肌营养不良蛋白表达在萎缩性肌病鉴别诊断中的意义

目的探讨肌营养不良蛋白(Dystrophin蛋白)在萎缩性肌病中的表达及其临床意义。方法对均表现为双下肢近端肌肉萎缩的43例肌营养不良患者、3例其他神经肌肉疾病患者(包括1例脂质沉积性肌病、2例运动神经元病)及5例正常对照者的骨骼肌标本进行Dystrophin蛋白免疫组化染色。结果 Duchenne型肌营养不良(DMD)患者肌细胞膜上无显色,Becker型肌营养不良(BMD)患者全部为弱阳性,BMD/LGMD(肢带型肌营养不良)患者中6例肌细胞膜上显色浅淡、不连续或呈斑片状,其余15例患者肌细胞膜上染色正常;2例运动神经元病患者中1例肌细胞膜显色浅淡、呈斑片状,另1例染色正常。脂质沉积性肌病患者和正常对照肌细胞膜上染色均正常。结论对于存在双下肢近端肌肉萎缩的临床表现相似的肌病患者,Dystrophin免疫组化染色可以将其大致区分,对早期预测肢体功能影响程度及正确地进行遗传咨询具有重要意义。

Differential Diagnostic Values of Dystrophin Expression in Atrophic Myopathy

Objective To explore the expression and clinical significance of Dystrophin in atrophic myopathy. Methods Dystrophin expression was detected by immunohistochemical staining in muscle tissues from 5 normal controls and 46 patients with proximal muscle atrophy of lower limbs （43 patients with myodystrophy, 1 patient with lipid storage myopathy and 2 patients with motor neuron disease）. Results In patients with Duchenne muscular dystrophy （DMD）, the membrane of muscle cells showed no staining for dystrophin protein. In patients with Becker muscular dystrophy（BMD）, the membrane of muscle cells showed weak staining for dystrophin protein. Among patients with BMD/LGMD （limb- girdle muscular dystrophy）, 6 showed light, discontinuous or patchy staining and 15 showed negative staining for Dystrophin protein. Among the 2 patients with motor neuron disease, 1 showed light and patchy staining and 1 showed negative staining for Dystrophin protein. In the patient with lipid storage myopathy and normal subjects, the membrane of muscle cells showed negative staining for Dystrophin protein. Conclusion The immunohistochemical staining for Dystrophin can differentiate myopathy patients with proximal muscle atrophy of lower limbs. Therefore, it has important significance for early prediction of limb function and correct genetic counseling.