INSERM U974, Paris, France; CNRS FRE3617, Paris, France; Sorbonne Universités, UPMC Univ Paris 06, UM76, Paris, France; AIM, Institut de myologie, Paris, France.
INSERM U974, Paris, France; CNRS FRE3617, Paris, France; Sorbonne Universités, UPMC Univ Paris 06, UM76, Paris, France; AIM, Institut de myologie, Paris, France.
J Autoimmun. 2014 Feb-Mar;48-49:143-8. doi: 10.1016/j.jaut.2014.01.003. Epub 2014 Feb 13.
Myasthenia gravis is characterized by muscle weakness and abnormal fatigability. It is an autoimmune disease caused by the presence of antibodies against components of the muscle membrane localized at the neuromuscular junction. In most cases, the autoantibodies are against the acetylcholine receptor (AChR). Recently, other targets have been described such as the MuSK protein (muscle-specific kinase) or the LRP4 (lipoprotein related protein 4). Myasthenia gravis can be classified according to the profile of the autoantibodies, the location of the affected muscles (ocular versus generalized), the age of onset of symptoms and thymic abnormalities. The disease generally begins with ocular symptoms (ptosis and/or diplopia) and extends to other muscles in 80% of cases. Other features that characterize MG include the following: variability, effort induced worsening, successive periods of exacerbation during the course of the disease, severity dependent on respiratory and swallowing impairment (if rapid worsening occurs, a myasthenic crisis is suspected), and an association with thymoma in 20% of patients and with other autoimmune diseases such as hyperthyroidism and Hashimoto's disease. The diagnosis is based on the clinical features, the benefit of the cholinesterase inhibitors, the detection of specific autoantibodies (anti-AChR, anti-MuSK or anti-LRP4), and significant decrement evidenced by electrophysiological tests. In this review, we briefly describe the history and epidemiology of the disease and the diagnostic and clinical classification. The neonatal form of myasthenia is explained, and finally we discuss the main difficulties of diagnosis.
重症肌无力的特征是肌肉无力和异常疲劳。它是一种自身免疫性疾病，由位于神经肌肉接头处的肌肉膜成分的抗体引起。在大多数情况下，自身抗体是针对乙酰胆碱受体（AChR）的。最近，还描述了其他靶点，如 MuSK 蛋白（肌肉特异性激酶）或 LRP4（脂蛋白相关蛋白 4）。重症肌无力可根据自身抗体的特征、受影响肌肉的位置（眼肌型与全身型）、症状发作的年龄和胸腺异常进行分类。该疾病通常从眼肌症状（上睑下垂和/或复视）开始，80%的病例会扩展到其他肌肉。MG 的其他特征包括：波动性、用力加重、疾病过程中连续恶化期、严重程度取决于呼吸和吞咽功能障碍（如果迅速恶化，怀疑发生肌无力危象），以及 20%的患者与胸腺瘤和其他自身免疫性疾病如甲状腺功能亢进和桥本氏病相关。诊断基于临床特征、胆碱酯酶抑制剂的疗效、特定自身抗体（抗 AChR、抗 MuSK 或抗 LRP4）的检测以及电生理测试证实的明显递减。在这篇综述中，我们简要描述了疾病的历史和流行病学以及诊断和临床分类。解释了新生儿型重症肌无力，最后讨论了诊断的主要难点。
