A clinical study of Sydenham s chorea at University Malaya Medical Centre

This is a retrospective clinical study of Sydenham’s chorea admitted to the University Malaya Medical Centre from 1967 to 1997. Three hundred and thirteen patients with acute rheumatic fever were identified. Sydenham’s chorea was seen in 12% (37/313) of the patients. The mean age of onset of chorea was 11.5 years (range 2-21 years). The overall male to female ratio was 1.01:1, with a female preponderance among patients greater than 12 years of age. There was a disproportionate predominance of ethnic Indians among patients with acute rheumatic fever as well as Sydenham’s chorea. Of the patients with Sydenham’s chorea, 65% (24/37) were isolated chorea where there was no other major criteria of acute rheumatic fever. The overall trend was a decline in incidence of acute rheumatic fever over the study period. On the other hand, there were peaks in the incidence of isolated chorea. Isolated chorea was also associated with less frequently raised antistreptolysin O titer, higher recurrence rate, equal sexual predilection, and no development of rheumatic valvular disease after seven years of follow-up, as compared with other patients with mixed chorea, where there was major criteria of acute rheumatic fever. Conclusions: The lack of correlation between the incidence trend of isolated chorea and acute rheumatic fever, with differences in the features of isolated chorea as compared to mixed chorea suggested that some cases of isolated chorea were of non-rheumatic etiology.