Review Question - QID 202946

A 55-year-old caucasian man presents to his primary care physician with a complaint of double vision, which started suddenly with no precipitating trauma. Twelve years ago, he presented to his physician with painful vision loss, which has since resolved. Since that initial episode, he had numerous episodes early-on in his disease course: two additional episodes of painful vision loss, as well as three episodes of right arm weakness and three episodes of urinary retention requiring catheterization. All of his prior episodes responded to supportive therapy and steroids. Which of the following features of this patient's disease is linked to a more benign disease course?