Chorea minor


Sydenham's chorea is an acute but self-limited movement disorder that occurs most commonly in children between the ages of 5 and 15, and occasionally in pregnant women. It is closely associated with rheumatic fever following a throat infection. The disorder is named for Thomas Sydenham (1624-1689), an English doctor who first described it in 1686. Other names for Sydenham's chorea include simple chorea, chorea minor, acute chorea, rheumatic chorea, juvenile chorea, and St. Vitus' dance.


* frequent mood changes * episodes of uncontrollable crying * behavioral regression; that is, acting like much younger children * mental confusion * general irritability * difficulty concentrating * impulsive behavior


Sydenham's is caused by certain types of streptococci called Group A beta-hemolytic streptococci or GAS bacteria. In general, streptococci are spherical-shaped anaerobic bacteria that occur in pairs or chains. GAS bacteria belong to a subcategory known as pyogenic streptococci, which means that the infections they cause produce pus. These particular germs seem to be able to create an immune response that attacks the body's own tissues along with the germs. Those tissues are joints, heart valves, skin, and brain.


All cases of strep throat in children should be treated with a full 10 days of antibiotics (penicillin or erythromycin). Treatment may best be delayed a day or two to allow the body to build up its own antibodies. In addition, for those who have had an episode of rheumatic fever or have damaged heart valves from any other cause, prophylactic antibiotics should be continued to prevent recurrence.


The diagnosis of Sydenham's is also based on the doctor's observation of the patient's involuntary movements. Unlike tics, the movements associated with chorea are not repetitive; and unlike the behavior of hyperactive children, the movements are not intentional. The recent onset of the movements rules out a diagnosis of cerebral palsy.


Syndenham's chorea usually clears up without complications when the rheumatic fever is treated. The heart valve damage associated with rheumatic fever may lead to heart trouble and require a surgical valve repair or replacement.


Suspected streptococcal infections must be treated. All the other manifestations of rheumatic fever, including Sydenham's chorea and excluding heart valve damage, remit with the acute disease and do not require treatment. Sydenham's chorea generally lasts for several months.