RESUMO
Mitochondrial dysfunction is a plausible cause of muscle fibre damage in a number of myopathies including immune-mediated necrotising myopathy. However, histopathological evidence of mitochondrial dysfunction is not often described in immune-mediated necrotising myopathy and, when present, it is often attributed to patient age. The purpose of this study was to describe features of mitochondrial dysfunction on muscle biopsy in anti-3hydroxy-3-methylglutaryl-CoA reductase immune-mediated necrotising myopathy and explore whether these features are age-related. In this observational case control study, a statistically significant increase in the number of muscle fibres with increased lipid content (pâ¯=â¯0.004) and cytochrome c oxidase-negative/succinate dehydrogenase-positive fibres (pâ¯=â¯0.037) in anti-3hydroxy-3-methylglutaryl-coenzyme immune-mediated necrotising myopathy was found compared to age-matched controls. Therefore, histopathological features of mitochondrial dysfunction are more frequent in anti-3hydroxy-3-methylglutaryl-coenzyme immune-mediated necrotising myopathy than aged-matched controls and therefore, may be contributing to the pathogenesis.
Assuntos
Doenças Autoimunes , Inibidores de Hidroximetilglutaril-CoA Redutases , Doenças Musculares , Miosite , Autoanticorpos , Doenças Autoimunes/patologia , Estudos de Casos e Controles , Coenzimas , Humanos , Hidroximetilglutaril-CoA Redutases , Mitocôndrias/patologia , Músculo Esquelético/patologia , Doenças Musculares/patologia , Miosite/patologia , Necrose/patologiaRESUMO
McArdle disease is the most common of the glycogen storage diseases. Onset of symptoms is usually in childhood with muscle pain and restricted exercise capacity. Signs and symptoms are often ignored in children or put down to 'growing pains' and thus diagnosis is often delayed. Misdiagnosis is not uncommon because several other conditions such as muscular dystrophy and muscle channelopathies can manifest with similar symptoms. A simple exercise test performed in the clinic can however help to identify patients by revealing the second wind phenomenon which is pathognomonic of the condition. Here a patient is reported illustrating the value of using a simple 12 minute walk test.
Assuntos
Teste de Esforço/métodos , Doença de Depósito de Glicogênio Tipo V/patologia , Doença de Depósito de Glicogênio Tipo V/fisiopatologia , Biópsia , Erros de Diagnóstico , Frequência Cardíaca/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo , Caminhada/fisiologiaRESUMO
McArdle disease is the most common of the glycogen storage diseases. Onset of symptoms is usually in childhood with muscle pain and restricted exercise capacity. Signs and symptoms are often ignored in children or put down to ‘growing pains’ and thus diagnosis is often delayed. Misdiagnosis is not uncommon because several other conditions such as muscular dystrophy and muscle channelopathies can manifest with similar symptoms. A simple exercise test performed in the clinic can however help to identify patients by revealing the second wind phenomenon which is pathognomonic of the condition. Here a patient is reported illustrating the value of using a simple 12 minute walk test.
A doença de McArdle é o tipo mais frequente das glicogenoses. A apresentação clínica característica na infância inclui mialgia e intolerância aos esforços/exercício físico. Frequentemente, os sinais e sintomas das crianças não são considerados devidamente, sendo muitas vezes interpretados como “dores do crescimento”, retardando o diagnóstico. Erros diagnósticos não são raros uma vez que outras doenças, como distrofia muscular ou canalopatias musculares, podem apresentar sintomas semelhantes. Entretanto, um simples teste de exercício físico realizado no ambulatório/consultório médico pode ajudar a identificar estes pacientes pois evidencia o fenômeno second wind, patognomônico da doença de McArdle. Aqui é descrito um relato de caso de um paciente ilustrando o valor do simples 12 minutes walk test.