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INTRODUCTION: Predicting the conversion of clinically isolated syndrome (CIS) to clinically definite multiple sclerosis (CDMS) is critical to personalizing treatment planning and benefits for patients. The aim of this study is to develop an explainable machine learning (ML) model for predicting this conversion based on demographic, clinical, and imaging data. METHOD: The ML model, Extreme Gradient Boosting (XGBoost), was employed on the public dataset of 273 Mexican mestizo CIS patients with 10-year follow-up. The data was divided into a training set for cross-validation and feature selection, and a holdout test set for final testing. Feature importance was determined using the SHapley Additive Explanations library (SHAP). Then, two experiments were conducted to optimize the model's performance by selectively adding variables and selecting the most contributive variables for the final model. RESULTS: Nine variables including age, gender, schooling, motor symptoms, infratentorial and periventricular lesion at imaging, oligoclonal band in cerebrospinal fluid, lesion and symptoms types were significant. The model achieved an accuracy of 83.6 %, AUC of 91.8 %, sensitivity of 83.9 %, and specificity of 83.4 % in cross-validation. In the final testing, the model achieved an accuracy of 78.3 %, AUC of 85.8 %, sensitivity of 75 %, and specificity of 81.1 %. Finally, a web-based demo of the model was created for testing purposes. CONCLUSION: The model, focusing on feature selection and interpretability, effectively stratifies risk for treatment decisions and disability prevention in MS patients. It provides a numerical risk estimate for CDMS conversion, enhancing transparency in clinical decision-making and aiding in patient care.

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Multiple Sclerosis (MS) is an autoimmune demyelinating disease of the central nervous system (CNS) characterized by damage to the myelin sheaths of oligodendrocytes. Currently, there is no specific biomarker to identify the disease; however, a diagnostic criterion has been established based on patient's clinical, laboratory, and imaging characteristics, which assists in identifying this condition. The primary method for diagnosing MS is the McDonald criteria, first described in 2001 and revised in the years 2005, 2012, and 2017. These criteria have been continuously reviewed to enhance specificity and sensitivity in the diagnosis of MS, thereby reducing errors in its differential diagnosis. An important differential diagnosis that shares overlapping features with MS, mainly the progressive forms, are leukodystrophies with demyelination as underlying pathology. Leukodystrophies comprise a rare group of genetically determined disorders that lead to either demyelination or hypomyelination of the central nervous system that can result neuroimaging changes as well as clinical findings similar to those observed in MS. Thus, systematic evaluation encompassing clinical presentation, neuroimaging findings, and laboratory metrics proves indispensable for a differential diagnosis. As such, this study aimed to establish, clearly and objectively, the similarities and differences between MS and the main demyelinating leukodystrophies. The study analyzed the parameters of the McDonald criteria, including clinical, laboratory, and magnetic resonance imaging aspects, as found in patients with leukodystrophies through scoping literature review. The data were compared with the determinations of the revised 2017 McDonald criteria to facilitate the differential diagnosis of these diseases in clinical practice.

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BACKGROUND: Clinically Isolated Syndrome (CIS) is the first clinical episode suggestive of Clinical Definite Multiple Sclerosis (CDMS). There are no reports on possible predictors of conversion to CDMS in Mexican mestizo patients. AIM OF THE STUDY: To investigate immunological markers, clinical and paraclinical findings, and the presence of herpesvirus DNA to predict the transition from CIS to CDMS in Mexican patients. METHODS: A single-center prospective cohort study was conducted with newly diagnosed patients with CIS in Mexico between 2006 and 2010. Clinical information, immunophenotype, serum cytokines, anti-myelin protein immunoglobulins, and herpes viral DNA were determined at the time of diagnosis. RESULTS: 273 patients diagnosed with CIS met the enrolment criteria; after 10 years of follow-up, 46% met the 2010 McDonald criteria for CDMS. Baseline parameters associated with conversion to CDMS were motor symptoms, multifocal syndromes, and alterations of somatosensory evoked potentials. The presence of at least one lesion on magnetic resonance imaging was the main factor associated with an increased risk of conversion to CDMS (RR 15.52, 95% CI 3.96-60.79, p = 0.000). Patients who converted to CDMS showed a significantly lower percentage of circulating regulatory T cells, cytotoxic T cells, and B cells, and the conversion to CDMS was associated with the presence of varicella-zoster virus and herpes simplex virus 1 DNA in cerebrospinal fluid and blood. CONCLUSION: There is scarce evidence in Mexico regarding the demographic and clinical aspects of CIS and CDMS. This study shows several predictors of conversion to CDMS to be considered in Mexican patients with CIS.

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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.

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Introducción: La polineuropatía desmielinizante inflamatoria crónica (CIDP) es una enfermedad desmielinizante e inflamatoria de mediación autoinmune. El tratamiento convencional es basado en la inmunomodulación e inmunosupresión. El uso de células madre es una terapia novedosa en los trastornos autoinmune, siendo incluida como terapia. Objetivo: Determinar la eficacia de la movilización de células madre mediante la aplicación del factor estimulador de colonias granulocíticas (F-ECG) en pacientes con CIDP que han recibido otras líneas de tratamiento. Material y Métodos: Se realizó un estudio aleatorizado, doble ciego sobre una cohorte de 45 pacientes con CIDP, donde se administró el (F-ECG) en 25 pacientes y 20 continuaron con el tratamiento habitual, tratados anteriormente con otras variantes terapéuticas por más de tres años, sin respuesta satisfactoria. Resultados: Predominio de los hombres para 64,4 por ciento, la Diabetes Mellitus tuvo mayor asociación y la medicación más usada fueron los esteroides. Los síntomas y signos clínicos mejoraron significativamente tras el tratamiento. Los valores de la puntuación del TCSS al mes y 3 meses después del tratamiento disminuyeron significativamente; pero este decremento no se mantuvo al final del estudio. La velocidad de conducción y el potencial de acción de los nervios sensoriales y motores mejoraron considerablemente después del tratamiento. Conclusiones: La efectividad de la aplicación del (F-ECG) para la mejoría de los síntomas clínicos y resultados de estudios neurofisiológicos evolutivamente son mayores que otras variantes terapéuticas en los primeros meses, con buena seguridad y tolerabilidad, por lo que se puede incluir en la terapéutica convencional para la CIDP(AU)

Introduction: Chronic inflammatory demyelinating polyneuropathy (CIDP) is an autoimmune demyelinating disease. Conventional treatment is based on immunomodulation and immunosuppression. The use of stem cells is a novel therapy in autoimmune disorders, so it is included as therapy. Objective: To determine the efficacy of mobilization of stem cells by applying granulocyte colony-stimulating factor (G-CSF) in patients with CIDP who have followed other lines of treatment. Material and Methods: A randomized, double-blind study was carried out on a cohort of 45 patients with CIDP. G-CSF was administered to 25 patients and 20 of them continued with the usual treatment. These patients were previously treated with other therapeutic variants for more than three years without satisfactory response. Results: There was a prevalence of men (64.4 percent), Diabetes Mellitus had a greater association, and the most used medications were steroids. Clinical symptoms and signs improved significantly after treatment. TCSS scores significantly decreased at one and three months after treatment, but this decrease was not maintained at the end of the study. The conduction velocity and action potential of sensory and motor nerves improved considerably after treatment. Conclusions: The effectiveness of the use of G-CSF shows an improvement of clinical symptoms. The results of neurophysiological studies have a better course than other therapeutic variants during the first months, with good safety and tolerability, so it can be included in the conventional therapy for the CIDP(AU)

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O grupo de Doenças Desmielinizantes Adquiridas (DDA) acomete o Sistema Nervoso Central (SNC) com base imunopatológica com produção de anticorpos à bainha de mielina. O diagnóstico é baseado em critérios clínico-radiológicos, sendo importante a busca por novas tecnologias para melhores diagnóstico e terapêutica. A avaliação da resposta inflamatória pode ser preditiva do curso evolutivo, sendo pouco explorada em pediatria. A proposta foi avaliar parâmetros clínico-neurológicos e perfis imunológicos nas DDA pediátricas para identificar biomarcadores dos quatro subtipos de DDA: Encefalomielite Disseminada Aguda (ADEM), Esclerose Múltipla Pediátrica (EMP), Síndrome Clínica Isolada (CIS) e Espectro da Neuromielite Óptica (NMOSD). Foi realizado um estudo prospectivo, longitudinal com portadores de DDA com até 18 anos de idade no Ambulatório de Doenças Desmielinizantes do IFF no período de 2012 a 2016. Os pacientes foram submetidos a exame neurológico evolutivo, Ressonância Magnética (RM) e coleta de sangue para pesquisa de citocinas. Foram admitidos 30 pacientes com 12 exclusões e 3 perdas totalizando 15 pacientes avaliados. O diagnóstico mais encontrado foi ADEM seguido de EMP. Os painéis de citocinas foram comparados através de análise estatística e categorizados de acordo com as comparações. Os resultados foram descritos em gráficos Heatmap, Boxplot e árvore de decisões. Foi relatado um caso sobre a evolução do diagnóstico de CIS para EMP. O perfil de citocinas séricas foi realizado por análise de microarranjo líquido (Luminex) totalizando 64 amostras de sangue avaliadas. A coorte apresentou cinco pacientes ADEM, cinco EMP, dois CIS e três NMOSD. No relato de caso da paciente ALAPL, não foi encontrada sincronia temporal entre a alteração do perfil de citocinas, da RM e da avaliação neurológica concluindo que avaliações inflamatória e clínica não anteciparam eventos de desmielinização e evolução para EMP. A correlação entre dosagens de citocinas mostrou um padrão multifuncional, com a participação de moléculas associadas ao perfil inflamatório Th1, Th2, Th17, Treg, e expressão aumentada de quimiocinas e citocinas envolvidas com proliferação de diversos tipos celulares. O padrão inflamatório mais abrangente e polifuncional, com 20 citocinas significativamente mais expressas, foi entre a EMP comparadas à ADEM. Na análise de citocinas entre ADEM e MNOSD houve uma diferença estatisticamente significativa para IL-7, IL-10 e GM-CSF, com uma expressão maior nas amostras de NMOSD. Entre CIS e ADEM, apenas MIP-1b se apresentou com uma diferença estatística nos dois grupos. A IP-10 se mostrou diferencialmente expressa em EMP quando comparada a CIS. Entre EMP e NMOSD, encontramos a eotaxina aumentada em EMP. Foram criadas quatro árvores classificatórias para o diagnóstico de DDA, definindo o perfil mínimo de citocinas capazes de identificar cada tipo de DDA. Concluímos que do ponto de vista diagnóstico as citocinas IL-2, IL-7, IL-13, Basic-FGF, MIP-1b, VEGF, Eotaxina, IP-10 e TNF- seriam capazes de classificar todos os pacientes DDA em seus grupos específicos. Estudos multicêntricos que permitam aumentar o número de pacientes com DDA poderão auxiliar na validação dos achados desse trabalho e definir pontos de cortes mais precisos para cada nível de citocina sérica visando ao diagnóstico diferencial de DDA em pediatria.

The group of Acquired Demyelinating Diseases (DDA) affects the Central Nervous System (CNS) with immunopathological basis with production of antibodies to the myelin sheath. The diagnosis is based on clinical-radiological criteria, being important the search for new technologies for better diagnosis and therapeutics. The evaluation of the inflammatory response can be predictive of the evolutionary course, being little explored in pediatrics. The purpose of this study was to evaluate clinical and neurological parameters and immunological profiles in pediatric ADIs to identify biomarkers of the four ADD subtypes: Acute Disseminated Encephalomyelitis (ADEM), Pediatric Multiple Sclerosis (EMP), Isolated Clinical Syndrome (CIS) and Optical Neuromyelitis Spectrum ). A prospective, longitudinal study was conducted with patients with ADD up to 18 years of age at the IFF Demyelinating Diseases Clinic in the period from 2012 to 2016. The patients were submitted to evolutionary neurological examination, EDSS, Magnetic Resonance (MRI) and collection to detect cytokines. Thirty patients with 12 exclusions and 3 losses totaling 15 patients were admitted. The most common diagnosis was ADEM followed by EMP. The cytokine panels were compared between the DDAs by statistical analysis and categorized according to the comparisons. The results were described in Heatmap, Boxplot and decision tree charts. A case has been reported on the evolution of the diagnosis of CIS to PMS. Serum cytokine profile was performed by liquid microarray analysis (Luminex), totalizing 64 blood samples. The cohort presented five ADEM, five EMP, two CIS and three NMOSD patients. In the case report of the ALAPL patient, no temporal synchrony was found between the alteration of the cytokine profile, MRI and neurological evaluation, concluding that inflammatory profile evaluations and clinical examination did not anticipate events of demyelination and evolution to PMS. The correlation between cytokine dosages and ADI in pediatrics showed a multifunctional pattern with the participation of molecules associated with the inflammatory profile Th1, Th2, Th17, Treg, and increased expression of chemokines and cytokines involved with proliferation of several cell types. The most comprehensive and multifunctional inflammatory pattern, with 20 significantly more expressed cytokines, was seen among PMS compared to ADEM. In the analysis of cytokines between ADEM and MNOSD there was a statistically significant difference for IL-7, IL-10 and GM-CSF, with a greater expression in the samples of patients with NMOSD. Between CIS and ADEM, only MIP-1b presented a statistical difference in the two groups. IP-10 was differentially expressed in EMP when compared to CIS patients. Among patients with EMP and NMOSD, we found increased eotaxin in EMP. Four classification trees were created for the diagnosis of ADI, defining the minimum profile of cytokines capable of identifying each type of ADI. We conclude that IL-2, IL-7, IL-13, Basic-FGF, MIP-1b, VEGF, Eotaxin, IP-10 and TNF-γ could be classified as diagnostic groups. Multicentric studies that allow an increase in the number of patients with ADD can help to validate the findings of this study and define more precise cutoff points for each level of serum cytokine aiming at the differential diagnosis of AD in pediatrics.

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RESUMO Introdução: a esclerose múltipla (EM) é uma Doença desmielinizante de etiologia autoimune, e está entre as principais causas de incapacidade neurológica não traumática nos adultos jovens. Objetivo: identificar os principais diagnósticos, resultados e intervenções de enfermagem e validar uma proposta de plano de cuidados para pacientes com Esclerose Múltipla. Métodos: estudo metodológico, realizado com 16 enfermeiros especialistas e 68 pacientes em uma unidade de Neurologia de um Hospital Escola, seguindo quatro etapas: elaboração dos Diagnósticos de Enfermagem; proposta inicial de resultados e intervenções de enfermagem; elaboração de um plano de cuidados; validação do plano por especialistas. Para a análise da concordância aplicou-se a escala do Coeficiente Kappa. Resultados: identificou-se quatro diagnósticos com frequência acima de 50 porcento, elencou-se quatro resultados de enfermagem e foram propostas 14 intervenções que alcançaram índice de concordância ≥ 0,8 entre os experts. Conclusão: o estudo permitiu identificar os diagnósticos, resultados e intervenções de enfermagem para aplicação na prática clínica, além de validar a proposta do plano de cuidados para pacientes com Esclerose Múltipla(AU)

RESUMEN Introducción: la esclerosis múltiple es una enfermedad desmielinizante de etiología autoinmune, y está entre las principales causas de incapacidad neurológica no traumática en los adultos jóvenes. Objetivo: identificar los principales diagnósticos, resultados e intervenciones de enfermería y validar una propuesta de plan de cuidados para pacientes con esclerosis múltiple. Métodos: estudio metodológico, realizado con 16 enfermeros especialistas y 68 pacientes en una unidad de Neurología de un Hospital Escuela, siguiendo cuatro etapas: elaboración de los Diagnósticos de Enfermería; Propuesta inicial de resultados e intervenciones de enfermería; Elaboración de un plan de cuidados; Validación del plan por expertos. Para el análisis de la concordancia se aplicó la escala del Coeficiente Kappa. Resultados: se identificaron cuatro diagnósticos con frecuencia por encima del 50 por ciento, se enumeraron cuatro resultados de enfermería y se propusieron 14 intervenciones que alcanzaron índice de concordancia ≥ 0,8 entre los expertos. Conclusión: el estudio permitió identificar los diagnósticos, resultados e intervenciones de enfermería para aplicación en la práctica clínica, además de validar la propuesta del plan de cuidados para pacientes con esclerosis múltiple(AU)

ABSTRACT Introduction: Multiple sclerosis (MS) is a demyelinating disease of autoimmune etiology and is one of the main causes of non-traumatic neurological disability in young adults. Objective: to identify the main nursing diagnoses, results and interventions and to validate a proposal for a care plan for patients with multiple sclerosis. Methods: a methodological study, carried out with 16 specialist nurses and 68 patients in a Neurology unit of a School Hospital, following four stages: elaboration of Nursing Diagnoses Initial proposal of results and nursing interventions; Preparation of a care plan; Validation of the plan by specialists. Kappa coefficient scale was used to analyze the agreement. Results: four diagnoses were identified with frequency above 50 percent, four nursing outcomes were listed and 14 interventions were proposed that reached a concordance index ≥ 0.8 among the experts. Conclusion: the study allowed to identify nursing diagnoses, results and interventions for application in clinical practice, in addition to validating the proposal of the care plan for patients with Multiple Sclerosis(AU)

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Desde o primeiro relato de doença desmielinizante associada a tumores cerebrais por Scherer em 1938, inúmeros outros relatos de casos foram publicados fazendo associação desta doença com diferentes tumores primários do sistema nervoso central. Nosso trabalho descreve o caso de uma paciente de 23 anos com duas lesões encefálicas biopsiadas, mostrando inicialmente processo inflamatório desmielinizante que no seguimento desenvolve um oligodendroglioma anaplásico. A partir deste caso, realizamos uma revisão da literatura dessa associação específica, primeiramente publicada por Barnard e Jellinek em 1967, e ressaltamos a importância da diferenciação entre a forma desmielinizante tumefativa de uma neoplasia cerebral verdadeira. (AU)

Since the first report of demyelinating disease associated with brain tumors by Scherer in 1938, several other case reports have been published making association of this disease with different primary tumors of the central nervous system. Our paper describes the case of a 23 year old patient with two brain lesions, biopsied, initially showing a demyelinating inflammatory process that in the follow up develops an anaplastic oligodendroglioma. From this case, we conducted a literature review of this specific association, first published by Barnard and Jellinek in 1967, and emphasize the importance of difference in a tumefactive demyelinating lesions between of true brain neoplasm. (AU)

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CONTEXTO CLÍNICO: La neuromielitis óptica (NMO) o síndrome de Devic, y su espectro de enfermedades relacionadas, son trastornos inflamatorios del sistema nervioso central (SNC), caracterizados por la desmielinización inmunomediada y el daño axonal que afecta predominantemente los nervios ópticos y la médula espinal. Fue incluida como una variante de la esclerosis múltiple (EM), pero en la actualidad se considera una entidad clínica diferente; con características inmunológicas, diagnósticas y de tratamiento únicas.Mientras la patogénesis de la EM es mediada principalmente por células, en la NMO es mediada por anticuerpos. El descubrimiento de los anticuerpos enfermedad-específicos anti-aquaporina-4 (AQP4) ha llevado a una mejor comprensión de este trastorno. La prevalencia es 0,5 a 4 por 100 000 personas con una mediana de edad de aparición de 32 a 41 años. Las características propias de la NMO, incluyen brotes agudos de neuritis óptica o mielitis transversa. En el 90% de los casos tiene un curso recurrente, con secuelas como ceguera y paraplejía dentro de los cinco años del evento inicial. El diagnóstico se realiza mediante imágenes del SNC y determinación de anticuerpos AQP4 en suero o líquido cefalorraquídeo (LCR) durante el episodio agudo. La determinación de dichos anticuerpos muestra una sensibilidad moderada (71% a 91%) y alta especificidad (91%). Sin embargo, existe una tasa considerable de falsos negativos (9 a 29%). Un bajo número de pacientes con NMO y test negativo para anticuerpos AQP4, presentan anticuerpos antiglicoproteína de la mielina de oligodendrocitos (MOG, del inglés myelin oligodendrocyte glycoprotein) tanto en suero como en LCR. Dichos anticuerpos se encuentran también en pacientes pediátricos con esclerosis múltiple y en la encefalomielitis aguda diseminada. Se postula que la determinación de anticuerpos anti-MOG tiene utilidad diagnóstica en pacientes con NMO y otras enfermedades desmielinizantes. TECNOLOGÍA: La glicoproteína de la mielina de los oligodendrocitos es un componente menor de la mielina del sistema nervioso central, que se expresa en la superficie exterior de las vainas de mielina y las membranas plasmáticas de oligodendrocitos y es altamente inmunogénica. La determinación de anticuerpos Inmunoglobulina G anti-MOG se realiza mediante un enzimo inmuno ensayo (ELISA) con muestra de suero, plasma o LCR. OBJETIVO: Evaluar la evidencia disponible acerca de la eficacia, seguridad y aspectos relacionados a las políticas de cobertura de la determinación de anticuerpos antiglicoproteína de la mielina de oligodendrocitos para el diagnóstico de neuromielitis óptica y otras enfermedades desmielinizantes. MÉTODOS: Se realizó una búsqueda en las principales bases de datos bibliográficas (incluyendo Medline, Cochrane y CRD), en buscadores genéricos de Internet, agencias de evaluación de tecnologías sanitarias y financiadores de salud utilizando la siguiente estrategia: (Anti MOG[tiab] OR Anti Myelin-Oligodendrocyt*[tiab]) AND (Neuromyelitis Optica[Mesh] OR Neuromyelitis Optica[tiab] OR NMO*[tiab] OR Devic[tiab] OR Multiple Sclerosis[Mesh] OR Multiple Sclerosis[tiab] OR Disseminated Sclerosis[tiab]). Se priorizó la inclusión de revisiones sistemáticas (RS), ensayos clínicos controlados aleatorizados (ECAs), evaluaciones de tecnologías sanitarias y económicas, guías de práctica clínica y políticas de cobertura de otros sistemas de salud cuando estaban disponibles. RESULTADOS: No se encontraron estudios que demostraran la precisión de este test para establecer un diagnóstico diferencial entre la NMO y otras enfermedades desmielinizantes. Ante la falta de evidencia, se incluyeron estudios acerca de la prevalencia de este anticuerpo y las características clínicas de los pacientes que lo presentan; incluyéndose, cinco estudios observacionales, dos guías de práctica clínica, un consenso y una política de cobertura. CONCLUSIONES: La evidencia acerca de la utilidad del test de anticuerpos antiglicoproteína de la mielina de oligodendrocitos para el diagnóstico de neuromielitis óptica es de baja calidad. No se encontraron estudios que evaluaran la precisión de este test para diferenciar esta patología de la esclerosis múltiple u otras enfermedades desmielinizantes. Su uso se plantea cuando el diagnóstico no pueda ser realizado con el dosaje de anticuerpos específicos anti-aquaporina-4; pero aún en estos casos, no hay evidencia suficiente que asegure su utilidad. Asimismo, no existe evidencia suficiente que avale su rol en pronóstico clínico de estas patologías. Las guías de práctica clínica relevadas no contemplan su uso o la consideran de utilidad incierta. Los agentes financiadores de salud relevados consideran esta tecnología como experimental.

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