Sydenham's chorea (SC) is a disorder of the central nervous system (CNS) characterized by sudden, involuntary, arrhythmic, clonic, and purposeless movements. These are associated with hypotonia, motor failure, and psychological symptoms, as well as difficulties of speech and gait. SC commences in infancy or puberty and has a tendency to relapse.
The term chorea derives from the Greek word for dancing, and has been used to describe the abnormal movements seen in SC, as well as the disorder itself. This has led to a certain confusion in the literature. Three important points in time can be highlighted in the history of SC: its initial description in 1686; its proposed link with rheumatic fever (RF) in the 1860s12; and the recent developments, since the 1980s, emphasizing its relationship with other psychiatric disorders.
SC was first described by Thomas Sydenham, in his Schedula Monitoria in 1686. He named this new disease “St. Vitus' Dance” to differentiated it from “dancing mania,” a practice seen in the religious ceremonies of the day by those who danced to exorcise prevalent epidemic illnesses.8 Sydenham's clinical description was fairly complete, but at that time he attributed the illness to physical trauma and emotional shock.
In 1780, Stoll described two cases that seemed to suggest an association between arthritis and chorea. This relationship was better established by Roger, in his articles of 1866 and 1868.12 Although the North American literature began to discuss the association between SC and RF at the beginning of this century,18 it seemed to take much longer for these concepts to be accepted in other countries. For example, SC was discussed more phenomenologically than causally in the French literature during the 1920s.56 Even in the 1970s, however, doubts were being expressed about its links with RF, particularly in the absence of rheumatic symptoms, such as arthritis, carditis, or elevated erythrocyte sedimentation rate.2 Nevertheless, the increasing evidence of an association with RF has led to SC also being called rheumatic chorea or chorea minor.52, 59 During the second half of this century, SC and RF have been associated with the occurrence of an antecedent group A β-streptococcal infection.58
SC more recently has been linked to the obsessive-compulsive disorder (OCD) spectrum. Informal descriptions had suggested that postchoreic tic, coprolalia, and impulsive behavior were sequelae of SC.5 More systematic studies began to demonstrate a high incidence of obsessive-compulsive symptoms (OCS), as well as OCD in SC children.64 Although some investigators attempted to associate SC with other psychiatric disorders such as schizophrenia,21, 39 these efforts have been less successful.
The purpose of this article is to provide an overview of the clinical picture, causes, course, and treatment of SC, as well as to examine some pathophysiologic hypotheses, and its relationship to psychiatric disorders.