Sydenham Chorea

What Causes Sydenham Chorea?

Scientists believe that Sydenham chorea is an autoimmune disorder in which the immune system mistakenly attacks the body’s healthy cells. They are not sure exactly why the condition is associated with a strep infection. They suspect that strep bacteria have something in common with specific normal cells, leading the immune system to mistake the cells for bacteria.

The immune reaction that causes SC commonly affects cells in the heart, kidneys, and joints. It also affects cells in the area of the brain that controls movement; this is the likely cause of SC.

Is Sydenham Chorea Hereditary?

Some types of chorea, such as Huntington’s disease, have a genetic component and may be inherited. However, because it occurs due to a bacterial infection, Sydenham chorea is considered an acquired condition. Researchers believe that some people may have a genetic predisposition that makes them vulnerable to autoimmune conditions such as SC, but a definite genetic link to the disorder has not yet been discovered.

How Is Sydenham Chorea Detected?

Sometimes doctors don’t recognize Sydenham chorea immediately. In some cases, parents don’t know that the child has had a bacterial infection, and the chorea is the only sign that something is wrong. Doctors may misdiagnose the condition as behavioral as a result.

Symptoms of SC that might be misinterpreted include:

• Grimacing
• Fidgeting
• Clumsiness
• Apparent oppositional or emotional behavior

How Is Sydenham Chorea Diagnosed?

Chorea is rare in children, so doctors may suspect Sydenham chorea if a child has an onset of choreic symptoms with no other apparent cause. The diagnostic process will typically include tests to look for a bacterial infection, rule out other causes of the symptoms, and look for signs of potential complications.

Diagnostic steps may include:

• Throat swabs or blood tests to detect antibodies that indicate a bacterial infection
• Imaging scans such as magnetic resonance imaging (MRI) to rule out other neurological causes of the symptoms
• Exams to rule out heart inflammation commonly associated with rheumatic fever

PLEASE CONSULT A PHYSICIAN FOR MORE INFORMATION.

How Is Sydenham Chorea Treated?

In most cases, the symptoms of Sydenham chorea resolve on their own in a few weeks without treatment. If symptoms are severe or persistent, treatment may be recommended.

Treatment options include:

• Anti-seizure drugs such as  valproic acid, diazepam, chlorpromazine, and carbamazepine
• Steroids such as prednisone
• Dopamine-blocking drugs such as haloperidol or tetrabenazine
• Antibiotics to prevent future infections and recurrence of symptoms. Long-term treatment with penicillin until adulthood is usually recommended.

How Does Sydenham Chorea Progress?

The symptoms of Sydenham chorea usually go away within weeks, but they may persist for up to two years. In about a third of cases, SC recurs within a few years after the first episode. Some researchers believe that treatment with antibiotics may decrease the likelihood of recurrence.

Some studies have suggested a link between recurrent Sydenham chorea and several mental disorders. These disorders are referred to as pediatric autoimmune neuropsychiatric disorders associated with streptococcus infection (PANDAS) and include:

• Abrupt-onset obsessive-compulsive disorder (OCD)
• Hyperactivity/attention-deficit disorder (ADHD)
• Autism
• Tic disorders

The precise nature of the connection between the disorders is not yet understood.

How Is Sydenham Chorea Prevented?

Prevention of Sydenham chorea requires the prevention and treatment of the bacterial infections that cause it. SC is rare in North America and Europe because of the widespread use of antibiotics to treat bacterial infections. Lack of antibiotic treatment and unsanitary conditions make the disorder more common in some parts of the developing world.

Sydenham Chorea Caregiver Tips

• Seek medical advice as soon as you see symptoms of Sydenham chorea or bacterial infection. Although SC itself is often not a long-term problem, the symptoms of the disorder might indicate an underlying problem that could have a serious impact on your child’s health.
• Be aware of the potential complications of SC. Be sure to follow your doctor’s advice and continue treatment with antibiotics as directed. Severe complications of strep infections and recurrence of SC may be avoided if you take precautions.
• Learn about the disorder. The onset of Sydenham chorea can cause confusion and anxiety, especially when you don’t understand what your child is going through. The International Parkinson and Movement Disorder Society maintains a database of articles and studies to help you learn about SC, other types of chorea, and other movement disorders.

Some people with Sydenham chorea also suffer from other brain and mental health-related issues, a condition called co-morbidity. Here are a few of the disorders commonly associated with SC:

• SC is sometimes associated with obsessive-compulsive disorder (OCD).
• SC is also sometimes associated with tic disorders such as Tourette syndrome.
• People with SC may be at higher risk for attention-deficit/hyperactivity disorder (ADHD) and mood disorders such as depression.

Sydenham Chorea Brain Science

Sydenham chorea affects the basal ganglia, the part of the brain that controls movement. Scientists believe that the features of streptococcal bacteria that trigger an immune system response (called antigens) are similar to antigens on the surface of healthy cells in the basal ganglia.

When antibodies created by the immune system mistake healthy brain cells for bacteria, the antibodies bind to the antigens on the brain cells, which interferes with the cells’ ability to communicate with other cells. The interference causes the movement-related symptoms of SC.

Sydenham Chorea Research

Title:  Brain Imaging of Childhood Onset Psychiatric Disorders, Endocrine Disorders, and Healthy Volunteers

Stage: Recruiting

Contact: Armin Raznahan, MD

National Institute of Mental Health (NIMH)

Bethesda, MD

Unlike X-rays and CT scans, magnetic Resonance Imaging (MRI) does not use radiation to create a picture. MRI use, as the name implies, magnetism to create images with excellent anatomical resolution. Functional MRIs are diagnostic tests that allow doctors to not only view anatomy but physiology and function. It is for these reasons that MRIs are excellent methods for studying the brain.

In this study, researchers will use MRI to assess brain anatomy and function in X and Y chromosome variation, healthy volunteers, and patients with various childhood-onset psychiatric disorders. The disorders include attention deficit disorder, autism, congenital adrenal hyperplasia, childhood-onset schizophrenia, dyslexia, obsessive-compulsive disorder, Sydenham’s chorea, and Tourette’s syndrome.  

Objective: The work is driven by the core hypotheses that many of the most severe neuropsychiatric disorders of childhood-onset are associated with deviations from the path of normal brain development, the neuroanatomical substrates of which can be detected by magnetic resonance imaging. Consequently, the long-term goals of the protocol are to (1) map neuroanatomic and neurophysiological trajectories of brain development in health and illness; and (2) discern influences on those trajectories from demographic (e.g., age and sex), cognitive/behavioral (e.g., IQ), and clinical (e.g., presence/absence of known neurogenetic disorders) factors. Data from the project have resulted in seminal papers on Attention-Deficit/Hyperactivity Disorder, Childhood-Onset Schizophrenia, and typical pediatric brain development. The biological bases of male / female differences are explored via studies of subjects with anomalous sex chromosome numbers (e.g., XO, XXX, XYY, XXYY, XXXXY).

Study population: Our studies include data from typically developing youth and individuals with a range of psychiatric presentations from behaviorally-defined (e.g., Childhood-Onset Schizophrenia, Autism Spectrum Disorder) as well as genetically defined (e.g., Sex Chromosome Aneuploidy) groups. Participants span a wide age range (from 3 years of age upwards).

Title: Neurobiologic, Immunologic, and Rheumatologic Markers in Youth With PANS

Stage: Recruiting

Contact: Leora Cherney, PhD

Shirley Ryan AbilityLab

Chicago, IL

This study investigates the neurologic, immunologic, and rheumatologic markers of Pediatric Acute-Onset Neuropsychiatric Syndrome (PANS). PANS is a condition characterized by the abrupt, dramatic onset of obsessive-compulsive disorder (OCD) and/or eating restriction accompanied by equally abrupt and severe co-morbid neuropsychiatric symptoms, which include anxiety, emotional lability, depression, irritability, aggression, oppositionality, deterioration in school performance, behavioral (developmental) regression, sensory amplification, movement abnormalities, sleep disturbance, and urinary frequency. PANS is thought to be caused by infection, inflammation, or alternate triggers associated with a brain response that leads to these symptoms. The purpose of this study is to examine specific neurologic, immunologic, rheumatologic, and genomic components in children with the acute-onset of psychiatric symptoms. This research may begin to uncover a much larger story of autoimmune processes involved in childhood psychiatric disorders. By better understanding the etiologic components of the psychiatric phenomenon, future treatments may be better targeted to underlying causes.

The investigators will recruit 500 children, 1-18 years old at onset with PANS/PANDAS. They will be treatment-naive and within one month of onset/exacerbation. The 500 children with PANS will be gender- and age-matched to 100 healthy children to allow examination of immunologic, neurologic, genomic, and behavioral differences between these two groups of children.

Title: Pilot Study of Strepic® Device for the Diagnosis of Group A Streptococcal Pharyngitis

Stage: Recruiting

Contact: Gregory Moran, MD

Olive View-UCLA Education & Research Institute

Sylmar, CA

The objective of this pilot study is to acquire images using the Strepic® device, a clinical prototype that has been specifically designed as a viable, low-cost, commercially realizable autofluorescence-based diagnostic test, using (1) fluorescence and (2) white light image data, as well as other clinical data points. By acquiring and analyzing the images of pharyngeal bacterial fluorescence and white light patterns in patients with Group A Streptococcus (GAS)-associated pharyngitis, and comparing them with those observed in non-GAS pharyngitis, it is believed an algorithm can be developed such that the device will improve the ability of clinicians to quickly and accurately identify GAS infections.