线粒体肌病与其它神经肌病破碎红纤维的对比研究

A comparative study of ragged red fibers between mitochondrial myopathy and other neuromuscular disorders

为了探讨破碎红纤维（ＲＲＦｓ）对线粒体肌病的诊断价值，对线粒体肌病、多发性肌炎／皮肌炎（ＰＭ／ＤＭ）和脊髓性肌萎缩（ＳＭＡ）３组病人ＲＲＦｓ的形态特点和出现频率进行了对比研究，同时对３组病人线粒体的超微结构改变进行了对比观察。结果发现总ＲＲＦｓ出现频率线粒体肌病组３．０％～１５．２％，ＰＭ／ＤＭ组５．２％～１１．１％，ＳＭＡ组４．５％～４９％。线粒体肌病组以典型ＲＲＦｓ为主，ＰＭ／ＤＭ组以均匀红染纤维为主，ＳＭＡ组以红边纤维为主。线粒体的超微结构观察发现线粒体肌病组线粒体形态改变、嵴排列异常及嵴内包涵体多见，受累线粒体较多。ＰＭ／ＤＭ组和ＳＭＡ组线粒体主要改变是数量增多，形态变小，而外形改变和嵴排列异常少见。未见嵴内包涵体。本研究结果提示ＲＲＦｓ及出现频率不能作为诊断线粒体肌病的形态学标准，典型ＲＲＦｓ对线粒体肌病的诊断较有价值。

The morphological features and frequency of RRFs and ultrastructural alterations of mitochondrial myopathy,PM/DM and SMA were compared to evaluate the diagnostic value of RRFs.In this study,RRFs were defined as fibers with redstained accumulation beneath sarcolemmal or between myofibrils.All RRFs were divided into 3 types according to morphological features,i .e.typical RRFs,rededged fibers and homogeneous red fibers.The results showed typical RRFs were more frequently found in mitochondrial myopathy,rededged fibers were more frequently in SMA group,and homogenous rededged fibers were more frequently in PM/DM group.Ultrastructural alterations of mitochondria in mitochondrial myopathy included abnormal shape,disarrangment of cristae and intracristal inclusions in a quite number of mitochondria.In PM/DM and SMA group,the increased number of small mitochondrial was commonly seen.This investigation suggested that only typical RRFs might have a significant value for the diagnosis of mitochondrial myopathy.