Persistent Sydenham's chorea

BACKGROUND: Sydenham's chorea (SC) occurs in 26% of patients with rheumatic fever (RF). Despite usually being described as a self-limited condition, few reports indicate that SC may persist in rare subjects. OBJECTIVE: To investigate the proportion of subjects with SC lasting more than 2 years and if clinical features differentiate patients with SC with a duration of less than 2 years (Group 1) from those with SC lasting more than 2 years (Group 2). METHODS: Prospective assessment of all patients with SC seen at our service from July 1993 through March 1998 analyzing the following: gender; age at onset; frequency of arthritis, carditis, family history of RF and SC; topographic distribution; and chorea severity on a 0-4 scale. RESULTS: Thirty-two patients (19 female, 13 male) were studied. In Group 1 (16 subjects, 50%) the follow-up period was 36.2 +/- 20.0 months; 50% were female; age at onset was 10.9 +/- 2.6 years; arthritis and carditis were present in 37.5% and 31.2%, respectively; family history of SC was reported by 18.7%; hemichorea was seen in 25.8% of subjects; and the mean intensity of chorea was 2.6 +/- 0.8. In Group 2, with a follow-up period of 34.1 +/- 18.9 months, 68.8% were female; age at onset was 9.3 +/- 3.9 years; arthritis and carditis were diagnosed in 18.7% and 50%, respectively; no patient reported a family history of SC; hemichorea was observed in 6.2% of subjects; and the mean intensity of chorea was 2.8 +/- 0.5. No difference was statistically significant. CONCLUSIONS: SC persists in half of our patients. Female gender, possibly related to endocrine factors, as well as the presence of carditis, indicating a more severe disease, may be risk factors for a longer duration of SC.