Retrospective analysis of children with myelin oligodendrocyte glycoprotein antibody-related disorders

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

BACKGROUND AND PURPOSE

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

MATERIALS AND METHODS

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

RESULTS

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

CONCLUSIONS

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

Clinical Features of Patients with Myelin Oligodendrocyte Glycoprotein Antibody-Associated Disease and Isolated Seizure Symptoms

Background

Myelin oligodendrocyte glycoprotein (MOG) antibody-associated encephalitis is a new clinical phenotype of inflammatory demyelinating diseases. Some MOG antibody-positive patients with central nervous system demyelinating events present with isolated seizures. However, there are gaps in the epidemiological knowledge regarding seizures with MOG antibody-associated encephalitis in adults. This study characterized the clinical features and treatment of MOG antibody-positive patients with isolated seizures.

Methods

We reviewed all the patients admitted to Tianjin Huanhu Hospital between Jan. 1st 2017 and Jan. 1st 2022, to screen the MOG antibody-positive patients with isolated seizures, and collected the concerned patients' information regarding epidemiology, clinical presentations, laboratory and radiological characteristics, electroencephalogram (EEG), treatments, and prognoses.

Results

We collected six MOG antibody-positive adult patients who had isolated symptomatic seizures. The mean age of the patients was 33 years (range, 29-40 years), and five (83.3%) were men. All patients presented with motor seizures, five (83.3%) had cognitive dysfunction, and only one (16.7%) had status epilepticus. Five (83.3%) patients had a good response to immunotherapy and antiseizure medications; only one had a sequela. The cerebrospinal fluid or serum anti-MOG antibody test turned negative over time.

Discussion

The most common seizure type in patients with MOG antibody-associated encephalitis with isolated seizures was focal to bilateral tonic-clonic seizures, and most patients had a good prognosis. Adding antiseizure medications were beneficial for MOG antibody-positive patients with seizures. Relapses and sequelae were associated with low-dose, short-time, or delayed therapy, and wide-range demyelinating brain damage.

Visual outcome measures in pediatric myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD)

BACKGROUND

Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) comprises various age-dependent clinical phenotypes and may be monophasic, multiphasic, or chronic. Optic neuritis (ON) is a common manifestation and frequently appears in combination with other MOGAD phenotypes, particularly in young children. Despite permanent structural damage to the retinal nerve fiber layer (RNFL), children often experience complete visual recovery.

AIMS

To analyze the progression and impact of MOGAD on the visual system of pediatric patients independently of the history of ON.

METHODS

This retrospective study included children who met specific criteria: myelin oligodendrocyte glycoprotein (MOG) immunoglobulin G (IgG) seropositivity, acute presentation of MOGAD, and written general consent. Main outcome measures were global peripapillary retinal nerve fiber layer (pRNFL) thickness, and near and distance visual acuity, analyzed using descriptive statistics.

RESULTS

We identified 10 patients with median age of 7.7 years at first event: 7 patients manifested with acute disseminated encephalomyelitis (ADEM) (with ON 5/7, ADEM only 1/7, with transverse myelitis (TM) 1/7), 2 with isolated ON, and 1 patient with neuromyelitis optica spectrum disorder (NMOSD)-like phenotype with ON. Among ON patients, 5/8 were affected bilaterally, with 3 initially diagnosed with unilateral ON but experiencing subsequent involvement of the fellow eye. None of the patients without previous ON showed a deterioration of visual acuity and, if evaluated, a reduction of the pRNFL.

CONCLUSION

Most pediatric MOGAD-ON patients in our cohort presented with acute vison loss and optic disc edema. All patients achieved complete visual recovery, independent of number of relapses or initial visual loss. The pRNFL thickness decreased for several months and stabilized at reduced levels after 12 months in the absence of further relapses. MOGAD may not have subclinical/'silent' effects on the visual system, as visual acuity and pRNFL were not affected in patients without ON.

Clinical spectrum of myelin oligodendrocyte glycoprotein antibody-associated disease in Brazil: a single-center experience

BACKGROUND

 Anti-myelin oligodendrocyte glycoprotein (anti-MOG) antibody-associated disease (MOGAD) is an immune-mediated neurological disorder with a broad spectrum of clinical presentation that is often difficult to distinguish from other demyelinating diseases, such as multiple sclerosis and neuromyelitis optica spectrum disorder.

OBJECTIVE

 To describe the clinical and paraclinical characteristics of MOGAD in a Brazilian tertiary center.

METHODS

 We retrospectively reviewed the records of adult and pediatric patients who tested positive for anti-MOG antibodies and presented with clinical and radiological diseases compatible with MOGAD.

RESULTS

 Forty-one patients (10 children) were included: 56% female, 58% Caucasian, mean age at onset 31 years (range 6-64), with a mean disease duration of 59.6 months (range 1-264 months). The most frequent onset presentation was optic neuritis (68%), acute disseminated encephalomyelitis (ADEM, 12%), and myelitis (10%). A monophasic disease course was observed in 49%. EDSS median was 2.1 at the last visit. Most patients (83%) were under continuous immunosuppressive treatment. Azathioprine was the first-line treatment in 59%. In all ADEM cases, conus, and root involvement was radiologically observed on MRI.

CONCLUSION

 Brazilian MOGAD patients presented with a similar spectrum of previously reported MOGAD phenotypes. Conus and spinal root involvement seems to be frequently present in MOGAD-ADEM and could serve as radiologic characteristics of this clinical entity.

Myelin Oligodendrocyte Glycoprotein (MOG) Associated Diseases: Updates in Pediatric Practice

Myelin oligodendrocyte glycoprotein (MOG) is a membrane bound protein found on the surface of oligodendrocyte cells and the outermost surface of myelin sheaths. MOG is posited to play a role as a cell surface receptor or cell adhesion molecule, though there is no definitive answer to its exact function at this time. In the last few decades, there has been a recognition of anti-MOG-antibodies (MOG-Abs) in association with a variety of neurologic conditions, though primarily demyelinating and white matter disorders. In addition, MOG associated disease (MOGAD) appears to have a predilection for pediatric populations and in some patients may have a relapsing course. There has been considerable debate as to whether MOG-Abs are truly directly pathogenic or a disease biomarker associated with neuorinflammatory disease. In this manuscript we will review the current literature surrounding MOGAD, review new clinical phenotypes, discuss treatment and prognosis, and provide insight into potential future directions that studies may focus on.

Attack phenotypes and disease course in pediatric MOGAD

Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is an autoimmune demyelinating condition that affects children differently than adults. We performed a literature review to assess the presentation and clinical course of pediatric MOGAD. The most common initial phenotype is acute disseminated encephalomyelitis, especially among children younger than five years, followed by optic neuritis (ON) and/or transverse myelitis. Approximately one-quarter of children with MOGAD have at least one relapse that typically occurs within three years of disease onset and often includes ON, even if ON was not present at onset. Clinical risk factors for a relapsing course have not been elucidated.

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.

Clinical characteristics and prognosis of pediatric myelin oligodendrocyte glycoprotein antibody-associated diseases in China

Background

Research on myelin oligodendrocyte glycoprotein antibody (MOG-Ab)-associated disease (MOGAD) among Chinese children is relatively rare. Therefore, this study aimed to explore and analyze the clinical characteristics and prognoses of Chinese children with acquired demyelinating syndromes (ADSs) who tested positive or negative for MOG-Ab.

Methods

The clinical data of children with MOGAD who were treated in the Department of Neurology at Shanghai Children's Hospital from January 2017 to October 2021 were retrospectively collected.

Results

Among 90 children with ADSs, 30 were MOG-Ab-positive, and 60 were MOG-Ab-negative. MOG-Ab-positive children experienced more prodromal infections than did MOG-Ab-negative children (P < 0.05). Acute disseminated encephalomyelitis was the most common ADSs in both groups. There were ten cases of a rebound increase in MOG-Ab titers. There were significant differences in the MOG titer-related prognosis and disease time course between the disease relapse group and the non-relapse group (P < 0.01). Among the MOG-Ab-positive patients, the most affected brain areas detected via magnetic resonance imaging (MRI) were the temporal lobe, cerebellar hemispheres, brainstem, and periventricular lesions. The most common shapes of the lesions were commas, triangles, or patches. The average improvement time based on brain MRI was much longer in MOG-Ab-positive than in MOG-Ab-negative children (P < 0.05). The initial treatment time correlated with the disease time course, and the prognosis may be affected by the disease time course and serum MOG-Ab titer (P < 0.05).

Conclusion

The clinical characteristics and imaging features of ADSs differed between MOG-Ab-positive and MOG-Ab-negative children. In addition to existing treatment plans, additional diagnoses and treatment plans should be developed to reduce recurrence and improve the prognoses of children with MOGAD.

Spectrum of anti-myelin oligodendrocyte glycoprotein antibody (MOG-Ab)-associated diseases: an Indian perspective

Myelin oligodendrocyte glycoprotein antibody (MOG-Ab) is involved in the pathogenesis of central nervous system (CNS) demyelination disorders. We aimed to explore the spectrum of MOG-Ab-associated diseases in eastern India. A single-center, prospective observational study was done over a period of 2 years in a tertiary care hospital of eastern India. Patients with CNS demyelination disorders who tested positive for MOG-Ab using live cell-based assay were included in the study; while, those with age less than 1 year, documented preexisting CNS structural lesions, developmental delays or diagnosed multiple sclerosis were excluded. Demographic profile, clinical spectrum, disease course, radiological features as well as response to treatment were analyzed among included patients. Twenty MOG-Ab-positive patients were included (M:F 1:1.85). The median age of symptom onset was 10.5 years. The median follow-up of patients was 13 months. Acute disseminated encephalomyelitis (ADEM) was the commonest presentation at first attack (55%), followed by optic neuritis (ON) (45%). Patients with ADEM had a significantly lower age at first attack (p = 0.025). Monophasic and relapsing disease courses were seen in 45% and 55% patients, respectively. While all patients with only ADEM had a monophasic course, 77.8% with ON had a relapsing course. Among patients who presented with isolated transverse myelitis, 75% had a monophasic course and all had disease confined to the spinal cord. Good response to corticosteroids was seen in majority of participants. Second-line drugs were needed in 55% patients, rituximab being the commonest second-line agent used. 35% patients had significant disability (EDSS > 4) at last follow-up. MOG-Ab-associated diseases have diverse clinical phenotypes characterized by age-dependent pattern-specific courses.

The Clinical, Radiologic, and Prognostic Differences Between Pediatric and Adult Patients With Myelin Oligodendrocyte Glycoprotein Antibody-Associated Encephalomyelitis

Purpose: To evaluate the clinical differences between pediatric and adult patients with myelin oligodendrocyte glycoprotein antibody-associated encephalomyelitis (MOG-EM).

Methods: We retrospectively reviewed the clinical features of pediatric and adult patients with MOG-EM in our center between November 2015 and October 2020.

Results: Twenty-eight pediatric patients and 25 adults were admitted to our study. Bilateral optic neuritis (BON) was the most common initial phenotype in the pediatric group but less common in the adult group (28.57 vs. 0%, p = 0.0119). Almost half of the adult patients presented with neuromyelitis optica spectrum disease (NMOSD), which was less prevalent among the pediatrics (48 vs. 21.43%, p = 0.0414). Visual impairment was the most common symptom in both groups during the initial attack (pediatric group, 39.29%; adult group, 64%) and throughout the full course (pediatric group, 57.14%; adult group, 72%). More pediatric patients suffered from fever than adult patients at onset (pediatric group, 28.57%; adult group, 4%; p = 0.0442) and throughout the full course (pediatric group, 39.29%; adult group, 12%; p = 0.0245). Multiple patchy lesions in subcortical white matter (pediatric group, 40.74%; adult group, 45%), periventricular (pediatric group, 25.93%; adult group, 35%), infratentorial (pediatric group, 18.52%; adult group, 30%) and deep gray matter (pediatric group, 25.93%; adult group, 20%) were frequent in all cases, no significant difference was found between the two groups, while bilateral optic nerve involvement was more frequent in pediatric group (61.54 vs. 14.29%, p = 0.0042) and unilateral optic nerve involvement was higher in adult group (64.29 vs. 15.38%, p = 0.0052). At the last follow-up, adult patients had a higher average EDSS score (median 1.0, range 0–3) than pediatrics (median 0.0, range 0–3), though not significant (p = 0.0752). Patients aged 0–9 years (61.54%) and 10–18 years (70%), and patients presenting with encephalitis/meningoencephalitis (100%) and ADEM (75%) were more likely to recover fully.

Conclusions: Visual impairment was the dominant symptom in both pediatric and adult patients, while fever was more frequent in pediatric patients. Data suggested that BON and bilateral optic nerve involvement were more common in pediatric cases whereas NMOSD and unilateral optic nerve involvement were more prevalent in adults. The younger patients and patients presenting with encephalitis/meningoencephalitis and ADEM tended to recover better.

E.U. paediatric MOG consortium consensus: Part 1 - Classification of clinical phenotypes of paediatric myelin oligodendrocyte glycoprotein antibody-associated disorders

Over the past few years, increasing interest in the role of autoantibodies against myelin oligodendrocyte glycoprotein (MOG-abs) as a new candidate biomarker in demyelinating central nervous system diseases has arisen. MOG-abs have now consistently been identified in a variety of demyelinating syndromes, with a predominance in paediatric patients. The clinical spectrum of these MOG-ab-associated disorders (MOGAD) is still expanding and differs between paediatric and adult patients. This first part of the Paediatric European Collaborative Consensus emphasises the diversity in clinical phenotypes associated with MOG-abs in paediatric patients and discusses these associated clinical phenotypes in detail. Typical MOGAD presentations consist of demyelinating syndromes, including acute disseminated encephalomyelitis (ADEM) in younger, and optic neuritis (ON) and/or transverse myelitis (TM) in older children. A proportion of patients experience a relapsing disease course, presenting as ADEM followed by one or multiple episode(s) of ON (ADEM-ON), multiphasic disseminated encephalomyelitis (MDEM), relapsing ON (RON) or relapsing neuromyelitis optica spectrum disorders (NMOSD)-like syndromes. More recently, the disease spectrum has been expanded with clinical and radiological phenotypes including encephalitis-like, leukodystrophy-like, and other non-classifiable presentations. This review concludes with recommendations following expert consensus on serologic testing for MOG-abs in paediatric patients, the presence of which has consequences for long-term monitoring, relapse risk, treatments, and for counselling of patient and families. Furthermore, we propose a clinical classification of paediatric MOGAD with clinical definitions and key features. These are operational and need to be tested, however essential for future paediatric MOGAD studies.

E.U. paediatric MOG consortium consensus: Part 2 - Neuroimaging features of paediatric myelin oligodendrocyte glycoprotein antibody-associated disorders

Imaging plays a crucial role in differentiating the spectrum of paediatric acquired demyelinating syndromes (ADS), which apart from myelin oligodendrocyte glycoprotein antibody associated disorders (MOGAD) includes paediatric multiple sclerosis (MS), aquaporin-4 antibody neuromyelitis optica spectrum disorders (NMOSD) and unclassified patients with both monophasic and relapsing ADS. In contrast to the imaging characteristics of children with MS, children with MOGAD present with diverse imaging patterns which correlate with the main demyelinating phenotypes as well as age at presentation. In this review we describe the common neuroradiological features of children with MOGAD such as acute disseminated encephalomyelitis, optic neuritis, transverse myelitis, AQP4 negative NMOSD. In addition, we report newly recognized presentations also associated with MOG-ab such as the 'leukodystophy-like' phenotype and autoimmune encephalitis with predominant involvement of cortical and deep grey matter structures. We further delineate the features, which may help to distinguish MOGAD from other ADS and discuss the future role of MR-imaging in regards to treatment decisions and prognosis in children with MOGAD. Finally, we propose an MRI protocol for routine examination and discuss new imaging techniques, which may help to better understand the neurobiology of MOGAD.

E.U. paediatric MOG consortium consensus: Part 4 - Outcome of paediatric myelin oligodendrocyte glycoprotein antibody-associated disorders

There is increasing knowledge on the role of antibodies against myelin oligodendrocyte glycoprotein (MOG-abs) in acquired demyelinating syndromes and autoimmune encephalitis in children. Better understanding and prediction of outcome is essential to guide treatment protocol decisions. Therefore, this part of the Paediatric European Collaborative Consensus provides an oversight of existing knowledge of clinical outcome assessment in paediatric MOG-ab-associated disorders (MOGAD). The large heterogeneity in disease phenotype, disease course, treatment and follow-up protocols is a major obstacle for reliable prediction of outcome. However, the clinical phenotype of MOGAD appears to be the main determinant of outcome. Patients with a transverse myelitis phenotype in particular are at high risk of accruing neurological disability (motor and autonomic), which is frequently severe. In contrast, having a single episode of optic neuritis any time during disease course is broadly associated with a lower risk of persistent disability. Furthermore, MOG-ab-associated optic neuritis often results in good functional visual recovery, although retinal axonal loss may be severe. The field of cognitive and behavioural outcome and epilepsy following demyelinating episodes has not been extensively explored, but in recent studies acute disseminated encephalomyelitis (-like) phenotype in the young children was associated with cognitive problems and epilepsy in long-term follow-up. In conclusion, main domains of importance in determining clinical outcome in paediatric MOGAD are visual, motor, autonomic and cognitive function. A standardised evaluation of these outcome domains in all children is of importance to allow adequate rehabilitation and follow-up.

Risk factors for academic difficulties in children with myelin oligodendrocyte glycoprotein antibody-associated acute demyelinating syndromes

AIM

To describe cognitive abilities through the evaluation of academic difficulties in children with acute demyelinating syndromes (ADS) and myelin oligodendrocyte glycoprotein (MOG) antibodies.

METHOD

This was an observational, retrospective study of a French paediatric cohort that included children aged 18 years and younger. Clinical, biological, and imaging data were collected and academic outcome was measured.

RESULTS

Seventy-six children were included in the study with a mean (SD) follow-up of 4 years 7 months (6y 4mo). Median age at disease onset was 9 years 1 months (interquartile range=4y 7mo-13y 11mo; 36 females, 40 males). Thirty-six children relapsed and 20 had academic difficulties at the last follow-up. Academic difficulties, as well as deep grey matter and putaminal lesions (p=0.047 and p=0.006 respectively), were significantly more prevalent in children aged 10 years and younger (p=0.02). Using univariate binary regression analysis, we found that age at disease onset of 10 years and younger (odds ratio [OR] 3.72 [95% confidence interval {CI} 1.19-11.64]; p=0.024), acute disseminated encephalomyelitis at disease onset (OR 52.5 [95% CI 5.97-461.4]; p<0.001), and deep grey matter lesions (OR 17.33 [95% CI 3.87-77.72]; p<0.001) were associated with academic difficulties.

INTERPRETATION

MOG antibody-associated ADS have distinct clinical and radiological patterns that are age-dependent. Indirect cognitive evaluation through academic difficulties was prevalent in younger children and is associated with specific clinical and magnetic resonance imaging factors that need to be considered earlier on when assessing this patient population.

Understanding Pediatric Neuroimmune Disorder Conflicts: A Neuroradiologic Approach in the Molecular Era

Neuroimmune disorders in children are a complex group of inflammatory conditions of the central nervous system with diverse pathophysiologic mechanisms and clinical manifestations. Improvements in antibody analysis, genetics, neuroradiology, and different clinical phenotyping have expanded knowledge of the different neuroimmune disorders. The authors focus on pediatric-onset myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease, which is a new entity in the spectrum of inflammatory demyelinating diseases, distinct from both multiple sclerosis (MS) and anti-aquaporin-4 (AQP4) antibody neuromyelitis optica spectrum disorders (NMOSDs). The authors review the importance of an optimized antibody-detection assay, the frequency of MOG antibodies in children with acquired demyelinating syndrome (ADS), the disease course, the clinical spectrum, proposed diagnostic criteria, and neuroimaging of MOG antibody-associated disease. Also, they outline differential diagnosis from other neuroimmune disorders in children according to the putative primary immune mechanism. Finally, they recommend a diagnostic algorithm for the first manifestation of ADS or relapsing ADS that leads to four demyelinating syndromes: MOG antibody-associated disease, AQP4 antibody NMOSDs, MS, and seronegative relapsing ADS. This diagnostic approach provides a framework for the strategic role of neuroradiology in diagnosis of ADS and decision making, to optimize patient care and treatment outcome in concert with clinicians. Online supplemental material is available for this article. ^©RSNA, 2020.

Rituximab in children with myelin oligodendrocyte glycoprotein antibody and relapsing neuroinflammatory disease

The aim of this study was to evaluate tolerability of and response to rituximab in children with myelin oligodendrocyte glycoprotein (MOG) antibody-positive relapsing neuroinflammatory disease. This was an observational study of prospectively collected data on 12 consecutive children (eight females, four males; median age at onset 10y 6mo [interquartile range {IQR} 7y 2mo-12y 5mo], median follow-up 2y 1mo [IQR 1y 7mo-2y 6mo]) with central nervous system inflammation and persistent serum MOG immunoglobulin G positivity more than 12 weeks after clinical presentation. Patients received a standardized rituximab treatment protocol. MOG antibody testing was performed following standardized cell-based methods. Median clinical follow-up after rituximab induction was 2 years (IQR 1y 7mo-2y 10mo). The relapse rate in the first 12 months posttreatment was 0 (IQR 0-0). After rituximab, two patients relapsed during B-cell suppression and four showed clinical or radiological disease recurrences at B-cell reconstitution. Mild-to-moderate infusion related adverse events occurred in two patients. Leukopenia developed in seven patients and serum immunoglobulin suppression in five patients with no significant age effect on the risk of their development. None developed severe life-threatening events. Rituximab-induced B-cell suppression was associated with absence of relapses in 10 patients who were MOG-positive with recurrent disease. Rituximab was well tolerated. The most frequent adverse effects were hypogammaglobulinemia and leukopenia. We recommend monitoring of complete blood counts and immunoglobulins in this population. WHAT THIS PAPER ADDS: Rituximab appears to control disease in most anti-myelin oligodendrocyte glycoprotein-positive patients with relapsing neuroinflammatory disease. Rituximab was associated with transitory, mild-to-moderate infusion-related effects. Half of patients treated with rituximab developed leukopenia or hypogammaglobulinemia. No opportunistic infections were observed.

Pediatric NMOSD: A Review and Position Statement on Approach to Work-Up and Diagnosis

Neuromyelitis Optica Spectrum Disorder (NMOSD) is an inflammatory demyelinating disease of the central nervous system (CNS) primarily affecting the optic nerves and spinal cord, but also involving other regions of the CNS including the area postrema, periaqueductal gray matter, and hypothalamus. Knowledge related to pediatric manifestations of NMOSD has grown in recent years, particularly in light of newer information regarding the importance of not only antibodies to aquaporin 4 (AQP4-IgG) but also myelin oligodendrocyte glycoprotein (MOG-IgG) in children manifesting clinically with this syndrome. In this review, we describe the current state of the knowledge related to clinical manifestations, diagnosis, and chronic therapies for children with NMOSD, with emphasis on literature that has been published in the last 5 years. Following the review, we propose recommendations for the assessment/follow up clinical care, and treatment of this population.

Diagnostic Considerations in Acute Disseminated Encephalomyelitis and the Interface with MOG Antibody

Acute disseminated encephalomyelitis (ADEM) is a common yet clinically heterogenous syndrome characterized by encephalopathy, focal neurologic findings, and abnormal neuroimaging. Differentiating ADEM from other demyelinating disorders of childhood can be difficult and appropriate interpretation of the historical, clinical, and neurodiagnostic components of a patient's presentation is critical. Myelin oligodendrocyte glycoprotein (MOG) antibody-associated diseases are a recently recognized set of disorders, which include ADEM presentations, among other phenotypes. This review article discusses the clinical diagnosis, differential diagnosis, interpretation of data, and treatment/prognosis of this unique syndrome with distinctive review of the spectrum of MOG antibodies.