Laing早发性远端肌病:慢肌球蛋白缺失伴肌活检多种异常  

Laing early onset distal myopathy:Slow myosin defect with variable abnormalities on muscle biopsy

作　　者：Lamont P.J. Udd B. Mastaglia F.L. 高宗恩 

机构地区：[1]Neurogenetic Unit, Department of Neurology, Royal Perth Hospital, Perth, WA 6847, Australia Dr.

出　　处：《世界核心医学期刊文摘（神经病学分册）》2006年第6期34-34,共1页Digest of the World Core Medical Journals:Clinical Neurology

摘　　要：Background: Laing early onset distal myopathy (MPD1) is an autosomal dominant myopathy caused by mutations within the slow skeletal muscle fibre myosin heavy chain gene, MYH7. It is allelic with myosin storage myopathy, with the commonest form of familial hypertrophic cardiomyopathy, and with one form of dilated cardiomyopathy. However, the clinical picture of MPD1 is distinct from these three conditions. Objective: To collate and discuss the histological features reported in the muscle biopsies of MPD1 patients and to outline the clinical features. Results: The phenotype of MPD1 was consistent, with initial weakness of great toe/ankle dorsiflexion, and later development of weakness of finger extension and neck flexion. Age of onset was the only variable, being from birth up to the 20s, but progression was always very slow. The pathological features were variable. In this retrospective series, there were no pathognomonic diagnostic features, although atrophic type I fibres were found in half the families. Rimmed vacuoles are consistently seen in all other distal myopathies with the exception of Myoshi distal myopathy. However, they were found in a minority of patients with MPD1, and were not prominent when present. Immunohistochemical staining for slow and f ast myosin showed co-expression of slow and fast myosin in some type I fibres, possibly indicating a switch to type II status. This may be a useful aid to diagnosis. Conclusions: The pathological findings in MPD1 are variable and appear to be affected by factors such as the specific muscle biopsied, the age of the patient at biopsy, and the duration of disease manifestations.Background： Laing early onset distal myopathy （MPD1） is an autosomal dominant myopathy caused by mutations within the slow skeletal muscle fibre myosin heavy chain gene, MYHT. It is allelic with myosin storage myopathy, with the commonest form of familial hypertrophic cardiomyopathy, and with one form of dilated cardiomyopathy. However, the clinical picture of MPD1 is distinct from these three conditions. Objective： To collate and discuss the histological features reported in the muscle biopsies of MPD1 patients and to outline the clinical features. Resuits： The phenotype of MPD1 was consistent, with initial weakness of great toe/ankle dorsiflexion, and later development of weakness of finger extension and neck flexion. Age of onset was the only variable, being from birth up to the 20s, but progression was always very slow. The pathological features were variable. In this retrospective series, there were no pathognomonic diagnostic features, although atrophic type I fibres were found in half the families. Rimmed vacuoles are consistently seen in all other distal myopathies with the exception of Myoshi distal myopathy. However, they were found in a minority of patients with MPD1, and were not prominent when present. Immunohistochemical staining for slow and fast myosin showed co-expression of slow and fast myosin in ＇some type I fibres, possibly indicating a switch to type Ⅱ status. This may be a useful aid to diagnosis. Conclusions： The pathological findings in MPD1 are variable and appear to be affected by factors suctz as the specific muscle biopsied, the age of the patient at biopsy, and the duration of disease manifestations.

关 键 词：肌球蛋白重链基因 远端肌病 肌活检 早发性 家族性肥厚型心肌病 骨骼肌纤维 异常 常染色体显性 扩张型心肌病 免疫组化染色 

分 类 号：R542.2[医药卫生—心血管疾病] R746[医药卫生—内科学]