Golden Sean K, Reiff Chris J, Painter Chris J, Repplinger Michael D
Department of Emergency Medicine, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin.
J Emerg Med. 2015 Jul;49(1):e23-5. doi: 10.1016/j.jemermed.2015.01.002. Epub 2015 Mar 19.
Myasthenia gravis (MG) is an autoimmune neuromuscular disorder that is classically characterized by fluctuating weakness and fatigability of the ocular, bulbar, limb, or respiratory muscles. Over half of patients with MG will initially experience isolated ocular symptoms in one or both eyes. Most patients report that ocular symptoms are mild or undetectable upon awakening, and worsen throughout the day or with tasks such as driving. We describe an unusual case of MG presenting with an acute onset of persistent unilateral ptosis and ipsilateral facial droop without diurnal variation or other fluctuation in severity.
A 58-year-old man presented to the Emergency Department with a 3-day history of persistent, unilateral ptosis with facial droop, concerning for stroke. However, magnetic resonance imaging of the head found no evidence of stroke or any other central etiology. Routine laboratory testing was unremarkable. Neurology was consulted and they recommended sending acetylcholine receptor antibody tests. At the patient's subsequent neurology clinic visit, these tests were found to be abnormal. Electromyography was also done at this visit, confirming the diagnosis of MG. The patient subsequently underwent thymectomy and immunosuppressive therapy, with great improvement in his symptoms. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: MG may present as unilateral ptosis or facial drooping without the hallmark characteristic of fluctuating muscle weakness. Early diagnosis and subsequent treatment of MG improves long-term prognosis and remission rates. Emergency physicians should consider myasthenia gravis in cases of unilateral ocular symptoms after ruling out emergent central etiologies.
重症肌无力（MG）是一种自身免疫性神经肌肉疾病，其典型特征是眼肌、延髓肌、肢体肌或呼吸肌出现波动性无力和疲劳感。超过半数的MG患者最初会仅出现单眼或双眼的孤立性眼部症状。大多数患者报告称，眼部症状在醒来时较轻或难以察觉，而在一天中或进行如驾驶等活动时会加重。我们描述了一例不寻常的MG病例，其表现为急性起病的持续性单侧上睑下垂和同侧面部下垂，且严重程度无日间变化或其他波动。
一名58岁男性因持续3天的持续性单侧上睑下垂伴面部下垂前往急诊科就诊，怀疑为中风。然而，头部磁共振成像未发现中风或任何其他中枢性病因的证据。常规实验室检查无异常。咨询了神经科，他们建议进行乙酰胆碱受体抗体检测。在患者随后的神经科门诊就诊时，发现这些检测结果异常。此次就诊时还进行了肌电图检查，确诊为MG。患者随后接受了胸腺切除术和免疫抑制治疗，症状有了很大改善。急诊医生为何应了解此情况？：MG可能表现为单侧上睑下垂或面部下垂，而无波动性肌无力这一标志性特征。MG的早期诊断及后续治疗可改善长期预后和缓解率。排除紧急中枢性病因后，急诊医生在出现单侧眼部症状的病例中应考虑重症肌无力。
