Sydenham Chorea: Symptoms, Types, Causes and Treatment

Sydenham chorea (SC)—sometimes called St. Vitus dance—is a fascinating and complex neuropsychiatric disorder most commonly seen in children and adolescents. Once a frequent diagnosis in the era before antibiotics, this movement disorder is still encountered worldwide, especially in regions where rheumatic fever remains common. Sydenham chorea is not just a movement disorder: it’s a window into the intricate relationship between infections, the immune system, the brain, and behavior. In this comprehensive article, we’ll delve into its symptoms, types, causes, and evidence-based treatments, synthesizing up-to-date research to provide a clear, structured overview.

Symptoms of Sydenham Chorea

Sydenham chorea is renowned for its involuntary, unpredictable movements, but its symptoms span both physical and psychological domains. These can greatly impact daily life and may even precede the motor symptoms, making early recognition essential for effective intervention. Let’s break down the key symptoms below.

Symptom	Description	Frequency/Impact	Sources
Chorea	Rapid, irregular, purposeless movements	Most common, face/extremities	1 4 5
Speech Issues	Dysarthria, slurred speech, difficulty speaking	Frequently observed	1 4 5
Gait Disturbance	Unsteady walking, balance problems	Common	1 5
Psychological	Obsessive-compulsive, emotional lability, anxiety, depression	Up to 82% with psych symptoms	1 3 6

Table 1: Key Symptoms

Motor Symptoms: The Hallmark of Sydenham Chorea

The classic image of Sydenham chorea involves rapid, jerky, and uncoordinated movements affecting the face, limbs, and trunk. These movements are involuntary and unpredictable, often described as "dance-like" or fidgety, and can be mistaken for behavioral issues in children. Additional motor features include:

• Facial grimacing and twitching
• Gait disturbances, leading to unsteady walking, falls, or clumsiness
• Speech difficulties such as slurred speech (dysarthria), and trouble grasping utensils or writing (dysgraphia)
• Milkmaid’s grip: an inability to maintain a steady hand grip, with intermittent squeezing and releasing 1 4 5

Neuropsychiatric and Behavioral Symptoms

Sydenham chorea is as much a psychiatric as a neurological disorder. Many children experience:

• Obsessive-compulsive symptoms (seen in up to 82% of cases), including repetitive thoughts and actions
• Emotional lability: rapid mood changes, irritability, or crying spells
• Motor hyperactivity, distractibility, and regressed behavior
• Anxiety and depression: anxiety disorders and depressive symptoms are reported in the majority of affected children 1 3 6

Importantly, psychological symptoms often precede the onset of visible chorea by days or weeks and wax and wane with motor symptoms 1.

Other Associated Features

• Muscle weakness: may be significant enough to cause difficulty with daily activities
• Speech and swallowing difficulties
• Cardiac involvement: murmurs or evidence of rheumatic carditis in some patients (see Causes section) 4 5

Early recognition of both the physical and psychological symptoms is critical for diagnosis and management.

Types of Sydenham Chorea

Sydenham chorea is not a "one size fits all" disorder. Understanding its various forms helps clinicians tailor management, anticipate complications, and counsel families appropriately.

Type	Key Features	Prevalence/Notes	Sources
Generalized	Movements affect most/all limbs	Most common (~66–67%)	3 7
Hemichorea	One side of body affected	13–34%	3 7 5
Focal/Multifocal	Isolated or several regions	~20% in pregnancy	7
Chorea Gravidarum	Chorea in pregnancy, often recurrence	75% of pregnant SC patients	7

Table 2: Types of Sydenham Chorea

Generalized Sydenham Chorea

This is the most typical form, characterized by involuntary movements involving the face, trunk, and all four limbs. It often results in significant functional impairment, impacting speech, activities of daily living, and school performance 3 7.

Hemichorea

Here, only one side of the body is affected. Hemichorea is more commonly observed in children but can also appear in adults. Its presence should prompt a thorough diagnostic workup to rule out other causes, but in the context of rheumatic fever, it is a recognized presentation 3 5 7.

Focal and Multifocal Chorea

These less common types involve one or several regions of the body (e.g., just one arm and the face). Focal or multifocal presentations are particularly noted in pregnant women with a prior history of SC 7.

Chorea Gravidarum

Pregnancy can unmask or exacerbate Sydenham chorea, leading to the so-called chorea gravidarum. This typically emerges in the first six months of pregnancy and may remit after delivery, although persistent symptoms can last up to a year postpartum. Notably, hormonal changes are believed to trigger recurrence in women with prior SC, and oral contraceptives can also provoke relapse 7.

Special Forms: Chorea Paralytica

A rare, severe variant called chorea paralytica is marked by profound muscle weakness and almost complete loss of voluntary movement. It usually responds to high-dose corticosteroids 8.

Understanding these subtypes is essential for accurate diagnosis and prognosis, particularly in special populations such as pregnant women.

Causes of Sydenham Chorea

The roots of Sydenham chorea lie in a complex interplay of infection, immunity, and neurobiology. Let’s explore what science currently knows.

Cause	Mechanism/Description	Main Evidence	Sources
Post-Streptococcal	Autoimmune response after Group A Streptococcus (GAS) infection	Major cause; rheumatic fever link	2 3 4 6 10
Rheumatic Fever	Manifestation of ARF, often with carditis	Major diagnostic criterion	3 4 5 10
Autoimmunity	Antibodies target basal ganglia, dopamine receptors	Neuropsychiatric symptoms	2 6
Hormonal Factors	Estrogen/progesterone effects in pregnancy	Chorea gravidarum	7

Table 3: Causes of Sydenham Chorea

Post-Streptococcal Autoimmunity

SC most commonly follows an untreated or inadequately treated infection with Group A beta-hemolytic Streptococcus (GAS), the bacteria that also cause strep throat. It is a major manifestation of acute rheumatic fever (ARF), itself a post-infectious, autoimmune complication 3 4 10.

• Latency Period: Symptoms typically appear several weeks to months after the initial infection, reflecting the time needed for the immune response to develop 4 10.
• Diagnostic Clues: Elevated antistreptolysin O (ASO) and anti-DNase B titers, along with evidence of recent strep infection, support the diagnosis 4 5.

Autoimmune Attack on the Basal Ganglia

The immune system, while targeting the strep bacteria, mistakenly attacks the basal ganglia (deep brain structures controlling movement and behavior) due to molecular mimicry.

• Antineuronal Antibodies: Research has identified antibodies directed against neurons of the caudate nucleus and dopamine receptors (D1R and D2R) in affected patients 2 6.
• Dopaminergic Imbalance: An altered balance of dopamine signaling, driven by these antibodies, is thought to underlie both the movement and psychiatric symptoms. The ratio of anti-D2R to anti-D1R antibodies correlates with symptom severity 2.
• Cholinergic-Dopaminergic Imbalance: Disruption in the balance of neurotransmitters, especially dopamine and acetylcholine, is believed to contribute to the involuntary movements 6.

Link to Rheumatic Fever and Cardiac Disease

SC is a major criterion for ARF diagnosis. Many patients will have associated cardiac involvement, such as valvular damage (e.g., mitral regurgitation) 3 4 5 10.

Hormonal and Other Contributing Factors

• Pregnancy: Hormonal changes can unmask or worsen chorea in women with a previous history of SC (chorea gravidarum) 7.
• Genetic Predisposition: While less well-defined, some evidence suggests that genetic factors may influence susceptibility.

Exclusion of Other Causes

MRI and other investigations are used primarily to rule out alternative causes of chorea, as SC itself rarely produces distinctive imaging findings 8.

Treatment of Sydenham Chorea

Managing Sydenham chorea requires a multifaceted approach, targeting both the underlying cause and the diverse range of symptoms. Treatment decisions are often individualized due to the lack of robust, standardized guidelines.

Treatment	Approach/Drugs	Key Considerations	Sources
Antibiotics	Penicillin (acute & prophylactic)	Prevents recurrence/ARF	4 9 13
Symptomatic	Dopamine antagonists (haloperidol), anticonvulsants (valproic acid, carbamazepine)	Controls movements, side effects possible	6 9 12 13
Immunotherapy	Steroids, IVIG, plasma exchange	For severe/refractory cases	11 12 13 14
Supportive Care	Physiotherapy, psychological support	Addresses functional impact	1 3

Table 4: Treatment Options

Antibiotic Therapy: Addressing the Underlying Cause

• Acute Phase: All patients should receive antibiotics (usually penicillin) to eradicate any persisting streptococcal infection 4 9 13.
• Long-Term Prophylaxis: Continued penicillin prophylaxis is essential to prevent recurrence of both rheumatic fever and chorea, and to minimize the risk of cardiac complications 4 13.

Symptomatic Treatment: Managing Movement and Psychiatric Issues

• Dopamine Antagonists: Haloperidol and other antipsychotics help reduce involuntary movements but may have side effects like sedation or extrapyramidal symptoms 6 9 13.
• Anticonvulsants: Drugs such as valproic acid and carbamazepine are also effective in controlling choreiform movements, especially when antipsychotics are not tolerated 6 9 12 13.
• Benzodiazepines: Occasionally used for severe agitation or anxiety.

Note: Symptomatic therapies are often the first-line for mild to moderate cases. However, relapse rates may be higher with symptomatic drugs alone compared to immunotherapy 3.

Immunomodulatory Therapy: For Severe or Refractory Cases

• Corticosteroids: Prednisone and intravenous methylprednisolone can be effective, particularly in patients not responding to symptomatic therapy 11 12. Side effects (e.g., Cushing syndrome) may occur with prolonged use 12.
• Intravenous Immunoglobulin (IVIG): Emerging evidence suggests IVIG can speed recovery and reduce severity, especially in severe cases 11 14.
• Plasma Exchange: Used in select, treatment-resistant cases; some studies show rapid improvement 11.
• Selection of Therapy: No single approach is universally superior; decisions are based on severity, response to initial treatment, and clinician experience 9 13.

Supportive and Psychological Care

• Physical and Occupational Therapy: To help regain motor skills and improve coordination 3.
• Psychological Support: Addressing obsessive-compulsive symptoms, anxiety, and depression is crucial; in some cases, psychiatric medications may be needed 1 3.
• Educational Support: School accommodations may be necessary during periods of significant impairment.

Prognosis and Relapse

• Most patients experience neurological remission within 6 months, but relapses can occur, particularly if antibiotic prophylaxis lapses or symptomatic therapy is used alone 3.
• Neuropsychiatric symptoms may persist beyond motor symptom resolution in a minority 3.

Conclusion

Sydenham chorea is a unique intersection of infection, immunity, neurology, and psychiatry. While the classic image is of a child with dance-like movements, the real story includes profound psychological symptoms, immune-mediated brain dysfunction, and a risk of serious heart disease if not recognized and treated promptly.

Key Points:

• Wide Symptom Spectrum: SC affects movement, mood, and behavior; motor and psychological symptoms can both precede and follow each other 1 3 6.
• Multiple Types Exist: Generalized, hemichorea, and special forms like chorea gravidarum have distinct features and implications 3 7.
• Autoimmune Cause: Triggered by a streptococcal infection, SC is mediated by antibodies that mistakenly target the brain’s movement centers 2 6.
• Treatment is Multifaceted: Antibiotics, symptomatic drugs, and immunotherapy all play a role; treatment is tailored to severity and response 4 9 11 13.
• Prognosis is Generally Good: Most children recover within months, but monitoring for relapse and long-term psychological support are important 3.

Early recognition and comprehensive care are the keys to reducing both the neurological and psychological burden of Sydenham chorea, ensuring the best possible outcome for affected individuals.