Department of Neurology, Division of Child Neurology and Neuromuscular Disease Research Laboratory, Mayo Clinic College of Medicine, Mayo Clinic, Rochester, MN, USA.
Neuromuscul Disord. 2011 Mar;21(3):161-71. doi: 10.1016/j.nmd.2010.12.007. Epub 2011 Jan 20.
Myofibrillar myopathies represent a group of muscular dystrophies with a similar morphologic phenotype. They are characterized by a distinct pathologic pattern of myofibrillar dissolution associated with disintegration of the Z-disk, accumulation of myofibrillar degradation products, and ectopic expression of multiple proteins and sometimes congophilic material. The clinical features of myofibrillar myopathies are more variable. These include progressive muscle weakness, that often involves or begins in distal muscles but limb-girdle or scapuloperoneal distributions can also occur. Cardiomyopathy and peripheral neuropathy are frequent associated features. EMG of the affected muscles reveals myopathic motor unit potentials and abnormal irritability often with myotonic discharges. Rarely, neurogenic motor unit potentials or slow nerve conductions are present. The generic diagnosis of myofibrillar myopathies is based on muscle biopsy findings in frozen sections. To date, all myofibrillar myopathy mutations have been traced to Z-disk-associated proteins, namely, desmin, αB-crystallin, myotilin, ZASP, filamin C and Bag3. However, in the majority of the myofibrillar myopathy patients the disease gene awaits discovery.
肌原纤维肌病是一组具有相似形态表型的肌肉疾病。它们的特征是肌原纤维溶解的明显病理模式，与 Z 盘的崩解、肌原纤维降解产物的积累、多种蛋白质的异位表达以及有时嗜刚果红物质有关。肌原纤维肌病的临床特征更为多变。这些包括进行性肌肉无力，通常涉及或始于远端肌肉，但也可能发生肢体带或肩胛带分布。常伴有心肌病和周围神经病。受累肌肉的肌电图显示肌病性运动单位电位和异常兴奋性，常伴有肌强直性放电。很少见神经原性运动单位电位或缓慢的神经传导。肌原纤维肌病的一般诊断基于冷冻切片的肌肉活检结果。迄今为止，所有肌原纤维肌病的突变都已追踪到与 Z 盘相关的蛋白，即结蛋白、αB-晶体蛋白、肌球蛋白、ZASP、细丝蛋白 C 和 Bag3。然而，在大多数肌原纤维肌病患者中，疾病基因仍有待发现。
