Rituximab in patients with pediatric multiple sclerosis and other demyelinating disorders of the CNS: Practical considerations.

Anti-CD20 therapies have established efficacy in the treatment of immune-mediated neurological and non-neurological diseases. Rituximab, one of the first B-cell-directed therapies, is relatively inexpensive compared to newer anti-CD20 molecules, is available in many countries, and has been used off-label in pediatric patients with neuroimmune conditions. The objective of this paper is to describe the experience with rituximab in pediatric multiple sclerosis and other inflammatory immune-mediated disorders of the central nervous system (CNS), and to define a protocol for its use in clinical practice, in particular addressing doses, interval of administration, duration of treatment, and tests to perform at baseline and during follow-up.

Self-antigen tetramers discriminate between myelin autoantibodies to native or denatured protein.

The role of autoantibodies in the pathogenesis of multiple sclerosis (MS) and other demyelinating diseases is controversial, in part because widely used western blotting and ELISA methods either do not permit the detection of conformation-sensitive antibodies or do not distinguish them from conformation-independent antibodies. We developed a sensitive assay based on self-assembling radiolabeled tetramers that allows discrimination of antibodies against folded or denatured myelin oligodendrocyte glycoprotein (MOG) by selective unfolding of the antigen domain. The tetramer radioimmunoassay (RIA) was more sensitive for MOG autoantibody detection than other methodologies, including monomer-based RIA, ELISA or fluorescent-activated cell sorting (FACS). Autoantibodies from individuals with acute disseminated encephalomyelitis (ADEM) selectively bound the folded MOG tetramer, whereas sera from mice with experimental autoimmune encephalomyelitis induced with MOG peptide immunoprecipitated only the unfolded tetramer. MOG-specific autoantibodies were identified in a subset of ADEM but only rarely in adult-onset MS cases, indicating that MOG is a more prominent target antigen in ADEM than MS.

A Clinical Neurological Approach to the Child With Adenosine Deaminase Deficiency.

BACKGROUND: Severe combined immunodeficiency secondary to adenosine deaminase deficiency is rare. The deficiency of this enzyme results in the accumulation of substrates in the tissues, including the brain. Clinical signs of neurological involvement may include seizures, neurodevelopmental disorders, hypotonia, and sensorineural hearing loss. Hematopoietic stem cell transplantation corrects the failure of the immune system but not the neurological involvement. OBJECTIVES: To describe the spectrum of neurological complications identified in a series of children with severe combined immunodeficiency due to adenosine deaminase deficiency. Additionally, we propose a neurological approach including electrophysiological, radiological, and neurocognitive studies to address this group of children in an efficient and timely manner. METHODS: A descriptive, observational, retro-, and prospective analysis of patients with a confirmed immunological diagnosis seen between 1996 and 2021 and referred to the Department of Neurology for neurological evaluation was conducted. RESULTS: Ten patients met the inclusion criteria. The median age at diagnosis was 4 months (range, 1-36 months). All patients had neurodevelopmental delay with hypotonia in six, language delay in three, sensorineural hearing loss in four, and spastic paraparesis in one patient. Two children developed an epileptic syndrome, consisting of generalized epilepsy in one and focal epilepsy in the other. Neuroimaging showed brain calcifications in the basal ganglia and/or centrum semiovale in four patients and enlarged subarachnoid spaces in two other patients. CONCLUSION: In this pediatric series, the rate of neurological involvement associated with abnormalities on neuroimaging was high. Although this involvement could be related to accumulation of adenosine metabolites in the central nervous system, the possibility of associated chronic infections should be ruled out. Given the neurological manifestations, it is important to involve the pediatric neurologist in the multidisciplinary follow-up team.

The diagnostic workup of children with the radiologically isolated syndrome differs by age and by sex.

BACKGROUND: Cerebrospinal fluid (CSF) and spinal MRIs are often obtained in children with the radiologically isolated syndrome (RIS) for diagnosis and prognosis. Factors affecting the frequency and timing of these tests are unknown. OBJECTIVE: To determine whether age or sex were associated with (1) having CSF or spinal MRI obtained or (2) the timing of these tests. METHODS: We analyzed children (≤ 18 y) with RIS enrolled in an international longitudinal study. Index scans met 2010/2017 multiple sclerosis (MS) MRI criteria for dissemination in space (DIS). We used Fisher's exact test and multivariable logistic regression (covariates = age, sex, MRI date, MRI indication, 2005 MRI DIS criteria met, and race). RESULTS: We included 103 children with RIS (67% girls, median age = 14.9 y). Children ≥ 12 y were more likely than children < 12 y to have CSF obtained (58% vs. 21%, adjusted odds ratio [AOR] = 4.9, p = 0.03). Pre-2017, girls were more likely than boys to have CSF obtained (n = 70, 79% vs. 52%, AOR = 4.6, p = 0.01), but not more recently (n = 30, 75% vs. 80%, AOR = 0.2, p = 0.1; p = 0.004 for interaction). Spinal MRIs were obtained sooner in children ≥ 12 y (median 11d vs. 159d, p = 0.03). CONCLUSIONS: Younger children with RIS may be at continued risk for misdiagnosis and misclassification of MS risk. Consensus guidelines are needed.

International Pediatric Multiple Sclerosis Study Group criteria for pediatric multiple sclerosis and immune-mediated central nervous system demyelinating disorders: revisions to the 2007 definitions.

BACKGROUND: There has been tremendous growth in research in pediatric multiple sclerosis (MS) and immune mediated central nervous system demyelinating disorders since operational definitions for these conditions were first proposed in 2007. Further, the International Pediatric Multiple Sclerosis Study Group (IPMSSG), which proposed the criteria, has expanded substantially in membership and in its international scope. OBJECTIVE: The purpose of this review is to revise the 2007 definitions in order to incorporate advances in delineating the clinical and neuroradiologic features of these disorders. METHODS: Through a consensus process, in which input was sought from the 150 members of the Study Group, criteria were drafted, revised and finalized. Final approval was sought through a web survey. RESULTS: Revised criteria are proposed for pediatric acute disseminated encephalomyelitis, pediatric clinically isolated syndrome, pediatric neuromyelitis optica and pediatric MS. These criteria were approved by 93% or more of the 56 Study Group members who responded to the final survey. CONCLUSIONS: These definitions are proposed for clinical and research purposes. Their utility will depend on the outcomes of their application in prospective research.

Serum autoantibodies to myelin peptides distinguish acute disseminated encephalomyelitis from relapsing-remitting multiple sclerosis.

BACKGROUND AND OBJECTIVE: Acute disseminated encephalomyelitis (ADEM) and relapsing-remitting multiple sclerosis (RRMS) share overlapping clinical, radiologic and laboratory features at onset. Because autoantibodies may contribute to the pathogenesis of both diseases, we sought to identify autoantibody biomarkers that are capable of distinguishing them. METHODS: We used custom antigen arrays to profile anti-myelin-peptide autoantibodies in sera derived from individuals with pediatric ADEM (n = 15), pediatric multiple sclerosis (Ped MS; n = 11) and adult MS (n = 15). Using isotype-specific secondary antibodies, we profiled both IgG and IgM reactivities. We used Statistical Analysis of Microarrays software to confirm the differences in autoantibody reactivity profiles between ADEM and MS samples. We used Prediction Analysis of Microarrays software to generate and validate prediction algorithms, based on the autoantibody reactivity profiles. RESULTS: ADEM was characterized by IgG autoantibodies targeting epitopes derived from myelin basic protein, proteolipid protein, myelin-associated oligodendrocyte basic glycoprotein, and alpha-B-crystallin. In contrast, MS was characterized by IgM autoantibodies targeting myelin basic protein, proteolipid protein, myelin-associated oligodendrocyte basic glycoprotein and oligodendrocyte-specific protein. We generated and validated prediction algorithms that distinguish ADEM serum (sensitivity 62-86%; specificity 56-79%) from MS serum (sensitivity 40-87%; specificity 62-86%) on the basis of combined IgG and IgM anti-myelin autoantibody reactivity to a small number of myelin peptides. CONCLUSIONS: Combined profiles of serum IgG and IgM autoantibodies identified myelin antigens that may be useful for distinguishing MS from ADEM. Further studies are required to establish clinical utility. Further biological assays are required to delineate the pathogenic potential of these antibodies.

Neuromyelitis Optica spectrum disorders in Argentina: A hospital-based study.

BACKGROUND: Neuromyelitis Optica spectrum disorder (NMOSD) is an antibody-mediated autoimmune disease of the CNS, which especially affects the optic nerves and spinal cord. There is little known in Latin America (LATAM) about NMOSD, and few reports have been published in the literature so far. We aimed to describe an NMOSD study in a single center from Argentina. METHODS: A retrospective cross sectional study was carried out in a single reference center in the city of Buenos Aires, Argentina. Data were collected from January 2000 through December 2021 using medical records from patients attending Ramos Mejia Hospital in Buenos Aires, Argentina. Here we describe the clinical, laboratory, MRI, disability course, and treatment of 92 NMOSD patients. RESULTS: Mean age at the onset of symptoms was 31 years (range 2-68) with a female/male ratio of 4.8:1. 71.7 % had an early onset before the age of 50 years old, 8.7 % had a late onset of the disease and 19.6 % had an onset at pediatric age. The first symptom of NMOSD was optic neuritis in 47.8 % of the patients, followed by transverse myelitis, 33.7 % and area postrema syndrome, 5.4 %. 96.7 % of patients relapsed at least once during the follow-up period. The mean of the expanded disability status scale (EDSS) was 4.0 (range 2-8). 34,8 % had one or more associated autoimmune diseases. 78,6 % had a positive result for AQP4-IgG. The ratio of male to female was 1:8.4 vs.1:1.2 in the seropositive group vs. the seronegative. CSF results showed OCB type 2 in 6.3 %. The brain MRI did not show brain lesions in 71,7 % of the patients. 17 % presented spinal cord lesions with less than 3 vertebral segments. All patients received treatment with immunosuppressive drugs. Rituximab and azathioprine were the most used. CONCLUSIONS: This is the largest hospital-based study in an Argentina cross-sectional study of patients with NMOSD. Recurrent disease, early age at onset, female prevalence in AQP4-IgG+ patients, and the difficulty to assess new treatments, are the highlight features in our study of patients. Further Argentinian and LATAM studies will provide more information.

Population Pharmacodynamic Modelling of the CD19+ Suppression Effects of Rituximab in Paediatric Patients with Neurological and Autoimmune Diseases.

BACKGROUND: Limited pharmacotherapy and the failure of conventional treatments in complex pathologies in children lead to increased off-label use of rituximab. We aimed to characterize the time course of CD19+ B lymphocytes (CD19+) under treatment with intravenous rituximab in children with neurologic and autoimmune diseases and to evaluate the impact of covariates (i.e., demographics, diagnosis and substitution between innovator and biosimilar product) on rituximab pharmacodynamics and disease activity. METHODS: Pre- and post-drug infusion CD19+ in peripheral blood were prospectively registered. A population pharmacodynamic model describing the time course of CD19+ was developed with NONMEM v7.4. Simulations of three different rituximab regimens were performed to assess the impact on CD19+. Logistic regression analysis was performed to identify predictors of clinical response recorded through disease activity scores. RESULTS: 281 measurements of CD19+ lymphocyte counts obtained from 63 children with neurologic (n = 36) and autoimmune (n = 27) diseases were available. The time course of CD19+ was described with a turn-over model in which the balance between synthesis and degradation rates is disrupted by rituximab, increasing the latter process. The model predicts half-lives (percent coefficient of variation, CV(%)) of rituximab and CD19+ of 11.6 days (17%) and 173.3 days (22%), respectively. No statistically significant effect was found between any of the studied covariates and model parameters (p > 0.05). Simulations of different regimens showed no clinically significant differences in terms of CD19+ repopulation times. A trend towards a lack of clinical response was observed in patients with lower CD19+ repopulation times and higher areas under the CD19+ versus time curve. CONCLUSIONS: Rituximab pharmacodynamics was described in a real-world setting in children suffering from autoimmune and neurologic diseases. Diagnosis, substitution between innovator rituximab and its biosimilars or type of regimen did not affect rituximab-induced depletion of CD19+ nor the clinical response in this cohort of patients. According to this study, rituximab frequency and dosage may be chosen based on clinical convenience or safety reasons without affecting CD19+ repopulation times. Further studies in larger populations are required to confirm these results.

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

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

Treatment of acute disseminated encephalomyelitis.

OPINION STATEMENT: Acute disseminated encephalomyelitis (ADEM) is an inflammatory demyelinating disease, characterized by an acute onset of polyfocal central nervous system (CNS) deficits, including encephalopathy, demonstrating multifocal lesions on MRI. ADEM is typically a monophasic disorder, but recurrent and multiphasic courses have been described. Furthermore, an ADEM presentation has been reported in neuromyelitis optica (NMO) and multiple sclerosis (MS), particularly in younger children. CNS infections, other autoimmune diseases, and neurometabolic disorders may mimic ADEM at manifestation. There is no single test confirming the diagnosis of ADEM, and diagnosis is based upon a combination of clinical and radiologic features and exclusion of diseases that resemble ADEM. Therefore, a broad workup including infectious, immunologic, and metabolic tests, as well as a systematic follow-up including MRI, is indicated to establish an accurate diagnosis as a prerequisite for an optimized treatment approach. There is a lack of evidence-based, prospective clinical trial data for the management of ADEM. Empiric antibacterial and antiviral treatment is standard of care until an infectious disease process is ruled out. Based on the presumed autoimmune etiology of ADEM, the common treatment approach consists of intravenous methylprednisolone at a dosage of 20 to 30 mg/kg per day (maximum 1 g/day) for 3 to 5 days, followed by an oral corticosteroid taper of 4 to 6 weeks. In case of insufficient response or contraindications to corticosteroids, intravenous immunoglobulin G (IVIG) at a dosage of 2 g/kg divided over 2 to 5 days is a therapeutic option. For severe or life-threatening cases of ADEM, plasmapheresis should be considered early in the disease course. Decompressive craniectomy has been reported as a life-saving measure for ADEM patients with intracranial hypertension. There is a lack of specific recommendations for the long-term management of recurrent and multiphasic ADEM. In children with relapsing demyelinating events, the diagnosis of a chronic autoimmune CNS disease like MS or NMO should be considered.

Age-dependent B cell autoimmunity to a myelin surface antigen in pediatric multiple sclerosis.

Multiple sclerosis (MS) typically manifests in early to mid adulthood, but there is increasing recognition of pediatric-onset MS, aided by improvements in imaging techniques. The immunological mechanisms of disease are largely unexplored in pediatric-onset MS, in part because studies have historically focused on adult-onset disease. We investigated autoantibodies to myelin surface Ags in a large cohort of pediatric MS cases by flow cytometric labeling of transfectants that expressed different myelin proteins. Although Abs to native myelin oligodendrocyte glycoprotein (MOG) were uncommon among adult-onset patients, a subset of pediatric patients had serum Abs that brightly labeled the MOG transfectant. Abs to two other myelin surface Ags were largely absent. Affinity purification of MOG Abs as well as competition of binding with soluble MOG documented their binding specificity. Such affinity purified Abs labeled myelin and glial cells in human CNS white matter as well as myelinated axons in gray matter. The prevalence of such autoantibodies was highest among patients with a very early onset of MS: 38.7% of patients less than 10 years of age at disease onset had MOG Abs, compared with 14.7% of patients in the 10- to 18-year age group. B cell autoimmunity to this myelin surface Ag is therefore most common in patients with a very early onset of MS.

Intensive Safety Monitoring of Rituximab (Biosimilar Novex® and the Innovator) in Pediatric Patients With Complex Diseases.

Although rituximab is widely used off-label for complex pediatric diseases, safety reports are limited. We aimed to report evidence of its use in clinical practice, to describe the incidence of adverse drug reactions (ADR) to rituximab biosimilar Novex® and innovator, and to identify risk factors for the development of ADR in a real-life follow-up cohort of pediatric patients with complex diseases. We conducted a prospective, longitudinal, observational, single-centre study in patients that received rituximab for any complex disease, and as part of an intensive pharmacovigilance program. Demographic, pharmacological, clinical, and drug-related data were collected for all patients. ADR-free survival, including infusion-related reactions (IRR) and delayed ADR (dADR), was estimated using Kaplan-Meier curves. Risk factors were evaluated by multivariable Cox regression models. In total, 77 patients (<19 y.o.) received 187 infusions of rituximab Novex® (n = 155) or innovator rituximab (n = 32) for neurologic (Neu), immune-hematologic-rheumatic (IHR), oncologic (O) diseases, and hematopoietic stem-cell transplantation (HSCT) or solid-organ transplantation (SOT). We recorded 29 IRR and 58 dADR that occurred in 27 (35.1%) and 29 (37.7%) patients, respectively. The respiratory tract was the most affected during IRR (29.6%) and hypogammaglobulinemia (37.9 %) was the most frequent dADR. First versus subsequent infusions (HR 5.4, CI95% 2.4-12.1, p<0.05), sex (boys vs. girls, HR 0.3, CI95% 0.1-0.8, and p<0.05), and diagnosis (Neu-IHR diseases vs. O-HSCT-SOT, HR 2.3, CI95% 1.02-5.4, and p < 0.05) were significantly associated with the development of IRR. For dADR, risk factors were diagnosis (Neu-IHR diseases vs. O-HSCT-SOT, HR 0.4, CI95% 0.2-0.9, and p < 0.05) and cumulative body surface area-normalized dosage (HR 1.0003, CI95% 1.0001-1.0006, and p < 0.05). The present is the largest real-world safety assessment of rituximab in Latin-American children with complex diseases supporting its use based on the overall acceptable safety. Identification of risk factors may contribute to optimization of off-label rituximab treatment in pediatrics.

Use and Safety of Immunotherapeutic Management of N-Methyl-d-Aspartate Receptor Antibody Encephalitis: A Meta-analysis.

Importance: Overall, immunotherapy has been shown to improve outcomes and reduce relapses in individuals with N-methyl-d-aspartate receptor (NMDAR) antibody encephalitis (NMDARE); however, the superiority of specific treatments and combinations remains unclear. Objective: To map the use and safety of immunotherapies in individuals with NMDARE, identify early predictors of poor functional outcome and relapse, evaluate changes in immunotherapy use and disease outcome over the 14 years since first reports of NMDARE, and assess the Anti-NMDAR Encephalitis One-Year Functional Status (NEOS) score. Data Sources: Systematic search in PubMed from inception to January 1, 2019. Study Selection: Published articles including patients with NMDARE with positive NMDAR antibodies and available individual immunotherapy data. Data Extraction and Synthesis: Individual patient data on immunotherapies, clinical characteristics at presentation, disease course, and final functional outcome (modified Rankin Scale [mRS] score) were entered into multivariable logistic regression models. Main Outcomes and Measures: The planned study outcomes were functional outcome at 12 months from disease onset (good, mRS score of 0 to 2; poor, mRS score greater than 2) and monophasic course (absence of relapse at 24 months or later from onset). Results: Data from 1550 patients from 652 articles were evaluated. Of these, 1105 of 1508 (73.3%) were female and 707 of 1526 (46.3%) were 18 years or younger at disease onset. Factors at first event that were significantly associated with good functional outcome included adolescent age and first-line treatment with therapeutic apheresis, corticosteroids plus intravenous immunoglobulin (IVIG), or corticosteroids plus IVIG plus therapeutic apheresis. Factors significantly associated with poor functional outcome were age younger than 2 years or age of 65 years or older at onset, intensive care unit admission, extreme delta brush pattern on electroencephalography, lack of immunotherapy within the first 30 days of onset, and maintenance IVIG use for 6 months or more. Factors significantly associated with nonrelapsing disease were rituximab use or maintenance IVIG use for 6 months or more. Adolescent age at onset was significantly associated with relapsing disease. Rituximab use increased from 13.5% (52 of 384; 2007 to 2013) to 28.3% (311 of 1100; 2013 to 2019) (P < .001), concurrent with a falling relapse rate over the same period (22% [12 of 55] in 2008 and earlier; 10.9% [35 of 322] in 2017 and later; P = .006). Modified NEOS score (including 4 of 5 original NEOS items) was associated with probability of poor functional status at 1 year (20.1% [40 of 199] for a score of 0 to 1 points; 43.8% [77 of 176] for a score of 3 to 4 points; P = .05). Conclusions and Relevance: Factors influencing functional outcomes and relapse are different and need to be considered independently in development of evidence-based optimal management guidelines of patients with NMDARE.

International Consensus Recommendations for the Treatment of Pediatric NMDAR Antibody Encephalitis.

OBJECTIVE: To create an international consensus treatment recommendation for pediatric NMDA receptor antibody encephalitis (NMDARE). METHODS: After selection of a panel of 27 experts with representation from all continents, a 2-step Delphi method was adopted to develop consensus on relevant treatment regimens and statements, along with key definitions in pediatric NMDARE (disease severity, failure to improve, and relapse). Finally, an online face-to-face meeting was held to reach consensus (defined as ≥75% agreement). RESULTS: Corticosteroids are recommended in all children with NMDARE (pulsed IV preferred), with additional IV immunoglobulin or plasma exchange in severe patients. Prolonged first-line immunotherapy can be offered for up to 3-12 months (oral corticosteroids or monthly IV corticosteroids/immunoglobulin), dependent on disease severity. Second-line treatments are recommended for cases refractory to first-line therapies (rituximab preferred over cyclophosphamide) and should be considered about 2 weeks after first-line initiation. Further immunotherapies for refractory disease 1-3 months after second-line initiation include another second-line treatment (such as cyclophosphamide) and escalation to tocilizumab. Maintenance immune suppression beyond 6 months (such as rituximab redosing or mycophenolate mofetil) is generally not required, except for patients with a more severe course or prolonged impairments and hospitalization. For patients with relapsing disease, second-line and prolonged maintenance therapy should be considered. The treatment of NMDARE following herpes simplex encephalitis should be similar to idiopathic NMDARE. Broad guidance is provided for the total treatment duration (first line, second line, and maintenance), which is dictated by the severity and clinical course (i.e., median 3, 9 and 18 months in the best, average, and worst responders, respectively). Recommendations on the timing of oncologic searches are provided. CONCLUSION: These international consensus recommendations for the management of pediatric NMDARE aim to standardize the treatment and provide practical guidance for clinicians, rather than absolute rules. A similar recommendation could be applicable to adult patients.

Emerging concepts in pediatric-onset multiple sclerosis and related disorders.

PURPOSE OF REVIEW: Pediatric-onset multiple sclerosis (MS) is increasingly recognized. Conversely, MS diagnosis in the pediatric population continues to be challenging, particularly in the youngest group of patients. An interesting amount of data has been recently published concerning immunopathogenesis, environmental factors, diagnosis, and treatment of MS in pediatric patients. RECENT FINDINGS: Recent studies have demonstrated that brain MRI criteria may distinguish MS from acute disseminated encephalomyelitis, and from nondemyelinating disorders in children. The presence of native myelin oligodendrocyte glycoprotein antibodies strongly correlates with a particular pediatric MS phenotype. Vitamin D, Epstein-Barr virus infection, and cigarette smoke are risk factors likely to act at specific stages during life. Diffuse tissue damage was confirmed in normal-appearing white matter at early stages of disease in children with MS, pointing to the need for early treatment interventions. The cognitive involvement of MS in children is progressive. SUMMARY: Pediatric-onset MS needs a prompt identification and early treatment. Further multinational research studies are still necessary to advance on genetic, immunologic, and imaging features on the initial and ongoing aspects of this disorder in the pediatric population.

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

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

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

[This corrects the article DOI: 10.3389/fped.2020.00339.].

Clinical trials of disease-modifying agents in pediatric MS: Opportunities, challenges, and recommendations from the IPMSSG.

OBJECTIVE: The impetus for this consensus discussion was to recommend clinical trial designs that can deliver high-quality data for effective therapies for pediatric patients, in a reasonable timeframe, with a key focus on short- and long-term safety. METHODS: The International Pediatric Multiple Sclerosis Study Group convened a meeting of experts to review the advances in the understanding of pediatric-onset multiple sclerosis (MS) and the advent of clinical trials for this population. RESULTS: In the last few years, convincing evidence has emerged that the biological processes involved in MS are largely shared across the age span. As such, treatments proven efficacious for the care of adults with MS have a biological rationale for use in pediatric MS given the relapsing-remitting course at onset and high relapse frequency. There are also ethical considerations on conducting clinical trials in this age group including the use of placebo owing to highly active disease. It is imperative to reconsider study design and implementation based on what information is needed. Are studies needed for efficacy or should safety be the primary goal? Further, there have been major recruitment challenges in recently completed and ongoing pediatric MS trials. Phase 3 trials for every newly approved therapy for adult MS in the pediatric MS population are simply not feasible. CONCLUSIONS: A primary goal is to ensure high-quality evidence-based treatment for children and adolescents with MS, which will improve our understanding of the safety of these agents and remove regulatory or insurance-based limitations in access to treatment.

Prognostic indicators of improvement with therapeutic plasma exchange in pediatric demyelination.

OBJECTIVES: To determine the safety and clinical benefit of therapeutic plasma exchange (TPE) as rescue therapy in children with acute inflammatory demyelinating CNS syndromes and to identify baseline prognostic indicators of treatment improvement. METHODS: This single-center retrospective pediatric cohort included all consecutive patients admitted to our hospital over the period from 2003 to 2017 because of a steroid-refractory acute CNS event presumed to be inflammatory who required TPE. Functional status assessment to identify improvement included the following performance category scales: visual outcome, bladder control, gait, and Expanded Disability Status Scale (EDSS). These assessments were performed before and after TPE in every patient. RESULTS: Sixty-five children requiring TPE to treat 78 CNS attacks were included for analysis. Median age at TPE was 10.5 years (1.9-18 years); 45% were girls. Seropositivity (aquaporin-4 water channel-immunoglobulin G [IgG] or myelin oligodendrocyte glycoprotein-IgG) was found in 20 of 42 (48%) patients. Attack phenotypes leading to TPE were optic neuritis (ON) in 42%, longitudinally extensive transverse myelitis (LETM) in 31%, ON + LETM in 15%, and other combined syndromes in 11%. Overall, moderate to marked neurologic improvement was observed in 72% of children at the end of TPE and in 88.5% at 6 months of follow-up. Lower baseline scores on the EDSS, visual outcome, and gait scales were found to be independent prognostic indicators of treatment benefit. Sex, age at onset and at TPE, attack phenotype, disease duration, and time from attack onset to TPE initiation were not significantly associated with treatment outcome. Adverse events were observed in 31 of 524 (5.9%) procedures, being severe in 4. CONCLUSIONS: TPE was an effective rescue therapy associated with functional improvement. No therapeutic window for TPE initiation was identified in this pediatric cohort. Overall frequency of adverse events was low; however, serious events should be anticipated and avoided. CLASSIFICATION OF EVIDENCE: This study provides Class IV evidence that for children with acute inflammatory demyelinating CNS syndromes, TPE leads to functional improvement.