Department of Pharmacy, University of Patras, GR 26500, Patras, Greece.
J Neuroimmunol. 2012 Sep 15;250(1-2):94-8. doi: 10.1016/j.jneuroim.2012.05.011. Epub 2012 Jun 9.
Myasthenia gravis (MG) is an autoimmune disorder of the neuromuscular junction usually caused by antibodies to the nicotinic acetylcholine receptor (AChR) and occasionally to muscle-specific kinase (MuSK). D-penicillamine is a therapeutic agent for several diseases, but can also induce a number of immune-mediated disorders, including MG, as a side-effect. In most patients with D-penicillamine-induced MG, anti-AChR antibodies are detected, but the presence of anti-MuSK antibodies has not been reported previously.
The case reported was a female patient who presented with myasthenic symptoms after D-penicillamine administration for scleroderma.
Both anti-AChR and anti-MuSK antibodies were identified in the patient's serum. The anti-MuSK antibodies were of the IgG4 subclass, as in idiopathic MG. Both types of antibody gradually disappeared after discontinuation of D-penicillamine. A significant improvement in symptoms was observed and the patient gradually became free of MG symptoms, without requiring any treatment for MG. Another four double-positive (anti-AChR and anti-MuSK antibodies) patients were identified during a retrospective study, but none had been treated with D-penicillamine.
D-penicillamine can cause anti-AChR and anti-MuSK antibody-positive MG, a rare phenomenon which is reversed after discontinuation of D-penicillamine treatment.
重症肌无力（MG）是一种神经肌肉接头的自身免疫性疾病，通常由乙酰胆碱受体（AChR）抗体引起，偶尔也由肌肉特异性激酶（MuSK）抗体引起。青霉胺是几种疾病的治疗药物，但也可引起多种免疫介导的疾病，包括作为副作用的 MG。在大多数青霉胺诱导的 MG 患者中，可检测到抗 AChR 抗体，但以前没有报道过抗 MuSK 抗体的存在。
该病例报告的是一名女性患者，在因硬皮病使用青霉胺治疗后出现肌无力症状。
在患者的血清中同时检测到抗 AChR 和抗 MuSK 抗体。抗 MuSK 抗体为 IgG4 亚类，与特发性 MG 相同。两种类型的抗体在停用青霉胺后逐渐消失。观察到症状显著改善，患者逐渐摆脱了 MG 症状，无需任何 MG 治疗。在回顾性研究中还发现了另外 4 例双阳性（抗 AChR 和抗 MuSK 抗体）患者，但均未接受青霉胺治疗。
青霉胺可引起抗 AChR 和抗 MuSK 抗体阳性的 MG，这是一种罕见现象，停药后可逆转。
