Sydenham's Chorea.

Sydenham's chorea (SC) is a manifestation of acute rheumatic fever (ARF). Although the incidence of SC has declined significantly, particularly in developed areas, it remains the most common cause of acute chorea in children worldwide. Recent data show that SC accounts for almost all cases of chorea in children in the United States. As there is no specific laboratory marker of this condition, the diagnosis relies on a careful clinical history and laboratory assessment to rule out alternative causes. Morbidity is primarily related to cardiac lesions in ARF. It is recommended that all patients with suspected SC submit to a cardiologic evaluation. Neurologic features encompass motor signs, among which chorea is the most prominent, and nonmotor symptoms such as obsessive-compulsive behavior and attention-deficit/hyperactivity disorder. The first-line treatment of SC is valproic acid. Patients who do not respond to this drug or who present with severe chorea (particularly chorea paralytica, in which the muscle tone is so decreased that patients are bedridden) should be treated with risperidone. Other dopamine receptor-blocking drugs, such as haloperidol, may also be useful. There is growing evidence that immunosuppressive treatment, such as intravenous methylprednisolone followed by a tapering course of oral prednisone, is effective. This option has been used in patients who failed to respond to (or did not tolerate) the previously mentioned therapies. Plasmapheresis and intravenous immunoglobulin are regarded as experimental treatments. Obsessive-compulsive behavior associated with SC is not usually as severe as in other conditions such as Tourette's syndrome. Finally, because at least 20% of patients with SC experience recurrent attacks of ARF, they carry a high risk of developing severe cardiac lesions. These patients require prophylaxis against streptococcus infection, using penicillin or sulfa drugs.