A 24-year-old woman presents to ophthalmology clinic with 2 days of visual loss in her right eye. She had lost vision in the same eye 1 year previously, with recovery to about 70%. Her past medical history is otherwise unremarkable. She denies other episodes of nervous system dysfunction but on review of systems admitted to urinary urgency and tingling in her feet. On examination, her pupils are symmetrical and react briskly to light, but the right pupil dilates when the light is moved quickly from the left pupil to the right. Visual acuity is 20/25 left eye and 20/100 right eye. Funduscopic examination demonstrates pallor of the right optic disc; visual fields to confrontation appeared intact; cursory neurologic examination in the eye clinic is reported as normal. Long-term treatment will most likely be influenced by the results of which of the following antibody titer laboratory tests?
A. anti-acetylcholine receptor B. anti-aquaporin-4 C. antinuclear D. antiparietal cell E. thyroid peroxidase
