A 56-year-old man with 60-pack-year history of smoking presents to the physician for a 3-month history of progressive fatigue. He says that the past few weeks it has been more difficult for him to walk up the stairs at home and comb his hair due to muscle fatigue. Physical examination shows no impairment of upward gaze for 60 seconds. This patient’s condition most closely resembles the effects of which of the following toxins?
Botulinum
Diphtheria
Enterotoxigenic E. coli heat-labile
Enterotoxigenic E. coli heat-stable
Tetanus
