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Sydenham's chorea Syd·en·ham's chorea (sĭd'n-əmz)
An acute toxic or infective disorder of the nervous system, usually associated with acute rheumatic fever, occurring in young persons and characterized by involuntary, irregular, jerky movement of the muscles of the face, neck, and limbs. Also called Saint Vitus' dance.
a neurological disorder characterized by irregular and involuntary movements of muscle groups in various parts of the body that follow streptococcal infection. The name St. Vitus Dance derives from the late Middle Ages, when persons with the disease attended the chapels of St. Vitus, who was believed to have curative powers. The disorder was first explained by the English physician Thomas Sydenham. Most often a manifestation of rheumatic fever, Sydenham chorea occurs most frequently between the ages of 5 and 15 years, and is more common in girls than boys. The disease may occur as an infrequent complication of pregnancy.