指总伸肌单纤维肌电图对眼肌型重症肌无力的预测性预后评估：102例回顾性研究

Single-fiber Electromyography in the Extensor Digitorum Communis for the Predictive Prognosis of Ocular Myasthenia Gravis: A Retrospective Study of 102 Cases.

作者信息

Guan Yu-Zhou, Cui Li-Ying, Liu Ming-Sheng, Niu Jing-Wen

机构信息

Department of Neurology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing 100730; Neuroscience Center, Chinese Academy of Medical Sciences, Beijing 100730, China.

出版信息

Chin Med J (Engl). 2015 Oct 20;128(20):2783-6. doi: 10.4103/0366-6999.167354.

DOI:10.4103/0366-6999.167354

PMID:26481746

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC4736893/

Abstract

BACKGROUND

Single-fiber electromyography (SFEMG) abnormality in the extensor digitorum communis (EDC) was reported in ocular myasthenia gravis (OMG), which indicated subclinical involvement beyond extraocular muscles in OMG patients. The relationship between the abnormal findings of SFEMG in EDC and the probability for OMG to develop generalized myasthenia gravis (GMG) is unknown. This retrospective study aimed to determine the predictive value of abnormality of SFEMG in EDC of OMG patients.

METHODS

One-hundred and two OMG patients underwent standard clinical diagnosis process and SFEMG test in EDC muscle when diagnosed and were clinically followed up for 5 years. The SFEMG data were compared between different clinical groups according to thymus status, onset age, and different outcome of OMG developing. Chances of progressing to GMG were compared between two different groups according to SFEMG and repetitive nerve stimulation (RNS) results, acetylcholine receptor antibody (AchRAb) titer, thymus status, and onset age.

RESULTS

Abnormal SFEMG results were observed in 84 (82.4%) patients. The mean jitter, percentage of jitter >55 μs (%), and blocking were higher in OMG patients than in healthy volunteers. There were no statistical differences in jitter analysis between thymoma group and non-thymoma group (P = 0.65), or between the later OMG group and the later GMG group (P = 0.31), including mean jitter, percentage of jitter >55 μs (%), and blocking. Elderly group (≥45 years old) had a higher mean jitter than younger group (t = 2.235, P = 0.028). Total 55 OMG developed GMG, including 47 in abnormal SFEMG group while 8 in normal SFEMG group. There was no statistical difference in the conversion rates between the two groups (χ2 = 0.790, P = 0.140). RNS abnormality, AchRab titer, or onset age had no correlation with OMG prognosis (P = 0.150, 0.070, 0.120, respectively) while thymoma did (χ2 = 0.510, P = 0.020).

CONCLUSION

SFEMG test in the EDC showed high abnormality in OMG, suggesting subclinical involvement other than extraocular muscles. Nevertheless, the abnormal jitter analysis did not predict the prognosis of OMG according to clinical follow-up.

摘要

背景

眼肌型重症肌无力（OMG）患者的指总伸肌（EDC）单纤维肌电图（SFEMG）异常，提示OMG患者存在眼外肌以外的亚临床受累。EDC的SFEMG异常表现与OMG发展为全身型重症肌无力（GMG）的可能性之间的关系尚不清楚。这项回顾性研究旨在确定OMG患者EDC的SFEMG异常的预测价值。

方法

102例OMG患者在确诊时接受了标准临床诊断流程及EDC肌肉的SFEMG检查，并进行了5年的临床随访。根据胸腺状态、发病年龄和OMG发展的不同结局，对不同临床组的SFEMG数据进行比较。根据SFEMG和重复神经电刺激（RNS）结果、乙酰胆碱受体抗体（AchRAb）滴度、胸腺状态和发病年龄，比较两组发展为GMG的可能性。

结果

84例（82.4%）患者的SFEMG结果异常。OMG患者的平均颤抖、颤抖>55μs的百分比（%）和阻滞高于健康志愿者。胸腺瘤组和非胸腺瘤组之间（P = 0.65），或晚发型OMG组和晚发型GMG组之间（P = 0.31），在颤抖分析方面无统计学差异，包括平均颤抖、颤抖>55μs的百分比（%）和阻滞。老年组（≥45岁）的平均颤抖高于年轻组（t = 2.235，P = 0.028）。共有55例OMG发展为GMG，其中SFEMG异常组47例，SFEMG正常组8例。两组之间的转化率无统计学差异（χ2 = 0.790，P = 0.140）。RNS异常、AchRab滴度或发病年龄与OMG预后无相关性（P分别为0.150、0.070、0.120），而胸腺瘤与预后相关（χ2 = 0.510，P = 0.020）。