QBANK A 29-year-old woman comes to your clinic with complaints of diffuse weakness for the past 3 months that seems to be getting worse. She has been in goo

[zahra.sham]

A 29-year-old woman comes to your clinic with complaints of diffuse weakness for the past 3 months that seems to be getting worse. She has been in good health, but over the past year has noted subtle changes in her ability to exercise to her usual capacity. She needed assistance to climb the stairs at home. Her weakness appears to worsen toward the end of the day. She has had occasional diplopia and difficulty chewing and swallowing her evening meals. She denies numbness or tingling or pain. On physical examination, the patient has normal vital signs. Her neurologic examination reveals normal cranial nerves. Her weakness is not apparent initially, but her muscles fatigue easily. Her sensation, reflexes, and cerebellar examination results are normal, as are the rest of her physical examination results.

Which is the most appropriate diagnostic test?

A. Muscle biopsy
B. Repetitive nerve stimulation testing
C. Anticholinesterase (tensilon) test
D. Anti-acetylcholine receptor antibodies
E. Single-fiber EMG