Snapshot A 42-year-old woman presents to her primary care physician for fatigue. She reports that her fatigue is worse towards the end of the day. She also notes that while bathing her nephew in the shower her head would "drop." At times when she is watching television or reading a book she sees double. Lastly, she would see her left or right eyelid droop after returning from work. On physical exam, there is right-sided ptosis after sustaining upward gaze for a few minutes. A tensilon test is performed, which is demonstrated in the clinical image below. Serologic studies return positive for anti-acetylcholine receptor antibodies. Preparations are made to have a computerized tomography scan of the chest. Introduction Clinical definition login to view 1 more bullet Epidemiology login to view 8 more bullets Pathogenesis login to view 8 more bullets Associated conditions login to view 2 more bullets Prognosis login to view 1 more bullet Presentation Symptoms login to view 15 more bullets Physical exam login to view 12 more bullets Imaging Computerized tomography (CT) scan login to view 4 more bullets Studies Labs login to view 4 more bullets Electromyogram (EMG) login to view 1 more bullet Differential Lambert-Eaton myasthenic syndrome (LEMS) login to view 3 more bullets Botulism login to view 2 more bullets Thyroid ophthalmopathy Treatment Medical login to view 15 more bullets Procedural login to view 3 more bullets Surgical login to view 3 more bullets Complications Myasthenic crisis login to view 1 more bullet Increased sensitivity to non-depolarizing acetylcholine receptor blockers such as vecuronium