Soong B W, Lin K P
Department of Neurology, National Yang-Ming University School of Medicine, Taiwan, ROC.
Zhonghua Yi Xue Za Zhi (Taipei). 1998 Apr;61(4):181-7.
Machado-Joseph disease (MJD) is characterized by cerebellar ataxia, pyramidal signs, progressive external ophthalmoplegia, and variable degrees of bulging eyes and dystonia. Electrophysiologic and histologic alterations of the peripheral nervous system in patients with MJD have rarely been reported.
The peripheral nerves of four patients with MJD who were identified by polymerase chain reaction were subjected to electrophysiologic testing and histologic study. Correlation analyses were made between clinical parameters and the electrophysiologic as well as histologic changes.
Electrophysiologic studies demonstrated a marked reduction of sensory action potential, as well as a decrease in the compound motor action potential. Light microscopy of the sural nerves revealed marked loss of myelinated fibers, and morphometry studies showed a loss of large myelinated fibers. The severity of these pathologic changes was not related to the duration of the disease.
In MJD, the peripheral nervous system was frequently affected. These findings were similar to those seen in Friedreich's ataxia, suggesting a loss of sensory and motor fibers probably following a lesion of the dorsal root ganglion and the anterior horns in the spinal cord.
马查多-约瑟夫病（MJD）的特征为小脑共济失调、锥体束征、进行性眼外肌麻痹以及不同程度的突眼和肌张力障碍。MJD患者外周神经系统的电生理和组织学改变鲜有报道。
对4例经聚合酶链反应确诊的MJD患者的外周神经进行电生理检测和组织学研究。对临床参数与电生理及组织学变化进行相关性分析。
电生理研究显示感觉动作电位明显降低，复合运动动作电位也降低。腓肠神经的光镜检查显示有髓纤维明显丢失，形态计量学研究表明大的有髓纤维丢失。这些病理改变的严重程度与病程无关。
在MJD中，外周神经系统常受影响。这些发现与弗里德赖希共济失调所见相似，提示感觉和运动纤维的丧失可能是由于脊髓背根神经节和前角受损所致。
