Summary about Disease
Sydenham's Chorea (SC), also known as St. Vitus' dance, is a neurological disorder characterized by rapid, jerky, and involuntary movements affecting primarily the face, hands, and feet. It is a major manifestation of acute rheumatic fever (ARF), a delayed autoimmune reaction to a Group A streptococcal infection (like strep throat or scarlet fever). SC typically affects children and adolescents, primarily between the ages of 5 and 15. While it can be a self-limiting condition, it can cause significant disruption in daily life and, in rare cases, can lead to long-term neurological complications.
Symptoms
Chorea: The hallmark symptom is involuntary, rapid, jerky, and non-rhythmic movements. These movements can affect the face (grimacing, tongue darting), arms, legs, and trunk.
Hypotonia: Muscle weakness or floppiness can occur, particularly in the early stages.
Emotional Lability: Sudden and unpredictable mood swings, irritability, and crying spells.
Motor Impersistence: Difficulty maintaining a sustained motor act (e.g., keeping the tongue out, maintaining a grip).
Speech Difficulties: Slurred or hesitant speech.
Writing Difficulties: Deterioration in handwriting.
Facial Grimacing Involuntary contortions of facial muscles.
Milkmaid's Grip: Intermittent squeezing and releasing of the hand when shaking hands.
Prone to dropping things.
Causes
Sydenham's Chorea is caused by an autoimmune response to a Group A streptococcal infection, such as strep throat or scarlet fever. The antibodies produced by the body to fight the streptococcal infection mistakenly attack the basal ganglia, a part of the brain responsible for motor control and coordination. This autoimmune attack disrupts the normal function of the basal ganglia, leading to the characteristic choreiform movements. Genetic predisposition may also play a role.
Medicine Used
Penicillin: To eradicate any remaining streptococcal infection and prevent future ARF attacks. Long-term prophylactic antibiotics (e.g., monthly penicillin injections) are often prescribed.
Haloperidol or Risperidone: These are neuroleptic medications used to control the choreiform movements. They work by blocking dopamine receptors in the brain.
Valproic Acid or Carbamazepine: These are anticonvulsant medications that can also help to reduce the severity of the chorea.
Corticosteroids or Intravenous Immunoglobulin (IVIG): Used in severe cases to suppress the autoimmune response.
Supportive Care: Occupational therapy and physical therapy may be beneficial to improve motor skills and coordination.
Is Communicable
Sydenham's Chorea itself is not communicable. It is an autoimmune response, not an infectious disease. However, the underlying Group A streptococcal infection (e.g., strep throat) that triggers the rheumatic fever and subsequently Sydenham's Chorea is communicable.
Precautions
Prompt Treatment of Strep Throat: Ensuring prompt and complete treatment of strep throat with antibiotics is crucial to prevent acute rheumatic fever and, therefore, Sydenham's Chorea.
Prophylactic Antibiotics: Individuals who have had ARF or SC are typically prescribed long-term prophylactic antibiotics (usually penicillin) to prevent recurrent streptococcal infections and subsequent ARF attacks.
Monitor for Symptoms: Careful monitoring of children and adolescents for signs and symptoms of strep throat (sore throat, fever, headache, rash) is important.
Maintain Good Hygiene: Practicing good hygiene, such as frequent handwashing, can help prevent the spread of streptococcal infections.
Cardiac Monitoring: Since ARF can affect the heart, regular cardiac evaluations are important, especially in individuals with a history of ARF or SC.
How long does an outbreak last?
The duration of Sydenham's Chorea is variable. It typically lasts for several weeks to months, with an average duration of 2 to 6 months. In some cases, symptoms can persist for up to two years or longer. Relapses can occur, although they are less common with proper prophylactic antibiotic treatment to prevent recurrent streptococcal infections.
How is it diagnosed?
The diagnosis of Sydenham's Chorea is based on a combination of clinical findings, medical history, and laboratory tests:
Clinical Evaluation: A thorough neurological examination to assess for choreiform movements, hypotonia, and other neurological signs. Detailed history of the patient’s symptoms.
Medical History: Inquiring about a recent history of strep throat or scarlet fever.
Laboratory Tests:
Throat Culture or Rapid Strep Test: To detect the presence of Group A streptococcus.
Anti-Streptolysin O (ASO) Titer: To measure antibodies against streptolysin O, a substance produced by Group A streptococcus. Elevated ASO titers indicate a recent streptococcal infection.
Anti-DNase B Titer: Another antibody test that can help confirm a recent streptococcal infection, especially if the ASO titer is not elevated.
Erythrocyte Sedimentation Rate (ESR) and C-Reactive Protein (CRP): These are markers of inflammation in the body and are often elevated in ARF.
Echocardiogram: To evaluate for carditis (inflammation of the heart), another manifestation of ARF.
Ruling Out Other Conditions: It's important to rule out other conditions that can cause chorea, such as Wilson's disease, Huntington's disease, and drug-induced chorea.
Timeline of Symptoms
The timeline of symptoms in Sydenham's Chorea can vary, but a typical progression is as follows:
2-6 months after Streptococcal Infection: There is usually a latent period between the initial strep infection and the onset of neurological symptoms.
Initial Phase: Subtle behavioral changes, such as irritability, emotional lability, and difficulty concentrating, may be noticed.
Gradual Onset of Chorea: The choreiform movements typically begin gradually, often affecting the face, hands, and feet.
Progression of Symptoms: The chorea becomes more pronounced and generalized over time. Hypotonia (muscle weakness) may also develop.
Peak Severity: Symptoms usually reach their peak severity within a few weeks to months.
Gradual Improvement: Over several weeks to months, the chorea gradually improves. Some symptoms, such as emotional lability, may persist for a longer period.
Resolution: In most cases, Sydenham's Chorea resolves completely, although some individuals may experience mild residual neurological deficits.
Important Considerations
Early Diagnosis and Treatment: Early diagnosis and treatment of Sydenham's Chorea are important to minimize the severity and duration of symptoms and to prevent potential complications.
Cardiac Involvement: ARF can affect the heart (carditis), leading to long-term heart damage (rheumatic heart disease). Regular cardiac monitoring is crucial.
Prophylactic Antibiotics: Adherence to long-term prophylactic antibiotic treatment is essential to prevent recurrent streptococcal infections and ARF attacks.
Psychological Support: The emotional and behavioral changes associated with Sydenham's Chorea can be distressing for the affected individual and their family. Psychological support and counseling may be beneficial.
Differential Diagnosis: It is important to consider other conditions that can cause chorea, such as Wilson's disease, Huntington's disease, and drug-induced chorea, to ensure accurate diagnosis and management.
Pregnancy: Chorea gravidarum, a form of chorea that can occur during pregnancy, is thought to be related to Sydenham's Chorea in some cases. Women with a history of SC should be closely monitored during pregnancy.
Long-term Follow-up: Regular follow-up with a neurologist and cardiologist is important to monitor for potential complications and to ensure optimal management of the condition.