What is Sydenham’s Chorea?
Sydenham’s chorea is a disease affecting the brain. ‘Chorea’ refers to a type of abnormal movements. Sydenham’s chorea happens after a childhood infection because of a problem with the body’s immune response to a common infection. Sydenham’s chorea can develop up to six months after a child has had an infection. Not all children have a clear history of having had an infection by a bacteria called Streptococcus. Most people who might develop Sydenham’s chorea do so before they reach eighteen years of age. It is more common in girls than boys. Sydenham’s chorea is part of a wider group of inflammatory responses called rheumatic fever, that may involve other parts of the body including the skin, joints and heart.
The word “chorea” is derived from the Greek word khoreia meaning “dance”. The involuntary movements sometimes resemble a dance; St. Vitus, a fourth century Sicilian martyr, was the patron saint of dancers. St. Vitus’s Dance is also known as Sydenham’s chorea, after the 17th century English physician Thomas Sydenham (1624-1689).
What causes it?
The infection is caused by a type of bacteria called Streptococcus. In some children, the immune system reacts in an unusual way to this infection. It affects cells in parts of a child’s brain called the basal ganglia. These are a collection of brain cells located deep within the brain and have a role in controlling movement and emotional responses. We do not know the reason why this happens but a risk of Sydenham’s chorea can run in families.
What are the symptoms?
A movement disorder comes on over a period of hours to days with uncoordinated jerking movements in the arms, hands, legs, feet and face. These movements are called chorea. Sometimes the chorea only involves one side of the body.
Behaviour changes, like changes in mood and behaviour, fatigue and restlessness.
The movement disorder (chorea) almost always settles down either on its own or with the help of medication.
Physical symptoms may include loss of fine and gross motor skills, loss of muscle tone, motor and speech difficulties, abnormal patterns of walking, facial grimacing and headache. Some children go on to develop a different kind of movement problem – they may make movements or sounds that they cannot control (often described as “tics”). Other physical symptoms may include inflammation of the heart, and joint pain.
How is it diagnosed?
There is no definite test for Sydenham’s chorea. Your General Practitioner (GP), a paediatrician or doctor at an A&E department may make the diagnosis after reviewing your symptoms and a physical examination. They may take a blood sample or throat swab to look for signs of a streptococcal infection. Once Sydenham’s chorea has been suspected you may be referred to a specialist paediatric doctor called a neurologist who will further assess you.
How is it treated?
Most doctors will try to treat any streptococcal infection by prescribing a course of penicillin followed by a lower dose of this drug to prevent a return of this bacteria. You may need to take penicillin until 18 years old – this is to prevent the development of inflammation of the heart.
The neurologist may try to treat the movement disorder with medication if it is causing problems for your activities of daily living.
Adam is a 10 year old boy who 6 months ago had a sore throat which he recovered from completely however recently he’s noticed that he’s become a bit clumsier, dropping things, his teachers have noticed that his previously neat hand writing has become quite messy and difficult to read. He’s noticed that he’s had trouble concentrating in class. Yesterday he was having a drink of water and his arm suddenly, involuntarily and uncontrollably jerked causing him to spill his drink. His mum took him to the GP today who said that he may have Sydenham’s chorea.