The long-term outcome of MOGAD: An observational national cohort study of 61 patients

Clinico-investigational profile, relapse predictors and outcomes of pediatric patients with anti-myelin oligodendrocyte associated disorders: An experience from tertiary centre

BACKGROUND

The data on relapse and outcome predictors in pediatric anti-Myelin oligodendrocyte antibody associated diseases (MOGAD) is poorly delineated in the literature.

METHODS

We performed a retrospective study of the clinico-investigational profile of pediatric patients (age<18 years) who met the international diagnostic criteria for MOGAD, 2023 and assessed the predictors for clinical relapse and equated the trajectory of outcomes over a long-term follow-up.

RESULTS

We recruited 46 children (males=24, 52.2 %), with a median age at onset 11(8 to 16) years and a median duration of 15 (IQR 6-45) days. The core demyelinating events observed were optic neuritis (n = 19, 41.3 %), acute disseminating encephalomyelitis (n = 13, 28.3 %), transverse myelitis (n = 10, 21.7 %), cerebral deficits (n = 3, 6.5 %), brainstem/cerebellar syndrome (n = 2, 4.3 %), cerebral cortical encephalitis (n = 2, 4.3 %) and atypical presentations (n = 1, 2.2 %). Prevalence of ADEM was significantly higher among children <10 years (p = 0.046). At a median follow-up of 28 months, ON was significantly associated with relapse, with an odds ratio (OR) of 5.175 (95 % CI 1.286-20.824, p = 0.021), unlike other core demyelinating events. In 11 cases (23.9 %) referral diagnosis was not MOGAD. Neither the degree of serum anti-MOG antibody positivity [strong vs weak: OR 1.506 (0.407 to 5.578), p = 0.480] nor its persistence [OR 0.955 (0.201 to 4.538), p = 0.953] were identified to be relapse predictors. There was a significant improvement in modified Rankin scale (mRS) scores between presentation, intermediate and at last follow-up (p < 0.001).

CONCLUSIONS

The study highlights the predictors for relapse, and presents a follow-up data of >2 years on pediatric MOGAD. It reveals optic neuritis as a risk factor for relapse. The study emphasises the importance of a broad range of antibody testing including anti-MOG in patients with suspected autoimmune encephalitis.

Outcomes of immunosuppressive therapy discontinuation in patients with myelin oligodendrocyte glycoprotein antibody-associated disease

BACKGROUND

Research on the optimal duration of immunosuppressive therapy (IST) and the outcome upon its discontinuation in myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) remains limited.

OBJECTIVE

To evaluate the outcomes following IST discontinuation in MOGAD.

METHODS

This multicenter retrospective study collected data from 333 MOGAD patients in Korea. Among 273 patients who received IST, 41 who discontinued IST were analyzed.

RESULTS

The median age at disease onset was 38.3 years (interquartile range (IQR), 27.6-53.1). Before IST withdrawal, 21 (51%) patients exhibited relapsing courses. Over a median follow-up of 23.5 months (IQR, 12.1-39.5) after discontinuation, 10 patients (24.4%) relapsed after a median of 8.2 months (IQR, 6.3-11.5). All relapses occurred in patients with a prior relapsing course (10/21, 47.6%); none with prior monophasic courses relapsed. Among 21 prior relapsing patients, relapse after discontinuation group had a shorter IST duration than non-relapse group (median, 9.4 vs 50.9 months, p = 0.036). None of the 41 patients had severe disability (Expanded Disability Status Scale (EDSS) score ⩾ 4.0 or Visual Functional System score ⩾ 5) at the last visit.

CONCLUSION

IST discontinuation did not necessarily lead to relapse and could be considered with an individualized approach based on factors such as disease course and IST duration.

Longitudinal assessment of cognitive function in patients with non-relapsing MOG-IgG associated disease

BACKGROUND

Non-relapsing myelin oligodendrocyte glycoprotein antibody-associated disease (nr-MOGAD) is an inflammatory demyelinating disorder of the central nervous system that frequently affects younger populations. The longitudinal impact of nr-MOGAD on cognitive function remains poorly characterized.

OBJECTIVES

To investigate cognitive profiles and longitudinal cognitive changes in patients with nr-MOGAD compared to individuals with Relapsing-Remitting Multiple Sclerosis (pwRRMS) and healthy controls (HCs).

METHODS

A cohort of 8 nr-MOGAD patients, 32 pwRRMS patients, and 22 HCs underwent a baseline and a 12-month follow-up assessment with the Brief Repeatable Battery of Neuropsychological Tests (BRBN) and Stroop test.

RESULTS

At baseline, nr-MOGAD patients exhibited moderate cognitive deficits, particularly in verbal memory and processing speed domains, with scores intermediate between pwRRMS and HCs. At follow-up, nr-MOGAD patients, especially those with pediatric-onset, showed significant cognitive recovery, contrasting with the stable impairments observed in pwRRMS.

CONCLUSIONS

Cognitive impairment patterns in nr-MOGAD are distinct from those observed in pwRRMS and, particularly in younger patients, show a frequent reversal unlike pwRRMS, in which persistently impaired cognitive performances are much more common.

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

BACKGROUND

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSION

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

MOG antibody-associated disease epidemiology in Olmsted County, USA, and Martinique

OBJECTIVES

To report myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) epidemiology in two American regions using 2023 diagnostic criteria.

PATIENTS AND METHODS

We compared age- and sex-adjusted incidence and prevalence of MOGAD per 2023 diagnostic criteria in Olmsted County (Minnesota [USA]) and Martinique (Caribbean [FR]) (01/01/2003-12/31/2018, prevalence day) using Poisson regression. Archived sera in 68-85% were available for MOG-IgG testing by live cell-based assay at Mayo Clinic.

RESULTS

Of 21 patients with MOG-IgG positivity identified, 16 fulfilled MOGAD criteria (38% female; median age of 27 years, interquartile-range [IQR 23-42]) and five with low-positive MOG-IgG did not (optic neuritis lacking supportive criteria, 2; alternative diagnosis of multiple sclerosis, 3). MOGAD prevalence was similar in Olmsted County (3.70/100,000, 95% confidence interval [CI] 0.74-6.66]) and Martinique (2.61/100,000; 95% CI 0.85-4.37, P = 0.46). MOGAD incidence was 3.00/million-person-years (95% CI 0.78-5.22) in Olmsted County and 1.18/million-person-years (95% CI 0.30-2.07) in Martinique (P = 0.08). Children represented 29% of MOGAD in Olmsted County and 11% in Martinique. During their disease course the attacks included: optic neuritis (13/16 [81%]); myelitis (6/16 [38%]); and acute disseminated encephalomyelitis (2/16 [13%]). The proportion of MOGAD among incident CNS demyelinating diseases was greater in children (13-14%) than adults (2-4%; P = 0.005). At last follow-up (median, 5 years, IQR 2-9), the median EDSS was 1.0 (IQR 0.5-2.75) with 1/16 (6%) blind in one eye and 9/16 (56%) had relapsing MOGAD.

CONCLUSIONS

This study provides estimates of incidence and prevalence of MOGAD in the USA and Martinique and shows that, although children are predisposed, the disease is spread broadly across the age spectrum and population-based outcomes are favorable.

Ofatumumab successfully treats myelin oligodendrocyte glycoprotein antibody-associated disease accompanied by Epstein-Barr viral infection: a case series

Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) caused by pathogenic immunoglobulin G antibodies to myelin oligodendrocyte glycoprotein is a rare demyelinating disease of the central nerve system (CNS). The clinical phenotypes of MOGAD include acute disseminated encephalomyelitis, optic neuritis, and transverse myelitis. At present, the mechanism underlying the disease is unknown. Herein, we report two cases of MOGAD accompanied by Epstein-Barr virus (EBV) infection. Both presented inflammation response in the cerebrospinal fluid (CSF), demonstrating elevated level of cell accounts and protein. EBV genomic sequence was also detected in the CSF samples. The patients recovered substantially after 3 months following a combination treatment with methylprednisolone and immunosuppressive therapy with ofatumumab. These cases provide new insight into the production of MOG-IgG and the possible pathological mechanisms underlying MOGAD. The cases also confirm the association with EBV, a virus that infects human B cells and has been proposed to be a trigger for MOGAD. This is the first report on subcutaneous ofatumumab treatment for MOGAD triggered by EBV, suggesting that this is a potentially valuable therapeutic option.

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

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

Efficacy of tocilizumab in highly relapsing MOGAD with an inadequate response to intravenous immunoglobulin therapy: A case series

BACKGROUND

Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is an inflammatory disease affecting the central nervous system that may require long-term immunotherapy in relapsing cases. While immunotherapies utilized in neuromyelitis optica spectrum disorder have shown varying efficacy in MOGAD, intravenous immunoglobulin G (IVIG) recently emerged as a promising treatment. Tocilizumab, a monoclonal antibody that targets the interleukin-6 (IL-6) receptor, has been reported to be effective in refractory MOGAD in several case studies, where tocilizumab was introduced primarily due to rituximab failure.

METHODS

This retrospective study was conducted in a single center and focused on MOGAD patients receiving tocilizumab therapy, who have shown limited response to various immunotherapies, including intravenous immunoglobulin G (IVIG) maintenance.

RESULTS

This study included four patients, three adults, and one child. They experienced a median of 9 attacks (range 6-9) throughout their disease course despite at least two immunotherapies. All patients transitioned to tocilizumab after experiencing a median of two relapses (range 1-3) while on IVIG maintenance for a median of 21.9 months (range 21.3-49.6 months). Following the monthly tocilizumab administration at a dose of 8g/kg, all patients remained relapse-free with a median follow-up duration of 25.0 months (range 9.8-51.3 months) without reported adverse events.

CONCLUSION

Targeting the IL-6 pathway appears to offer therapeutic benefits in highly relapsing MOGAD patients who poorly respond to IVIG maintenance therapy.

Prognostic factors associated with disability in a cohort of neuromyelitis optica spectrum disorder and MOG-associated disease from a nationwide Portuguese registry

INTRODUCTION

Neuromyelitis optica spectrum disorders (NMOSD) and MOG-associated disease (MOGAD) are an increasingly recognized group of demyelinating disorders of the central nervous system. Previous studies suggest that prognosis is predicted by older age at onset, number of relapses, the severity of the first attack and autoantibody status.

OBJECTIVE

To study prognostic factors associated with disability progression and additional relapses in the 3-year follow-up of a national NMOSD/MOGAD cohort.

RESULTS

Out of 180 of the initial Portuguese cohort, data on 82 patients was available at the end of the follow-up period (2019-2022). Two patients died. Twenty (24.4%) patients had one or more attack in this period (25 attacks in total), mostly transverse myelitis (TM) (56.0%) or optic neuritis (32.0%). MOGAD was significantly associated with a monophasic disease course (p = 0.03), with milder attacks (p = 0.01), while AQP4 + NMOSD was associated with relapses (p = 0.03). The most common treatment modalities were azathioprine (38.8%) and rituximab (18.8%). AQP4 + NMOSD more frequently required chronic immunosuppressive treatment, particularly rituximab (p = 0.01). Eighteen (22.5%) had an EDSS ≥6 at the end of the follow-up. AQP4 + NMOSD (p < 0.01) and the occurrence of transverse myelitis (TM) during disease (p = 0.04) correlated with an EDSS≥6 at the end of the follow-up period. MOGAD was significantly associated with an EDSS<6 (p < 0.01), and MOG+ cases that reached an EDSS>6 were significantly older (64.0 ± 2.8 versus 31.0 ± 17.1, p = 0.017). A bivariate logistic regression model including the serostatus and TM attacks during disease history successfully predicted 72.2% of patients that progressed to an EDSS≥6.

CONCLUSION

This study highlights that myelitis predict increased disability (EDSS≥6) in NMOSD/MOGAG and AQP4 positivity is associated with increased disability.

Early Maintenance Treatment Initiation and Relapse Risk Mitigation After a First Event of MOGAD in Adults: The MOGADOR2 Study

BACKGROUND AND OBJECTIVES

Because myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is a recently identified autoimmune disorder, the natural history of MOGAD is still not well described. The objective of this study was to describe the long-term outcomes of adult patients with MOGAD. In addition, we aimed to identify factors affecting relapse risk and neurologic outcomes.

METHODS

Clinical and biological data were obtained from patients with a first event of MOGAD and included in the French nationwide incident cohort between February 2014 and March 2017. Only patients aged 18 years or older at disease onset and with observation period of at least 3 months were included. Data were collected prospectively until July 2023 and registered in the dedicated French nationwide database. This form includes every relapse with phenotype description during follow-up, date of last assessment, final clinical outcome with Expanded Disability Status Scale score and visual acuity, and maintenance therapy. The probability of recurrence-free survival was assessed using the Kaplan-Meier method.

RESULTS

We included 128 patients. The onset phenotype was isolated optic neuritis in 81 patients (63.3%) and isolated myelitis in 25 patients (19.5%). The median follow-up duration was 77.8 months (range 3.2-111.2), with 49 patients (38.3%) experienced at least one relapse. Median times from onset to second and third attacks were 3.2 (1.0-86.2) and 13.0 (2.6-64.4) months, respectively. At the last assessment, Expanded Disability Status Scale Score was ≥3 and ≥6 in 22 (17.2%) and 6 (4.7%) patients, respectively. Eighty patients received at least one maintenance treatment. This treatment was initiated after the first attack in 47 patients (36.7% of the whole cohort) and at the time of a second attack in 25 (19.5%). Multivariate analysis revealed that initiating maintenance treatment after the first attack was associated with a lower relapse risk (OR = 0.26 [95% CI 0.11-0.62], p = 0.002). In patients receiving maintenance therapy after first attack, the 2-year, 4-year, 6-year, and 8-year relapse risks were 11%, 15%, 20%, and 20%, respectively. In other patients, the risks were 41%, 46%, 51%, and 56%.

DISCUSSION

The highest risk of a relapse in MOGAD occurs early, and initiating maintenance therapy from the first attack substantially reduced the relapse risk.

CLASSIFICATION OF EVIDENCE

This study provides Class III evidence that initiating maintenance therapy from the first attack in patients with MOGAD reduces the relapse risk.

Unravelling the Complexity of Myelin Oligodendrocyte Glycoprotein Antibody-Associated Disease

Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is a rare autoimmune disorder characterized by recurrent episodes of demyelination affecting the central nervous system. The following case report showcases a thorough analysis of a 21-year-old female patient presenting with MOGAD, outlining her clinical presentation, diagnostic workup, treatment protocol, and long-term management outcomes. Through a multidisciplinary approach, we aim to augment the understanding of this complex neurological entity and steer optimal therapeutic interventions.

Cognitive and psychopathological features of neuromyelitis optica spectrum disorder and myelin oligodendrocyte glycoprotein antibody-associated disease: A narrative review

Clinicians are becoming increasingly aware of the cognitive and psychopathological consequences of neurological diseases, which were once thought to manifest with motor and sensory impairments only. The cognitive profile of multiple sclerosis, in particular, is now well-characterised. Similar efforts are being made to better characterise the cognitive profile of other central nervous system inflammatory demyelinating autoimmune disorders. This review discusses the current understanding of the cognitive and psychological features of neuromyelitis optica spectrum disorder (NMOSD) and myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD). Detailed analysis of the cognitive sequelae of the above conditions can not only assist with understanding disease pathogenesis but also can guide appropriate management of the symptoms and consequently, improve the quality of life and long-term outcomes for these patients. This narrative review will also identify research gaps and provide recommendations for future directions in the field.

An aggressive form of MOGAD treated with aHSCT: A case report

BACKGROUND

Although myelin-oligodendrocyte-glycoprotein (MOG)-antibody-associated disease (MOGAD) has been considered a more favorable demyelinating central nervous system disorder, recent data evidence that some patients might experience severe relapses and high disability. Actual treatment-options are acquired mostly from anti-aquaporin-4-antibody-positive neuromyelitis optica spectrum disorder and rely on clinical experience. Therefore, treatment of aggressive forms of MOGAD can be challenging.

OBJECTIVES AND METHODS

To describe a patient with an aggressive MOGAD treated with autologous hematopoietic stem cell transplantation (aHSCT).

RESULTS

A 56-year-old man was diagnosed with MOGAD in 2017 because of right optic-neuritis and anti-MOG-antibody positivity. In the following 2 years, he experienced two optic neuritis with good recovery after high-dose steroid. At the end of 2019, he presented sensory and motor impairment at lower limbs with evidence of several spinal, longitudinally extended, tumefactive inflammatory lesions. Despite sequential treatment with rituximab and tocilizumab alongside high-dose steroid, intravenous immunoglobulins and plasma-exchange, he experienced several clinical relapses and exhibited persistent magnetic resonance activity. He was finally addressed to intense immunosuppression with myeloablative conditioning regimen followed by autologous hematopoietic stem cell transplantation (aHSCT). After 2 years follow-up, he is free from disease-activity.

CONCLUSIONS

In a patient affected by aggressive, treatment-refractory MOGAD, aHSCT resulted as safe and was able to suppress disease-activity for over 2 years.

Differentiated pattern of complement system activation between MOG-IgG-associated disease and AQP4-IgG-positive neuromyelitis optica spectrum disorder

Background

Myelin oligodendrocyte glycoprotein antibody (MOG) immunoglobulin G (IgG)-associated disease (MOGAD) has clinical and pathophysiological features that are similar to but distinct from those of aquaporin-4 antibody (AQP4-IgG)-positive neuromyelitis optica spectrum disorders (AQP4-NMOSD). MOG-IgG and AQP4-IgG, mostly of the IgG1 subtype, can both activate the complement system. Therefore, we investigated whether the levels of serum complement components, regulators, and activation products differ between MOGAD and AQP4-NMOSD, and if complement analytes can be utilized to differentiate between these diseases.

Methods

The sera of patients with MOGAD (from during an attack and remission; N=19 and N=9, respectively) and AQP4-NMOSD (N=35 and N=17), and healthy controls (N=38) were analyzed for C1q-binding circulating immune complex (CIC-C1q), C1 inhibitor (C1-INH), factor H (FH), C3, iC3b, and soluble terminal complement complex (sC5b-9).

Results

In attack samples, the levels of C1-INH, FH, and iC3b were higher in the MOGAD group than in the NMOSD group (all, p<0.001), while the level of sC5b-9 was increased only in the NMOSD group. In MOGAD, there were no differences in the concentrations of complement analytes based on disease status. However, within AQP4-NMOSD, remission samples indicated a higher C1-INH level than attack samples (p=0.003). Notably, AQP4-NMOSD patients on medications during attack showed lower levels of iC3b (p<0.001) and higher levels of C3 (p=0.008), C1-INH (p=0.004), and sC5b-9 (p<0.001) compared to those not on medication. Among patients not on medication at the time of attack sampling, serum MOG-IgG cell-based assay (CBA) score had a positive correlation with iC3b and C1-INH levels (rho=0.764 and p=0.010, and rho=0.629 and p=0.049, respectively), and AQP4-IgG CBA score had a positive correlation with C1-INH level (rho=0.836, p=0.003).

Conclusions

This study indicates a higher prominence of complement pathway activation and subsequent C3 degradation in MOGAD compared to AQP4-NMOSD. On the other hand, the production of terminal complement complexes (TCC) was found to be more substantial in AQP4-NMOSD than in MOGAD. These findings suggest a strong regulation of the complement system, implying its potential involvement in the pathogenesis of MOGAD through mechanisms that extend beyond TCC formation.

Delimiting MOGAD as a disease entity using translational imaging

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

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

BACKGROUND

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

METHOD

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

RESULTS

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

CONCLUSIONS

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

Defining the natural history of tumefactive demyelination: A retrospective cohort of 257 patients

OBJECTIVE

To describe demographic, clinical, and radiographic features of tumefactive demyelination (TD) and identify factors associated with severe attacks and poor outcomes.

METHODS

Retrospective review of TD cases seen at Mayo Clinic, 1990-2021.

RESULTS

Of 257 patients with TD, 183/257 (71%) fulfilled the 2017 multiple sclerosis (MS) McDonald criteria at the last follow-up, 12/257 (5%) had myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD), 0 had aquaporin-4-IgG seropositive neuromyelitis optic spectrum disorders (AQP4+ NMOSD), and 62/257 (24%) were cryptogenic. Onset before age 18 was present in 18/257 (7%). Female to male ratio was 1.3:1. Cerebrospinal fluid oligoclonal (CSF) bands were present in 95/153 (62%). TD was the first demyelinating attack in 176/257 (69%). At presentation, 59/126 (47%) fulfilled Barkhof criteria for dissemination in space, 59/100 (59%) had apparent diffusion coefficient (ADC) restriction, and 57/126 (45%) had mass effect. Despite aggressive clinical presentation at onset, 181/257 (70%) of patients remained fully ambulatory (Expanded Disability Status Scale [EDSS] ≤4) after a 3.0-year median follow-up duration. Severe initial attack-related disability (EDSS ≥4) was more common in patients with motor symptoms (81/143 vs. 35/106, p < 0.0001), encephalopathy (20/143 vs. 2/106, p < 0.0001) and ADC restriction on initial MRI (42/63 vs. 15/33, p = 0.04). Poor long-term outcome (EDSS ≥4) was more common in patients with older onset age (41.9 ± 15 vs. 36.8 ± 15.6, p = 0.02) and motor symptoms at onset (49/76 vs. 66/171, p < 0.0001).

INTERPRETATION

Most TD patients should be considered part of the MS spectrum after excluding MOGAD and NMOSD. Motor symptoms and older age at presentation portend a poor outcome.

Do Early Relapses Predict the Risk of Long-Term Relapsing Disease in an Adult and Paediatric Cohort with MOGAD?

OBJECTIVE

Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) can be monophasic or relapsing, with early relapse being a feature. However, the relevance of early relapse on longer-term relapse risk is unknown. Here, we investigate whether early relapses increase longer-term relapse risk in patients with MOGAD.

METHODS

A retrospective analysis of 289 adult- and pediatric-onset patients with MOGAD followed for at least 2 years in 6 specialized referral centers. "Early relapses" were defined as attacks within the first 12 months from onset, with "very early relapses" defined within 30 to 90 days from onset and "delayed early relapses" defined within 90 to 365 days. "Long-term relapses" were defined as relapses beyond 12 months. Cox regression modeling and Kaplan-Meier survival analysis were used to estimate the long-term relapse risk and rate.

RESULTS

Sixty-seven patients (23.2%) had early relapses with a median number of 1 event. Univariate analysis revealed an elevated risk for long-term relapses if any "early relapses" were present (hazard ratio [HR] = 2.11, p < 0.001), whether occurring during the first 3 months (HR = 2.70, p < 0.001) or the remaining 9 months (HR = 1.88, p = 0.001), with similar results yielded in the multivariate analysis. In children with onset below aged 12 years, only delayed early relapses were associated with an increased risk of long-term relapses (HR = 2.64, p = 0.026).

INTERPRETATION

The presence of very early relapses and delayed early relapses within 12 months of onset in patients with MOGAD increases the risk of long-term relapsing disease, whereas a relapse within 90 days appears not to indicate a chronic inflammatory process in young pediatric-onset disease. ANN NEUROL 2023;94:508-517.

Pediatric myelin oligodendrocyte glycoprotein antibody-associated disease in southern China: analysis of 93 cases

Objective

To study the clinical features of children diagnosed with myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) in southern China.

Methods

Clinical data of children diagnosed with MOGAD from April 2014 to September 2021 were analyzed.

Results

A total of 93 children (M/F=45/48; median onset age=6.0 y) with MOGAD were involved. Seizures or limb paralysis was the most common onset or course symptom, respectively. The most common lesion locations in brain MRI, orbital MRI, and spinal cord MRI were basal ganglia and subcortical white matter, the orbital segment of the optic nerve, and the cervical segment, respectively. ADEM (58.10%) was the most common clinical phenotype. The relapse rate was 24.7%. Compared with the patients without relapse, relapsed patients had a longer interval from onset to diagnosis (median: 19 days VS 20 days) and higher MOG antibody titer at onset (median: 1:32 VS 1:100) with longer positively persistent (median: 3 months VS 24 months). All patients received IVMP plus IVIG at the acute phase, and 96.8% of patients achieved remission after one to three courses of treatment. MMF, monthly IVIG, and maintaining a low dose of oral prednisone were used alone or in combination as maintenance immunotherapy for relapsed patients and effectively reduced relapse. It transpired 41.9% of patients had neurological sequelae, with movement disorder being the most common. Compared with patients without sequelae, patients with sequelae had higher MOG antibody titer at onset (median: 1:32 VS 1:100) with longer persistence (median: 3 months VS 6 months) and higher disease relapse rate (14.8% VS 38.5%).

Conclusions

Results showed the following about pediatric MOGAD in southern China: the median onset age was 6.0 years, with no obvious sex distribution difference; seizure or limb paralysis, respectively, are the most common onset or course symptom; the lesions of basal ganglia, subcortical white matter, the orbital segment of the optic nerve, and cervical segment were commonly involved in the CNS MRI; ADEM was the most common clinical phenotype; most had a good response to immunotherapy; although the relapse rate was relatively high, MMF, monthly IVIG and a low dose of oral prednisone might effectively reduce relapse; neurological sequelae were common, and possibly associated with MOG antibody status and disease relapse.

Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD): current understanding and challenges

New diagnostic criteria for myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) have recently been proposed, distinguishing this syndrome from other inflammatory diseases of the central nervous system. Seropositivity status for MOG-IgG autoantibodies is important for diagnosing MOGAD, but only in the context of robust clinical characterization and cautious interpretation of neuroimaging. Over the last several years, access to cell-based assay (CBA) techniques has improved diagnostic accuracy, yet the positive predictive value of serum MOG-IgG values varies with the prevalence of MOGAD in any given patient population. For this reason, possible alternative diagnoses need to be considered, and low MOG-IgG titers need to be carefully weighted. In this review, cardinal clinical features of MOGAD are discussed. Key challenges to the current understanding of MOGAD are also highlighted, including uncertainty regarding the specificity and pathogenicity of MOG autoantibodies, the need to identify immunopathologic targets for future therapies, the quest to validate biomarkers that facilitate diagnosis and detect disease activity, and the importance of deciphering which patients with MOGAD require long-term immunotherapy.

Low mortality rate in a large cohort of myelin oligodendrocyte glycoprotein antibody disease (MOGAD)

The mortality rates of individuals with myelin oligodendrocyte glycoprotein antibody disease (MOGAD) are currently unknown. This study aimed to assess the mortality rate in a large cohort of patients with MOGAD. Since none of the patients in our cohort died, we estimated the upper limit of a 95% confidence interval of the crude mortality rate in the cohort to be 2.1%. These data suggest that mortality in MOGAD is lower than that reported in other neuroinflammatory diseases and comparable to the age-adjusted mortality rates of the general population in the United States. Additional studies are warranted to confirm this observation.

Clinical outcomes and prognostic factors in patients with optic neuritis related to NMOSD and MOGAD in distinct ethnic groups from Latin America

BACKGROUND

Optic neuritis (ON) can be an initial manifestation of neuromyelitis optica spectrum disorder (NMOSD) associated with aquaporin 4-antibody (AQP4-Ab) or myelin oligodendrocyte glycoprotein antibody (MOG-Ab)-associated disease (MOGAD). Additionally, both diseases may have overlapping paraclinical and radiological features. These diseases may have different outcomes and prognoses. We aimed to compare clinical outcomes and prognostic features of patients with NMOSD and MOGAD presenting ON as first attack, from different ethnic groups in Latin America.

METHODS

We conducted a retrospective observational multicenter study in patients from Argentina (n = 61), Chile (n = 18), Ecuador (n = 27), Brazil (n = 30), Venezuela (n = 10) and Mexico (n = 49) with MOGAD or NMOSD related ON. Predictors of disability outcomes at last follow-up, namely visual disability (Visual Functional System Score ≥4), motor disability (permanent inability to walk further than 100 m unaided) and wheelchair dependence based on EDSS score were evaluated.

RESULTS

After a mean disease duration of 42.7 (±40.2) months in NMOSD and 19.7 (±23.6) in MOGAD, 55% and 22% (p>0.001) experienced permanent severe visual disability (visual acuity from 20/100 to 20/200), 22% and 6% (p = 0.01) permanent motor disability and 11% and 0% (p = 0.04) had become wheelchair dependent, respectively. Older age at disease onset was a predictor of severe visual disability (OR=1,03 CI95%1.01-1.05, p = 0.03); older age at disease onset (OR=1,04 CI95%1.01-1.07, p = 0.01), higher number of relapses (OR=1,32 CI95%1.02-1.71, p = 0.03) and rituximab treatment (OR=0,36 CI95%0.14-0.90, p = 0.02) were predictors of permanent motor disability, whereas ON associated with myelitis at disease onset was a predictor of wheelchair dependency (OR=4,16, CI95%1.23-14.08, p = 0,02) in NMOSD patients. No differences were found when evaluating distinct ethnic groups (Mixed vs. Caucasian vs. Afro-descendant) CONCLUSIONS: NMOSD was associated with poorer clinical outcomes than MOGAD. Ethnicity was not associated with prognostic factors. Distinct predictors of permanent visual and motor disability and wheelchair dependency in NMOSD patients were found.

Diagnosis of myelin oligodendrocyte glycoprotein antibody-associated disease: International MOGAD Panel proposed criteria

Serum antibodies directed against myelin oligodendrocyte glycoprotein (MOG) are found in patients with acquired CNS demyelinating syndromes that are distinct from multiple sclerosis and aquaporin-4-seropositive neuromyelitis optica spectrum disorder. Based on an extensive literature review and a structured consensus process, we propose diagnostic criteria for MOG antibody-associated disease (MOGAD) in which the presence of MOG-IgG is a core criterion. According to our proposed criteria, MOGAD is typically associated with acute disseminated encephalomyelitis, optic neuritis, or transverse myelitis, and is less commonly associated with cerebral cortical encephalitis, brainstem presentations, or cerebellar presentations. MOGAD can present as either a monophasic or relapsing disease course, and MOG-IgG cell-based assays are important for diagnostic accuracy. Diagnoses such as multiple sclerosis need to be excluded, but not all patients with multiple sclerosis should undergo screening for MOG-IgG. These proposed diagnostic criteria require validation but have the potential to improve identification of individuals with MOGAD, which is essential to define long-term clinical outcomes, refine inclusion criteria for clinical trials, and identify predictors of a relapsing versus a monophasic disease course.

MOG and AQP4 Antibodies among Children with Multiple Sclerosis and Controls

OBJECTIVE

The purpose of this study was to determine the frequency of myelin oligodendrocyte glycoprotein (MOG)-IgG and aquaporin-4 (AQP4)-IgG among patients with pediatric-onset multiple sclerosis (POMS) and healthy controls, to determine whether seropositive cases fulfilled their respective diagnostic criteria, to compare characteristics and outcomes in children with POMS versus MOG-IgG-associated disease (MOGAD), and identify clinical features associated with final diagnosis.

METHODS

Patients with POMS and healthy controls were enrolled at 14 US sites through a prospective case-control study on POMS risk factors. Serum AQP4-IgG and MOG-IgG were assessed using live cell-based assays.

RESULTS

AQP4-IgG was negative among all 1,196 participants, 493 with POMS and 703 healthy controls. MOG-IgG was positive in 30 of 493 cases (6%) and zero controls. Twenty-five of 30 patients positive with MOG-IgG (83%) had MOGAD, whereas 5 of 30 (17%) maintained a diagnosis of multiple sclerosis (MS) on re-review of records. MOGAD cases were more commonly in female patients (21/25 [84%] vs 301/468 [64%]; p = 0.044), younger age (mean = 8.2 ± 4.2 vs 14.7 ± 2.6 years; p < 0.001), more commonly had initial optic nerve symptoms (16/25 [64%] vs 129/391 [33%]; p = 0.002), or acute disseminated encephalomyelitis (ADEM; 8/25 [32%] vs 9/468 [2%]; p < 0.001), and less commonly had initial spinal cord symptoms (3/20 [15%] vs 194/381 [51%]; p = 0.002), serum Epstein-Barr virus (EBV) positivity (11/25 [44%] vs 445/468 [95%]; p < 0.001), or cerebrospinal fluid oligoclonal bands (5/25 [20%] vs 243/352 [69%]; p < 0.001).

INTERPRETATION

MOG-IgG and AQP4-IgG were not identified among healthy controls confirming their high specificity for pediatric central nervous system (CNS) demyelinating disease. Five percent of those with prior POMS diagnoses ultimately had MOGAD; and none had AQP4-IgG positivity. Clinical features associated with a final diagnosis of MOGAD in those with suspected MS included initial ADEM phenotype, younger age at disease onset, and lack of EBV exposure. ANN NEUROL 2023;93:271-284.

[Clinical features and modern diagnostic criteria of the disease associated with myelin oligodendrocyte glycoprotein antibody disease]

Demyelinating disease of the central nervous system associated with antibodies to myelin oligodendrocyte glycoprotein (MOGAD) has been proposed to be distinguished from neuromyelitis optica spectrum disorders (NMOSD) into a separate nosological form. The basis for the recognition of nosological independence was the presence of clinical features of this disease and the detection of a specific biomarker in the blood serum of patients - IgG class antibodies to MOG. The article summarizes the current data on the clinical and radiological phenotypes of MOGAD in children and adults and the features of the course of the disease. The requirements for the laboratory diagnosis of the disease and diagnostic criteria for MOGAD proposed by an international group of experts in 2023 are given.

Myelitis features and outcomes in CNS demyelinating disorders: Comparison between multiple sclerosis, MOGAD, and AQP4-IgG-positive NMOSD

Inflammatory myelopathies can manifest with a combination of motor, sensory and autonomic dysfunction of variable severity. Depending on the underlying etiology, the episodes of myelitis can recur, often leading to irreversible spinal cord damage and major long-term disability. Three main demyelinating disorders of the central nervous system, namely multiple sclerosis (MS), aquaporin-4-IgG-positive neuromyelitis optica spectrum disorders (AQP4+NMOSD) and myelin oligodendrocyte glycoprotein-IgG associated disease (MOGAD), can induce spinal cord inflammation through different pathogenic mechanisms, resulting in a more or less profound disruption of spinal cord integrity. This ultimately translates into distinctive clinical-MRI features, as well as distinct patterns of disability accrual, with a step-wise worsening of neurological function in MOGAD and AQP4+NMOSD, and progressive disability accrual in MS. Early recognition of the specific etiologies of demyelinating myelitis and initiation of the appropriate treatment is crucial to improve outcome. In this review article we summarize and compare the clinical and imaging features of spinal cord involvement in these three demyelinating disorders, both during the acute phase and over time, and outline the current knowledge on the expected patterns of disability accrual and outcomes. We also discuss the potential implications of these observations for patient management and counseling.

Myelin Oligodendrocyte Glycoprotein-Associated Disorders

PURPOSE OF REVIEW

Anti-myelin oligodendrocyte glycoprotein (MOG) autoantibodies have become a recognized cause of a pathophysiologically distinct group of central nervous system (CNS) autoimmune diseases. MOG-associated disorders can easily be confused with other CNS diseases such as multiple sclerosis or neuromyelitis optica, but they have a distinct clinical phenotype and prognosis.

RECENT FINDINGS

Most patients with MOG-associated disorders exhibit optic neuritis, myelitis, or acute disseminated encephalomyelitis (ADEM) alone, sequentially, or in combination; the disease may be either monophasic or relapsing. Recent case reports have continued to expand the clinical spectrum of disease, and increasingly larger cohort studies have helped clarify its pathophysiology and natural history.

SUMMARY

Anti-MOG-associated disorders comprise a substantial subset of patients previously thought to have other seronegative CNS diseases. Accurate diagnosis is important because the relapse patterns and prognosis for MOG-associated disorders are unique. Immunotherapy appears to successfully mitigate the disease, although not all agents are equally effective. The emerging large-scale data describing the clinical spectrum and natural history of MOG-associated disorders will be foundational for future therapeutic trials.

Myelin Oligodendrocyte Glycoprotein Antibody-Associated Disease (MOGAD): A Review of Clinical and MRI Features, Diagnosis, and Management

Myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD) is the most recently defined inflammatory demyelinating disease of the central nervous system (CNS). Over the last decade, several studies have helped delineate the characteristic clinical-MRI phenotypes of the disease, allowing distinction from aquaporin-4 (AQP4)-IgG-positive neuromyelitis optica spectrum disorder (AQP4-IgG+NMOSD) and multiple sclerosis (MS). The clinical manifestations of MOGAD are heterogeneous, ranging from isolated optic neuritis or myelitis to multifocal CNS demyelination often in the form of acute disseminated encephalomyelitis (ADEM), or cortical encephalitis. A relapsing course is observed in approximately 50% of patients. Characteristic MRI features have been described that increase the diagnostic suspicion (e.g., perineural optic nerve enhancement, spinal cord H-sign, T2-lesion resolution over time) and help discriminate from MS and AQP4+NMOSD, despite some overlap. The detection of MOG-IgG in the serum (and sometimes CSF) confirms the diagnosis in patients with compatible clinical-MRI phenotypes, but false positive results are occasionally encountered, especially with indiscriminate testing of large unselected populations. The type of cell-based assay used to evaluate for MOG-IgG (fixed vs. live) and antibody end-titer (low vs. high) can influence the likelihood of MOGAD diagnosis. International consensus diagnostic criteria for MOGAD are currently being compiled and will assist in clinical diagnosis and be useful for enrolment in clinical trials. Although randomized controlled trials are lacking, MOGAD acute attacks appear to be very responsive to high dose steroids and plasma exchange may be considered in refractory cases. Attack-prevention treatments also lack class-I data and empiric maintenance treatment is generally reserved for relapsing cases or patients with severe residual disability after the presenting attack. A variety of empiric steroid-sparing immunosuppressants can be considered and may be efficacious based on retrospective or prospective observational studies but prospective randomized placebo-controlled trials are needed to better guide treatment. In summary, this article will review our rapidly evolving understanding of MOGAD diagnosis and management.

Clinical Profile and Treatment Outcome in MOGAD: A Single-Center Case-Series Study in Guiyang, China

Background

The clinical spectrum of myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is expanding over time. However, the long-term management and prognosis of this disorder are still controversial. Therefore, this study aimed to report the clinical profiles and treatment outcomes of MOGAD in our center.

Methods

This was a single-center case-series study. Clinical and para-clinical data, along with treatment outcomes of patients with MOGAD were analyzed.

Results

A total of 27 patients were identified, of which 19 (70%) patients were women, and the median age at disease onset was 40 years (range 20–67). A total of 47 episodes were observed, with optic neuritis (53%) being the most frequent presentation and 60% of them were unilateral. Other presentations included rhombencephalitis (RE) (17%), limbic encephalitis (9%), simultaneous optic neuritis and myelitis (9%), acute disseminated encephalomyelitis (ADEM)-like presentation (6%), myelitis (4%), and ADEM (2%). One patient presenting with RE also met the diagnostic criteria of area postrema syndrome (APS). Another patient with RE presented with imaging characteristics of chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS). A total of 29 lumbar punctures were recorded, among which an elevated protein level was found in 34% of the samples, pleocytosis was found in 14% of the samples, and positive intrathecal oligoclonal bands were found in 19% of the patients. One patient was found to have anti-N-methyl-D-aspartate receptor antibodies both in his serum and cerebrospinal fluid. Intravenous methylprednisolone (IVMP) was administrated for 85% of the attacks while both IVMP and intravenous immunoglobulin were for 6% of the attacks. Moreover, nine patients received maintenance therapy. Among them, six patients were treated with mycophenolate mofetil, three patients were treated with prednisone, rituximab, and teriflunomide, respectively. The median follow-up period was 20 months (range 6–127). At follow-up, twelve (44%) patients experienced a relapsing course, and the median time to the first relapse was 9.5 months (range 2–120). The median Expanded Disability Status Scale score at nadir was 3.5 (range 2–8) and was 0 (range 0–3) at the last follow-up.

Conclusion

The clinical spectrum of MOGAD is heterogenous, wherein APS and CLIPPERS-form can occur. The long-term outcome of MOGAD seems benign. Further studies are warranted to determine the risk factors of relapse and identify the optimal steroid-sparing agents.

Uncommon inflammatory/immune-related myelopathies

The differential diagnosis for immune-mediated myelopathies is broad. Although clinical manifestations overlap, certain presentations are suggestive of a particular myelopathy etiology. Spine MRI lesion characteristics including the length and location, and the pattern of gadolinium enhancement, help narrow the differential diagnosis and exclude an extrinsic compressive cause. The discovery of specific antibodies that serve as biomarkers of myelitis such as aquaporin-4-IgG and myelin-oligodendrocyte -glycoprotein-IgG (MOG-IgG), has improved our understanding of myelitis pathophysiology and facilitated diagnosis. In this review we will focus on the pathophysiology, clinical presentation, imaging findings and treatment and outcomes of uncommon immune-mediated myelopathies.

Clinical characteristics, disease course, and outcomes of paediatric patients with myelin oligodendrocyte glycoprotein-Ab associated disease: A retrospective clinical study

OBJECTIVE

To delineate the outcomes of paediatric patients with myelin oligodendrocyte glycoprotein antibody disease (MOGAD).

METHODS

We retrospectively analyzed the clinical characteristics, treatment, and outcomes of 34 paediatric patients with MOGAD from July 2015 to January 2020.

RESULTS

The median age at disease onset was 75.5 months (range: 19-170 months). The female-to-male ratio was 1:1.1. The median follow-up duration was 34.5 months (range: 14-63 months). Acute disseminated encephalomyelitis (ADEM) was the most common initial phenotype (52.9%), followed by optic neuritis (ON) (20.6%). Children with ADEM were younger than those with ON (P = 0.045). Twenty-eight (82.4%) and 18 (56.3%) children had abnormal brain and spinal magnetic resonance imaging, respectively, during the first acute attack. MOG-abs titers in children with ON were statistically higher than those in children with ADEM (P = 0.04). Thirty-two children accepted glucocorticoid treatment, while 33 (97%) children demonstrated clinical improvement within 1 week, 21 children (61.8%) achieved clinical recovery within 1 month. Eight children (23.5%) suffered a relapse, the median interval between the initial attack and recurrence was 13 (range: 3-36) months. We detected neurological sequelae in seven (20.6%) children, with visual dysfunction being the most common sequela (85.7%).

CONCLUSION

ADEM was the most common phenotype in both monophasic and relapsed paediatric MOGAD, followed by ON. Majority of pediatric MOGAD patients were highly responsive to glucocorticoid. Despite a benign prognosis in most patients, some patients endure neurological sequelae, mainly visual impairment. Patients with initial visual impairment should be carefully evaluated and administered individualized immunotherapy.

Meta-analysis of effectiveness of steroid-sparing attack prevention in MOG-IgG-associated disorder

OBJECTIVE

To estimate the efficacy of the commonly used long-term immunotherapies in myelin oligodendrocyte glycoprotein IgG associated disorder (MOGAD) METHOD: A comprehensive search of the databases including PubMed/MEDLINE, EMBASE, and Cochrane database was performed for all studies that assessed the efficacy of azathioprine (AZA), mycophenolate mofetil (MMF), rituximab (RTX), and maintenance intravenous immunoglobulin (mIVIG) in MOGAD. The random-effect model is used to estimate the standard mean difference (SMD) of annualized relapse rate (ARR) and expanded disability status scale (EDSS), mean ARR, probabilities of relapse and worsening EDSS during treatment.

RESULTS

The initial search identified 714 articles, and 21 satisfied eligibility criteria. All immunotherapies significantly reduced ARR in both pediatric and adult populations. Relapse probabilities and pooled mean ARR (SE: standard error) during therapies were as follow: AZA 53.1% [95%CI 37.4% to 68.2%; ARR 0.291 (0.134)], MMF 38.5% [95%CI 19.4% to 62.0%; ARR 0.836 (0.176)], RTX 48.9% [95%CI 37.8% to 60.2%; ARR 0.629(0.162)], and mIVIG 25.3% [95%CI 14.0% to 41.3%; ARR 0.081 (0.058)]. Only RTX significantly improved EDSS, SMD -0.499 (95%CI -0.996 to -0.003). The proportion of worsening EDSS with immunotherapies were 20.7% (95%CI 8.8% to 41.6%), 8.1% (95%CI 1.1% to 41.2%), and 10.8% (95%CI 3.8% to 26.8%) for AZA, MMF, and RTX, respectively.

CONCLUSION

These commonly used immunotherapies significantly reduced ARR in MOGAD. Only RTX had a significant benefit in EDSS improvement. However, a substantial portion of patients continued to relapse with treatment. Randomized controlled studies are needed to verify these findings and perform head-to-head comparisons among these treatment options.

CNS Demyelinating Attacks Requiring Ventilatory Support With Myelin Oligodendrocyte Glycoprotein or Aquaporin-4 Antibodies

Background and Objective

Severe attacks of myelin oligodendrocyte glycoprotein (MOG) antibody–associated disorder (MOGAD) and aquaporin-4 (AQP4) antibody–positive neuromyelitis optica spectrum disorder (AQP4-NMOSD) may require ventilatory support, but data on episodes are limited, particularly for MOGAD. We sought to compare the frequency, characteristics, and outcomes of MOGAD and AQP4-NMOSD attacks requiring ventilatory support.

Methods

This retrospective descriptive study identified Mayo Clinic patients (January 1, 1996–December 1, 2020) with MOGAD or AQP4-NMOSD and an attack requiring noninvasive or invasive ventilation at Mayo Clinic or an outside facility by searching for relevant terms in their electronic medical record. Inclusion criteria were (1) attack-related requirement for noninvasive (bilevel positive airway pressure or continuous positive airway pressure) or invasive respiratory support (mechanical ventilation); (2) MOG or AQP4 antibody positivity with fulfillment of MOGAD and AQP4-NMOSD clinical diagnostic criteria, respectively; and (3) sufficient clinical details. We collected data on demographics, comorbid conditions, indication for and duration of respiratory support, MRI findings, treatments, and outcomes. The races of those with attacks requiring respiratory support were compared to those without such attacks in MOGAD and AQP4-NMOSD.

Results

Attacks requiring ventilatory support were similarly rare in patients with MOGAD (8 of 279, 2.9%) and AQP4-NMOSD (11 of 503 [2.2%]) (p = 0.63). The age at attack (median years [range]) (MOGAD 31.5 [5–47] vs AQP4-NMOSD 43 [14–65]; p = 0.01) and percentage of female sex (MOGAD 3 of 8 [38%] vs AQP4-NMOSD 10 of 11 [91%]; p = 0.04) differed. The reasons for ventilation differed between MOGAD (inability to protect airway from seizure, encephalitis or encephalomyelitis with attacks of acute disseminated encephalomyelitis 5 [62.5%] or unilateral cortical encephalitis 3 [37.5%]) and AQP4-NMOSD (inability to protect airway from cervical myelitis 9 [82%], rhombencephalitis 1 [9%], or combinations of both 1 [9%]). Median ventilation duration for MOGAD was 2 days (range 1–7 days) vs 19 days (range 6–330 days) for AQP4-NMOSD (p = 0.01). All patients with MOGAD recovered, but 2 of 11 (18%) patients with AQP4-NMOSD died of the attack. For AQP4-NMOSD, Black race was overrepresented for attacks requiring ventilatory support vs those without these episodes (5 of 11 [45%] vs 88 of 457 [19%]; p = 0.045).

Discussion

Ventilatory support is rarely required for MOGAD and AQP4-NMOSD attacks, and the indications differ. Compared to MOGAD, these attacks in AQP4-NMOSD may have higher morbidity and mortality, and those of Black race were more predisposed, which we suspect may relate to socially mediated health inequality.

Age-dependent favorable visual recovery despite significant retinal atrophy in pediatric MOGAD: how much retina do you really need to see well?

Background

To investigate age-related severity, patterns of retinal structural damage, and functional visual recovery in pediatric and adult cohorts of myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) optic neuritis (ON).

Methods

All MOGAD patients from the 5 participating centers were included. Patients with initial manifestation <18 years were included in the pediatric (MOGAD^ped) cohort and patients with ≥18 years in the adult (MOGAD^adult) cohort. For patients with MOGAD ON, examinations at least ≥6 months after ON onset were included in the analyses. Using spectral domain optical coherence tomography (SD-OCT), we acquired peripapillary retinal nerve fiber layer thickness (pRNFL) and volumes of combined ganglion cell and inner plexiform layer (GCIPL). High- and 2.5% low-contrast visual acuity (HCVA, LCVA) and visual-evoked potentials (VEP) were obtained.

Results

Twenty MOGAD^ped (10.3±3.7 years, 30 MOGAD ON eyes) and 39 MOGAD^adult (34.9±11.6 years, 42 MOGAD ON eyes) patients were included. The average number of ON episodes per ON eye was similar in both groups (1.8±1.3 and 2.0±1.7). In both pediatric and adult MOGAD, ON led to pronounced neuroaxonal retinal atrophy (pRNFL: 63.1±18.7 and 64.3±22.9 μm; GCIPL: 0.42±0.09 and 0.44±0.13 mm³, respectively) and moderate delay of the VEP latencies (117.9±10.7 and 118.0±14.5 ms). In contrast, visual acuity was substantially better in children (HCVA: 51.4±9.3 vs. 35.0±20.6 raw letters, p=0.001; LCVA: 22.8±14.6 vs. 13.5±16.4, p=0.028). Complete visual recovery (HCVA-logMAR 0.0) occurred in 73.3% of MOGAD^ped and 31% MOGAD^adults ON eyes, while 3.3% and 31% demonstrated moderate to severe (logMAR > 0.5) visual impairment. Independent of retinal atrophy, age at ON onset significantly correlated with visual outcome.

Conclusion

Pediatric MOGAD ON showed better visual recovery than adult MOGAD ON despite profound and almost identical neuroaxonal retinal atrophy. Age-related cortical neuroplasticity may account for the substantial discrepancy between structural changes and functional outcomes.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12974-021-02160-9.