CASE

Myasthenia Gravis: Neuromuscular Transmission

Wendy Chu is a 23-year-old photographer for a busy local newspaper. Over the last 8 months, she experienced strange symptoms. She had severe eyestrain when she read for longer than 15 min. She became tired when she chewed her food, brushed her teeth, or dried her hair; and she had extreme fatigue on the job. Despite her strong work ethic, Wendy had to excuse herself from several shoots because she simply could not carry the heavy equipment. Wendy is not a complainer, but she began to worry about these vague symptoms. She was evaluated by her physician, who suspected myasthenia gravis. While awaiting the results of a serum antibody test, the physician initiated a trial of pyridostigmine, an acetylcholinesterase inhibitor. Wendy immediately felt better while taking the drug; her strength returned to almost normal. Meanwhile, the results of the antibody test were positive, confirming the diagnosis of myasthenia gravis.