Sydenham Chorea
Involuntary jerky movements following streptococcal infection
Quick Facts
- Type: Neurological movement disorder
- Linked to: Rheumatic fever, strep infection
- Most affected: Children aged 5 to 15
- Outlook: Usually resolves over weeks to months
Overview
Sydenham chorea is a neurological disorder marked by rapid, irregular, involuntary movements that flow from one part of the body to another. It most often affects children between about 5 and 15 years of age and is one of the major features of rheumatic fever, an illness that can follow an untreated streptococcal (strep) throat infection.
The disorder develops when the immune system, while fighting the strep bacteria, mistakenly affects a part of the brain that controls movement. The movements can be distressing and may interfere with walking, writing, and speech, but Sydenham chorea is usually self-limiting and tends to improve over weeks to months. Because it is linked to rheumatic fever, it is important to identify and treat the underlying infection and protect the heart.
Symptoms
Symptoms usually appear gradually, often weeks to months after a strep infection. They include:
- Rapid, jerky, involuntary movements of the hands, arms, face, and trunk
- Clumsiness and difficulty with fine tasks such as writing or doing up buttons
- Slurred or hesitant speech
- Facial grimacing
- Muscle weakness or a loose, floppy feeling in the limbs
- Emotional changes such as irritability, mood swings, or restlessness
The movements often worsen with stress and disappear during sleep. Because the disorder is part of rheumatic fever, it may occur alongside joint pain, fever, or signs of heart involvement, which need medical evaluation.
Causes
Sydenham chorea is caused by an abnormal immune response following infection with group A streptococcus bacteria, the same bacteria that cause strep throat. In susceptible children, antibodies produced to fight the infection also react with the basal ganglia, a region of the brain that helps control movement. This is known as an autoimmune reaction.
The condition is one of the features of rheumatic fever, which can also affect the heart, joints, and skin. It is more common in areas where strep infections are not always promptly treated.
Risk Factors
- A recent untreated or undertreated strep throat infection
- Age between about 5 and 15 years
- Female sex, as it is somewhat more common in girls
- A personal or family history of rheumatic fever
- Living in areas where strep infections are not consistently treated
Diagnosis
Diagnosis is based mainly on the characteristic movements and a history of recent strep infection. Doctors may use:
- Clinical examination: Observing the typical chorea and checking for other signs of rheumatic fever.
- Throat culture or antibody tests: To find evidence of recent strep infection.
- Heart evaluation: An echocardiogram and examination to check for rheumatic heart involvement.
- Blood tests: To assess inflammation and help rule out other causes.
Other causes of chorea are considered and excluded as needed.
Treatment
Treatment addresses the movements, treats the underlying strep infection, and protects the heart.
- Antibiotics: To clear any remaining strep infection, with ongoing preventive antibiotics often recommended to guard against future rheumatic fever.
- Rest and a calm environment: Reducing stimulation can lessen the severity of movements.
- Medication for severe movements: When chorea is disabling, certain medicines can help control the movements.
- Treating rheumatic fever: Managing any heart or joint involvement is an important part of care.
- Monitoring: Follow-up to watch for recurrence and to protect the heart over the long term.
Most children recover fully over several weeks to months, though symptoms can sometimes recur.
Prevention
- Treat strep throat promptly and completely with the full course of antibiotics
- Seek care for sore throats with fever, especially in children
- Take long-term preventive antibiotics if recommended after rheumatic fever to prevent recurrence
- Attend follow-up visits to monitor the heart
When to See a Doctor
See a doctor promptly if a child develops new involuntary jerky movements, clumsiness, slurred speech, or unusual emotional changes, especially after a recent sore throat or fever. Seek urgent care if movements are severe and interfere with eating or safety, or if there are signs of heart involvement such as chest pain, breathlessness, or marked fatigue, as rheumatic fever can affect the heart.
Frequently Asked Questions
What causes Sydenham chorea?
It is caused by an abnormal immune reaction after a group A strep infection, the same bacteria behind strep throat. Antibodies meant to fight the infection also affect a movement-control area of the brain, causing the involuntary movements.
Is Sydenham chorea serious?
The chorea itself usually improves over weeks to months. The main concern is that it is part of rheumatic fever, which can damage the heart, so identifying and treating the underlying condition is important.
Does Sydenham chorea go away?
Yes, in most children the movements resolve over several weeks to months. Symptoms can sometimes recur, and long-term preventive antibiotics are often recommended to prevent future rheumatic fever.
How is Sydenham chorea treated?
Treatment includes antibiotics for the strep infection, rest, and sometimes medication to control severe movements. Managing any heart or joint involvement from rheumatic fever is also essential.
Can Sydenham chorea be prevented?
The best prevention is prompt, complete antibiotic treatment of strep throat to avoid rheumatic fever. After rheumatic fever, long-term preventive antibiotics may be advised to prevent recurrence.
References
- National Institute of Neurological Disorders and Stroke (NINDS). Sydenham chorea.
- Centers for Disease Control and Prevention (CDC). Rheumatic Fever.
- MedlinePlus, U.S. National Library of Medicine. Sydenham chorea.
- American Heart Association. Rheumatic fever and chorea.