DescriptionSydenham chorea, also called St. Vitus dance, is a childhood movement disorder characterised by rapid, irregular, aimless, involuntary movements of the muscles of the limbs, face and trunk.
The disorder, which is considered a manifestation of rheumatic fever (streptococcal infection), typically has an onset between the ages of 5 and 15. Girls are affected more often than boys.
The chorea is believed to result from an autoimmune mechanism that occurs when the streptococcal infection causes the body to make antibodies to specific brain regions.
SymptomsThe symptoms may appear gradually or suddenly and may include muscle weakness, hypotonia (decreased muscle tone) and clumsiness.
The symptoms vary in severity - from mild cases in which there is restlessness, facial grimacing and a slight degree of incoordination of movements, to severe cases involving involuntary movements that incapacitate the child.
The disorder may strike up to six months after the fever or infection has cleared.
PrognosisGenerally the prognosis for patients with Sydenham chorea is good and complete recovery often occurs. The duration of the disorder varies, with the average case lasting three to six weeks. Occasionally the course may be prolonged for several months.
TreatmentThere is no specific treatment for Sydenham chorea. Treatment is symptomatic and may include bed rest, sedatives and the drug diazepam for controlling movements.
Penicillin may also be prescribed for treatment of the fever or infection. Penicillin prophylaxis is often prescribed to avoid further infections with streptococcal bacteria.
(Reviewed by Dr Andrew Rose-Innes, Department of Neurology, Yale University School of Medicine)