chorea or St. Vitus's dance, acute disturbance of the central nervous system characterized by involuntary muscular movements of the face and extremities. The disease, known also as Sydenham's chorea (not to be confused with Huntington's disease, a hereditary disease of adults that is sometimes called Huntington's chorea), is usually, but not always, a complication of rheumatic fever. Sydenham's chorea, a disease of children, especially females, usually appears between the ages of 7 and 14. Facial grimacing and jerking movements persist for 6 to 10 weeks and sometimes recur after months or even years. Eventually the symptoms disappear. Although there is no specific treatment, sedatives and tranquilizers are helpful in suppressing the involuntary movements. Technically, it is sometimes called chorea minor or juvenile chorea to distinguish it from several less common choreas, chorea also being a general term for continuous, involuntary jerking movements.

Sydenham's chorea: see chorea.

Neurological disorder causing irregular, involuntary, purposeless movements. It is believed to be caused by degeneration of the basal ganglia in the cerebral cortex. Sydenham chorea (St. Vitus dance) is usually associated with rheumatic fever. It usually occurs between ages 5 and 15, more often in girls. Typical jerking movements, mostly in the extremities and face, may affect speech and swallowing and range from mild to incapacitating; attacks last several weeks and recur frequently. Senile chorea, a progressive disease resembling Sydenham chorea, usually occurs late in life. Huntington chorea is rare, hereditary, and fatal. It usually begins between ages 35 and 50 and progresses to random, often violent, and eventually totally incapacitating spasms, absent only during sleep. Mental deterioration begins later, and death occurs in 10–20 years. There is no effective therapy. Children of those afflicted have a 50percnt chance of developing the illness.

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