An 18-year-old man is evaluated because of a 2-day history of fever, chills, and migratory arthralgias involving the ankles, knees, elbows, and shoulders. On physical examination there are subcutaneous nodules on the volar surface of both forearms, and a grade 2/6 systolic murmur and an S3 heard at the left ventricular apex. There is no objective evidence of joint disease.
Which of the following additional findings establishes a definite diagnosis of acute rheumatic fever in this patient?
( A ) Arthritis
( B ) Erythema marginatum
( C ) Choreoathetosis
( D ) An elevated erythrocyte sedimentation rate
( E ) A throat culture positive for group A streptococci