What is sydenham chorea?
Sydenham chorea is an acute neurologic disorder that emerges several months following a streptococcal ("strep") infection, most frequently in children between the age of 5 and 15. There may be a history of a strep throat or a strep skin infection. There may similarly be a history of another sequel of a strep infection such as scarlet fever, glomerulonephritis
or, especially, rheumatic fever.
Sydenham's chorea is a disorder that occurs in children and is associated with rheumatic fever. Rheumatic fever is an acute infectious disease caused by certain types of streptococci bacteria. It usually starts with strep throat or tonsillitis. These types of streptococci are able to cause disease throughout the body. The most serious damage caused by rheumatic fever is to the valves in the heart. At one time, rheumatic fever was the most common cause of damaged heart valves, and it still is in most developing countries around the world. Rheumatic fever and rheumatic heart disease are still present in the industrialized countries, but the incidence has dropped substantially. There are various forms of Sydenham chorea: one form that just involves one side of the body (hemichorea), another form that involves muscular rigidity (termed paralytic chorea), etc. Sydenham chorea is also known as acute chorea, chorea minor, juvenile chorea, rheumatic chorea and postrheumatic chorea.
Rheumatic fever may appear in several different forms. Sydenham's chorea is one of five "major criteria" for the diagnosis of rheumatic fever. There are also four "minor criteria" and two types of laboratory tests associated with the disease. The "Jones criteria" define the diagnosis. They require laboratory evidence of a streptococcal infection plus two or more of the criteria. The laboratory evidence may be identification of streptococci from a sore throat or antibodies to streptococcus in the blood. The most common criteria are arthritis and heart disease, occurring in half to three-quarters of the patients. Sydenham's chorea, characteristic nodules under the skin, and a specific type of skin rash occur only 10% of the time.