Search

Objective: Susac syndrome (SuS), multiple sclerosis (MS), and primary angiitis of the central nervous system (PACNS) present diagnostic challenges due to overlapping clinical features. We aimed to enhance diagnostic precision by developing the SPAMS (SuS, PACNS, MS) score, a practical radiological tool., Methods: This multicenter study included 99 patients (43 SuS, 37 MS, 19 PACNS) from South American countries. Relevant MRI features were identified through an elastic-net model determined key variables., Results: The SPAMS score assigned 2 points for snowball lesions, 1 point for spokes-like lesions, or if there are more than 4 lesions in the corpus callosum, corpus callosum involvement, or cerebellar involvement. It subtracted 1 point if gadolinium-enhancing lesions or 4 points if Dawson's fingers are present. Bootstrapping validated the optimal cutoff at 2 points, exhibiting a diagnostic performance of area under the curve = 0.931, sensitivity = 88%, specificity = 89%, positive predictive value = 88%, negative predictive value = 89%, and accuracy = 88%., Interpretation: When specific MRI findings coexisted, the SPAMS score differentiated SuS from MS and PACNS. Access to MRI and standard protocol sequences makes it a valuable tool for timely diagnosis and treatment, potentially preventing disability progression and severe clinical outcomes. ANN NEUROL 2024;96:846-854., (© 2024 American Neurological Association.)

Background: Leukocyte telomere length (LTL) shortens with age and may be related to multiple sclerosis (MS)., Objective: We hypothesize that chronologically young people with MS (pwMS) with short LTL behave similarly to older MS subjects., Methods: Prospective 2-year study including two cohorts of young (18-35 years) and elderly (⩾50 years) pwMS with similar disease duration. Physical and cognitive evaluation, 3 T brain magnetic resonance imaging (MRI) and retinal nerve fiber layer (RNFL) measurement by optical coherence tomography were performed. LTL was measured by quantitative polymerase chain reaction assay., Results: Around 105 patients were included, 57 young and 48 elderly. LTL was shorter in older patients (0.61 versus 0.57, p = 0.0081) and in males (female, 0.60; male, 0.59; p = 0.01335). For every 10-year increase in age, LTL was 0.02 U shorter. In elderly, LTL correlated with disease duration ( p = 0.05), smoking ( p = 0.03), Expanded Disability Status Scale (EDSS; p = 0.004), 9HPT ( p = 0.00007), high-efficacy therapies ( p = 0.001), brain lesion volume (BLV) ( p = 0.011), and number of T2 lesions ( p = 0.01). In young patients, LTL did not correlate with clinical or radiological variables. For every 0.1 U shorter LTL, gray matter volume decreased 1.75 cm 3 and white matter volume 1.78 cm 3 ., Conclusion: LTL correlated with disability and BLV in elderly. Besides LTL shortening, other variables should be considered as mechanisms of neurodegeneration that might be involved in aging pwMS., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Background: Immunosuppressive therapies as azathioprine (AZA), mycophenolate mofetil (MMF) and rituximab (RTX) are widely prescribed as first-line treatment to prevent relapses in NMOSD. However, the rate of response to these traditional therapies is unknown in Argentina. We aimed to describe and compare treatment failure rates in NMOSD patients included in the Argentinean MS and NMOSD registry (RelevarEM, NCT03375177)., Methods: A retrospective cohort study was conducted in NMOSD patients included in RelevarEM (a nationwide, longitudinal, observational, non-mandatory registry of MS and NMOSD in Argentina). NMOSD patients were defined based on validate diagnostic criteria. Only NMOSD patients who received AZA or MMF for at least 6 months or RTX for at least 1 month were included. Patients who were receiving AZA, MMF, or RTX and then switched to another 1 of these 3 therapies were included if the above-mentioned criteria for each drug were fulfilled. Data on patient demographics, clinical, neuroradiological findings, and treatments administered were collected. Treatment failure was defined as any new attack/relapse that occurred despite immunosuppressive treatment., Results: We included 139 NMOSD patients who were receiving AZA (n = 105), MMF (n = 5) or RTX (n = 29) with a mean follow-up time of 41.3 ± 11.4 months and median of EDSS at treatment initiation of 3. We observed a reduction in the annualized relapse rate from pre-treatment to post-treatment of 51.1 %, 48.4 %, and 79.1 % respectively with a Hazard Risk relative to RTX (95 % CI) of 1.67 (1.34-3.54, p = 0.01) for AZA and 2.01 (1.86-4.43, p = 0.008) for MMF. AZA, MMF and RTX failure was observed in 45/105 (42.8 %), 2/5 (40 %) and 3/29 (10.3 %) patients, respectively., Conclusions: Treatment failure rates were higher for AZA and MMF than RTX in Argentinean NMOSD patients in a real-world setting. High-efficacy treatment increases the opportunity to prevent attacks of NMOSD., Competing Interests: Declaration of competing interest The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Background: Knowledge of the safety and efficacy of disease-modifying therapies (DMTs) in older patients with Multiple Sclerosis (pwMS) is limited due to their exclusion from clinical trials. Our purpose is to evaluate the choice of DMTs in pwMS older than 50 years old in a real-world setting., Methods: Cross-sectional study of pwMS from the Argentine MS and NMOSD Registry. We included patients under 35 and above 50 years old prescribed DMTs. Disease activity was categorized as highly active (HA) or not highly active (NHA), and DMTs were classified as low efficacy therapies (LET) or high efficacy therapies (HET)., Results: 1460 patients (65% females) were enrolled. The HA group comprised 241 patients, 198 young (82.2%) and 43 older (17.8%). The NHA group included 1219 patients, 893 young (73%) and 326 older (27%). In the NHA group, older patients received LET more frequently than younger patients (66% versus 44%; p < 0.01). In the HA group, older patients received LET in 61% of cases, whereas younger patients received HET in 71% (p = 0.01)., Conclusion: The study shows the preference of LET in older patients regardless of disease activity. However it does not demonstrate a difference in disability in older patients based on low vs high efficacy DMTs used, probably due to the design of the study. Further longitudinal studies are warranted to address this issue., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Background: Most Multiple Sclerosis (MS) clinical trials fail to assess the long-term effects of disease-modifying therapies (DMT) or disability., Methods: COLuMbus was a single-visit, cross-sectional study in Argentina in adult patients with ≥10 years of MS since first diagnosis. The primary endpoint was to determine patient disability using the Expanded Disability Status Scale (EDSS). The secondary endpoints were to evaluate the distribution of diagnoses between relapsing-remitting MS (RRMS) and secondary progressive MS (SPMS), patient demographics, disease history, and the risk of disability progression. The relationship between baseline characteristics and the current disability state and the risk of disability progression was assessed., Results: Out of the 210 patients included, 76.7 % had a diagnosis of RRMS and 23.3 % had been diagnosed with SPMS, with a mean disease duration of 17.9 years and 20.5 years, respectively. The mean delay in the initial MS diagnosis was 2.6 years for the RRMS subgroup and 2.8 years for the SPMS subgroups. At the time of cut-off (28May2020), 90.1 % (RRMS) and 75.5 % (SPMS) of patients were receiving a DMT, with a mean of 1.5 and 2.0 prior DMTs, respectively. The median EDSS scores were 2.5 (RRMS) and 6.5 (SPMS). In the RRMS and SPMS subgroups, 23 % and 95.9 % of patients were at high risk of disability, respectively; the time since first diagnosis showed a significant correlation with the degree of disability., Conclusions: This is the first local real-world study in patients with long-term MS that highlights the importance of recognizing early disease progression to treat the disease on time and delay disability., Competing Interests: Declaration of competing interest Norma Deri reports grants from Novartis Argentina S.A. during the conduct of the study; grants from Novartis Argentina S.A., Sanofi Aventis and Laboratorios Roche not related to the submitted work. Andres Barboza reports grants from Novartis Argentina S.A. during the conduct of the study. Carlos Vrech reports grants from Novartis Argentina S.A. during the conduct of the study, and personal fees from Merck not related to the submitted work. Roberto Rey reports grants from Novartis Argentina S.A. during the conduct of the study. Marcos Burgos reports grants or contracts from Novartis Argentina S.A. and Biogen not related to the submitted work, personal fees/honoraria, and meeting travel support from Novartis Argentina S.A., Biogen, Teva, Merck and Roche. Marcela Fiol reports grants from Novartis Argentina S.A. during the conduct of the study, and grants from Biogen not related to the submitted work. Liliana Patrucco reports grants from Novartis Argentina S.A. during the conduct of the study, personal fees from Novartis Argentina S.A., Roche, Sanofi-Genzyme, Biogen, Merck, and Biosidus not related to the submitted work. Cristian Calvo-Vildoso reports no conflicts of interest. Gustavo Jose reports personal fees, non-financial support and other from Novartis Argentina S.A. during the conduct of the study, and grants and other from Novartis Argentina S.A. and Amgen not related to the submitted work. Paula Aliberti, Daniela Chirico, Maria B. Federico are employees at Novartis Argentina S.A. Gustavo Seifer was an employee at Novartis Argentina SA at the time of the study. Raul Piedrabuena reports grants from Novartis Argentina S.A. during the conduct of the study, grants from Biogen and Merck, personal fees from Roche, Merck, and Sanofi Genzyme not related to the submitted work., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Objectives: To study different components of social cognition and quality of life in patients with early multiple sclerosis and low Expanded Disability Status Scale and to test the influence of cognitive performance, fatigue and neuropsychiatric symptoms on social cognition performance., Methods: Thirty-four patients with relapsing-remitting MS, with ≤2 years of disease duration and scores ≤2 on the EDSS and 30 healthy controls underwent neuropsychological assessment with the Brief Repeatable Neuropsychological Test Battery. Components of social cognition, such as emotion recognition, theory of mind, empathy, and emotional reactivity, were assessed with the Reading the Mind in the Eyes test, the Faux Pas task, the International Affective Imagery System, and the Empathy Quotient. Anxiety, depression, fatigue and quality of life were measured., Results: Patients showed significant differences in verbal memory, executive functions and social cognition, especially emotion recognition and ToM. Regarding emotional reactivity, patients showed a positive bias in the interpretation of the valence of neutral images., Conclusions: Patients with early MS showed impairments in several components of social cognition independent of cognitive performance, neuropsychiatric symptoms and fatigue. Social cognition deficits may be present in MS even in the early stages.

Background and Purpose: Serum levels of neurofilament light chain (sNfL) and glial fibrillary acidic protein (sGFAP) are promising neuro-axonal damage and astrocytic activation biomarkers. Susac syndrome (SS) is an increasingly recognized neurological condition and biomarkers that can help assess and monitor disease evolution are highly needed for the adequate management of these patients. sNfL and sGFAP levels were evaluated in patients with SS and their clinical relevance in the relapse and remission phase of the disease was assessed., Methods: As part of a multicentre study that enrolled patients diagnosed with SS from six international centres, sNfL and sGFAP levels were assessed in 22 SS patients (nine during a relapse and 13 in remission) and 59 age- and sex-matched healthy controls using SimoaTM assay Neurology 2-Plex B Kit., Results: Serum NfL levels were higher than those of healthy controls (p < 0.001) in SS patients and in both subgroups of patients in relapse and in remission (p < 0.001 for both), with significantly higher levels in relapse than in remission (p = 0.008). sNfL levels showed a negative correlation with time from the last relapse (r = -0.663; p = 0.001). sGFAP levels were slightly higher in the whole group of patients than in healthy controls (p = 0.046) and were more pronounced in relapse than in remission (p = 0.013)., Conclusion: In SS patients, both sNFL and sGFAP levels increased compared with healthy controls. Both biomarkers had higher levels during clinical relapse and much lower levels in remission. sNFL was shown to be time sensitive to clinical changes and can be useful to monitor neuro-axonal damage in SS., (© 2023 The Authors. European Journal of Neurology published by John Wiley & Sons Ltd on behalf of European Academy of Neurology.)

Background: Information on performance of multiple sclerosis (MS) diagnostic criteria is scarce for populations from Latin America, Asia, or the Caribbean., Objective: To assess performance of revised 2017 McDonald criteria as well as evaluate genetic ancestry in a group of MS patients from Argentina experiencing a debut demyelinating event., Methods: Demographic and clinical characteristics, cerebrospinal fluid (CSF), and magnetic resonance imaging (MRI) findings and new T2 lesions were recorded at baseline and during relapses. Diagnostic accuracy in predicting conversion to clinically defined MS (CDMS) based on initial imaging applying revised 2017 criteria was evaluated and genetic ancestry-informative markers analyzed., Results: Of 201 patients experiencing their first demyelinating event (median follow-up 60 months), CDMS was confirmed in 67. We found 2017 diagnostic criteria were more sensitive (84% vs 67%) and less specific (14% vs 33%) than 2010 criteria, especially in a group of patients revised separately, presenting positive oligoclonal bands (88% vs 8%). Genetic testing performed in 128 cases showed 72% of patients were of European ancestry and 27% presented genetic admixture., Conclusion: 2017 McDonald criteria showed higher sensitivity and lower specificity compared with 2010 criteria, shortening both time-to-diagnosis and time-to-treatment implementation.

The objective was to evaluate time to reach an EDSS of 4, 6, and 7 in NMOSD and MOGAD patients included in the Argentinean MS and NMOSD registry (RelevarEM, NCT 03,375,177)., Methods: NMOSD patients diagnosed according to 2015 criteria and with MOGAD were identified. Patients with at least 3 years of follow-up and periodic clinical evaluations with EDSS outcomes were included. AQP4-antibody and MOG-antibody status was recorded, and patients were stratified as seropositive and seronegative for AQP4-antibody. EDSS of 4, 6, and 7 were defined as dependent variables. Log rank test was used to identify differences between groups., Results: Registry data was provided for a total of 137 patients. Of these, seventy-five presented AQP4-ab-positive NMOSD, 45 AQP4-ab-negative NMOSD, and 11 MOGAD. AQP4-ab status was determined by cell-based assay (CBA) in 72% of NMOSD patients. MOG-ab status was tested by CBA in all cases. Mean time to EDSS of 4 was 53.6 ± 24.5 vs. 63.1 ± 32.2 vs. 44.7 ± 32 months in seropositive, seronegative NMOSD, and MOGAD, respectively (p = 0.76). Mean time to EDSS of 6 was 79.2 ± 44.3 vs. 75.7 ± 48.6 vs. 54.7 ± 50 months in seropositive, seronegative NMOSD, and MOGAD (p = 0.23), while mean time to EDSS of 7 was 86.8 ± 54 vs. 80.4 ± 51 vs. 58.5 ± 47 months in seropositive, seronegative NMOSD, and MOGAD (p = 0.39)., Conclusion: No differences were observed between NMOSD (seropositive and seronegative) and MOGAD in survival curves., (© 2022. Fondazione Società Italiana di Neurologia.)

The objective of the study was to evaluate the incidence of COVID-19 after complete vaccination in people with multiple sclerosis (PwMS) included in the Argentinean MS and NMOSD registry (RelevarEM, NCT03375177)., Methods: cohort study conducted between May 2021 and December 2021. The primary outcome was the appearance of infection during the follow-up time (at least three months after complete vaccination (second dose)). Data was collected through the contact between the treating physician and the patient. Specific information was requested (date, symptoms, need for hospitalization, ventilatory assistance, treatment, and evolution). The contact was made every 30 days during the period of 3 months after the full dose vaccination. A positive COVID-19 case was defined according to the definition established by the Ministry of Health in Argentina. Cumulative incidence was reported by Kaplan Meier survival curves as well as incidence density., Results: A total of 576 PwMS were included, mean age 45.2 ± 13 years, 432 (75%) RRMS, 403 (70%) were female. The mean and median time of follow-up after the second dose was 91 ± 17 and 94 ± 21 days respectively. Most frequent first and second dose received was Astra-Zeneca vaccine, followed by Sputnik V vaccine. During follow-up a total of twenty COVID-19 cases were observed for a total exposure time of 39,557 days. The overall cumulative incidence for the observed period was 3.4% (SE 0.4%) with an overall incidence density of 5 × 10.000 patients/day (95%CI 0.7-12). We observed more cases in woman than men with an incidence density of 6 × 10.000 patients/day (95%CI 0.9-9) vs. 3 × 10.000 patients/day (95%CI 0.2-6) respectively, but not significantly different (IRR 1.7 95% CI 0.56-7.37 p = 0.15)., Conclusion: we found an incidence density of breakthrough COVID-19 infection of 5 × 10.000 patients/day (95%CI 0.7-12) after vaccination in Argentina., Competing Interests: Declaration of Competing Interest Authors declare no potential conflicts of interest regarding this research, authorship and/or publication of this article. We wish to confirm that there are no known conflicts of interest associated with this publication and there has been no significant financial support for this work that could have influenced its outcome, (Copyright © 2022 Elsevier B.V. All rights reserved.)

Objective: Most contemporary data concerning the frequency and causes of multiple sclerosis (MS) misdiagnosis are from North America and Europe with different healthcare system structure and resources than countries in Latin America. We sought to determine the frequency, and potential contributors to MS misdiagnosis in patients evaluated at an MS referral center in Argentina., Methods: The study was a retrospective medical record review. We included patients evaluated at the MS Clinic at Fleni between April 2013 and March 2021. Diagnoses prior to consultation, final diagnoses after consultation, demographic, clinical and paraclinical data, and treatment were extracted and classified., Results: Seven hundred thirty-six patients were identified. Five hundred seventy-two presented with an established diagnosis of MS and after evaluation, misdiagnosis was identified in 89 (16%). Women were at 83% greater risk of misdiagnosis ( p  = 0.034). The most frequent alternative diagnoses were cerebrovascular disease, radiological isolated syndrome (RIS), and headache. Seventy-four (83%) of misdiagnosed patients presented with a syndrome atypical for demyelination, 62 (70%) had an atypical brain magnetic resonance imaging (MRI), and 54 (61%) were prescribed disease-modifying therapy., Conclusion: Sixteen percent of patients with established MS were subsequently found to have been misdiagnosed. Women were at higher risk for misdiagnosis. Expert application of the McDonald criteria may prevent misdiagnosis and its associated morbidity and healthcare system cost.

Susac syndrome is a disorder thought to be mediated by an autoimmune response towards endothelial cells, leading to a characteristic clinical triad of encephalopathy, visual disturbances due to branch arterial occlusions and sensorineural hearing impairment. Although it is a rare disease, three reasons make it important. First, given its variable presentation, Susac syndrome is underdiagnosed. Second, it is considered an important differential diagnosis in different neurological, psychiatric, ophthalmological and hearing disorders, and consequently is frequently misdiagnosed. Third, in many cases, Susac syndrome is diagnosed and treated late, with significant irreversible sequelae including dementia, blindness and hearing loss. Neuropathology findings derived from both Susac syndrome patient tissue and novel transgenic mouse models indicate cytotoxic CD8+ T cells adhere to microvessels, inducing endothelial cell swelling, vascular narrowing and occlusion, causing microinfarcts. Anti-endothelial cell antibodies are present in serum in 25% of Susac syndrome patients, but it is unclear whether they are aetiologically related to the disease, or an epiphenomenon. The clinical triad comprising encephalopathy, branch arterial occlusions, and sensorineural hearing impairment is considered pathognomonic, although great variability is found in presentation and natural course of disease. At first evaluation, only 13-30% of patients exhibit the full clinical triad, making diagnosis difficult. Retinal fluorescein angiography, optic coherence tomography, MRI and tonal audiometry are helpful methods for diagnosing and monitoring disease activity during treatment. By contrast, there are no reliable objective immune markers to monitor disease activity. Immunosuppression is the current treatment, with high-dose corticosteroid therapy as the mainstay, but additional therapies such as intravenous immunoglobulins, cyclophosphamide, rituximab and mycophenolate mofetil are often necessary, because the disease can be devastating, causing irreversible organ damage. Unfortunately, low rates of disease, variability in presentation and paucity of objective biomarkers make prospective controlled clinical trials for Susac syndrome treatment difficult. Current immunosuppressive treatments are therefore based on empirical evidence, mainly from retrospective case series and expert opinion. In this review, we draw attention to the need to take consider Susac syndrome in the differential diagnosis of different neurological, psychiatric, ophthalmological and hearing disorders. Furthermore, we summarize our current knowledge of this syndrome, in reference to its pathophysiology, diagnosis and management, emphasizing the need for prospective and controlled studies that allow a better therapeutic approach., (© The Author(s) 2022. Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Introduction: We aimed to analyze the accumulative risk of MRI and OB factors for evolution from RIS to MS in subjects included in the Argentinean MS registry (NCT03375177)., Methods: RIS subjects were identified according to RIS diagnosis criteria. Subjects were longitudinally followed with clinical and MRI at intervals of 6 months. Time from RIS identification to the first clinical event was estimated using Kaplan-Meier. Multivariable Cox regression models were created to assess the independent predictive value of demographic characteristics, as well as clinical, OB and MRI data on time to the first clinical event. The single and increased risk factor of evolution of RIS was quantified., Results: A total of 88 RIS subjects, mean follow-up time 42 ± 4 months were included. 39 (44.3%) and 23 (26.1%) had a new MRI lesion or a clinical event, respectively, during the follow-up. OB (HR 5.9, 95% CI 1.29-10.1, p = 0.004), infratentorial lesions (HR 3.7, 95% CI 1.09-7.5) and spinal cord lesions (HR 5.3, 95% CI 1.4-8.2, p = 0.01) at RIS identification were independent predictors associated with a subsequent clinical event. The accumulative risk showed that when two of the three factors (OB, infratentorial or spinal cord lesions) were present the HR was 10.4, 95% CI 4.4-22, p < 0.001, and when three factors were present, it was HR 15.6, 95% CI 5.7-28, p < 0.001 for a relapse., Conclusion: The presence of three factors significantly increased the risk of clinical event; high-risk subjects should probably be managed by a different approach than those used for individuals without high-risk factors., (© 2021. Springer-Verlag GmbH Germany, part of Springer Nature.)

Background: In multiple sclerosis demographics there is a well-known female prevalence and male patients have been less specifically evaluated in clinical studies, though some clinical differences have been reported between sexes., Objective: The objective of this study was to assess clinical and demographic differences between male and female patients included in the national Argentine MS Registry-RelevarEM., Material and Methods: This study was observational, retrospective, and was based on the data of 3099 MS patients included as of 04 April 2021. The statistical analysis plan included bivariate analyses with the crude data and also after adjustment for the MS phenotype, further categorized as progressive-onset MS or relapsing-onset MS. In the adjusted analysis, the Mantel-Haenszel odds ratio was compared to the crude odds ratio, to account for the phenotype as a confounder., Results: The data from 1,074 (34.7%) men and 2,025 (65.3%) women with MS diagnosis were analysed. Males presented primary progressive disease two times more often than women (11% and 5%, respectively). In the crude analyses by sex, the presence of exclusively infratentorial lesions in the magnetic resonance imaging studies was more frequent in males than in females, but after adjustment by MS onset phenotype, such difference was only present in males with relapsing-onset MS (p = 0.00006). Similarly, worse Expanded Disability Status Scale scores were confirmed only in men with relapsing-onset disease after phenotype adjustment (p = 0.02)., Conclusion: We did not find any statistically significant clinical or demographic difference between sexes when the progressive MS phenotype was specifically considered. However, the differences we found between the clinical phenotypes are in line with the literature and highlight the importance of stratifying the analyses by sex and phenotype when designing MS studies., (Copyright © 2021 Elsevier B.V. All rights reserved.)

The objectives of the present study were to describe the frequency of aggressive multiple sclerosis (aMS) as well as to compare clinical and radiological characteristics in aMS and non-aMS patients included in RelevarEM (NCT03375177)., Methods: The eligible study population and cohort selection included adult-onset patients (≥18 years) with definite MS. AMS were defined as those reaching confirmed EDSS ≥ 6 within 5 years from symptom onset. Confirmation was achieved when a subsequent EDSS ≥ 6 was recorded at least six months later but within 5 years of the first clinical presentation. AMS and non-aMS were compared using the χ2 test for categorical and the Mann-Whitney for continuous variables at MS onset and multivariable analysis was performed using forward stepwise logistic regression with baseline characteristics at disease onset., Results: A total of 2158 patients with MS were included: 74 aMS and 2084 non-aMS. The prevalence of aMS in our cohort was 3.4% (95%CI 2.7-4.2). AMS were more likely to be male (p = 0.003), older at MS onset (p < 0.001), have primary progressive MS (PPMS) phenotype (p = 0.03), multifocal presentation (p < 0.001), and spinal cord as well as infratentorial lesions at MRI during disease onset (p = 0.004 and p = 0.002, respectively)., Conclusion: 3.4% of our patient population could be considered aMS. Men, patients older at symptom onset, multifocal presentation, PPMS phenotype, and spinal cord as well as brainstem lesions on MRI at clinical presentation all had higher odds of having aMS., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Background: Myelin oligodendrocyte glycoprotein antibodies (MOG-ab) have been described in aquaporin-4-antibodies(AQP4-ab)-negative neuromyelitis optica spectrum disorder (NMOSD) patients. We aimed to evaluate the percentage of AQP4-ab-negative NMOSD patients who are positive for MOG-ab in a cohort of Argentinean patients included in RelevarEM (Clinical Trials registry number NCT03375177)., Methods: RelevarEM is a longitudinal, strictly observational multiple sclerosis (MS) and NMOSD registry in Argentina. Of 3031 consecutive patients (until March 2020), 165 patients with phenotype of suspected NMOSD, whose relevant data for the purpose of this study were available, were included. Data on demographic, clinical, paraclinical and treatment in AQP4-ab (positive, negative and unknown) and MOG-ab (positive and negative) patients were evaluated., Results: A total of 165 patients (79 AQP4-Ab positive, 67 AQP4-Ab negative and 19 unknown) were included. Of these, 155 patients fulfilled the 2015 NMOSD diagnostic criteria. Of 67 AQP4-Ab-negative patients, 36 (53.7%) were tested for MOG-Ab and 10 of them (27.7%) tested positive. Serum AQP4-ab levels were tested by means of cell-based assay (CBA) in 48 (35.2%), based on tissue-based indirect immunofluorescence assays in 58 (42.6%) and enzyme-linked immunosorbent assay in 4 (2.9%). All MOG-ab were tested by CBA. Optic neuritis (90%) was the most frequent symptom at presentation and optic nerve lesions the most frequent finding (80%) in neuroimaging of MOG-ab-associated disease. Of these, six (60%) patients were under immunosuppressant treatments at latest follow-up., Conclusion: We observed that 27.7% (10/36) of the AQP4-ab-negative patients tested for MOG-ab were positive for this antibody, in line with results from other world regions., (Copyright © 2021. Published by Elsevier B.V.)

Background: Multiple sclerosis (MS) is the most common chronic immune-mediated neurological disorder in young adults, more frequently found in women than in men. Therefore, pregnancy-related issues have become an object of concern for MS professionals and patients. The aim of this work was to review the existing data to develop the first Argentine consensus for family planning and pregnancy in MS patients., Methods: A panel of expert neurologists from Argentina engaged in the diagnosis and care of MS patients met both virtually and in person during 2019 to carry out a consensus recommendation for family planning and pregnancy in MS. To achieve consensus, the procedure of the "formal consensus-RAND/UCLA method" was used., Results: Recommendations were established based on published evidence and expert opinion focusing on pre-pregnancy counseling, pregnancy, and postpartum issues., Conclusion: The recommendations of these consensus guidelines are intended to optimize the management and treatment of MS patients during their reproductive age in Argentina., Competing Interests: Declaration of Competing Interest Nora Fernández Liguori has received consulting fees from Biogen Argentina, Novartis Argentina and Genzyme Argentina, as a lecturer from Merck Argentina, Novartis Argentina, Genzyme Argentina and Biogen Argentina, and collaboration for attendance to national and international congresses from Biogen Argentina, Novartis Argentina, Merck Argentina, Bayer Argentina, Gador and Roche Argentina. Ricardo Alonso has received personal compensation for consulting, serving on a scientific advisory board, speaking, professional travel/accommodation stipends or other activities with Biogen Argentina, Genzyme Argentina, Merck Argentina, Novartis Argentina and Roche Argentina. María Eugenia Balbuena has received personal compensation for speaking from Roche, professional travel/accommodation stipends from Merck, Novartis and Teva and funding for research from Genzyme and Novartis. Andrés Barboza has received reimbursement for developing educational presentations, educational and research grants, consultation fees and travel stipends from Biogen, Sanofi, Merck, Roche, Novartis, Teva, Gador, Raffo, Biosidus and Synthon-Bagó. Santiago Bestoso has received personal compensation for speaking, professional travel/accommodation stipends or other activities from Merck, Biogen, Novartis, Gador and Genzyme. Marcos Burgos has received personal compensation for speaking from Merck, Novartis, Raffo, Sanofi Genzyme, Biogen, Roche and for research from Novartis and Biogen. Fernando Cáceres has received fees for being a member of advisory boards, for research, being a speaker and for traveling/accommodation for scientific medical meetings of the following companies: Novartis, Teva, Roche, Biogen, Sanofi Genzyme and Merck. Edgar Carnero Contentti has received personal compensation for consulting, serving on a scientific advisory board, speaking, professional travel/accommodation stipends or other activities with Biogen Argentina, Genzyme Argentina, Merck Argentina, Novartis Argentina, Teva Argentina, Roche Argentina and Bayer Argentina. Adriana Carrá has received personal compensation for consulting, serving on a scientific advisory board, speaking, professional travel/accommodation stipends or other activities with Bayer; Biogen; Biosidus; Genzyme; Merck; MS Synthon-Bago; Novartis; Roche; Teva, Tuteur. Edgardo Cristiano received consulting fees, funding for advisory boards and educational support from Biogen, Genzyme, Merck, Novartis and Roche. Norma Deri has received personal compensation for advisory boards for Bayer Argentina, Bayer Latinoamerica, Bayer Global, Merck Serono Argentina, Merck Serono Global, Genzyme Argentina, Genzyme Latinoamerica, Genzyme Global and Sanofi Global; for travel/ accommodation from Schering, Bayer, Serono, Merck Serono, Novartis, Biogen Idec, Teva-Tuteur, Teva and Roche; for research from Bayer Argentina, Biogen Idec Argentina,Genzyme Argentina, Novartis Argentina, Roche Argentina, Teva Argentina and Sanofi Argentina and for educational presentations from Bayer Argentina, Merck Serono Argentina and Genzyme Argentina. Marcela Fiol has received personal compensation for developing educational presentations, serving on a scientific advisory board from Merck-Serono Argentina, Sanofi Genzyme Argentina, TEVA-Tuteur Argentina and has received travel/accommodations stipends from Merck-Serono Argentina, Sanofi Genzyme Argentina, Biogen INC, Bayer Inc, Novartis, TEVA-Tuteur Argentina, ROCHE Argentina. María Inés Gaitán has received reimbursement for developing educational presentations, from Roche Argentina, Merck Argentina, Biogen Argentina, Sanofi-Genzyme Argentina, Bayer Inc Argentina and Novartis Argentina, and has received travel/accommodations stipends from Merck Argentina, Biogen Argentina, Roche Argentina, Novartis Argentina, and TEVA Argentina. Orlando Garcea has received personal compensation for consulting and speaking from Bayer, Merck, Biogen, Novartis and Genzyme. Mario Javier Halfon has received personal compensation for consulting, serving on a scientific advisory board, speaking, professional travel/accommodation stipends or other activities from Biogen Argentina, Merck Argentina, Roche, Gador, Novartis, and Genzyme Argentina. Javier Hryb has received honoraria for the development of educational activities, and travel grants to congresses from Teva, Merck, Biogen, Roche, Tuteur, Synthon Bago and Novartis. Miguel Jacobo has received honoraria for the development of educational activities, research and travel grants to congresses from Biogen, Roche, Merck, Genzyme Novartis, Teva, Bayer, Raffo and Gador. Eduardo Knorre has received personal compensation for professional travel/accommodation stipends or other activities from Bagó, Tuteur and Roche. Pablo López has received personal compensation for consulting, serving on scientific advisory boards, speaking, professional travel/accommodation stipends or other activities with Biogen, Genzyme, Merck-Serono, Novartis, Teva, Roche and Bayer. Jimena Miguez has received personal compensation for professional travel/accommodation stipends or other activities from Merck, Novartis, Genzyme, Roche and for speaking from Merck, Novartis and Roche. Pedro Nofal has received honoraria for the development of educational activities, research and travel grants to congress from Novartis, Biogen, Merck Serono, Raffo, Genzyme, Gador and Bayer Schering. Raúl Piedrabuena has received personal compensation for the development of educational activities, serving on a scientific advisory board and research from Biogen, Merck, Novartis, Genzyme, Roche and Teva. Cecilia Pita has received honoraria for the development of educational activities, research and travel grants to congress from Biogen, Genzyme, Merck, Novartis and Roche. Juan Ignacio Rojas has received reimbursement for developing educational presentations, educational and research grants, consultation fees and travel stipends from Biogen, Genzyme, Merck, Novartis. Berenice Silva has received economic retribution for the development of educational, scientific activities and travel grants to congresses from Biogen, Novartis, Merck, Genzyme, TEVA, Bayer, Tuteur and Roche. Vladimiro Sinay has received personal compensation for consulting, serving on a scientific advisory board, speaking, professional travel/accommodation stipends or other activities with Bayer, Biogen, Genzyme, Merck, Novartis, Roche, Biosidus, Gador, Tuteur and Raffo/ Asofarma. Adriana Tarulla reports personal fees for speaking and support for travel to meetings from Bayer,Biogen Idec,Biosidus,Gador,Ivax-Teva,Merck Serono and Roche, out-side the submitted work. Darío Tavolini has received personal compensation for consulting, serving on a scientific advisory board, speaking, professional travel/accommodation stipends or other activities Bayer, Biogen, Genzyme, Merck Serono, Novartis, Roche and Teva. Santiago Tizio has received professional travel accommodation stipends from Merck-Serono, Synthon Bago, Biogen-Idec, TEVA, Genzyme, Novartis and Roche; reimbursement for developing educational presentations from Biogen-Idec and Novartis and honoraria for advisory services from Merck-Serono, and Novartis. Verónica Tkachuk: has received personal compensation for consulting, serving on a scientific advisory board, speaking, professional travel/accommodation stipends or other activities from Biogen, Roche, Merck, TEVA, Sanofi Genzyme, Novartis, Bayer y Raffo. Carlos Vrech has received personal compensation for consulting, serving on a scientific advisory board, speaking, professional travel/accommodation stipends or other activities from Merck, Novartis, Biogen, Synthon Bago, Gador and Genzyme. Maria Célica Ysrraelit has received personal compensation for consulting, serving on a scientific advisory board, speaking, professional travel/accommodation stipends or other activities from Merck, Biogen, Novartis, Roche and Bayer Argentina. Liliana Patrucco has received speaker honoraria from Biogen, Genzyme, Merck-Serono, Novartis and Roche. Has received travel grants and attended courses and conferences on behalf of Merck-Serono, Genzyme and Roche. All the other authors have nothing to disclose., (Copyright © 2020 Elsevier B.V. All rights reserved.)

The objective of this study was to describe and compare the baseline epidemiological data of multiple sclerosis (MS) and neuromyelitis optica spectrum disorder (NMOSD) patients included in RelevarEM (Clinical Trials registry number NCT03375177)., Methods: RelevarEM is a longitudinal, strictly observational MS and NMOSD registry in Argentina. Epidemiological and comorbidity data from MS and NMOSD patients were described and compared. For comorbidities, the Charlson comorbidity index (CCI) was used to calculate the burden at entry. CCI was stratified in 0 and ≥ 1 and described for the entire cohort., Results: A total of 1588 and 75 MS and NMOSD patients (respectively) were included. For MS patients, the mean age was 42 ± 7 years, female sex 65.3%, mean EDSS 2, and mean disease duration 8 ± 6 years. In NMOSD, the mean age was 40 ± 7 years, female sex 78.7%, mean disease duration 5 ± 3.5 years, and mean EDSS 2.5. The most frequent MS phenotype was RRMS in 82.4%. In MS, the CCI was 0 in 85.8.2% while ≥ 1 was in 14.2% of patients. Regarding phenotype stratification, CCI ≥ 1 was 3.9% in CIS, 13.5% in RRMS, 28.7% in SPMS, and 17.4% in PPMS (p < 0.001 between groups). In NMOSD, the CCI was 0 in 64% while ≥ 1 was in 36%. The MS/NMOSD ratio found was 21/1., Conclusions: This is the first analysis of the longitudinal Argentinean registry of MS and NMOSD describing and comparing conditions that contributes to provide reliable real-world data in the country.

Background: The Treatment Burden Questionnaire (TBQ) is a self-reported measure of the effect of treatment workload on patient wellbeing. We sought to validate the TBQ in Spanish and use it to estimate the burden of treatment in Argentinian patients with multiple sclerosis (MS)., Methods: The TBQ was forward-backward translated into Spanish. Two focus groups and 25 semi-structured interviews focused on wording and possible item exclusion. Validation was performed in 2 steps. First, 162 patients across a range of MS severity completed the questionnaire. Confirmatory factor analysis assessed the dimensional structure of the TBQ. Construct validity was assessed by studying correlations with fatigue and quality of life (QoL). Then, in a second cohort of 171 patients, we evaluated the association between TBQ scores and patients' sex, age, education level, employment status, type of MS, disease duration, comorbidities, EDSS, pharmacological treatment and medication adherence., Results: The questionnaire presented a 3-factor structure in which burden was related to pharmacological treatment; comprehensive health assistance; and psycho-social-economic context. Composite reliability was > 0.8 for all factors. TBQ showed positive correlation with fatigue (r s  = 0.467, p = 0.006), negative correlation with QoL (r s  - 0.446, p = 0.009). For the second cohort, total TBQ score was 43 (SD 29). Lowest scores were observed on self-monitoring (0.53, SD 1.3) and highest for administrative load (4.2, SD 3.4). Inverse association was found between the TBQ score and medication adherence (r 0.243 p = 0.001). TBQ scores also correlated with daily patient pill/injection requirements (r 0.175 p = 0.020). Individuals receiving injectable treatment scored higher than patients on oral drugs (total TBQ 51 (SD 32) vs 39 (SD 27) p = 0.002)., Conclusions: The TBQ in Spanish is a reliable instrument and showed adequate correlation with QoL and adherence scales in MS patients. TBQ may benefit health resources allocation and provide tailor therapeutic interventions to construct a minimally disruptive care.

Despite that different registries already exist in various countries in Europe and North America, no ongoing nationwide registry exists in Latin America (LATAM), a region where the disease behaves differently than in other regions. The objective of this document is to describe the methodology behind RelevarEM, the first nationwide MS registry in Argentina and LATAM. METHODS: In this article, we described the creation, implementation and data management of the nationwide MS registry in Argentina. The registry contains information on the structure, ethical aspects, implementation and variables of the registry (Clinical Trials registry number NCT NCT03375177). CONCLUSION: RelevarEM is the first MS nationwide registry in Argentina, as well as in LATAM, with the objective of providing reliable real-world data of MS in the country., (Copyright © 2019 Elsevier B.V. All rights reserved.)

One of the biggest challenges in multiple sclerosis (MS) is the definition of treatment response/failure in order to optimize treatment decisions in affected patients. The objective of this consensus was to review how disease activity should be assessed and to propose recommendations on the identification of treatment failure in RRMS patients in Argentina., Methods: A panel of experts in neurology from Argentina, dedicated to the diagnosis and care of MS patients, gathered both virtually and in person during 2016 and 2017 to carry out a consensus recommendation on the identification of treatment failure in RRMS patients. To achieve consensus, the methodology of "formal consensus-RAND/UCLA method" was used., Results: Recommendations were established based on published evidence and the expert opinion. Recommendations focused on disease management, disease activity markers and treatment failure identification were determined. Main consensus were: ≥2 relapses during the first year of treatment and/or ≥3 new or enlarged T2 or T1 GAD+ lesions and/or sustained increase of ≥2 points in EDSS or ≥100% in T25FW defines treatment failure in RRMS patients., Conclusions: The recommendations of this consensus guidelines attempts to optimize the health care and management of patients with MS in Argentina., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Background: In recent years, neurologists are noticing that evaluation of multiple sclerosis (MS) patients based on combining relapses, disability progression, and magnetic resonance imaging activity may be insufficient to adequately assess suboptimal responses to available therapy. Inclusion of quality of life (QoL) parameters may contribute to breach this gap., Objective: To evaluate agreement levels between doctor and patient perception of QoL in MS., Methods: A total of 700 MS patients and 300 neurologists were invited to participate in a cross-sectional study by answering an e-mail questionnaire. The survey collected information on demographical data and included the Short Form questionnaire (SF-36). After completing the questionnaire, patients were given a standard written description of each of the subdomains assessed by SF-36 and asked to identify which three were the most important determinants of their overall health-related QoL., Results: A total of 135 neurologists and 380 MS patients responded the survey. Study population mean age was 42.1 ± 10.5 years, with 61% presenting relapsing-remitting MS. SF-36 results were physical function 68.4 ± 30, physical role limitation 56.8 ± 41.7, vitality 47.6 ± 21.4, pain 71.2 ± 26.1, social function 72.6 ± 28.6, emotional role limitation 63.2 ± 39.8, mental health 60 ± 14.1, and general health 55.8 ± 22. Doctors considered physical function (75%) and physical role limitation (70%) as the most important QoL determinants in MS, followed by emotional role limitation (52%). Patients however, assigned significantly different levels of importance to physical function (58%), and physical role limitation (46%) and considered vitality (52%) more important than their physicians ( p  < 0.001). Important to note, the results of SF-36 questionnaire were highly correlated with the perception gap between patients and neurologists ( r  = 0.89; p  = 0.0004)., Conclusion: Concerns on QoL in MS are different for patients and physicians. It is essential to enhance communication in order to better understand actual patient needs.

Background: Characteristics at clinically isolated syndrome (CIS) examination assist in identification of patient at highest risk of early second attack and could benefit the most from early disease-modifying drugs (DMDs)., Objective: To examine determinants of second attack and validate a prognostic nomogram for individualised risk assessment of clinical conversion., Methods: Patients with CIS were prospectively followed up in the MSBase Incident Study. Predictors of clinical conversion were analysed using Cox proportional hazards regression. Prognostic nomograms were derived to calculate conversion probability and validated using concordance indices., Results: A total of 3296 patients from 50 clinics in 22 countries were followed up for a median (inter-quartile range (IQR)) of 1.92 years (0.90, 3.71). In all, 1953 (59.3%) patients recorded a second attack. Higher Expanded Disability Status Scale (EDSS) at baseline, first symptom location, oligoclonal bands and various brain and spinal magnetic resonance imaging (MRI) metrics were all predictors of conversion. Conversely, older age and DMD exposure post-CIS were associated with reduced rates. Prognostic nomograms demonstrated high concordance between estimated and observed conversion probabilities., Conclusion: This multinational study shows that age at CIS onset, DMD exposure, EDSS, multiple brain and spinal MRI criteria and oligoclonal bands are associated with shorter time to relapse. Nomogram assessment may be useful in clinical practice for estimating future clinical conversion.

Introduction: Susac Syndrome is an autoimmune endotheliopathy affecting capillaries and precapillary arterioles of the brain, inner ear and retina. The classic symptom triad includes visual disturbances, hypoacusia, and encephalopathy, but is rarely fully manifest at onset. The syndrome typically follows an active fluctuating monophasic course. Typical imaging findings on brain magnetic resonance show central fiber microischemias/microinfarctions of the corpus callosum known as "snow balls", as well as lineal infarcts and upper callosal fiber involvement. Fluorescein angiography and tonal audiometry are important tools to confirm diagnosis, even in patients who are asymptomatic for visual or auditory disturbances. We describe 8 patients with Susac Syndrome treated at our center and compare findings to those of other published case series., Methods: Eight adults with Susac Syndrome diagnosed between January 2007 and August 2016 at our center, in Buenos Aires, Argentina are described. Magnetic Brain Resonance, fluorescein angiography, tonal audiometry, a complete serologic battery and lumbar puncture were performed to all patients., Results: The majority of patients were males, and average age at diagnosis was 37.5 years (range: 22-52 yrs). Two patients presented full clinical triad at onset, while the remaining developed visual and/or auditory disturbances later during the course of disease. All cases manifested varied neurological symptoms including pyramidal and/or sensory tract symptoms, amnesic disorders, ataxia and vertigo. Psychiatric manifestations such as disinhibition, aggressive behavior, paranoid ideation and hallucinations were also present. Seven patients suffered at least one relapse. Typical central corpus callosum fiber ischemias/infarcts, also known as snowball lesions were visible in all patients. Spokes, icicles, periventricular lesions and internal capsule "string of beads" patterns were observed on diffusion weighted images. Four cases presented fornix microischemias/microinfarctions, 5 juxtacortical involvement and 3 infratentorial infarcts. Leptomeningeal involvement was evident in only 1 patient after rabies vaccination. Fluorescein angiography was abnormal in 7 cases. Tonal audiometry revealed unilateral hypoacusia in 5 patients, 3 with low frequency hearing loss. Immunosuppressive treatment was indicated in all cases. Patient follow up ranged between 6 months and 9 years, only 1 patient was lost to follow up after three years., Conclusion: Susac Syndrome is probably both underdiagnosed and misdiagnosed. Early and aggressive immunosuppressive treatment is indicated in order to prevent potential disabilities., (Copyright © 2017 Elsevier B.V. All rights reserved.)

During the past decades, better understanding of relapsing-remitting multiple sclerosis disease mechanisms have led to the development of several disease-modifying therapies, reducing relapse rates and severity, through immune system modulation or suppression. In contrast, current therapeutic options for progressive multiple sclerosis remain comparatively disappointing and challenging. One possible explanation is a lack of understanding of pathogenic mechanisms driving progressive multiple sclerosis. Furthermore, diagnosis is usually retrospective, based on history of gradual neurological worsening with or without occasional relapses, minor remissions or plateaus. In addition, imaging methods as well as biomarkers are not well established. Magnetic resonance imaging studies in progressive multiple sclerosis show decreased blood-brain barrier permeability, probably reflecting compartmentalization of inflammation behind a relatively intact blood-brain barrier. Interestingly, a spectrum of inflammatory cell types infiltrates the leptomeninges during subpial cortical demyelination. Indeed, recent magnetic resonance imaging studies show leptomeningeal contrast enhancement in subjects with progressive multiple sclerosis, possibly representing an in vivo marker of inflammation associated to subpial demyelination. Treatments for progressive disease depend on underlying mechanisms causing central nervous system damage. Immunity sheltered behind an intact blood-brain barrier, energy failure, and membrane channel dysfunction may be key processes in progressive disease. Interfering with these mechanisms may provide neuroprotection and prevent disability progression, while potentially restoring activity and conduction along damaged axons by repairing myelin. Although most previous clinical trials in progressive multiple sclerosis have yielded disappointing results, important lessons have been learnt, improving the design of novel ones. This review discusses mechanisms involved in progressive multiple sclerosis, correlations between histopathology and magnetic resonance imaging studies, along with possible new therapeutic approaches., (© The Author (2016). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Background: Age at onset (AAO) in multiple sclerosis (MS) is an important marker of disease severity and may have prognostic significance. Understanding what factors can influence AAO may shed light on the aetiology of this complex disease, and have applications in the diagnostic process., Methods: The study cohort of 22 162 eligible patients from 21 countries was extracted from the MSBase registry. Only patients with MS aged ≥16 years were included. To reduce heterogeneity, only centres of largely European descent were included for analysis. AAO was defined as the year of the first symptom suggestive of inflammatory central nervous system demyelination. Predictors of AAO were evaluated by linear regression., Results: Compared with those living in lower latitudes (19.0-39.9°), onset of symptoms was 1.9 years earlier for those at higher latitudes (50.0-56.0°) (p=3.83×10 -23 ). A reciprocal relationship was seen for ambient ultraviolet radiation (UVR), with a significantly increasing AAO for patients with MS per each quartile increment of ambient UVR (p=1.56×10 -17 ). We found that the AAO of female patients was ∼5 months earlier than male patients (p=0.002). AAO of progressive-onset patients with MS were ∼9 years later than relapsing-onset patients (p=1.40×10 -265 )., Conclusions: An earlier AAO in higher latitude regions was found in this worldwide European-descent cohort and correlated inversely with variation in latitudinal UVR. These results suggest that environmental factors which act at the population level may significantly influence disease severity characteristics in genetically susceptible populations., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.)

Objective: We aimed to analyse the effect of the introduction of fingolimod, the first oral disease-modifying therapy, on treatment utilisation and persistence in an international cohort of patients with multiple sclerosis (MS)., Methods: MSBASIS, a prospective, observational sub-study of the MSBase registry, collects demographic, clinical and paraclinical data on patients followed from MS onset (n=4718). We conducted a multivariable conditional risk set survival analysis to identify predictors of treatment discontinuation, and to assess if the introduction of fingolimod has altered treatment persistence., Results: A total of 2640 patients commenced immunomodulatory therapy. Following the introduction of fingolimod, patients were more likely to discontinue all other treatments (hazard ratio 1.64, p<0.001) while more patients switched to fingolimod than any other therapy (42.3% of switches). Patients switched to fingolimod due to convenience. Patients treated with fingolimod were less likely to discontinue treatment compared with other therapies (p<0.001). Female sex, country of residence, younger age, a high Expanded Disability Status Scale score and relapse activity were all independently associated with higher rates of treatment discontinuation., Conclusion: Following the availability of fingolimod, patients were more likely to discontinue injectable treatments. Those who switched to fingolimod were more likely to do so for convenience. Persistence was improved on fingolimod compared to other medications., (© The Author(s), 2015.)

Prevention of irreversible disability is currently the most important goal of disease modifying therapy for multiple sclerosis. The disability outcomes used in most clinical trials rely on progression of Expanded Disability Status Scale score confirmed over 3 or 6 months. However, sensitivity and stability of this metric has not been extensively evaluated. Using the global MSBase cohort study, we evaluated 48 criteria of disability progression, testing three definitions of baseline disability, two definitions of progression magnitude, two definitions of long-term irreversibility and four definitions of event confirmation period. The study outcomes comprised the rates of detected progression events per 10 years and the proportions of the recorded events persistent at later time points. To evaluate the ratio of progression frequency and stability for each criterion, we calculated the proportion of events persistent over the five subsequent years once progression was achieved. Finally, we evaluated the clinical and demographic determinants characterising progression events and, for those that regressed back to baseline, determinants of their subsequent regression. The study population consisted of 16 636 patients with the minimum of three recorded disability scores, totalling 112 584 patient-years. The progression rates varied between 0.41 and 1.14 events per 10 years, with the length of required confirmation interval as the most important determinant of the observed variance. The concordance among all tested progression criteria was only 17.3%. Regression of disability occurred in 11-34% of the progression events over the five subsequent years. The most important determinant of progression stability was the length of the confirmation period. For the most accurate set of the progression criteria, the proportions of 3-, 6-, 12- or 24-month confirmed events persistent over 5 years reached 70%, 74%, 80% and 89%, respectively. Regression post progression was more common in younger patients, relapsing-remitting disease course, and after a smaller change in disability, and was inflated by higher visit frequency. These results suggest that the disability outcomes based on 3-6-month confirmed disability progression overestimate the accumulation of permanent disability by up to 30%. This could lead to spurious results in short-term clinical trials, and the issue may be magnified further in cohorts consisting predominantly of younger patients and patients with relapsing-remitting disease. Extension of the required confirmation period increases the persistence of progression events., (© The Author (2015). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Limited data suggest that multiple sclerosis (MS) in Latin America (LA) could be less severe than in the rest of the world. The objective was to compare the course of MS between LA and other regions., Methods: Centers from 18 countries with >20 cases enrolled in the MSBase Registry participated. Patients with MS with a disease duration of >1 year and <30 years at time of EDSS measurement were evaluated. The MS Severity Score (MSSS) was used as a measure of disease progression. Comparisons among regions (North America, Europe, Australia and LA), hemispheres and countries were performed., Results: A total of 9610 patients were included. Patients were from: Europe, 6290 (65.6%); North America, 1609 (16.7%); Australia, 1119 (11.6%); and LA, 592 (6.1%). The mean MSSS in patients from LA was 4.47 ± 2.8, 4.53 ± 2.8 in North America, 4.51 ± 2.8 in Europe and 4.49 ± 2.7 in Australia. Mean MSSS in the northern hemisphere was 4.51 ± 1.6 compared to 4.48 ± 1.9 in the southern hemisphere. No differences were found for MSSS among hemispheres ( p  = 0.68), regions ( p  = 0.96) or countries ( p  = 0.50)., Conclusions: Our analyses did not discover any difference in mean MSSS among patients from different regions, hemispheres or countries.

Background: Multiple Sclerosis is more common in women than men and females have more relapses than men. In a large international cohort we have evaluated the effect of gender on disability accumulation and disease progression to determine if male MS patients have a worse clinical outcome than females., Methods: Using the MSBase Registry, data from 15,826 MS patients from 25 countries was analysed. Changes in the severity of MS (EDSS) were compared between sexes using a repeated measures analysis in generalised linear mixed models. Kaplan-Meier analysis was used to test for sex difference in the time to reach EDSS milestones 3 and 6 and the secondary progressive MS., Results: In relapse onset MS patients (n = 14,453), males progressed significantly faster in their EDSS than females (0.133 vs 0.112 per year, P<0.001,). Females had a reduced risk of secondary progressive MS (HR (95% CI) = 0.77 (0.67 to 0.90) P = 0.001). In primary progressive MS (n = 1,373), there was a significant increase in EDSS over time in males and females (P<0.001) but there was no significant sex effect on the annualized rate of EDSS change., Conclusion: Among registrants of MSBase, male relapse-onset patients accumulate disability faster than female patients. In contrast, the rate of disability accumulation between male and female patients with primary progressive MS is similar.

Objective: To assess demographic, clinical, magnetic resonance imaging, and treatment exposure predictors of time to 3 or 12-month confirmed disability worsening in clinically isolated syndrome (CIS) and early multiple sclerosis (MS)., Methods: We utilized the MSBase Incident Study (MSBasis), a prospective cohort study of outcome after CIS. Predictors of time to first 3 and 12-month confirmed expanded disability status scale worsening were analyzed using Cox proportional hazards regression., Results: About 1989 patients were analyzed, the largest seen-from-onset cohort reported to-date. A total of 391 patients had a first 3-month confirmed disability worsening event, of which 307 were sustained for 12 months. Older age at CIS onset (adjusted hazard ratio: aHR 1.17, 95% 1.06, 1.30), pyramidal (aHR 1.45, 95% CI 1.13, 1.89) and ambulation (HR 1.60, 95% CI 1.09, 2.34) system dysfunction, annualized relapse rate (aHR 1.20, 95% CI 1.18, 1.22), and lower proportion of observation time on treatment were associated with 3-month confirmed worsening. Predictors of time to 12-month sustained worsening included pyramidal system dysfunction (Hazard ratio: aHR 1.38, 95% CI 1.05, 1.83), and older age at CIS onset (aHR 1.17, 95% CI 1.04, 1.31). Greater proportion of follow-up time exposed to treatment was associated with greater reductions in the rate of worsening., Interpretation: This study provides class IV evidence for a strong protective effect of disease-modifying treatment to reduce disability worsening events in patients with CIS and early MS, and confirms age and pyramidal dysfunction at onset as risk factors.

Background: Recently, salt has been shown to modulate the differentiation of human and mouse Th17 cells and mice that were fed a high-sodium diet were described to develop more aggressive courses of experimental autoimmune encephalomyelitis. However, the role of sodium intake in multiple sclerosis (MS) has not been addressed. We aimed to investigate the relationship between salt consumption and clinical and radiological disease activity in MS., Methods: We conducted an observational study in which sodium intake was estimated from sodium excretion in urine samples from a cohort of 70 relapsing-remitting patients with MS who were followed for 2 years. The effect of sodium intake in MS disease activity was estimated using regression analysis. We then replicated our findings in a separate group of 52 patients with MS., Results: We found a positive correlation between exacerbation rates and sodium intake in a multivariate model adjusted for age, gender, disease duration, smoking status, vitamin D levels, body mass index and treatment. We found an exacerbation rate that was 2.75-fold (95% CI 1.3 to 5.8) or 3.95-fold (95% CI 1.4 to 11.2) higher in patients with medium or high sodium intakes compared with the low-intake group. Additionally, individuals with high-sodium intake had a 3.4-fold greater chance of developing a new lesion on the MRI and on average had eight more T2 lesions on MRI. A similar relationship was found in the independent replication group., Conclusions: Our results suggest that a higher sodium intake is associated with increased clinical and radiological disease activity in patients with MS., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.)

Objectives: The aim was to analyse risk of relapse phenotype recurrence in multiple sclerosis and to characterise the effect of demographic and clinical features on this phenotype., Methods: Information about relapses was collected using MSBase, an international observational registry. Associations between relapse phenotypes and history of similar relapses or patient characteristics were tested with multivariable logistic regression models. Tendency of relapse phenotypes to recur sequentially was assessed with principal component analysis., Results: Among 14,969 eligible patients (89,949 patient-years), 49,279 phenotypically characterised relapses were recorded. Visual and brainstem relapses occurred more frequently in early disease and in younger patients. Sensory relapses were more frequent in early or non-progressive disease. Pyramidal, sphincter and cerebellar relapses were more common in older patients and in progressive disease. Women presented more often with sensory or visual symptoms. Men were more prone to pyramidal, brainstem and cerebellar relapses. Importantly, relapse phenotype was predicted by the phenotypes of previous relapses. (OR = 1.8-5, p = 10(-14)). Sensory, visual and brainstem relapses showed better recovery than other relapse phenotypes. Relapse severity increased and the ability to recover decreased with age or more advanced disease., Conclusion: Relapse phenotype was associated with demographic and clinical characteristics, with phenotypic recurrence significantly more common than expected by chance., (© The Author(s), 2014.)

The aim of this work was to evaluate sex differences in the incidence of multiple sclerosis relapses; assess the relationship between sex and primary progressive disease course; and compare effects of age and disease duration on relapse incidence. Annualized relapse rates were calculated using the MSBase registry. Patients with incomplete data or <1 year of follow-up were excluded. Patients with primary progressive multiple sclerosis were only included in the sex ratio analysis. Relapse incidences over 40 years of multiple sclerosis or 70 years of age were compared between females and males with Andersen-Gill and Tweedie models. Female-to-male ratios stratified by annual relapse count were evaluated across disease duration and patient age and compared between relapse-onset and primary progressive multiple sclerosis. The study cohort consisted of 11 570 eligible patients with relapse-onset and 881 patients with primary progressive multiple sclerosis. Among the relapse-onset patients (82 552 patient-years), 48,362 relapses were recorded. Relapse frequency was 17.7% higher in females compared with males. Within the initial 5 years, the female-to-male ratio increased from 2.3:1 to 3.3:1 in patients with 0 versus ≥4 relapses per year, respectively. The magnitude of this sex effect increased at longer disease duration and older age (P < 10(-12)). However, the female-to-male ratio in patients with relapse-onset multiple sclerosis and zero relapses in any given year was double that of the patients with primary progressive multiple sclerosis. Patient age was a more important determinant of decline in relapse incidence than disease duration (P < 10(-12)). Females are predisposed to higher relapse activity than males. However, this difference does not explain the markedly lower female-to-male sex ratio in primary progressive multiple sclerosis. Decline in relapse activity over time is more closely related to patient age than disease duration.

Susac's syndrome is a treatable microangiopathy of unknown etiology affecting arterioles of the brain, retina, and cochlea. The typical clinical manifestation is the triad of encephalopathy, visual loss, and sensorineural hearing loss. One or more of these features may not be present at onset and therefore Susac's syndrome's diagnosis may be difficult. We describe the clinical presentation, diagnostic tests, and treatment of three cases diagnosed and treated at our institution., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Objectives: To compare treatment persistence between two dosages of interferon β-1a in a large observational multiple sclerosis registry and assess disease outcomes of first line MS treatment at these dosages using propensity scoring to adjust for baseline imbalance in disease characteristics., Methods: Treatment discontinuations were evaluated in all patients within the MSBase registry who commenced interferon β-1a SC thrice weekly (n = 4678). Furthermore, we assessed 2-year clinical outcomes in 1220 patients treated with interferon β-1a in either dosage (22 µg or 44 µg) as their first disease modifying agent, matched on propensity score calculated from pre-treatment demographic and clinical variables. A subgroup analysis was performed on 456 matched patients who also had baseline MRI variables recorded., Results: Overall, 4054 treatment discontinuations were recorded in 3059 patients. The patients receiving the lower interferon dosage were more likely to discontinue treatment than those with the higher dosage (25% vs. 20% annual probability of discontinuation, respectively). This was seen in discontinuations with reasons recorded as "lack of efficacy" (3.3% vs. 1.7%), "scheduled stop" (2.2% vs. 1.3%) or without the reason recorded (16.7% vs. 13.3% annual discontinuation rate, 22 µg vs. 44 µg dosage, respectively). Propensity score was determined by treating centre and disability (score without MRI parameters) or centre, sex and number of contrast-enhancing lesions (score including MRI parameters). No differences in clinical outcomes at two years (relapse rate, time relapse-free and disability) were observed between the matched patients treated with either of the interferon dosages., Conclusions: Treatment discontinuations were more common in interferon β-1a 22 µg SC thrice weekly. However, 2-year clinical outcomes did not differ between patients receiving the different dosages, thus replicating in a registry dataset derived from "real-world" database the results of the pivotal randomised trial. Propensity score matching effectively minimised baseline covariate imbalance between two directly compared sub-populations from a large observational registry.

Although the definition of benign multiple sclerosis (BMS) remains controversial, it is generally applied to a subgroup of MS patients showing little disease progression, with minimal disability decades after disease onset, and is based mainly on changes in motor function. Recent studies, however, reveal that deterioration of cognitive function, fatigue, pain, and depression also occur in BMS patients, causing negative impact on work and social activities, despite complete preservation of motor function. Using conventional MRI techniques, lesion load observed in BMS is similar to levels in other disease subtypes; however, newer quantitative MRI techniques show less tissue damage, as well as greater repair and compensatory efficiency following MS injury. Currently accepted criteria for BMS diagnosis may cause overestimation of true prevalence, underscoring the need for routine monitoring of nonmotor symptoms and imaging studies. Clearly, the definition of BMS currently applied in clinical practice requires reassessment.

Objective: To analyze time-trends in age at disability milestones among MS patients who were enrolled into the MSBase International Registry during 1996-2010 period., Methods: We used linear regression to describe the relationship between mean age at major EDSS benchmarks and calendar time. We then assessed time-trend in age at initial EDSS rating with a three level linear growth model specifying that patients were nested within each of 20 participating countries. The model estimated the average of time-trends in mean age at initial clinical assessment within each country while controlling for patients' EDSS and sex in each country. Analyses were repeated in subsamples of patients diagnosed according to Poser or McDonald criteria., Results: The MSBase Registry contained data on 11,108 MS patients enrolled between 1996 and 2010 who fulfilled our inclusion criteria. During the 1996-2010 period, enrollment age for patients with EDSS 4/4.5 increased by 7.9 years, from 43 to 51 years (p<0.001), and for EDSS 6/6.5 - by 4.9 years, from 48 to 53 year (p<0.001). These trends were consistent across 20 investigator countries and were observed in Poser-diagnosed as well as McDonald-diagnosed patient subsets., Conclusions: The more recent MSBase enrollees in each of the mild-to-moderate disability strata were significantly older than earlier enrollees. Possible explanations for this phenomenon are discussed., (Copyright © 2012 Elsevier B.V. All rights reserved.)

The objective of this study is to assess attention in recently diagnosed relapsing-remitting multiple sclerosis patients. Twenty-seven patients with early multiple sclerosis and low clinical disability scores (EDSS<2) and 27 sex-, age-, and education-matched healthy controls underwent attention assessment using the Attentional Network Test, a computerized task designed to measure efficiency independently in 3 attentional networks (Alerting, Orienting and Executive Control). MS patients had significantly less efficiency in the Alerting network (p = .006). In contrast, in the Orienting and Executive Control networks, they did not differ from controls. A significant interaction between Alerting and Executive Control was also found in the MS patients (p = .007). Early relapsing-remitting multiple sclerosis particularly affects the Alerting domain of attention, whereas the Orienting and Executive Control domains are not affected.

Background: The Expanded Disability Status Scale (EDSS) is widely used to rate multiple sclerosis (MS) disability, but lack of disease duration information limits utility in assessing severity. EDSS ranking at specific disease durations was used to devise the MS Severity Score, which is gaining popularity for predicting outcomes. As this requires validation in longitudinal cohorts, we aimed to assess the utility of EDSS ranking as a predictor of 5-year outcome in the MSBase Registry., Methods: Rank stability of EDSS over time was examined in the MSBase Registry, a large multicentre MS cohort. Scores were ranked for 5-year intervals, and correlation of rank across intervals was assessed using Spearman's rank correlation. EDSS progression outcomes at 10 years were disaggregated by 5-year EDSS scores., Results: Correlation coefficients for EDSS rank over 5-year intervals increased with MS duration: years 1-6=0.55, years 4-9=0.74, years 7-12=0.80 and years 10-15=0.83. EDSS progression risk at 10 years after onset was highly dependent on EDSS at 5 years; one-point progression risk was greater for EDSS score of >2 than ≤2. Two-point progression was uncommon for EDSS score of <2 and more common at EDSS score of 4., Conclusions: EDSS rank stability increases with disease duration, probably due to reduced relapses and less random variation in later disease. After 4 years duration, EDSS rank was highly predictive of EDSS rank 5 years later. Risk of progression by 10 years was highly dependent on EDSS score at 5 years duration. We confirm the utility of EDSS ranking to predict 5-year outcome in individuals 4 years after disease onset.

Objectives: We conducted a prospective study, MSBASIS, to assess factors leading to first treatment discontinuation in patients with a clinically isolated syndrome (CIS) and early relapsing-remitting multiple sclerosis (RRMS)., Methods: The MSBASIS Study, conducted by MSBase Study Group members, enrols patients seen from CIS onset, reporting baseline demographics, cerebral magnetic resonance imaging (MRI) features and Expanded Disability Status Scale (EDSS) scores. Follow-up visits report relapses, EDSS scores, and the start and end dates of MS-specific therapies. We performed a multivariable survival analysis to determine factors within this dataset that predict first treatment discontinuation., Results: A total of 2314 CIS patients from 44 centres were followed for a median of 2.7 years, during which time 1247 commenced immunomodulatory drug (IMD) treatment. Ninety percent initiated IMD after a diagnosis of MS was confirmed, and 10% while still in CIS status. Over 40% of these patients stopped their first IMD during the observation period. Females were more likely to cease medication than males (HR 1.36, p = 0.003). Patients treated in Australia were twice as likely to cease their first IMD than patients treated in Spain (HR 1.98, p = 0.001). Increasing EDSS was associated with higher rate of IMD cessation (HR 1.21 per EDSS unit, p<0.001), and intramuscular interferon-β-1a (HR 1.38, p = 0.028) and subcutaneous interferon-β-1a (HR 1.45, p = 0.012) had higher rates of discontinuation than glatiramer acetate, although this varied widely in different countries. Onset cerebral MRI features, age, time to treatment initiation or relapse on treatment were not associated with IMD cessation., Conclusion: In this multivariable survival analysis, female sex, country of residence, EDSS change and IMD choice independently predicted time to first IMD cessation.

Background: A female/male (F/M) ratio increase over time in multiple sclerosis (MS) patients was demonstrated in many countries around the world. So far, a direct comparison of sex ratio time-trends among MS populations from different geographical areas was not carried out., Objective: In this paper we assessed and compared sex ratio trends, over a 60-year span, in MS populations belonging to different latitudinal areas., Methods: Data of a cohort of 15,996 (F = 11,290; M = 4,706) definite MS with birth years ranging from 1930 to 1989 were extracted from the international MSBase registry and the New Zealand MS database. Gender ratios were calculated by six decades based on year of birth and were adjusted for the F/M born-alive ratio derived from the respective national registries of births., Results: Adjusted sex ratios showed a significant increase from the first to the last decade in the whole MS sample (from 2.35 to 2.73; p = 0.03) and in the subgroups belonging to the areas between 83° N and 45° N (from 1.93 to 4.55; p<0.0001) and between 45° N to 35° N (from 1.46 to 2.30; p<0.05) latitude, while a sex ratio stability over time was found in the subgroup from areas between 12° S and 55° S latitude. The sex ratio increase mainly affected relapsing-remitting (RR) MS., Conclusions: Our results confirm a general sex ratio increase over time in RRMS and also demonstrate a latitudinal gradient of this increase. These findings add useful information for planning case-control studies aimed to explore sex-related factors responsible for MS development.

Background: Recent studies conducted in arthritis, asthma, and inflammatory bowel disease suggest that chitinases are important in inflammatory processes and tissue remodeling., Objective: To investigate the role of chitinases in multiple sclerosis (MS) and neuromyelitis optica (NMO)., Methods: Levels of chitotriosidase, acid mammalian chitinase (AMCase), and chitinase 3-like-1 (CHI3L1) were measured using ELISA, in cerebrospinal fluid (CSF) and in serum from 24 patients with relapsing remitting (RR) MS, 24 patients with secondary progressive (SP) MS, 12 patients with NMO, 24 patients with other inflammatory neurological diseases (OIND), and 24 healthy controls (HCs). The number of anti-MOG cytokine-secreting cells was studied using ELISPOT. Eotaxins, MCP-1, RANTES, and IL-8 were assessed using ELISA. Cell transmigration was determined using an in vitro blood-brain barrier (BBB) model, in the presence and absence of chitinases., Results: CSF chitinase levels were significantly increased in patients with RRMS and NMO compared with HCs and patients with SPMS and OIND. In contrast, no significant differences were detected in serum chitinase levels between groups. Chitinase CSF levels showed correlation with anti-MOG IL-13-producing cells, and eotaxin levels. In vitro experiments showed macrophage chitinase secretion was significantly increased by IL-13, but not by IL-5, IL-6, IL-12, or IFN-γ. Moreover, chitinases enhanced IL-8, RANTES, MCP-1, and eotaxin production, increasing migratory capacity in eosinophils, T cells, and macrophages across an in vitro BBB model., Conclusions: Chitinases increased in the CSF from patients with NMO in response to IL-13. These enhanced levels could contribute to central nervous system inflammation by increasing immune cell migration across the BBB.

Even though the etiology of multiple sclerosis (MS) remains largely unknown, research data support the hypothesis that autoimmunity plays a major role in disease development. Several disease-modifying agents have been approved for the treatment of MS; however, there is still a need for antigen-specific treatments that combine efficacy and safety. DNA vaccination represents a new therapeutic alternative in this respect. Preclinical studies in different models of autoimmunity have demonstrated that injection of plasmid DNA encoding a self-antigen in mice restores self-tolerance, leaving immunity against infectious and tumor antigens intact. Based on this evidence, the first DNA vaccine for MS has been created. Bayhill Therapeutic Inc's BHT-3009 encodes full-length, human myelin basic protein (MBP), and has recently been evaluated in a phase I/II and a phase II clinical trial. BHT-3009 was safe and well tolerated in both trials, inducing immune tolerance that extended beyond MBP to other myelin antigens. In addition, a reduction in the number of active lesions was observed, which was accompanied by a decrease in clinical relapse rates, particularly in patients with high immunological activity at baseline. BHT-3009 appears to be a promising new approach for the treatment of MS, although further clinical trials are warranted to confirm the early findings.

Objectives: To assess the risk of multiple sclerosis (MS) relapses, MRI activity, and T cell responses during systemic infections (SI) in patients with MS., Methods: The authors prospectively studied 60 patients with MS. Twenty patients were evaluated with sequential MRI on initial visit, and 2 and 12 weeks later. Blood samples were collected at first infection symptom and 2, 5, 12, and 24 weeks later, and production of IL-4, IL-10, IL-12, IFN-gamma, TNFalpha, VLA-4, LFA-1, MMP-9, and MMP-2 were measured after infectious antigens (Ag) stimulation., Results: Increased risk of relapse and MRI activity were observed during SI. Numbers of IFN-gamma, TNFalpha, and IL-12 secreting cells, serum concentrations of MMP-9, and expression of VLA-4 and LFA-1 after PBMC viral or bacterial Ag stimulation were higher in samples collected during exacerbations associated to SI. Transwell analysis demonstrated that soluble factors produced during viral stimulation have little effect on myelin specific T cells activity. In contrast, PBMC viral stimulation in the presence of cognate myelin Ag induces maximal effector responses at 20 to 30 times lower than the Ag alone., Conclusions: There was a significant association between systemic infections and risk of MS relapse, increased MRI activity, and T cells activation. Furthermore, infectious agents increased myelin specific T-cells sensitivity to cognate Ag.

Objective: To study immunologic alterations in patients with neuromyelitis optica (NMO)., Methods: The authors studied 8 patients with NMO together with 16 healthy subjects, 16 patients with relapsing remitting multiple sclerosis (RRMS), and 16 patients with secondary progressive MS (SPMS), matched for age and sex, as controls. Because recent histopathologic studies have demonstrated that active NMO lesions consist of perivascular immunoglobulin (Ig) deposition and eosinophil infiltration, IL-5, IL-6, IL-12, IgG, and IgM production by anti-myelin oligodendrocyte glycoprotein (MOG) mononuclear cells in peripheral blood and CSF were selected for study using ELISPOT. Eotaxin-2 (Eo-2) and eotaxin-3 (Eo-3) levels were also assessed using ELISA and eosinophil cationic protein (ECP) levels by radioimmunoassay., Results: MOG-specific responses in CSF showed significant increase in IL-5, IL-6, IgG, and IgM secreting cells in NMO patients compared with patients with RRMS, SPMS and healthy subjects. Interestingly, numbers of IgM secreting cells were significantly higher than identical specificity IgG secreting ones. Moreover, CSF Eo-2, Eo-3, and ECP levels were also significantly higher in NMO patients compared to all three control populations. Anti-MOG IL-12 secreting cells were increased in CSF and peripheral blood from NMO, RRMS, and SPMS patients when compared to healthy subjects., Conclusions: These observations suggest that neuromyelitis optica is associated with a major humoral immune response (particularly anti-MOG IgM production) and eosinophil activation present exclusively in CSF.