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DOI: 10.1590/0004-282X-ANP-2022-S105
Myasthenia gravis in clinical practice
Miastenia gravis na prática clínica
ABSTRACT
Background: Myasthenia gravis is largely a treatable disease, but it can result in significant morbidity and even mortality, which can usually be avoided, or at least mitigated, with timely diagnosis and appropriate treatment of the disease. Objective: This review aims to summarize the main practical aspects of the diagnostic approach, treatment and care of myasthenic patients. Methods: The authors performed a non-systematic critical review summarizing the main practical aspects of myasthenia gravis. Results: Most patients with myasthenia have autoantibodies targeted at acetylcholine receptors or, less commonly, muscle-specific kinase - MuSK. Electrophysiology plays an important role in the diagnosis of neuromuscular junction dysfunction. The central clinical manifestation of myasthenia gravis is fatigable muscle weakness, which can affect eye, bulbar, respiratory, and limb muscles. With rare exceptions, patients have a good response to symptomatic treatment, but corticosteroids and/or immunosuppressants are usually also necessary to obtain good control of the manifestations of the disease. Conclusion: Knowledge of the peculiar aspects of their clinical and electrophysiological presentations is important for the diagnosis. Likewise, specific treatment and response time to each drug are crucial for proper care.
RESUMO
Antecedentes: A miastenia gravis é, em grande parte, uma doença tratável, mas pode resultar em significativa morbidade e até mortalidade, que geralmente pode ser evitada, ou pelo menos atenuada, com diagnóstico oportuno e tratamento adequado da doença. Objetivo: Esta revisão visa resumir os principais aspectos práticos da abordagem diagnóstica, do tratamento e dos cuidados de pacientes miastênicos. Métodos: Os autores realizaram uma revisão crítica não sistemática, resumindo os principais aspectos práticos da miastenia gravis. Resultados: A maioria dos pacientes com miastenia apresenta autoanticorpos direcionados aos receptores de acetilcolina ou, menos comumente, quinase músculo-específica - MuSK. A eletrofisiologia desempenha um papel importante no diagnóstico da disfunção da junção neuromuscular. A manifestação clínica central da miastenia gravis é a fraqueza muscular fatigável, que pode afetar os músculos oculares, bulbares, respiratórios e dos membros. Com raras exceções, os pacientes respondem bem ao tratamento sintomático, mas geralmente também são necessários corticosteroides e/ou imunossupressores para se obter um bom controle das manifestações da doença. Conclusão: O conhecimento dos aspectos peculiares de suas apresentações clínicas e eletrofisiológicas é importante para o diagnóstico. Da mesma forma, o tratamento específico e o tempo de resposta a cada medicamento são cruciais para o cuidado adequado.
Keywords
Myasthenia Gravis - Neuromuscular Junction - Neuromuscular Diseases - Neuromuscular Junction Diseases - Practice GuidelinePalavras-chave:
Miastenia Gravis - Junção Neuromuscular - Doenças Neuromusculares - Doenças da Junção Neuromuscular - Guia de Prática ClínicaAuthors’ contributions:
All authors contributed equally to this manuscript
Publication History
Received: 16 March 2022
Accepted: 29 April 2022
Article published online:
06 February 2023
© 2022. Academia Brasileira de Neurologia. This is an open access article published by Thieme under the terms of the Creative Commons Attribution-NonDerivative-NonCommercial License, permitting copying and reproduction so long as the original work is given appropriate credit. Contents may not be used for commecial purposes, or adapted, remixed, transformed or built upon. (https://creativecommons.org/licenses/by-nc-nd/4.0/)
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