Maeda M, Nakao S, Miyazato H, Setoguchi M, Arima S, Higuchi I, Osame M, Taira A, Nomoto K, Toda H
First Department of Internal Medicine, Faculty of Medicine, Kagoshima University, Japan.
Am Heart J. 1995 Apr;129(4):702-7. doi: 10.1016/0002-8703(95)90319-4.
Duchenne and Becker muscular dystrophy (DMD/BMD) are allelic variants caused by mutations in gene-encoding dystrophin. Abnormal expression of dystrophin in skeletal muscle has been shown to correlate with severity of disease. However, in BMD the severity of skeletal and cardiac involvement are not well correlated. We studied the immunostaining pattern of cardiac dystrophin in endomyocardial biopsy specimens from 83 patients with heart disease. Immunohistochemical assessment of dystrophin in four patients with BMD and cardiomyopathy showed a variable distributions of myocytes with continuous, discontinuous, or absent membrane immunostaining patterns. These patterns were obviously different from patterns of other heart diseases. We conclude that the discontinuous immunostaining pattern of cardiac dystrophin is characteristic of BMD and that an absent pattern may be associated with more severe cardiac dysfunction. Because genetic analysis cannot determine the correct diagnosis in 35% of DMD/BMD cases, we recommend routine examination of immunostaining patterns of dystrophin in endomyocardial biopsy specimens in patients with cardiomyopathy suspected to be the result of BMD.
杜兴氏和贝克氏肌营养不良症（DMD/BMD）是由编码抗肌萎缩蛋白的基因突变引起的等位基因变体。已表明骨骼肌中抗肌萎缩蛋白的异常表达与疾病严重程度相关。然而，在BMD中，骨骼和心脏受累的严重程度并无很好的相关性。我们研究了83例心脏病患者心内膜活检标本中心脏抗肌萎缩蛋白的免疫染色模式。对4例BMD合并心肌病患者的抗肌萎缩蛋白进行免疫组织化学评估，结果显示肌细胞的分布各不相同，呈现出连续、不连续或无膜免疫染色模式。这些模式明显不同于其他心脏病的模式。我们得出结论，心脏抗肌萎缩蛋白的不连续免疫染色模式是BMD的特征，而无染色模式可能与更严重的心脏功能障碍有关。由于基因分析在35%的DMD/BMD病例中无法确定正确诊断，我们建议对疑似由BMD导致心肌病的患者进行心内膜活检标本中抗肌萎缩蛋白免疫染色模式常规检查。
