Evolution of brain MRI lesions in paediatric myelin-oligodendrocyte glycoprotein antibody-associated disease (MOGAD) and its relevance to disease course.

BACKGROUND: Lesion resolution is often observed in children with myelin-oligodendrocyte glycoprotein antibody-associated disease (MOGAD), and asymptomatic lesions are less commonly reported in MOGAD than in multiple sclerosis (MS). OBJECTIVE: We aimed to evaluate brain MRI changes over time in paediatric MOGAD. METHODS: Retrospective study in eight UK paediatric neuroscience centres. Acute brain MRI and available follow-up MRIs were reviewed. Predictors for lesion dynamic were evaluated using multivariable regression and Kaplan-Meier survival analyses were used to predict risk of relapse, disability and MOG-Ab status. RESULTS: 200 children were included (MOGAD 97; MS 103). At first MRI post attack, new symptomatic and asymptomatic lesions were seen more often in MS versus MOGAD (52/103 vs 28/97; p=0.002 and 37/103 vs 11/97; p<0.001); 83% of patients with MOGAD showed at least one lesion's resolution at first follow-up scan, and 23% had normal MRI. Only 1 patient with MS had single lesion resolution; none had normal MRI. Disappearing lesions in MOGAD were seen in 40% after the second attack, 21% after third attack and none after the fourth attack.New lesions at first follow-up scan were associated with increased likelihood of relapse (p=0.02) and persistent MOG-Ab serostatus (p=0.0016) compared with those with no new lesions. Plasma exchange was associated with increased likelihood of lesion resolution (p=0.01). Longer time from symptom onset to steroids was associated with increased likelihood of new lesions; 50% increase at 20 days (p=0.01). CONCLUSIONS: These striking differences in lesion dynamics between MOGAD and MS suggest greater potential to repair. Early treatment with steroids and plasma exchange is associated with reduced likelihood of new lesions.

Optic chiasm involvement in multiple sclerosis, aquaporin-4 antibody-positive neuromyelitis optica spectrum disorder and myelin oligodendrocyte glycoprotein-associated disease.

BACKGROUND: Optic neuritis (ON) is a common feature of inflammatory demyelinating diseases (IDDs) such as multiple sclerosis (MS), aquaporin 4-antibody neuromyelitis optica spectrum disorder (AQP4 + NMOSD) and myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD). However, the involvement of the optic chiasm (OC) in IDD has not been fully investigated. AIMS: To examine OC differences in non-acute IDD patients with (ON+) and without ON (ON-) using magnetisation transfer ratio (MTR), to compare differences between MS, AQP4 + NMOSD and MOGAD and understand their associations with other neuro-ophthalmological markers. METHODS: Twenty-eight relapsing-remitting multiple sclerosis (RRMS), 24 AQP4 + NMOSD, 28 MOGAD patients and 32 healthy controls (HCs) underwent clinical evaluation, MRI and optical coherence tomography (OCT) scan. Multivariable linear regression models were applied. RESULTS: ON + IDD patients showed lower OC MTR than HCs (28.87 ± 4.58 vs 31.65 ± 4.93; p = 0.004). When compared with HCs, lower OC MTR was found in ON + AQP4 + NMOSD (28.55 ± 4.18 vs 31.65 ± 4.93; p = 0.020) and MOGAD (28.73 ± 4.99 vs 31.65 ± 4.93; p = 0.007) and in ON- AQP4 + NMOSD (28.37 ± 7.27 vs 31.65 ± 4.93; p = 0.035). ON+ RRMS had lower MTR than ON- RRMS (28.87 ± 4.58 vs 30.99 ± 4.76; p = 0.038). Lower OC MTR was associated with higher number of ON (regression coefficient (RC) = -1.15, 95% confidence interval (CI) = -1.819 to -0.490, p = 0.001), worse visual acuity (RC = -0.026, 95% CI = -0.041 to -0.011, p = 0.001) and lower peripapillary retinal nerve fibre layer (pRNFL) thickness (RC = 1.129, 95% CI = 0.199 to 2.059, p = 0.018) when considering the whole IDD group. CONCLUSION: OC microstructural damage indicates prior ON in IDD and is linked to reduced vision and thinner pRNFL.

The emerging spectrum of fetal acetylcholine receptor antibody-related disorders (FARAD).

In utero exposure to maternal antibodies targeting the fetal acetylcholine receptor isoform (fAChR) can impair fetal movement, leading to arthrogryposis multiplex congenita (AMC). Fetal AChR antibodies have also been implicated in apparently rare, milder myopathic presentations termed fetal acetylcholine receptor inactivation syndrome (FARIS). The full spectrum associated with fAChR antibodies is still poorly understood. Moreover, since some mothers have no myasthenic symptoms, the condition is likely underreported, resulting in failure to implement effective preventive strategies. Here we report clinical and immunological data from a multicentre cohort (n = 46 cases) associated with maternal fAChR antibodies, including 29 novel and 17 previously reported with novel follow-up data. Remarkably, in 50% of mothers there was no previously established myasthenia gravis (MG) diagnosis. All mothers (n = 30) had AChR antibodies and, when tested, binding to fAChR was often much greater than that to the adult AChR isoform. Offspring death occurred in 11/46 (23.9%) cases, mainly antenatally due to termination of pregnancy prompted by severe AMC (7/46, 15.2%), or during early infancy, mainly from respiratory failure (4/46, 8.7%). Weakness, contractures, bulbar and respiratory involvement were prominent early in life, but improved gradually over time. Facial (25/34; 73.5%) and variable peripheral weakness (14/32; 43.8%), velopharyngeal insufficiency (18/24; 75%) and feeding difficulties (16/36; 44.4%) were the most common sequelae in long-term survivors. Other unexpected features included hearing loss (12/32; 37.5%), diaphragmatic paresis (5/35; 14.3%), CNS involvement (7/40; 17.5%) and pyloric stenosis (3/37; 8.1%). Oral salbutamol used empirically in 16/37 (43.2%) offspring resulted in symptom improvement in 13/16 (81.3%). Combining our series with all previously published cases, we identified 21/85 mothers treated with variable combinations of immunotherapies (corticosteroids/intravenous immunoglobulin/plasmapheresis) during pregnancy either for maternal MG symptom control (12/21 cases) or for fetal protection (9/21 cases). Compared to untreated pregnancies (64/85), maternal treatment resulted in a significant reduction in offspring deaths (P < 0.05) and other complications, with treatment approaches involving intravenous immunoglobulin/ plasmapheresis administered early in pregnancy most effective. We conclude that presentations due to in utero exposure to maternal (fetal) AChR antibodies are more common than currently recognized and may mimic a wide range of neuromuscular disorders. Considering the wide clinical spectrum and likely diversity of underlying mechanisms, we propose 'fetal acetylcholine receptor antibody-related disorders' (FARAD) as the most accurate term for these presentations. FARAD is vitally important to recognize, to institute appropriate management strategies for affected offspring and to improve outcomes in future pregnancies. Oral salbutamol is a symptomatic treatment option in survivors.

Leigh syndrome mimicking neuromyelitis optica spectrum disorder (NMOSD).

We report two children with molecularly confirmed mitochondrial disease mimicking Neuromyelitis Optica Spectrum Disorder (NMOSD). The first patient presented at the age of 15 months with acute deterioration following a pyrexial illness with clinical features localising to the brainstem and spinal cord. The second patient presented at 5 years with acute bilateral visual loss. In both cases, MOG and AQP4 antibodies were negative. Both patients died within a year of symptoms onset from respiratory failure. Arriving at an early genetic diagnosis is important for redirection of care and avoiding potentially harmful immunosuppressant therapies.

Comparison of MRI T2-lesion evolution in pediatric MOGAD, NMOSD, and MS.

BACKGROUND: Magnetic resonance imaging (MRI) T2-lesions resolve more often in myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD) than aquaporin-4 IgG-positive neuromyelitis optica spectrum disorder (AQP4 + NMOSD) and multiple sclerosis (MS) in adults but few studies analyzed children. OBJECTIVE: The main objective of this study is to investigate MRI T2-lesion evolution in pediatric MOGAD, AQP4 + NMOSD, and MS. METHODS: Inclusion criteria were as follows: (1) first clinical attack; (2) abnormal MRI (⩽6 weeks); (3) follow-up MRI beyond 6 months without relapses in that region; and (4) age < 18 years. An index T2-lesion (symptomatic/largest) was identified, and T2-lesion resolution or persistence on follow-up MRI was determined. RESULTS: We included 56 patients (MOGAD, 21; AQP4 + NMOSD, 8; MS, 27) with 69 attacks. Index T2-lesion resolution was more frequent in MOGAD (brain 9 of 15 [60%]; spine 8 of 12 [67%]) than AQP4 + NMOSD (brain 1 of 4 [25%]; spine 0 of 7 [0%]) and MS (brain 0 of 18 [0%]; spine 1 of 13 [8%]), p < 0.01. Resolution of all T2-lesions occurred more often in MOGAD (brain 6 of 15 [40%]; spine 7 of 12 [58%]) than AQP4 + NMOSD (brain 1 of 4 [25%]; spine 0 of 7 [0%]), and MS (brain 0 of 18 [0%]; spine 1 of 13 [8%]), p < 0.01. Reductions in median index T2-lesion area were greater in MOGAD (brain, 305 mm; spine, 23 mm) than MS (brain, 42 mm [p<0.001]; spine, 10 mm [p<0.001]) without differing from AQP4 + NMOSD (brain, 133 mm [p=0.42]; spine, 19.5 mm [p=0.69]). CONCLUSION: In children, MRI T2-lesions resolved more often in MOGAD than AQP4 + NMOSD and MS which is similar to adults suggesting these differences are related to pathogenesis rather than age.

ECTRIMS/EAN consensus on vaccination in people with multiple sclerosis: Improving immunization strategies in the era of highly active immunotherapeutic drugs.

BACKGROUND: With the new highly active drugs available for people with multiple sclerosis (pwMS), vaccination becomes an essential part of the risk management strategy. OBJECTIVE: To develop a European evidence-based consensus for the vaccination strategy of pwMS who are candidates for disease-modifying therapies (DMTs). METHODS: This work was conducted by a multidisciplinary working group using formal consensus methodology. Clinical questions (defined as population, interventions, and outcomes) considered all authorized DMTs and vaccines. A systematic literature search was conducted and quality of evidence was defined according to the Oxford Centre for Evidence-Based Medicine Levels of Evidence. The recommendations were formulated based on the quality of evidence and the risk-benefit balance. RESULTS: Seven questions, encompassing vaccine safety, vaccine effectiveness, global vaccination strategy and vaccination in sub-populations (pediatric, pregnant women, elderly and international travelers) were considered. A narrative description of the evidence considering published studies, guidelines, and position statements is presented. A total of 53 recommendations were agreed by the working group after three rounds of consensus. CONCLUSION: This first European consensus on vaccination in pwMS proposes the best vaccination strategy according to current evidence and expert knowledge, with the goal of homogenizing the immunization practices in pwMS.

Intravenous immunoglobulin treatment for acute attacks in myelin oligodendrocyte glycoprotein antibody disease.

BACKGROUND: The potential therapeutic benefit of intravenous immunoglobulins (IVIGs) for acute attacks of myelin oligodendrocyte glycoprotein antibody disease (MOGAD) is unknown. OBJECTIVE: The objective was to describe the outcomes of IVIG treatment for acute MOGAD attacks. METHODS: A retrospective observational study involving seven tertiary neuroimmunology centers. Data collection included patients' demographics, Expanded Disability Status Scale (EDSS), and visual acuity (VA) before the attack, at the nadir of the attack before IVIG treatment, and at follow-up visits ⩾3 months after treatment. RESULTS: Thirty-nine patients were included, of which 21 (53.8%) were female. The median age was 23 years (range 5-74 years), and the median disease duration was 4 months (range 0-93 months). The most common type of attack treated with IVIG was isolated optic neuritis (ON) (unilateral n = 14, bilateral n = 5, associated with transverse myelitis (TM), n = 1), followed by acute disseminated encephalomyelitis (ADEM) (n = 8), multifocal (n = 7), TM (n = 3), brainstem (n = 1), and other encephalitis (n = 1). A significant improvement in both the EDSS and VA measures was observed at follow-up compared to the time of IVIG treatment initiation (p < 0.0001 for both outcome measures). CONCLUSION: IVIG may be an effective treatment option for acute MOGAD attacks. Further prospective studies are warranted to validate our results.

European Committee for Treatment and Research in Multiple Sclerosis and European Academy of Neurology consensus on vaccination in people with multiple sclerosis: Improving immunization strategies in the era of highly active immunotherapeutic drugs.

BACKGROUND AND PURPOSE: With the new highly active drugs available for people with multiple sclerosis (pwMS), vaccination becomes an essential part of the risk management strategy. We aimed to develop a European evidence-based consensus for the vaccination strategy of pwMS who are candidates for disease-modifying therapies (DMTs). METHODS: This work was conducted by a multidisciplinary working group using formal consensus methodology. Clinical questions (defined as population, interventions and outcomes) considered all authorized DMTs and vaccines. A systematic literature search was conducted and quality of evidence was defined according to the Oxford Centre for Evidence-Based Medicine Levels of Evidence. The recommendations were formulated based on the quality of evidence and the risk-benefit balance. RESULTS: Seven questions, encompassing vaccine safety, vaccine effectiveness, global vaccination strategy and vaccination in subpopulations (pediatric, pregnant women, elderly and international travelers) were considered. A narrative description of the evidence considering published studies, guidelines and position statements is presented. A total of 53 recommendations were agreed by the working group after three rounds of consensus. CONCLUSION: This first European consensus on vaccination in pwMS proposes the best vaccination strategy according to current evidence and expert knowledge, with the goal of homogenizing the immunization practices in pwMS.

Early predictors of disability of paediatric-onset AQP4-IgG-seropositive neuromyelitis optica spectrum disorders.

OBJECTIVE: To describe onset clinical features predicting time to first relapse and time to long-term visual, motor and cognitive disabilities in paediatric-onset aquaporin-4 antibody (AQP4-IgG) neuromyelitis optica spectrum disorders (NMOSDs). METHODS: In this retrospective UK multicentre cohort study, we recorded clinical data of paediatric-onset AQP4-IgG NMOSD. Univariate and exploratory multivariable Cox proportional hazard models were used to identify long-term predictors of permanent visual disability, Expanded Disability Status Scale (EDSS) score of 4 and cognitive impairment. RESULTS: We included 49 paediatric-onset AQP4-IgG patients (38.8% white, 34.7% black, 20.4% Asians and 6.1% mixed), mean onset age of 12±4.1 years, and 87.7% were female. Multifocal onset presentation occurred in 26.5% of patients, and optic nerve (47%), area postrema/brainstem (48.9%) and encephalon (28.6%) were the most involved areas. Overall, 52.3% of children had their first relapse within 1 year from disease onset. Children with onset age <12 years were more likely to have an earlier first relapse (p=0.030), despite showing no difference in time to immunosuppression compared with those aged 12-18 years at onset. At the cohort median disease duration of 79 months, 34.3% had developed permanent visual disability, 20.7% EDSS score 4 and 25.8% cognitive impairment. Visual disability was associated with white race (p=0.032) and optic neuritis presentations (p=0.002). Cognitive impairment was predicted by cerebral syndrome presentations (p=0.048), particularly if resistant to steroids (p=0.034). CONCLUSIONS: Age at onset, race, onset symptoms and resistance to acute therapy at onset attack predict first relapse and long-term disabilities. The recognition of these predictors may help to power future paediatric clinical trials and to direct early therapeutic decisions in AQP4-IgG NMOSD.

Radiologically isolated aquaporin-4 antibody neuromyelitis optica spectrum disorder.

Aquaporin-4 antibody (AQP4-Ab) Neuromyelitis Optica Spectrum Disorder (NMOSD) is a rare neuroinflammatory syndrome presenting predominantly with optic neuritis and transverse myelitis. We report a case of radiologically isolated longitudinally extensive optic neuritis in an asymptomatic 12-year-old female with positive serum AQP4-Ab, with resolution of imaging changes after immune therapy. By contrast to patients with radiologically isolated syndrome, of which some will never convert to multiple sclerosis, the pathogenicity of AQP4-Ab in the context of sub-clinical disease, supported treatment in our patient. Given the severe morbidity in AQP4-Ab NMOSD, prognostic biomarkers for disease severity are required to guide optimal therapy for patients.

Isolated central nervous system familial hemophagocytic lymphohistiocytosis (fHLH) presenting as a mimic of demyelination in children.

Isolated central nervous system (CNS) presentations of haemophagocytic lymphohistiocytosis (HLH), traditionally a systemic inflammatory condition, have been reported in adults and children. We identified nine patients with a diagnosis of isolated CNS familial hemophagocytic lymphohistiocytosis (fHLH) with symptom onset <18 years of age, and one asymptomatic sibling. Children with atypical chronic/recurrent CNS inflammation should be considered for immunological and genetic panel testing for fHLH even in the absence of any systemic inflammatory features. Despite haematopoietic stem cell transplantation (HSCT) being a mainstay of treatment, treatment failure and high morbidity and mortality post-HSCT suggest that alternative immune therapies may be worth considering.

The risk of infections for multiple sclerosis and neuromyelitis optica spectrum disorder disease-modifying treatments: Eighth European Committee for Treatment and Research in Multiple Sclerosis Focused Workshop Review. April 2021.

Over the recent years, the treatment of multiple sclerosis (MS) and neuromyelitis optica spectrum disorder (NMOSD) has evolved very rapidly and a large number of disease-modifying treatments (DMTs) are now available. However, most DMTs are associated with adverse events, the most frequent of which being infections. Consideration of all DMT-associated risks facilitates development of risk mitigation strategies. An international focused workshop with expert-led discussions was sponsored by the European Committee for Treatment and Research in Multiple Sclerosis (ECTRIMS) and was held in April 2021 to review our current knowledge about the risk of infections associated with the use of DMTs for people with MS and NMOSD and corresponding risk mitigation strategies. The workshop addressed DMT-associated infections in specific populations, such as children and pregnant women with MS, or people with MS who have other comorbidities or live in regions with an exceptionally high infection burden. Finally, we reviewed the topic of DMT-associated infectious risks in the context of the current SARS-CoV-2 pandemic. Herein, we summarize available evidence and identify gaps in knowledge which justify further research.

Incidence of paediatric multiple sclerosis and other acquired demyelinating syndromes: 10-year follow-up surveillance study.

AIM: To describe a 10-year follow-up of children (<16y) with acquired demyelinating syndromes (ADS) from a UK-wide prospective surveillance study. METHOD: Diagnoses were retrieved from the patients' records via the patients' paediatric or adult neurologist using a questionnaire. Demyelinating phenotypes at follow-up were classified by an expert review panel. RESULTS: Twenty-four out of 125 (19.2%) children (64 males, 61 females; median age 10y, range 1y 4mo-15y 11mo), identified in the original study, were diagnosed with multiple sclerosis (incidence of 2.04/million children/year); 23 of 24 fulfilled 2017 McDonald criteria at onset. Aquaporin-4-antibody neuromyelitis optica spectrum disorders were diagnosed in three (2.4%, 0.26/million children/year), and relapsing myelin oligodendrocyte glycoprotein antibody-associated disease in five (4%, 0.43/million children/year). Three out of 125 seronegative patients relapsed and 85 of 125 (68%) remained monophasic over 10 years. Five of 125 patients (4%) originally diagnosed with ADS were reclassified during follow-up: three children diagnosed initially with acute disseminated encephalomyelitis were subsequently diagnosed with acute necrotising encephalopathy (RAN-binding protein 2 mutation), primary haemophagocytic lymphohistiocytosis (Munc 13-4 gene inversion), and anti-N-methyl-d-aspartate receptor encephalitis. One child initially diagnosed with optic neuritis was later diagnosed with vitamin B12 deficiency, and one presenting with transverse myelitis was subsequently diagnosed with Sjögren syndrome. INTERPRETATION: The majority of ADS presentations in children are monophasic, even at 10-year follow-up. Given the implications for treatment strategies, multiple sclerosis and central nervous system autoantibody mimics warrant extensive investigation.

What does first-line therapy mean for paediatric multiple sclerosis in the current era?

Paediatric multiple sclerosis (MS) is associated with higher relapse rate, rapid magnetic resonance imaging lesion accrual early in the disease course and worse cognitive outcome and physical disability in the long term compared to adult-onset disease. Current treatment strategies are largely centre-specific and reliant on adult protocols. The aim of this review is to examine which treatment options should be considered first line for paediatric MS and we attempt to answer the question if injectable first-line disease-modifying therapies (DMTs) are still an optimal option. To answer this question, we review the effects of early onset disease on clinical course and outcomes, with specific considerations on risks and benefits of treatments for paediatric MS. Considering the impact of disease activity on brain atrophy, cognitive impairment and development of secondary progressive MS at a younger age, we would recommend treating paediatric MS as a highly active disease, favouring the early use of highly effective DMTs rather than injectable DMTs.

Primary progressive multiple sclerosis presenting under the age of 18 years: Fact or fiction?

Previous cohort studies on paediatric multiple sclerosis (MS) have reported very low frequencies for a primary progressive MS (PPMS) course ranging from 0% to 7%. We identified six patients presenting prior to the age of 18 years and fulfilling the 2017 McDonald Criteria for PPMS. Presentation with progressive neurological symptoms and signs in young people should prompt evaluation for genetic causes such as leukodystrophies, hereditary spastic paraparesis and mitochondrial diseases given the rarity of primary progressive course in paediatric MS. In the absence of an alternative diagnosis, with new therapeutic options becoming available for PPMS, this diagnosis should then be considered.

Improved performance of the 2017 McDonald criteria for diagnosis of multiple sclerosis in children in a real-life cohort.

OBJECTIVE: To compare the performance of the 2017 McDonald criteria with that of the 2010 criteria for the diagnosis of multiple sclerosis (MS) in children in the clinical setting. METHODS: In this retrospective, multi-centre study, we identified children who presented with symptoms suggestive of a clinically isolated syndrome (CIS) and were followed up for at least 2 years or until their second attack. RESULTS: Of 156 children with CIS followed up for a median of 4.17 years, 94 (60.3%) were diagnosed with MS. In all, 83 (88.3%) of these fulfilled the 2010 dissemination in space (DIS) criteria at onset. Three additional children fulfilled the 2017 DIS criteria because of the inclusion of symptomatic lesions. Of the 59 children with MS who underwent post-gadolinium magnetic resonance imaging (MRI), 44 (74.6%) fulfilled the 2010 dissemination in time (DIT) criteria at baseline. When the presence of oligoclonal bands (OCBs) was used to substitute DIT, an additional 35 children (79/94, 84.0%) were diagnosed with MS according to the 2017 criteria. The 2017 criteria had higher accuracy (87.2% vs 66.7%), higher sensitivity (84.0% vs 46.8%), but reduced specificity (91.9% vs 96.8%) when compared to the 2010 criteria. CONCLUSION: The improved performance of the 2017 criteria when compared to the 2010 criteria was predominantly due to the inclusion of intrathecal OCBs.

Early predictors of epilepsy and subsequent relapse in children with acute disseminated encephalomyelitis.

OBJECTIVE: To identify predictors of epilepsy and clinical relapses in children presenting with acute disseminated encephalomyelitis (ADEM). METHODS: Children presenting with ADEM between 2005 and 2017 and tested clinically for MOG-Ab were identified from three tertiary paediatric neurology centres in the United Kingdom. Patients were followed up for a median of 6 years (range, 1-16 years). RESULTS: A total of 74 children were studied (38 females; median age at first presentation: 4.5 years (range, 1.4-16 years)). MOG-Ab was positive in 50/74 (67.6%) of cases, and 27 (54%) of MOG-Ab positive children presented with a neurological relapse over time. MOG-Ab was more frequently positive in the relapsing group than in the monophasic group (27/31 vs 23/43; odds ratio 5.9 (95% CI: 1.8-19.7); p = 0.002). 16/74 (22%) children had seizures during the acute presentation with ADEM and 12/74 (16.2%) patients were diagnosed with post-ADEM epilepsy. The diagnosis of post-ADEM epilepsy was more frequently observed in children with relapsing disease than monophasic disease (10/31 vs 2/43; odds ratio 9.8 (95% confidence interval (CI): 2.0-48.7); p = 0.003), in children who had positive intrathecal oligoclonal bands than those with negative bands (4/7 vs 4/30; odds ratio 8.7 (95% CI: 1.4-54.0); p = 0.027) and in children who had positive MOG-Ab than negative MOG-Ab cases (11/12 vs 39/62; odds ratio 6.5 (95% CI:0.8-53.6); p = 0.051). CONCLUSION: A higher relapse rate and a greater risk of post-ADEM epilepsy in children with MOG-Ab-associated disease may indicate a chronic disease with immune-mediated seizures in these children.

Diagnostic algorithm for children presenting with epilepsia partialis continua.

OBJECTIVE: To characterize a cohort of children with epilepsia partialis continua (EPC) and develop a diagnostic algorithm incorporating key differential diagnoses. METHODS: Children presenting with EPC to a tertiary pediatric neurology center between 2002 and 2019 were characterized. RESULTS: Fifty-four children fulfilled EPC criteria. Median age at onset was 7 years (range 0.6-15), with median follow-up of 4.3 years (range 0.2-16). The diagnosis was Rasmussen encephalitis (RE) in 30 of 54 (56%), a mitochondrial disorder in 12 of 54 (22.2%), and magnetic resonance imaging (MRI) lesion-positive focal epilepsy in 6 of 54 (11.1%). No diagnosis was made in 5 of 54 (9%). Children with mitochondrial disorders developed EPC earlier; each additional year at presentation reduced the odds of a mitochondrial diagnosis by 26% (P = .02). Preceding developmental concerns (odds ratio [OR] 22, P < .001), no seizures prior to EPC (OR 22, P < .001), bilateral slowing on electroencephalogram (EEG) (OR 26, P < .001), and increased cerebrospinal fluid (CSF) protein level (OR 16) predicted a mitochondrial disorder. Asymmetry or hemiatrophy was evident on MRI at presentation with EPC in 18 of 30 (60%) children with RE, and in the remainder at a median of 6 months (range 3-15) after EPC onset. The first diagnostic test is brain MRI. Hemiatrophy may permit a diagnosis of RE with unilateral clinical and EEG findings. For children in whom a diagnosis of RE cannot be made on first scan but the clinical and radiological presentation resembles RE, repeat imaging every 6 months is recommended to detect progressive unicortical hemiatrophy, and brain biopsy should be considered. Evidence of intrathecal inflammation (oligoclonal bands and raised neopterin) can be supportive. In children with bihemispheric EPC, rapid polymerase gamma testing is recommended and if negative, sequencing mtDNA and whole-exome sequencing on blood-derived DNA should be performed. SIGNIFICANCE: Children presenting with EPC due to a mitochondrial disorder show clinical features distinguishing them from RE and structural epilepsies. A diagnostic algorithm for children with EPC will allow targeted investigation and timely diagnosis.

Paediatric MOG antibody-associated ADEM with complex movement disorder: A case report.

Myelin oligodendrocyte glycoprotein antibodies (MOG-Abs) are a well-recognized cause of acquired demyelinating syndromes in both adult and children. Despite basal ganglia involvement on imaging, movement disorder is not a cardinal feature. We describe a 2-year-9-month-old girl who presented with severe encephalopathy with aphasia, seizures and a complex movement disorder with dystonic posturing and tonic eye deviation. Neuroimaging revealed subtle asymmetrical predominantly white matter signal changes. MOG-Abs were positive in the serum. Other known pathogenic autoantibodies including N-methyl-D-aspartate receptor antibodies (NMDAR-Abs) were negative. The patient made a complete recovery following 2-week corticosteroid treatment. This case highlights the need for MOG-Ab testing in children with suspected autoimmune encephalopathies.

Paediatric multiple sclerosis: a new era in diagnosis and treatment.

Multiple sclerosis is a chronic immune-mediated demyelinating disease of the central nervous system. The diagnosis of multiple sclerosis in children, as in adults, requires evidence of dissemination of inflammatory activity in more than one location in the central nervous system (dissemination in space) and recurrent disease over time (dissemination in time). The identification of myelin oligodendrocyte glycoprotein antibodies (MOG-Ab) and aquaporin-A antibodies (AQP4-Ab), and the subsequent discovery of their pathogenic mechanisms, have led to a shift in the classification of relapsing demyelinating syndromes. This is reflected in the 2017 revised criteria for the diagnosis of multiple sclerosis, which emphasizes the exclusion of multiple sclerosis mimics and aims to enable earlier diagnosis and thus treatment initiation. The long-term efficacy of individual therapies initiated in children with multiple sclerosis is hard to evaluate, owing to the small numbers of patients who have the disease, the relatively high number of patients who switch therapy, and the need for long follow-up studies. Nevertheless, an improvement in prognosis with a globally reduced annual relapse rate in children with multiple sclerosis is now observed compared with the pretreatment era, indicating a possible long-term effect of therapies. Given the higher relapse rate in children compared with adults, and the impact multiple sclerosis has on cognition in the developing brain, there is a question whether rapid escalation or potent agents should be used in children, while the short- and long-term safety profiles of these drugs are being established. With the results of the first randomized controlled trial of fingolimod versus interferon-ß1a in paediatric multiple sclerosis published in 2018 and several clinical trials underway, there is hope for further progress in the field of paediatric multiple sclerosis. WHAT THIS PAPER ADDS: Early and accurate diagnosis of multiple sclerosis is crucial. The discovery of antibody-mediated demyelination has changed the diagnosis and management of relapsing demyelination syndromes. Traditional escalation therapy is being challenged by induction therapy.

ESCLEROSIS MÚLTIPLE PEDIÁTRICA: UNA NUEVA ERA EN EL DIAGNÓSTICO Y TRATAMIENTO: La esclerosis múltiple es una enfermedad desmielinizante crónica mediada por el sistema inmunitario del sistema nervioso central. El diagnóstico de esclerosis múltiple en niños, como en adultos, requiere evidencia de diseminación de actividad inflamatoria en más de un lugar en el sistema nervioso central (diseminación en el espacio) y enfermedad recurrente a lo largo del tiempo (diseminación en el tiempo). La identificación de los anticuerpos de la glicoproteína oligodendrocítica de la mielina (MOG-Ab) y los anticuerpos de la acuaporina-A (AQP4-Ab), y el posterior descubrimiento de sus mecanismos patógenos, han conducido a un cambio en la clasificación de los síndromes desmielinizantes recurrentes. Esto se refleja en los criterios revisados ​​de 2017 para el diagnóstico de esclerosis múltiple, que enfatiza la exclusión de los imitadores de la esclerosis múltiple y tiene como objetivo permitir un diagnóstico más temprano y, por lo tanto, el inicio del tratamiento. La eficacia a largo plazo de las terapias individuales iniciadas en niños con esclerosis múltiple es difícil de evaluar, debido a la pequeña cantidad de pacientes que tienen la enfermedad, la cantidad relativamente alta de pacientes que cambian de terapia y la necesidad de estudios de seguimiento prolongados. Sin embargo, ahora se observa una mejora en el pronóstico con una tasa de recaída anual globalmente reducida en niños con esclerosis múltiple en comparación con la era anterior al tratamiento previo, lo que indica un posible efecto a largo plazo de las terapias. Debido a la mayor tasa de recaída en niños en comparación con los adultos, y el impacto que tiene la esclerosis múltiple en la cognición en el cerebro en desarrollo, existe la duda de si se deben usar agentes de aumento rápido o potentes en niños, mientras que los perfiles de seguridad a corto y largo plazo de estos medicamentos se están estableciendo. Con los resultados del primer ensayo controlado aleatorio de fingolimod versus interferón-ß1a en esclerosis múltiple pediátrica publicado en 2018 y varios ensayos clínicos en curso, existe la esperanza de un mayor progreso en el campo de la esclerosis múltiple pediátrica.

ESCLEROSE MÚLTIPLA PEDIÁTRICA: UMA NOVA ERA NO DIAGNÓSTICO E TRATAMENTO: A esclerose múltipla é uma doença desmielinizante imunomediada crônica do sistema nervoso central. O diagnóstico de esclerose múltipla em crianças, como em adultos, exige evidência de disseminação da atividade inflamatória em mais de um local no sistema nervoso central (disseminação no espaço) e doença recorrente ao longo do tempo (disseminação no tempo). A identificação de anticorpos anti-glicoproteína de mielina do oligodendrócito (MOG-Ab) e anticorpos anti-aquaporina A (AQP4-Ab), e a subsequente descoberta de seus mecanismos patogênicos, levaram a uma mudança na classificação das síndromes desmielinizantes recidivantes. Isso se reflete nos critérios revisados de 2017 para o diagnóstico de esclerose múltipla, que enfatizam a exclusão de transtornos que mimetizam esclerose múltipla e visam permitir o diagnóstico precoce e, portanto, o início do tratamento. É difícil avaliar a eficácia a longo prazo de terapias individuais iniciadas em crianças com esclerose múltipla, devido ao pequeno número de pacientes que têm a doença, o número relativamente alto de pacientes que trocam de terapia e a necessidade de estudos de acompanhamento a longo prazo. No entanto, uma melhora no prognóstico com uma taxa de recaída anual globalmente reduzida em crianças com esclerose múltipla é agora observada em comparação com a era pré-tratamento, indicando um possível efeito a longo prazo das terapias. Dada a maior taxa de recaída em crianças em comparação com adultos, e o impacto da esclerose múltipla na cognição no cérebro em desenvolvimento, há uma questão se a escalada rápida ou agentes potentes devem ser usados em crianças, enquanto os perfis de segurança de curto e longo prazo destas drogas estão sendo estabelecidos. Com os resultados do primeiro estudo controlado randomizado de fingolimode versus interferon-ß1a na esclerose múltipla pediátrica publicado em 2018 e vários ensaios clínicos em andamento, há esperança de mais progressos no campo da esclerose múltipla pediátrica.