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

Higher incidence of acute symptomatic seizures in probable antibody-negative pediatric autoimmune encephalitis than in major antibody-positive autoimmune encephalitis

Purpose

To delineate the characteristics of probable antibody-negative pediatric autoimmune encephalitis (probable Ab-negative AE), we compared the clinical features of probable Ab-negative AE to those of major antibody-positive AE.

Methods

We retrospectively reviewed the clinical features of 18 patients with probable Ab-negative AE, 13 with anti-N-methyl-D-aspartate receptor encephalitis (NMDARE), and 13 with myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD). Clinical characteristics, neuroimaging findings, treatments, and outcomes were analyzed.

Results

The age of onset and length of hospital stay were significantly higher in the NMDARE group than in the other groups (p = 0.02 and p < 0.01). Regarding initial neurological symptoms, acute symptomatic seizures in the probable Ab-negative AE group (67%) were significantly more frequent than in the NMDARE (15%) and MOGAD (23%) groups (p < 0.01). Paraclinical evidence of neuroinflammation within 1 month of disease onset revealed that single-photon emission computed tomography (SPECT) detected abnormal alterations in 14/14 (100%), cerebrospinal fluid (CSF) analysis in 15/18 (83%), and magnetic resonance imaging (MRI) in 11/18 (61%) in patients with probable Ab-negative AE. In the probable Ab-negative AE group, seven patients (39%) developed autoimmune-associated epilepsy, whereas one patient (8%) had both NMDARE and MOGAD (not statistically significant, p = 0.07).

Conclusion

Patients with probable Ab-negative AE exhibited acute symptomatic seizures as initial neurological symptoms significantly more frequently. They developed autoimmune-associated epilepsy more frequently than those with NMDARE and MOGAD, which was not statistically significant. SPECT within 1 month of disease onset might be a valuable surrogate marker of ongoing neuroinflammation and neuronal dysfunction, even in patients with negative MRI findings.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

Clinical characteristics of patients with myelin oligodendrocyte glycoprotein antibodies

PURPOSE OF REVIEW

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

RECENT FINDINGS

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

SUMMARY

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

Update in Pediatric Neurocritical Care: What a Neurologist Caring for Critically Ill Children Needs to Know

Currently nearly one-quarter of admissions to pediatric intensive care units (PICUs) worldwide are for neurocritical care diagnoses that are associated with significant morbidity and mortality. Pediatric neurocritical care is a rapidly evolving field with unique challenges due to not only age-related responses to primary neurologic insults and their treatments but also the rarity of pediatric neurocritical care conditions at any given institution. The structure of pediatric neurocritical care services therefore is most commonly a collaborative model where critical care medicine physicians coordinate care and are supported by a multidisciplinary team of pediatric subspecialists, including neurologists. While pediatric neurocritical care lies at the intersection between critical care and the neurosciences, this narrative review focuses on the most common clinical scenarios encountered by pediatric neurologists as consultants in the PICU and synthesizes the recent evidence, best practices, and ongoing research in these cases. We provide an in-depth review of (1) the evaluation and management of abnormal movements (seizures/status epilepticus and status dystonicus); (2) acute weakness and paralysis (focusing on pediatric stroke and select pediatric neuroimmune conditions); (3) neuromonitoring modalities using a pathophysiology-driven approach; (4) neuroprotective strategies for which there is evidence (e.g., pediatric severe traumatic brain injury, post-cardiac arrest care, and ischemic stroke and hemorrhagic stroke); and (5) best practices for neuroprognostication in pediatric traumatic brain injury, cardiac arrest, and disorders of consciousness, with highlights of the 2023 updates on Brain Death/Death by Neurological Criteria. Our review of the current state of pediatric neurocritical care from the viewpoint of what a pediatric neurologist in the PICU needs to know is intended to improve knowledge for providers at the bedside with the goal of better patient care and outcomes.

Clinico-radiologic Spectrum and Outcome of Pediatric Acquired Demyelinating Disorders of Central Nervous System: A Retrospective Indian Tertiary Care Hospital Cohort

BACKGROUND

 Pediatric acquired demyelinating syndrome (ADS) constitutes a group of treatable disorders with acute neurologic dysfunction. Neuroimaging has played a significant role in diagnosis of ADS. We describe clinico-radiologic spectrum, outcomes, and comparison of the groups: acute disseminated encephalomyelitis (ADEM), neuromyelitis optica spectrum disorder (NMOSD), clinically isolated syndrome (CIS), multiple sclerosis (MS), and myelin oligodendrocyte glycoprotein antibody-associated disorders (MOGAD).

METHODS

 Retrospective review of 70 children with ADS at a tertiary care hospital over 15 years (2008-2023) was performed. Diagnosis was assigned as per International Pediatric Multiple Sclerosis Study Group criteria 2016. Fisher's exact and chi-square tests were applied.

RESULTS

 Thirty-nine boys and 31 girls aged 8.2 ± 4.0 years with CIS (n = 27), ADEM (n = 16), NMOSD (n = 13), MS (n = 1), and MOGAD (n = 13) were included. Clinical syndromes with positive significant association included polyfocal symptoms, encephalopathy in ADEM, optic neuritis (ON) in MOGAD, brainstem, area postrema syndrome in NMOSD. MOGAD presented with atypical presentations like prolonged fever (PF; 76.9%) and aseptic meningitis (23%). Seropositivity for myelin oligodendrocyte glycoprotein immunoglobulin-G was 62% and for NMO-IgG 2.6%. Neuroimaging of MOGAD showed lesions predominantly in basal ganglia/thalami (69.2%), optic nerve (46.2%), and cerebellum (46.2%). Imaging patterns between ADEM and MOGAD were comparable except for more ON (p = 0.004), spinal cord (p = 0.01), and cerebellar lesions (p = 0.03) in MOGAD. Area postrema lesion was unique to NMOSD. All patients received immunotherapy, of whom 91.4% (n = 64) had good recovery, 8.6% (n = 6) had functional limitation on modified Rankin scale at discharge, and 12 (17.1%) relapsed.

CONCLUSION

 The largest group was CIS. Seropositivity of MOG was high with atypical presentations like PF and aseptic meningitis. Specific neuroimaging patterns correlated with ADS categories. Short-term outcome with immunotherapy was favorable in spite of relapses.

Blood parameters in pediatric myelin oligodendrocyte glycoprotein antibody-associated disorders

BACKGROUND AND OBJECTIVES

Patients with myelin oligodendrocyte glycoprotein antibody-associated disorders (MOGAD) clinically present e.g. with acute disseminated encephalomyelitis (ADEM), optic neuritis (ON), transverse myelitis (TM) or aquaporin-4-IgG (AQP4-IgG) negative neuromyelitis optica spectrum disorders (NMOSD)-like phenotypes. We aimed to analyze and compare blood parameters in children with MOGAD, AQP4-IgG-positive NMOSD (hence NMOSD), multiple sclerosis (MS) and healthy controls (HC).

METHODS

We evaluated differences in complete blood counts (CBC), neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), monocyte-to-lymphocyte ratio (MLR) and C-reactive protein (CRP) between these four groups and within the groups between clinical attack, acute treatment and remission.

RESULTS

Our cohort consisted of 174 children and adolescents with a total of 550 timepoints: 66 patients had MOGAD (202 timepoints), 11 NMOSD (76 timepoints), 58 MS (219 timepoints) and 39 were HC (53 timepoints). At clinical attack, leukocyte counts were elevated in MOGAD compared to remission (p < 0.001) and compared to all other groups (p < 0.001). NLR was high in MOGAD and NMOSD, and PLR was high in NMOSD, however, after correction for multiple testing these findings did not remain significant. While glucocorticoids caused an increase of leukocyte counts and NLR in NMOSD and MS, these values remained stable during acute treatment in MOGAD. In remission, NLR normalized in MOGAD, while it stayed high in NMOSD. PLR increased in NMOSD and was significantly higher compared to all other groups.

DISCUSSION

Some blood parameters, mainly leukocyte and differential counts, might help clinicians to evaluate disease activity, differentiate relapses from pseudo-relapses and even distinguish between different disease entities.

MOG Antibodies Restricted to CSF in Children With Inflammatory CNS Disorders

OBJECTIVES

To assess the clinical significance of myelin oligodendrocyte glycoprotein antibodies (MOG-abs) restricted to CSF in children with inflammatory CNS disorders.

METHODS

Patients included 760 children (younger than 18 years) from 3 multicenter prospective cohort studies: (A) acquired demyelinating syndromes, including acute disseminated encephalomyelitis (ADEM); (B) non-ADEM encephalitis; and (C) noninflammatory neurologic disorders. For all cases, paired serum/CSF samples were systematically examined using brain immunohistochemistry and live cell-based assays.

RESULTS

A total of 109 patients (14%) had MOG-abs in serum or CSF: 79 from cohort A, 30 from B, and none from C. Of these, 63 (58%) had antibodies in both samples, 37 (34%) only in serum, and 9 (8%) only in CSF. Children with MOG-abs only in CSF were older than those with MOG-abs only in serum or in both samples (median 12 vs 6 vs 5 years, p = 0.0002) and were more likely to have CSF oligoclonal bands (86% vs 12% vs 7%, p = 0.0001) and be diagnosed with multiple sclerosis (6/9 [67%] vs 0/37 [0%] vs 1/63 [2%], p < 0.0001).

DISCUSSION

Detection of MOG-abs in serum or CSF is associated with CNS inflammatory disorders. Children with MOG-abs restricted to CSF are more likely to have CSF oligoclonal bands and multiple sclerosis than those with MOG-abs detectable in serum.

Clinical analysis of myelin oligodendrocyte glycoprotein antibody-associated disease in a diverse cohort of children: A single-center observational study

BACKGROUND

Prognostic markers for relapse and neurological disability following the first clinical event in children with myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) remain lacking. We investigated the clinical profiles and early prognostic factors associated with relapsing disease or impaired functional outcome in a large single-center cohort of pediatric MOGAD.

METHODS

We retrospectively analyzed the clinical and paraclinical data and treatment outcomes of children with MOGAD seen at Children's Health in Dallas, Texas from 2009 to 2022. Univariate analyses were used to evaluate factors from initial event associated with relapsing disease course and impaired functional outcome (modified Rankin scale [mRS] >1) at final follow-up.

RESULTS

Our cohort comprised of 87 children of diverse race/ethnicity. Presentation with acute disseminated encephalomyelitis (ADEM) was more frequent in children aged ≤8 years and Caucasian background, whereas presentation with optic neuritis was more common in children aged >8 years and other race/ethnicity. 44.3 % (27/61) had relapsing disease course, of whom 48.0 % had multiple relapses. 30.3 % (23/76) had final mRS >1. Children with abnormal electroencephalogram had reduced relapse risk. Children with ADEM presentation, severe disease, low MOG-IgG titer, and central and systemic inflammation (represented by cerebrospinal fluid pleocytosis and serum leukocytosis, respectively) at onset had higher likelihood of final mRS >1.

CONCLUSION

Abnormal electroencephalogram at the first event was associated with reduced relapse risk while disease severity and peripheral inflammation significantly contributed to final neurological disability. Further studies are needed to validate these findings as early risk factors for disability and relapse and to identify optimal treatment strategies.

Less common phenotypes of myelin oligodendrocyte glycoprotein antibody-related diseases in children deserve more attention

BACKGROUND

To facilitate the identification of less common clinical phenotypes of myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) in children.

METHODS

We retrospectively reviewed medical records of 236 patients with MOGAD. The following phenotypes were considered to be typical for MOGAD: ADEM, ON, TM, and NMOSD. Less common onset clinical phenotypes were screened out; their clinical and magnetic resonance imaging (MRI), diagnosis, treatment, and prognosis were summarized and analyzed.

RESULTS

16 cases (6.8%) presented as cortical encephalitis, with convulsions, headache, and fever as the main symptoms. 15 cases were misdiagnosed in the early period. 13 cases (5.5%) showed the overlapping syndrome of MOGAD and anti-N-methyl-D aspartate receptor encephalitis (MNOS), with seizures (92.3%) being the most common clinical symptom. 11 cases (84.6%) showed relapses. The cerebral leukodystrophy-like phenotype was present in seven cases (3.0%), with a recurrence rate of 50%. Isolated seizures without any findings on MRI phenotype was present in three cases (1.3%), with the only clinical symptom being seizures of focal origin. Three cases (1.3%) of aseptic meningitis phenotype presented with prolonged fever.

CONCLUSION

40/236 (16.9%) of children with MOGAD had less common phenotypes. Less common clinical phenotypes of pediatric MOGAD are susceptible to misdiagnosis and deserve more attention.

IMPACT

This is the first comprehensive analysis and summary of all less commonl clinical phenotypes of MOGAD in children, while previous studies have only focused on a specific phenotype or case reports. We analyzed the characteristics of MOGAD in children and further revealed the reasons why these less common clinical phenotypes are prone to misdiagnosis and deserve more attention. Our research on treatment has shown that early detection of MOG antibodies and early treatment are of great significance for improving the prognosis of these patients.

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

Objective

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

Methods

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

Results

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

Conclusion

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

Clinical characteristics of Chinese pediatric patients positive for anti-NMDAR and MOG antibodies: a case series

Introduction

The cases of MOG-AD (MOG antibody-associated disorder) and anti-NMDAR encephalitis overlapping syndrome (MNOS) are rare, especially among pediatric patients, and their clinical understanding is limited. This study aimed to investigate the clinical manifestations, imaging findings, treatments, and prognosis of Chinese pediatric patients who tested positive for anti-NMDAR and MOG antibodies.

Methods

This retrospective study enrolled 10 MNOS pediatric patients, 50 MOG-AD (anti-NMDAR antibody-negative), and 81 anti-NMDAR encephalitis (MOG antibody-negative) pediatric patients who were admitted from July 2016 to June 2022 and used their clinical data for comparison.

Results

The MNOS patients had a significantly lower incidence of psycho-behavioral abnormalities and involuntary movements than anti-NMDAR antibody (+)/MOG antibody (-) patients and had a significantly higher incidence of sleep disorders, seizures, and psycho-behavioral abnormalities than MOG antibody (+)/anti-NMDAR antibody (-) patients. The MNOS patients had a significantly higher incidence of MRI abnormalities than the anti-NMDAR antibody (+)/MOG antibody (-) patients, while there was no significant difference in the incidence between the MNOS patients and the MOG antibody (+)/anti-NMDAR antibody (-) patients. No significant difference was seen in the initial mRS score between the three groups of patients. The anti-NMDAR antibody (+)/MOG antibody (-) patients had a higher rate of admission to the ICU, a longer length of in-hospital stay, and a higher rate of introduction to second-line treatment than the other two groups of patients. No significant difference was seen in the mRS score at the last follow-up and in the disease recurrence rate between the three groups. All these patients respond well to immunosuppressive therapy.

Discussion

In the presence of psycho-behavioral abnormalities, sleep disorders, and frequent seizures in MOG-AD patients or demyelinating symptoms of the central nervous system or demyelinating lesions on head MRI in anti-NMDAR encephalitis patients, the coexistence of MOG and anti-NMDAR antibodies should be considered and would suggest a diagnosis of MNOS for these patients. Immunotherapy is effective among these patients and should be given possibly earlier.

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.

Increased Intracranial Pressure in Pediatric Myelin Oligodendrocyte Glycoprotein Antibody-Associated Disease

BACKGROUND AND OBJECTIVES

Elevated intracranial pressure (ICP) in myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD) has been largely unexplored. The objectives of this study were to determine the frequency of increased ICP in MOGAD and its association with disease course and outcomes and to highlight cases requiring medical and/or surgical management of increased ICP.

METHODS

In this retrospective, single-center cohort study, we examined the clinical and paraclinical data from the initial presentation and follow-up data of children diagnosed with MOGAD. In those with opening pressure (OP) measurements, univariate analyses were used to evaluate factors associated with increased ICP, which was defined as OP > 28 cm H2O. We also present a case series of patients with or without OP measurement who required medical and/or surgical management of increased ICP.

RESULTS

Of 86 children with MOGAD, 43 (50.0%) had an OP recorded and 7 (8.1%) required ICP management. In those with OP recorded, the median (interquartile range) OP for the different MOGAD phenotypes were: 30.0 (22.8-41.6) (acute disseminated encephalomyelitis, ADEM), 20.5 (16.1-23.6) (optic neuritis), 17.0 (17.0-22.5) (myelitis), and 19.5 (16.5-29.3) (other) cm H20. Overall, 20.9% had increased ICP based on an OP > 28 cm H2O, of whom 77.8% presented with ADEM. In a subgroup analysis of those presenting with ADEM, those with an elevated ICP had longer hospital stay (p = 0.007) and neurologic disability (defined as modified Rankin Scale >1) (p = 0.049). In those with or without OP recorded, 7 (6 with ADEM, one with cerebral cortical encephalitis) required ICP-directed therapies. Findings on brain MRI in these 7 children revealed extensive disease burden with bilateral cerebral involvement and evidence of restricted diffusion. While neuropsychological data in this small subset revealed significant variability, all sustained identifiable deficits after discharge, including attention-deficit hyperactivity disorders and language and learning disorders.

DISCUSSION

In pediatric MOGAD, increased OP and ADEM at initial presentation were associated with longer hospital stays and greater long-term morbidity. Although invasive ICP monitoring has not been specifically advocated in the management of MOGAD, it is important to recognize signs and symptoms of increased ICP in these patients and consider ICP monitoring and management strategies based on clinical and radiologic findings, especially in those presenting with ADEM and with OP > 28 cm H2O.

Acquired Demyelinating Syndromes

Acquired demyelinating syndromes (ADS) are a heterogenous group of inflammatory demyelinating conditions that include presentations of optic neuritis, transverse myelitis, and acute demyelinating encephalomyelitis. They can be monophasic or can develop into relapsing episodes of the initial demyelinating event or evolve to include other types of demyelination. Significant progress has been made in differentiating subtypes of ADS that differ in their tendency to relapse and in which anti-inflammatory therapies are effective. Differentiating between these subtypes is important for the optimal management of these patients. Clinical features, labs (especially autoantibodies), and MRI findings can help to differentiate between the different ADS.

Clinical and radiographic features of a cohort of adult and pediatric subjects in the Pacific Northwest with myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD)

BACKGROUND

Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is a newly described clinical entity comprised of isolated or recurrent attacks of optic neuritis, transverse myelitis, acute disseminated encephalomyelitis (ADEM), encephalitis, or seronegative NMOSD. Prior studies report that 30-80 % of children and adults with MOGAD go on to have relapses though there are no reliable predictors. The objectives of this study were to (1) describe the demographic, clinical, and radiographic patterns of MOGAD at our center and (2) identify possible predictors of relapsing disease.

METHODS

Single-center retrospective cohort study of pediatric and adult subjects with MOGAD evaluated at least once at our center between January 1, 2017 and September 30, 2022. Eligible subjects had a history of positive MOG-IgG and consistent clinical syndrome comprised of an initial attack of optic neuritis (ON), transverse myelitis (TM), ADEM, cerebral cortical encephalitis, seronegative neuromyelitis optica (simultaneous ON and TM), isolated brainstem or cerebellar syndrome, or other (not fitting into another group). Relapsing subjects or those remaining monophasic at 12 months were included in the analyses of predictors of relapsing disease. Covariates included age, sex, race/ethnicity, and index event phenotype. Unadjusted and adjusted risk ratios were calculated for pediatric and adult subjects.

RESULTS

We describe the demographic, clinical, and radiographic characteristics of 58 subjects with MOGAD. Covariates from 48 subjects were analyzed for predictors of relapsing disease. In adults, Hispanics and non-White non-Hispanics were at increased risk of relapsing disease compared to non-Hispanic Whites [Adjusted RR 1.52 (95 % CI: 1.01, 2.30)]. There were no significant associations in the pediatric group.

CONCLUSION

This study is the first to describe a cohort of MOGAD in the Pacific Northwest. Our findings highlight racial and ethnic differences in risk of relapsing MOGAD in adults. Further studies on racial and ethnic differences in MOGAD are needed to confirm these findings.

Clinical and radiological features, treatment responses and prognosis in pediatric patients with co-existing anti-N-methyl-D-aspartate receptor and myelin oligodendrocyte glycoprotein antibody-associated encephalitis: A single center study

OBJECTIVES

To characterize the clinical and radiological features, treatment responses and outcomes of children with co-existing anti-N-methyl-D-aspartate receptor(NMDAR) and myelin oligodendrocyte glycoprotein(MOG) antibody-associated encephalitis.

METHODS

Clinical manifestations, imaging features, effectiveness of treatment and outcomes of patients who were cerebral spinal fluid(CSF)-positive for NMDAR-antibody(NMDAR-ab) and seropositive for MOG-antibody(MOG-ab) were analyzed.

RESULTS

Twelve patients including 8 females and 4 males were enrolled. The median onset age was 9 years, ranging from 2.2 to 12.8 years. Behavioral changes and/or psychiatric symptoms (n = 8/12), seizures (n = 8/12), encephalopathy (n = 7/12) were 3 of the most common symptoms. Brain magnetic resonance imaging(MRI) of all the patients showed T2/fluid attenuation inversion recovery(FLAIR) abnormal signal in the cerebral white matter at least once in the courses of disease, 2 of whom developed new brain lesions which were asymptomatic. All of the patients had supratentorial lesions. Spinal cord MRI was performed in 7 patients. Only 1 patient showed related abnormalities with increased T2 signal in the spinal cord C1-5. Nine patients underwent optic nerve MRI; 5 patients demonstrated abnormal results, among whom 4 exhibited T2 abnormal signal (2 were symptom-free) and 1 showed a little effusion in bilateral optic nerve sheats. Intravenous immunoglobulin (IVIG) and intravenous methylprednisolone (IVMP) were the most common used therapies in those patients. Nine patients were treated with second-line therapy to prevent relapses. For total 29 clinical attacks, the median modified Rankin Scale (mRS) before treatment and after therapy of acute stage was 1 and 0, respectively. Seven of 12 patients(58.3 %) experienced clinical relapses. In terms of outcome, all of the patients' mRS of last follow-up (≥6 months) was ≤2.

CONCLUSIONS

Behavioral changes and/or psychiatric symptoms, seizures and encephalopathy were common in children with co-existing anti-NMDAR and MOG antibody-associated encephalitis. A minority of subjects may develop asymptomatic lesions on brain and optic nerve MRI. The relapse rate of this disease is relatively high. The majority of patients responded well to the immunotherapies and had a good outcome(mRS of last follow-up≤2).

Diagnostic Value of Multiparameter MRI-Based Radiomics in Pediatric Myelin Oligodendrocyte Glycoprotein Antibody-Associated Disorders

BACKGROUND AND PURPOSE

Myelin oligodendrocyte glycoprotein antibody-associated disorders (MOGAD) have a higher prevalence among children. For children undergoing the initial manifestation of MOGAD, prompt diagnosis has paramount importance. This study assessed the performance of multiparameter MRI-based radiomics in distinguishing patients with and without MOGAD with idiopathic inflammatory demyelinating diseases.

MATERIALS AND METHODS

We enrolled a cohort of 121 patients diagnosed with idiopathic inflammatory demyelinating diseases, including 68 children with MOGAD and 53 children without MOGAD. Radiomics models (T1WI, T2WI, FLAIR, and compound model) using features extracted from demyelinating lesions within the brain parenchyma were developed in the training set. The performance of these models underwent validation within the internal testing set. Additionally, we gathered clinical factors and MRI features of brain parenchymal lesions at their initial presentation. Subsequently, these variables were used in the construction of a clinical prediction model through multivariate logistic regression analysis.

RESULTS

The areas under the curve for the radiomics models (T1WI, T2WI, FLAIR, and the compound model) in the training set were 0.781 (95% CI, 0.689-0.864), 0.959 (95% CI, 0.924-0.987), 0.939 (95% CI, 0.898-0.979), and 0.989 (95% CI, 0.976-0.999), respectively. The areas under the curve for the radiomics models (T1WI, T2WI, FLAIR, and the compound model) in the testing set were 0.500 (95% CI, 0.304-0.652), 0.833 (95% CI, 0.697-0.944), 0.804 (95% CI, 0.664-0.918), and 0.905 (95% CI, 0.803-0.979), respectively. The areas under the curve of the clinical prediction model in the training set and testing set were 0.700 and 0.289, respectively.

CONCLUSIONS

Multiparameter MRI-based radiomics helps distinguish MOGAD from non-MOGAD in patients with idiopathic inflammatory demyelinating diseases.

Pediatric anti-NMDAR encephalitis with demyelination on brain MRI: A single center study

OBJECTIVE

To explore the clinical characteristics, immunotherapy response, and prognosis of pediatric anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis associated with demyelination on brain magnetic resonance (MRI).

METHODS

We retrospectively reviewed the medical records of children diagnosed with anti-NMDAR encephalitis in our hospital between January 2016 and December 2021. All children with evidence of demyelination on brain MRI were included.

RESULTS

A total of 183 anti-NMDAR encephalitis children were included; 8.7 % (16/183) of them had demyelination on brain MRI. Nine were positive for myelin oligodendrocyte glycoprotein (MOG)-IgG, while two were positive for both MOG-IgG and glial fibrillary acidic protein (GFAP)-IgG. Four patients had a history of acquired demyelinating syndromes and encephalitis, respectively, while nine (56.3 %) had atypical symptoms of anti-NMDAR encephalitis. All children had supratentorial demyelination on brain MRI; four of them had additional infratentorial lesions. All children received first-line immunotherapy; four were administered repeated first-line immunotherapy and/or rituximab because of poor initial response. During the follow-up, 37.5 % (6/16) of the children relapsed, but all responded well to immunotherapy. There were no significant differences in mRS score before immunotherapy, response to first-line immunotherapy, and long-term prognosis between anti-NMDAR encephalitis children with and without demyelination. However, patients with demyelination were more likely to have a history of acquired demyelinating syndromes or unexplained cortical encephalitis and to relapse.

CONCLUSION

Pediatric anti-NMDAR encephalitis can co-occur with demyelination and has a high rate of MOG-IgG positivity. A history of acquired demyelinating syndromes or unexplained cortical encephalitis and atypical symptoms may indicate demyelination in children with anti-NMDAR encephalitis. Pediatric anti-NMDAR encephalitis with demyelination is more likely to relapse and needs a closer follow-up. However, it remains unknown whether more intensive immunotherapy is required in these patients.

Anti-Inflammatory and Immunomodulatory Effect of High-Dose Immunoglobulins in Children: From Approved Indications to Off-Label Use

BACKGROUND

The large-scale utilization of immunoglobulins in patients with inborn errors of immunity (IEIs) since 1952 prompted the discovery of their key role at high doses as immunomodulatory and anti-inflammatory therapy, in the treatment of IEI-related immune dysregulation disorders, according to labelled and off-label indications. Recent years have been dominated by a progressive imbalance between the gradual but constant increase in the use of immunoglobulins and their availability, exacerbated by the SARS-CoV-2 pandemic.

OBJECTIVES

To provide pragmatic indications for a need-based application of high-dose immunoglobulins in the pediatric context.

SOURCES

A literature search was performed using PubMed, from inception until 1st August 2023, including the following keywords: anti-inflammatory; children; high dose gammaglobulin; high dose immunoglobulin; immune dysregulation; immunomodulation; immunomodulatory; inflammation; intravenous gammaglobulin; intravenous immunoglobulin; off-label; pediatric; subcutaneous gammaglobulin; subcutaneous immunoglobulin. All article types were considered.

IMPLICATIONS

In the light of the current imbalance between gammaglobulins' demand and availability, this review advocates the urgency of a more conscious utilization of this medical product, giving indications about benefits, risks, cost-effectiveness, and administration routes of high-dose immunoglobulins in children with hematologic, neurologic, and inflammatory immune dysregulation disorders, prompting further research towards a responsible employment of gammaglobulins and improving the therapeutical decisional process.

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.

Phenotypic characteristics of myelin oligodendrocyte glycoprotein antibody-associated disease in children: a single-center, retrospective study

Objective

To analyze the clinical characteristics and follow-up data of children with different clinical phenotypes of myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD).

Methods

The basic demographic and clinical features, laboratory and imaging examination results, and follow-up data of 74 Chinese children with different phenotypes of MOGAD were retrospectively reviewed and analyzed.

Results

The male-to-female ratio in this cohort was 1:1.39. The clinical phenotypes of MOGAD included acute disseminated encephalomyelitis (ADEM; n = 37), encephalitis (n = 11), optic neuritis (ON, n = 9), neuromyelitis optica spectrum disorder (NMOSD; n = 9), transverse myelitis (TM; n = 6), leukodystrophy-like manifestations (n = 1), and meningitis (n = 1). The mean age of disease onset was 86 months. The number of leukocytes in the cerebrospinal fluid of patients with ADEM was significantly higher than that in patients with ON but lower than that in patients with TM (p < 0.05). The pathogen detection rate among all patients was 36.5%. Recurrence occurred in 17 patients (23%), with the highest recurrence rate in patients with NMOSD and TM. Patients with recurrence had a significantly higher median age than those without any recurrence (109.00 vs. 82.44 months, p < 0.05). The male-to-female ratio in patients with recurrence was 1:4.67, which differed significantly from that at first onset (p < 0.05).

Conclusion

The most common clinical phenotypes of MOGAD in this cohort were ADEM and encephalitis. Recurrence of MOGAD may be related to age and sex, with a higher recurrence rate observed in females. These findings provide a basis for further exploration of the characteristics of different MOGAD phenotypes.

Pathophysiology, diagnosis, and management of neuroinflammation in covid-19

Although neurological complications of SARS-CoV-2 infection are relatively rare, their potential long term morbidity and mortality have a significant impact, given the large numbers of infected patients. Covid-19 is now in the differential diagnosis of a number of common neurological syndromes including encephalopathy, encephalitis, acute demyelinating encephalomyelitis, stroke, and Guillain-Barré syndrome. Physicians should be aware of the pathophysiology underlying these presentations to diagnose and treat patients rapidly and appropriately. Although good evidence has been found for neurovirulence, the neuroinvasive and neurotropic potential of SARS-CoV-2 is limited. The pathophysiology of most complications is immune mediated and vascular, or both. A significant proportion of patients have developed long covid, which can include neuropsychiatric presentations. The mechanisms of long covid remain unclear. The longer term consequences of infection with covid-19 on the brain, particularly in terms of neurodegeneration, will only become apparent with time and long term follow-up.

Myelin oligodendrocyte glycoprotein antibody-associated disease as a novel presentation of central nervous system autoimmunity in a pediatric patient with Wiskott-Aldrich syndrome

BACKGROUND

Wiskott-Aldrich syndrome (WAS) is an X-linked primary immunodeficiency caused by mutations in the WAS gene that leads to increased susceptibility to infections, thrombocytopenia, eczema, malignancies, and autoimmunity. Central nervous system (CNS) autoimmune manifestations are uncommon.

CASE PRESENTATION

We describe the case of a five-year-old boy with refractory thrombocytopenia and iron deficiency anemia who developed relapsing bilateral optic neuritis. Myelin oligodendrocyte glycoprotein antibody (MOG-IgG) via serum fluorescence-activated cell sorting assay was positive (titer 1:100), confirming a diagnosis of myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD). At age six, molecular panel testing for genes associated with primary immunodeficiency identified a missense WAS gene variant. He was subsequently found to have decreased WAS protein expression, consistent with a diagnosis of WAS.

CONCLUSIONS

This case expands the reported spectrum of CNS autoimmunity associated with WAS and may help to inform long-term therapeutic options.

Acquired Demyelinating Syndromes of the Central Nervous System in Children: The Importance of Regular Follow-up in the First Year After Onset

AIM

We reviewed the clinical features of a sample of pediatric acquired demyelinating syndromes with the purpose of determining the appropriate protocol for follow-up after the first episode.

METHODS

A multicenter retrospective observational study was conducted on a cohort of 40 children diagnosed with a first episode of acquired demyelinating syndrome over the period 2012-2021. Patients were evaluated with clinical and neuroradiologic assessment after 3, 6, and 12 months, with a median follow-up of 4.0 years.

RESULTS

At the first acquired demyelinating syndrome episode, 18 patients (45%) were diagnosed with acute disseminated encephalomyelitis, 18 (45%) with clinical isolated syndrome, and 4 (10%) with multiple sclerosis. By month 12, 12 patients (30%) had progressed from an initial diagnosis of acute disseminated encephalomyelitis (2) or clinical isolated syndrome (10) to multiple sclerosis. Of these, 6 had clinical relapse and 6 radiologic relapse only. The first relapse occurred after a median of 3 months. Among the patients who had evolved toward multiple sclerosis, there was a prevalence of females (P = .014), higher oligoclonal bands positivity (P = .009), and older median age (P < .001) as compared with those who had remained stable.

INTERPRETATION

Both clinical and radiologic follow-up of children with acquired demyelinating syndromes is crucial, especially during the first year after acute onset, for early identification of multiple sclerosis and prompt initiation of disease-modifying treatment to delay axonal damage and to limit disability.

Deviation From Normative Whole Brain and Deep Gray Matter Growth in Children With MOGAD, MS, and Monophasic Seronegative Demyelination

BACKGROUND AND OBJECTIVES

Pediatric-acquired demyelination of the CNS associated with antibodies directed against myelin oligodendrocyte glycoprotein (MOG; MOG antibody-associated disease [MOGAD]) occurs as a monophasic or relapsing disease and with variable but often extensive T2 lesions in the brain. The impact of MOGAD on brain growth during maturation is unknown. We quantified the effect of pediatric MOGAD on brain growth trajectories and compared this with the growth trajectories of age-matched and sex-matched healthy children and children with multiple sclerosis (MS, a chronic relapsing disease known to lead to failure of normal brain growth and to loss of brain volume) and monophasic seronegative demyelination.

METHODS

We included children enrolled at incident attack in the prospective longitudinal Canadian Pediatric Demyelinating Disease Study who were recruited at the 3 largest enrollment sites, underwent research brain MRI scans, and were tested for serum MOG-IgG. Children seropositive for MOG-IgG were diagnosed with MOGAD. MS was diagnosed per the 2017 McDonald criteria. Monophasic seronegative demyelination was confirmed in children with no clinical or MRI evidence of recurrent demyelination and negative results for MOG-IgG and aquaporin-4-IgG. Whole and regional brain volumes were computed through symmetric nonlinear registration to templates. We computed age-normalized and sex-normalized z scores for brain volume using a normative dataset of 813 brain MRI scans obtained from typically developing children and used mixed-effect models to assess potential deviation from brain growth trajectories.

RESULTS

We assessed brain volumes of 46 children with MOGAD, 26 with MS, and 51 with monophasic seronegative demyelinating syndrome. Children with MOGAD exhibited delayed (p < 0.001) age-expected and sex-expected growth of thalamus, caudate, and globus pallidus, normalized for the whole brain volume. Divergence from expected growth was particularly pronounced in the first year postonset and was detected even in children with monophasic MOGAD. Thalamic volume abnormalities were less pronounced in children with MOGAD compared with those in children with MS.

DISCUSSION

The onset of MOGAD during childhood adversely affects the expected trajectory of growth of deep gray matter structures, with accelerated changes in the months after an acute attack. Further studies are required to better determine the relative impact of monophasic vs relapsing MOGAD and whether relapsing MOGAD with attacks isolated to the optic nerves or spinal cord affects brain volume over time.

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.

Subclinical optic neuritis in pediatric myelin oligodendrocyte glycoprotein antibody-associated disease

BACKGROUND AND OBJECTIVES

The clinical spectrum of myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD) is heterogenous and has evolved over time since the commercial availability of the anti-MOG antibody assay. Subclinical disease activity has been previously reported in the visual pathway, but prevalence data remains limited. We investigated subclinical optic neuritis (ON) based on changes on retinal nerve fiber layer (RNFL) thickness on optic coherence tomography (OCT) in pediatric patients who tested positive for the anti-MOG antibody.

METHODS

In this retrospective, single-center cohort study, we examined children with MOGAD with at least one complete assessment of the anterior visual pathway. Subclinical ON was defined by structural visual system disease in the absence of a subjective complaint of vision loss, pain (particularly with eye movement), or color desaturation.

RESULTS

Records were reviewed from 85 children with MOGAD, 67 of whom (78.8%) had complete records for review. Eleven children (16.4%) had subclinical ON on OCT. Ten had significant reductions in RNFL, of which one had two distinct episodes of decreased RNFL, and one had significant elevations in RNFL. Of the eleven children with subclinical ON, six (54.5%) had a relapsing disease course. We also highlighted the clinical course of three children with subclinical ON detected on longitudinal OCT, including two who had subclinical ON outside of clinical relapses.

CONCLUSION

Children with MOGAD can have subclinical ON events that can manifest as significant reductions or elevations in RNFL on OCT. OCT should be used routinely in the management and monitoring of MOGAD patients.

Clinical, radiological, therapeutic and prognostic differences between MOG-seropositive and MOG-seronegative pediatric acute disseminated encephalomyelitis patients: a retrospective cohort study

Objective

This study aimed to compare the clinical, radiological, therapeutic, and prognostic differences between pediatric patients showing acute disseminated encephalomyelitis (ADEM) with and without myelin oligodendrocyte glycoprotein (MOG) antibodies.

Methods

We retrospectively collected all available data of children diagnosed with ADEM and tested for serum MOG antibodies at the Children's Hospital of Chongqing Medical University from January 2017 to May 2021.

Results

A total of 62 patients were included in our cohort, of which 35 were MOG-seropositive and 27 were MOG-seronegative. MOG-seropositive ADEM children presented with significantly lower rates of seizures (P = 0.038) and cranial nerve (III-XII) palsy (P = 0.003). Isolated leukocytosis in the blood was more common in ADEM children with MOG antibodies (P < 0.001). The two groups showed no significant differences in the distributions and extent of the MRI lesions as well as the appearance of typical/atypical magnetic resonance imaging (MRI) features. MOG-seropositive children were more likely to relapse (P = 0.017) despite having slower oral prednisolone tapering after acute treatments (P = 0.028). In scoring performed on the basis of two neurological function scoring systems, MOG-seropositive children showed milder neurological disability status at onset (P = 0.017 and 0.025, respectively) but showed no difference during follow-up.

Conclusion

In summary, the differences in the clinical manifestations and auxiliary examination findings for MOG-seropositive and MOG-seronegative ADEM children lacked significance and specificity, making early identification difficult. MOG-seropositive children were more likely to relapse and showed slower steroid tapering. Moreover, MOG-seronegative children tended to have more severe neurological impairments at onset with no difference during follow-up.

Paediatric MOG-antibody disease presenting with intracranial hypertension and unilateral vision loss without radiological evidence of optic neuritis

Intracranial hypertension (IH) is poorly described in paediatric myelin oligodendrocyte glycoprotein antibody disease (MOGAD). We describe a unique case of seropositive MOGAD in an obese 13-year-old boy who presented with an isolated IH, bilateral optic disc swelling and sudden-onset complete vision loss in one eye without radiological evidence of optic nerve involvement. Treatment with intravenous methylprednisolone combined with an emergency shunt fully restored vision and resolved the optic disc swelling. This report adds to the growing body of evidence suggesting that obese children presenting with isolated IH should be investigated for MOGAD, and the importance of managing IH during MOGAD.

Clinical features of the first attack with leukodystrophy‐like phenotype in children with myelin oligodendrocyte glycoprotein antibody‐associated disorders

BACKGROUND

Myelin oligodendrocyte glycoprotein antibody-associated disorders (MOGAD) is identified autoimmune disorder with a predominance in paediatric patients, and the disease spectrum has expanded with clinical and radiological patterns. The aim of the study was to describe the clinical characteristics of the first attack with leukodystrophy-like phenotype with MOGAD in children.

METHODS

Patients hospitalized at the Children's Hospital of Chongqing Medical University from June 2017 to October 2021 with positive MOG antibodies and phenotype of leukodystrophy-like (symmetric white matter lesions) were retrospectively analyzed. Cell-based assays (CBAs) were used to test MOG antibodies.

RESULTS

Four cases from 143 MOGAD patients were recruited, with two females and two males. The age of onset is all under 6 years old. At the last follow-up, four cases exhibited a monophasic course, including ADEM in three patients and encephalitis in one patient. The mean EDSS score at onset was 4.62 ± 2.93, and the modified Rankin score (mRS) was 3.00 ± 1.82. First-attack symptoms include fever, headache, vomiting, seizure, loss of consciousness, emotional and behavioural disorder, and ataxia. The brain MRI showed prominent extensive and essentially symmetric distribution lesions in the white matter. All patients showed clinical and partial radiological improvement after intravenous immunoglobulin and/or glucocorticoid treatment.

CONCLUSION

The first attack with MOGAD onset of leukodystrophy-like phenotype was more frequently seen in younger children than other phenotype patients. The patients may show impressive neurologic disorders, but most patients who receive immunotherapy have a good prognosis.

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 analysis of 173 pediatric patients with antibody-mediated autoimmune diseases of the central nervous system: a single-center cohort study

Background

Antibody-mediated disorders of the central nervous system (CNS) have seen a gradual rise in their incidence and prevalence. This retrospective observational study aimed to investigate the clinical characteristics and short-term prognosis of children with antibody-mediated CNS autoimmune diseases at Hunan Children's Hospital.

Methods

We collected the clinical data of 173 pediatric patients diagnosed with antibody-mediated CNS autoimmune diseases between June 2014 and June 2021 and analyzed their demographics, clinical features, imaging and laboratory data, treatment, and prognosis.

Results

A total of 187 patients tested positive for anti-neural antibodies and 173 patients were finally diagnosed with antibody-mediated CNS autoimmune diseases after excluding the 14 false-positive cases through clinical phenotypic evaluation and follow-up of treatment outcomes. Of the 173 confirmed patients, 97 (56.06%) were positive for anti-NMDA-receptor antibody, 48 (27.75%) for anti-MOG antibody, 30 (17.34%) for anti-GFAP antibody, 5 (2.89%) for anti-CASPR2 antibody, 3 (1.73%) for anti-AQP4 antibody, 2 (1.16%) for anti-GABABR antibody, and 1 (0.58%) for anti-LGI1antibody. Anti-NMDAR encephalitis was the most commonly seen among the patients, followed by MOG antibody-associated disorders and autoimmune GFAP astrocytopathy. Psycho-behavioral abnormalities, seizures, involuntary movements, and speech disorder were the most common clinical presentations of anti-NMDAR encephalitis, while fever, headache, and disturbance of consciousness or vision were the most seen among patients with MOG antibody-associated disorders or autoimmune GFAP astrocytopathy. The coexistence of multiple anti-neural antibodies was detected in 13 patients, among which 6 cases had coexistent anti-NMDAR and anti-MOG antibodies (including 1 case with anti-GFAP antibody also), 3 cases had coexistent anti-NMDAR and anti-GFAP antibodies, 3 cases had coexistent anti-MOG and anti-GFAP antibodies, 1 case had coexistent anti-NMDAR and anti-CASPR2 antibodies, and 1 case had coexistent anti-GABABR and anti-CASPR2 antibodies. All the survivors were followed up for at least 12 months; 137 recovered completely, 33 had varying sequelae, and 3 died; 22 had one or more relapses.

Conclusion

Antibody-mediated CNS autoimmune diseases occur in children of all ages. Most such pediatric patients have a good response to immunotherapy. Despite the low mortality rate, some survivors have a non-negligible risk of developing relapses.

Frequency of myelin oligodendrocyte glycoprotein antibodies in pediatric onset multiple sclerosis

BACKGROUND

Myelin oligodendrocyte glycoprotein antibodies (MOG-Ab) are associated with acute demyelinating syndromes and only rarely detected in multiple sclerosis (MS). As MOG-Ab associated disease is common in childhood, we speculated young patients might be more likely to produce MOG-Ab and investigated the frequency of MOG-Ab seropositivity in pediatric onset MS (POMS).

MATERIAL AND METHODS

Patients who experienced their first acute demyelinating event before age 18 years and were diagnosed with MS during follow-up were included in this single-center study. Patient data were retrieved from clinical records. Serum samples obtained and frozen at clinical visits were analyzed for MOG-Ab by a live cell-based assay (CBA) measuring delta mean fluorescence intensity (MFI) and MFI ratio. The control group consisted of patients referred to pediatric neurology for headache or vertigo and who had no neurological disorder (n = 48). Another control group consisted of patients with systemic inflammatory disorders systemic lupus erythematosus (n = 17) and juvenile idiopathic arthritis (n = 13) diagnosed in the rheumatology clinic.

RESULTS

The patient group (n = 122, F/M: 90/32, mean age 17.8 ± 2.6 years) were initially diagnosed as: MS, 62/122 (50.8%), clinically isolated syndrome, 43/122 (35.2%), radiologically isolated syndrome, 9/122 (7.3%), and acute disseminated encephalomyelitis 8/122 (6.5%). All received the final diagnosis of POMS. Serum was sampled 22.4 ± 29.2 (0-132) months after the first episode. None of the control groups had MOG-Ab positivity while 2/122 (1.6%) POMS cases had MOG-Abs, and a third patient had positive MFI and a MFI ratio slightly below the cut-off. These three patients' initial and final diagnoses were MS, their annualized relapsing rates (ARRs) were 0.4-0.6, and most recent Expanded Disability Status Scale was 0.

CONCLUSION

Low titers of MOG-Ab can be detected in a small number of POMS patients at similar frequency with adult MS. Our POMS cases with MOG-Abs presented brainstem-cerebellar findings or seizures and had low ARR. Further series and longer follow-up will define whether these cases differ significantly from MOG-Ab negative POMS cases.

Clinical characteristics of myelin-oligodendrocyte glycoprotein antibody-positive pediatric autoimmune encephalitis without demyelination: A case series

Purpose

To facilitate the identification of myelin-oligodendrocyte glycoprotein (MOG) antibody-associated diseases in pediatric autoimmune encephalitis without demyelination, we explored the clinical characteristics of patients having MOG antibody-positive pediatric autoimmune encephalitis without demyelination in Children's Hospital of Chongqing Medical University, China.

Methods

We reviewed patients' medical records from January 2019 to June 2022 and retrospectively analyzed clinical manifestations, brain magnetic resonance imaging (MRI) findings, laboratory findings, treatments and outcomes of children with autoimmune encephalitis who tested positive for MOG antibodies in serum but for whom demyelination was not detected on MRI.

Results

Eighteen patients (6 boys, 12 girls; median age: 103.2 (range: 36-160) months) were included: 15 tested positive for MOG antibodies in both serum and cerebrospinal fluid (CSF); three tested positive only in serum. The most common clinical symptoms were altered mental status (18/18), fever (16/18), headache (14/18), seizures (6/18) and focal neurologic deficits (5/18). All patients had CSF pleocytosis (median count: 74/µL, range: 14-380/µL); five patients had elevated CSF protein levels (median: 0.85 g/L, range: 0.53-1.48 g/L) simultaneously. CSF glucose levels were normal in all patients. Abnormal electroencephalogram (EEG) results were found in 12 patients: generalized or focal slowing (9/12), focal epileptic discharges (2/12), and generalized slowing and focal epileptic discharges (1/12). Twelve of the 18 patients showed hyperintense T2-weighted lesions on brain MRI in the cortex (6), basal ganglia (5), thalamus (3), cerebellum (4), and brainstem (2). All patients received immunotherapy and had favorable outcomes at discharge (modified Rankin scale score: <2). Three children relapsed once; however, all children had good outcomes at the last follow-up.

Conclusion

MOG antibody-positive pediatric autoimmune encephalitis without demyelination is mainly characterized by prolonged fever, altered mental status, headache, mild-to-moderate increase in cell count in the CSF, and normal or abnormal brain MRI, which may involve any part outside the white matter without specificity. All patients with MOG antibody-positive pediatric autoimmune encephalitis without demyelination had favorable outcomes after immunotherapy, while a few patients relapsed once.

Early Immunotherapy and Longer Corticosteroid Treatment Are Associated With Lower Risk of Relapsing Disease Course in Pediatric MOGAD

BACKGROUND AND OBJECTIVES

We sought to identify early factors associated with relapse and outcome in paediatric-onset myelin oligodendrocyte glycoprotein antibody-associated disorders (MOGAD).

METHODS

In a multicenter retrospective cohort of pediatric MOGAD (≤18 years), onset features and treatment were compared in patients with monophasic vs relapsing disease (including cases with follow-up ≥12 months after onset or relapse at any time) and in patients with final Expanded Disability Status Scale (EDSS) 0 vs ≥1 at last follow-up (including cases with follow-up >3 months after last event or EDSS0 at any time). Multivariable logistic regression models were used to evaluate factors associated with relapsing disease course and EDSS ≥ 1 at final follow-up.

RESULTS

Seventy-five children were included (median onset age 7 years; median 30 months of follow-up). Presentation with acute disseminated encephalomyelitis was more frequent in children aged 8 years or younger (66.7%, 28/42) than in older patients (30.3%, 10/33) (p = 0.002), whereas presentation with optic neuritis was more common in children older than 8 years (57.6%, 19/33) than in younger patients (21.4%, 9/42) (p = 0.001). 40.0% (26/65) of patients relapsed. Time to first relapse was longer in children aged 8 years or younger than in older patients (median 18 vs 4 months) (p = 0.013). Factors at first event independently associated with lower risk of relapsing disease course were immunotherapy <7 days from onset (6.7-fold reduced odds of relapsing course, OR 0.15, 95% CI 0.03-0.61, p = 0.009), corticosteroid treatment for ≥5 weeks (6.7-fold reduced odds of relapse, OR 0.15, 95% CI 0.03-0.80, p = 0.026), and abnormal optic nerves on onset MRI (12.5-fold reduced odds of relapse, OR 0.08, 95% CI 0.01-0.50, p = 0.007). 21.1% (15/71) had EDSS ≥ 1 at final follow-up. Patients with a relapsing course had a higher proportion of final EDSS ≥ 1 (37.5%, 9/24) than children with monophasic disease (12.8%, 5/39) (p = 0.022, univariate analysis). Each 1-point increment in worst EDSS at onset was independently associated with 6.7-fold increased odds of final EDSS ≥ 1 (OR 6.65, 95% CI 1.33-33.26, p = 0.021).

DISCUSSION

At first attack of pediatric MOGAD, early immunotherapy, longer duration of corticosteroid treatment, and abnormal optic nerves on MRI seem associated with lower risk of relapse, whereas higher disease severity is associated with greater risk of final disability (EDSS ≥ 1).

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.

Myelin oligodendrocyte glycoprotein-associated disease is associated with BANK1, RNASET2 and TNIP1 polymorphisms

AIM

Here we aimed to compare association of common immune-related genetic variants with three autoimmune central nervous system (CNS) demyelinating diseases, namely myelin oligodendrocyte glycoprotein-associated disease (MOGAD), multiple sclerosis (MS) and neuromyelitis optica spectrum disorder (NMOSD).

METHODS

In this retrospective cross-sectional study, 26 common immune-related single nucleotide polymorphisms were genotyped in 102 patients with MOGAD, 100 patients with MS, 198 patients with NMOSD and 541 healthy control subjects recruited from Guangzhou, China.

RESULTS

Among all tested genetic variations, one polymorphism, B cell scaffold protein with ankyrin repeats 1 (BANK1) rs4522865 was associated with multiple disorders, namely MOGAD (OR = 1.94, 95% CI:1.19-3.17, P = 0.0059) and NMOSD (OR = 1.69, 95% CI:1.17-2.45). Besides BANK1 rs4522865, two other non-HLA loci, ribonuclease T2 (RNASET2) rs9355610 (OR = 0.47, 95% CI: 0.26-0.85) and TNFAIP3 interacting protein 1 (TNIP1) rs10036748 (OR = 1.76, 95% CI: 1.16-2.71), were associated with MOGAD. In addition, NMOSD was associated with signal transducer and activator of transcription 4 (STAT4) rs7574865 (OR = 1.58, 95% CI: 1.12-2.24) and general transcription factor Iii (GTF2I) rs73366469 (OR = 1.60, 95% CI:1.12-2.29), while MS was associated with a killer cell lectin like receptor G1 (KLRG1) rs1805673 (OR = 0.61, 95% CI: 0.40-0.94) and T-box transcription factor 21 (TBX21) rs17244587 (OR = 2.25, 95% CI: 1.25-4.06).

CONCLUSION

The current study suggests for the first time three non-HLA susceptibility loci for MOGAD. In addition, comparison of association of 26 immune-related polymorphisms with three autoimmune CNS demyelinating diseases demonstrates substantial difference in genetic basis of those disorders.

Clinical characteristics and associated factors of pediatric acute disseminated encephalomyelitis patients with MOG antibodies: a retrospective study in Hangzhou, China

Background

To explore the clinical characteristics and related factors of children with acute disseminated encephalomyelitis (ADEM) with positive anti-myelin oligodendrocyte glycoprotein (MOG) antibody.

Methods

A retrospective study was conducted and enrolled pediatric ADEM patients who underwent serum MOG antibody detection from May 2017 to August 2020. The patients were divided into two groups: MOG- immunoglobulin G (IgG) positive (n = 35) and MOG-IgG negative (n = 50). We analyzed the clinical characteristics of MOG-IgG-positive ADEM pediatric patients and conducted a comparative analysis between the two groups.

Results

Thirty-five patients (21 males and 14 females) in the MOG-IgG-positive group with encephalopathy, multifocal neurological symptoms, and typical magnetic resonance imaging (MRI) abnormalities were enrolled. They usually had a favorable outcome, while some suffered from relapse. Compared to the MOG-IgG-negative group, MOG-IgG-positive ADEM patients had a longer disease duration (median: 10 vs. 6 days), more meningeal involvement (31.4% vs. 8%) and frontal lobe involvement (82.8% vs. 68%), higher relapse rates (14.3% vs. 2%), lower serum tumor necrosis factor (1–12.4 pg/ml, median 1.7 vs. 1–34 pg/ml, median 2.2) and interferon-gamma (1–9.4 pg/ml, median 1.3 vs. 1–64 pg/ml, median 3) (P < 0.05, respectively). Multivariate logistic regression analysis showed that the longer disease duration, meningeal involvement and frontal lobe involvement were the correlated factors of patients with ADEM with MOG antibody (P < 0.05).

Conclusions

Our findings provide clinical evidence that MOG-IgG positivity is associated with longer disease duration, meningeal involvement, and frontal lobe involvement.

Epidemiology of acute flaccid myelitis in children in the Netherlands, 2014 to 2019

Background

Acute flaccid myelitis (AFM) is a polio-like condition affecting mainly children and involving the central nervous system (CNS). AFM has been associated with different non-polio-enteroviruses (EVs), in particular EV-D68 and EV-A71. Reliable incidence rates in European countries are not available.

Aim

To report AFM incidence in children in the Netherlands and its occurrence relative to EV-D68 and EV-A71 detections.

Methods

In 10 Dutch hospitals, we reviewed electronic health records of patients diagnosed with a clinical syndrome including limb weakness and/or CNS infection and who were < 18 years old when symptoms started. After excluding those with a clear alternative diagnosis to AFM, those without weakness, and removing duplicate records, only patients diagnosed in January 2014–December 2019 were retained and further classified according to current diagnostic criteria. Incidence rates were based on definite and probable AFM cases. Cases’ occurrences during the study period were co-examined with laboratory-surveillance detections of EV-D68 and EV-A71.

Results

Among 143 patients included, eight were classified as definite and three as probable AFM. AFM mean incidence rate was 0.06/100,000 children/year (95% CI: −0.03 to 0.14). All patient samples were negative for EV-A71. Of respiratory samples in seven patients, five were EV-D68 positive. AFM cases clustered in periods with increased EV-D68 and EV-A71 detections.

Conclusions

AFM is rare in children in the Netherlands. The temporal coincidence of EV-D68 circulation and AFM and the detection of this virus in several cases’ samples support its association with AFM. Increased AFM awareness among clinicians, adequate diagnostics and case registration matter to monitor the incidence.

Temporal Dynamics of MOG Antibodies in Children With Acquired Demyelinating Syndrome

Background and Objective

The spectrum of myelin oligodendrocyte glycoprotein (MOG) antibody–associated disorder (MOGAD) comprises monophasic diseases such as acute disseminated encephalomyelitis (ADEM), optic neuritis (ON), and transverse myelitis and relapsing courses of these presentations. Persistently high MOG antibodies (MOG immunoglobulin G [IgG]) are found in patients with a relapsing disease course. Prognostic factors to determine the clinical course of children with a first MOGAD are still lacking. The objective of the study is to assess the clinical and laboratory prognostic parameters for a risk of relapse and the temporal dynamics of MOG‐IgG titers in children with MOGAD in correlation with clinical presentation and disease course.

Methods

In this prospective multicenter hospital-based study, children with a first demyelinating attack and complete data set comprising clinical and radiologic findings, MOG-IgG titer at onset, and clinical and serologic follow-up data were included. Serum samples were analyzed by live cell-based assay, and a titer level of ≥1:160 was classified as MOG-IgG–positive.

Results

One hundred sixteen children (f:m = 57:59) with MOGAD were included and initially diagnosed with ADEM (n = 59), unilateral ON (n = 12), bilateral ON (n = 16), myelitis (n = 6), neuromyelitis optica spectrum disorder (n = 8) or encephalitis (n = 6). The median follow-up time was 3 years in monophasic and 5 years in relapsing patients. There was no significant association between disease course and MOG-IgG titers at onset, sex, age at presentation, or clinical phenotype. Seroconversion to MOG-IgG–negative within 2 years of the initial event showed a significant risk reduction for a relapsing disease course. Forty-two/one hundred sixteen patients (monophasic n = 26, relapsing n = 16) had serial MOG-IgG testing in years 1 and 2 after the initial event. In contrast to relapsing patients, monophasic patients showed a significant decrease of MOG-IgG titers during the first and second years, often with seroconversion to negative titers. During the follow-up, MOG-IgG titers were persistently higher in relapsing than in monophasic patients. Decrease in MOG-IgG of ≥3 dilution steps after the first and second years was shown to be associated with a decreased risk of relapses. In our cohort, no patient experienced a relapse after seroconversion to MOG-IgG–negative.

Discussion

In this study, patients with declining MOG-IgG titers, particularly those with seroconversion to MOG-IgG–negative, are shown to have a significantly reduced relapse risk.

Sex and gender differences in autoimmune demyelinating CNS disorders: Multiple sclerosis (MS), neuromyelitis optica spectrum disorder (NMOSD) and myelin-oligodendrocyte-glycoprotein antibody associated disorder (MOGAD)

Multiple sclerosis (MS), Neuromyelitis optica spectrum disorder (NMOSD) and Myelin-Oligodendrocyte-Glycoprotein antibody associated disorder (MOGAD) are demyelinating disorders of the central nervous system (CNS) of autoimmune origin. Here, we summarize general considerations on sex-specific differences in the immunopathogenesis and hormonal influences as well as key clinical and epidemiological elements. Gender-specific issues are widely neglected starting with the lacking separation of sex as a biological variable and gender comprising the sociocultural components. As for other autoimmune diseases, female preponderance is common in MS and NMOSD. However, sex distribution in MOGAD seems equal. As in MS, immunotherapy in NMOSD and MOGAD is crucial to prevent further disease activity. Therefore, we assessed data on sex differences of the currently licensed disease-modifying treatments for efficacy and safety. This topic seems widely neglected with only fragmented information resulting from post-hoc analyses of clinical trials or real-world post-marketing studies afflicted with lacking power and/or inherent sources of bias. In summary, biological hypotheses of sex differences including genetic factors, the constitution of the immune system and hormonal influences are based upon human and preclinical data, especially for the paradigmatic disease of MS whereas specific data for NMOSD and MOGAD are widely lacking. Epidemiological and clinical differences between men and women are well described for MS and to some extent for NMOSD, yet, with remaining contradictory findings. MOGAD needs further detailed investigation. Sex-specific analyses of safety and efficacy of long-term immunotherapies need to be addressed in future studies designed and powered to answer the pressing questions and to optimize and individualize treatment.

Pediatric Acquired Demyelinating Disorders

PURPOSE OF REVIEW

This article reviews the clinical presentation, diagnostic evaluation, treatment, and prognosis of the most common monophasic and relapsing acquired demyelinating disorders presenting in childhood.

RECENT FINDINGS

Our understanding of neuroimmune disorders of the central nervous system is rapidly expanding. Several clinical and paraclinical factors help to inform the diagnosis and ultimately the suspicion for a monophasic versus relapsing course, including the age of the patient (prepubertal versus postpubertal), presence or absence of clinical encephalopathy, identification of serum autoantibodies (eg, myelin oligodendrocyte glycoprotein [MOG] and aquaporin-4), presence of intrathecally unique oligoclonal bands, and location/extent of radiologic abnormalities. Collaborative international research efforts have facilitated understanding of the safety and efficacy of currently available immunotherapies in children with acquired demyelinating disorders, particularly multiple sclerosis.

SUMMARY

Although many of the demyelinating disorders presented in this article can affect children and adults across the age spectrum, the clinical and radiologic phenotypes, treatment considerations, and long-term prognoses are often distinct in children.

Characteristic retinal atrophy pattern allows differentiation between pediatric MOGAD and MS after a single optic neuritis episode

Background

Optic neuritis (ON) is the most prevalent manifestation of pediatric multiple sclerosis (MS^ped) and myelin-oligodendrocyte glycoprotein antibody-associated disease (MOGAD^ped) in children > 6 years. In this study, we investigated retinal atrophy patterns and diagnostic accuracy of optical coherence tomography (OCT) in differentiating between both diseases after the first ON episode.

Methods

Patients were retrospectively identified in eight tertial referral centers. OCT, VEP and high/low-contrast visual acuity (HCVA/LCVA) have been investigated > 6 months after the first ON. Prevalence of pathological OCT findings was identified based on data of 144 age-matched healthy controls.

Results

Thirteen MOGAD^ped (10.7 ± 4.2 years, F:M 8:5, 21 ON eyes) and 21 MS^ped (14.3 ± 2.4 years, F:M 19:2, 24 ON eyes) patients were recruited. We observed a significantly more profound atrophy of both peripapillary and macular retinal nerve fiber layer in MOGAD^ped compared to MS^ped (pRNFL global: 68.2 ± 16.9 vs. 89.4 ± 12.3 µm, p < 0.001; mRNFL: 0.12 ± 0.01 vs. 0.14 ± 0.01 mm³, p < 0.001). Neither other macular layers nor P100 latency differed. MOGAD^ped developed global atrophy affecting all peripapillary segments, while MS^ped displayed predominantly temporal thinning. Nasal pRNFL allowed differentiation between both diseases with the highest diagnostic accuracy (AUC = 0.902, cutoff < 62.5 µm, 90.5% sensitivity and 70.8% specificity for MOGAD^ped). OCT was also substantially more sensitive compared to VEP in identification of ON eyes in MOGAD (pathological findings in 90% vs. 14%, p = 0.016).

Conclusion

First MOGAD-ON results in a more severe global peripapillary atrophy compared to predominantly temporal thinning in MS-ON. Nasal pRNFL allows differentiation between both diseases with the highest accuracy, supporting the additional diagnostic value of OCT in children with ON.

Neuroimaging in cerebellar ataxia in childhood: A review

Ataxia is one of the most common pediatric movement disorders and can be caused by a large number of congenital and acquired diseases affecting the cerebellum or the vestibular or sensory system. It is mainly characterized by gait abnormalities, dysmetria, intention tremor, dysdiadochokinesia, dysarthria, and nystagmus. In young children, ataxia may manifest as the inability or refusal to walk. The diagnostic approach begins with a careful clinical history including the temporal evolution of ataxia and the inquiry of additional symptoms, is followed by a meticulous physical examination, and, depending on the results, is complemented by laboratory assays, electroencephalography, nerve conduction velocity, lumbar puncture, toxicology screening, genetic testing, and neuroimaging. Neuroimaging plays a pivotal role in either providing the final diagnosis, narrowing the differential diagnosis, or planning targeted further workup. In this review, we will focus on the most common form of ataxia in childhood, cerebellar ataxia (CA). We will discuss and summarize the neuroimaging findings of either the most common or the most important causes of CA in childhood or present causes of pediatric CA with pathognomonic findings on MRI. The various pediatric CAs will be categorized and presented according to (a) the cause of ataxia (acquired/disruptive vs. inherited/genetic) and (b) the temporal evolution of symptoms (acute/subacute, chronic, progressive, nonprogressive, and recurrent). In addition, several illustrative cases with their key imaging findings will be presented.

Myelin oligodendrocyte glycoprotein antibodies in genetic leukodystrophies

Accumulation of intermediate metabolites due to enzyme deficiencies and demyelination can provoke inflammation in genetic leukodystrophies. Thirty patients with genetic leukodystrophy and 48 healthy control sera were tested for anti-myelin oligodendrocyte glycoprotein (MOG) antibodies by fixed and/or live cell-based assays. MOG-IgG was detected in two late infantile metachromatic leukodystrophy (MLD) cases, both of which were also weakly positive for IgG1, and one with IgG3 as the dominant anti-MOG IgG subclass. MOG-IgG was borderline positive in a vanishing white matter (VWM) disease patient. These results suggest that inherited metabolic or degenerative processes can have an autoimmune component, possibly as an epiphenomenon.

COVID-19 Vaccine-A Potential Trigger for MOGAD Transverse Myelitis in a Teenager-A Case Report and a Review of the Literature

MOGAD-transverse myelitis is a rare disorder in children and adults, but with a higher incidence in pediatric patients. We report a case of MOGAD-transverse myelitis in a boy who was admitted to hospital with bilateral motor deficit of the lower limbs associated with the impossibility of defecating and urinating. The symptoms progressively developed with severe fatigue within the week prior to admission, with the impossibility to stand occurring 36 h before admission. The anamnesis found that he was vaccinated for COVID-19 approximately 6 weeks before admission to our clinic. The laboratory tests revealed a normal complete cellular blood count, without any signs of inflammation or infection, except for both cryoglobulins and IgG anti-MOG antibodies. MRI showed a T2 hypersignal on vertebral segments C2-C5, Th2-Th5 and Th7-Th11, confirming the diagnosis of longitudinally extensive transverse myelitis. The patient received intravenous high-dose methylprednisolone (1 g) for 5 days, associated with prophylactic antibiotic treatment, subcutaneous low-molecular-weight heparin and other supportive treatment. The patient was discharged on the 12th day of admission, able to walk without support and with no bladder or bowel dysfunction. We can conclude that an early diagnosis was essential for improving the patient's long-term outcome.

Children suspected of having intracranial infection with normal brain magnetic resonance imaging may be associated with the myelin oligodendrocyte glycoprotein antibody

PURPOSE

To confirm whether encephalitis due to unknown causes but with normal brain magnetic resonance imaging (MRI) may be associated with the myelin oligodendrocyte glycoprotein (MOG) antibody.

METHODS

We retrospectively analyzed and summarized the characteristics of three patients initially suspected of having intracranial infections with normal brain MRI, and ultimately tested positive for anti-MOG antibody.

RESULTS

The three patients mainly presented with long-term fever accompanied by headaches and drowsiness. Auxiliary examinations showed obvious leukocytosis in peripheral blood and leukocytosis and increased protein expression in cerebrospinal fluid (CSF); furthermore, brain MRI was normal. These findings suggested intracranial infection, especially bacterial meningitis. No patient showed a response to prolonged anti-bacterial therapy; however, they recovered with glucocorticoid therapy, which was prescribed after anti-MOG antibodies were detected in the serum and CSF samples.

CONCLUSION

Anti-MOG antibody detection should be performed early for patients with suspected encephalitis due to unknown causes with normal brain MRI, to identify whether they have MOG antibody-associated diseases (MOGAD).