE) sequence for T1-weighted images and an echo planar imaging (EPI) sequence for Diffusion Tensor Imaging (DTI) data collection. Additionally, patients' disability and cognitive impairment were evaluated using the Expanded Disability Status Scale (EDSS) and the Paced Auditory Serial Addition Test (PASAT), respectively. The quantitative spinal MRI was employed to examine the cross-sectional area (CSA) and diffusion indicators, with a specific focus on calculating the average values across the C2-C7 cervical spinal cord segments. CSA, fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD) were compared between groups. Correlation analyses were performed between CSA, diffusion indicators, and clinical variables.

RESULTS

No significant differences were found in CSA between ON patients and HCs. MD (p = 0.007) and RD (p = 0.018) were increased in ON patients compared with HCs, and AD was decreased in ON (p = 0.013). The AD values of the ON patients were significantly positively correlated with PASAT scores (r = 0.37, p < 0.001).

CONCLUSIONS

This study provided imaging evidence for DTI abnormalities in patients with ON. Spinal cord DTI can improve our knowledge of the path physiology of ON, and clinical progression.

Decreased serum tryptophan levels in patients with MOGAD:a cross-sectional survey

BACKGROUND

Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is an inflammatory demyelinating disorder of central nervous system (CNS). Tryptophan indole catabolites have been reported to associate with the inflammatory diseases of the CNS. However, the roles of tryptophan indole catabolites have been rarely elucidated in MOGAD.

METHODS

This cross-sectional study enrolled forty MOGAD patients, twenty patients with other non-inflammatory neurological diseases (OND) and thirty-five healthy participants. Serum and cerebrospinal fluid (CSF) samples of MOGAD and OND subjects during clinical attacks, serum samples of healthy participants were obtained. The concentrations of tryptophan, indoleacetic acid (IAA), indoleacrylic acid (IA) and indole-3-carboxylic acid (I-3-CA) were measured using high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). The correlations between tryptophan indole catabolites and maintenance immunotherapy, disease duration, overall numbers of attacks, short-term outcome in MOGAD patients were investigated.

RESULTS

Levels of serum tryptophan, IAA, IA and CSF tryptophan in MOGAD patients were significantly decreased, while levels of serum I-3-CA and CSF IA were markedly increased compared with OND patients and healthy controls. Levels of serum tryptophan, CSF tryptophan and IA were significantly decreased in MOGAD patients who had received maintenance immunotherapy within 6 months before the attack. In MOGAD patients, serum and CSF tryptophan conversely correlated with disease duration and overall numbers of attacks, and serum IA negatively correlated with disease duration. Furthermore, serum tryptophan in MOGAD patients negatively correlated with the modified Rankin Scale (mRS) scores at 3 months.

CONCLUSION

This study manifested decreased serum tryptophan levels and serum tryptophan may be the potential marker to predict the short-term outcome in MOGAD patients.

Epidemiology and Healthcare Utilization in Pediatric Multiple Sclerosis and Neuromyelitis Optica: A Nationwide Population-Based Study in South Korea (2016-2020)

Pediatric multiple sclerosis (MS) and neuromyelitis optica (NMO) are rare acquired demyelinating syndrome with limited epidemiological data available, particularly in non-Western setting. This study aimed to demonstrate the epidemiology of pediatric MS and NMO in South Korea and to analyze of healthcare utilization and economic burden associated with these conditions. Using a nationwide population-based database from the Korean Health Insurance Review and Assessment Service database, we identified pediatric cases (age < 20 years) of MS and NMO from 2016 to 2020. We analyzed incidence, prevalence, healthcare utilization and medical costs. The study found low age-standardized incidence and prevalence rates for pediatric MS and NMO in South Korea. There was a marked disparity in healthcare utilization between urban and rural areas. Most healthcare interactions occurred in tertiary hospitals in urban settings, particularly in Seoul. The study also highlighted the substantial economic burden associated with the management of rare diseases, with annual variability in medical costs. Pediatric MS and NMO are extremely rare in South Korea, with significant regional disparity in healthcare utilization. The findings emphasize the need for targeted healthcare policies to improve access and reduce disparities, particularly for chronic and rare diseases requiring specialized care.

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

RATIONALE AND OBJECTIVES

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

MATERIALS AND METHODS

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

RESULTS

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

CONCLUSION

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