Sydenham’s Chorea

Authors:

Ayesha Hameed MBBS,

Tasneem Kousar MBBS,

Adeel Memon MD

Introduction

• A rare hyperkinetic autoimmune movement disorder affecting children

• Phenomenology: brief, involuntary, jerky, uncontrollable movements of the face, arms, legs, and trunk muscles

Affected Population

• More prevalent in girls more than boys

• More common between the ages of 5 and 15

• It affects all races and ethnicities

• 25% of patients with rheumatic fever develop Sydenham chorea

Clinical Features

• Acute to subacute onset following streptococcal infection

• In addition to chorea, symptoms also include behavioral changes, including anxiety, obsessive-compulsive disorder, and attention

• In rare cases, affected children may become bedridden due to severe muscle weakness, and this condition is called paralytic chorea

• The symptoms may vary and are presented in Table 1

Signs & Symptoms

• Choreic movements

• Muscle weakness

• Behavioural disturbances such as inattention/obsessions/compulsion/anxiety/ labile mood

• Facial grimacing

• Restlessness

• Slurred speech

• Diminished muscle tone

Causes

• The choreiform movement is caused by the autoimmune reaction to the streptococcal infection

• The antibodies produced by the immune system persist and attack certain cells in the joints, kidneys, heart and in the brain specifically basal ganglia which plays a key role in controlling motor movements

Differential Diagnosis

• Autoimmune or paraneoplastic: Anti-Hu(ANNA-1); Anti-NMDA; anti-CRMP5; anti-IgLON5; anti-LGI-1

• Polycythemia vera

• Endocrinological disorders-hyperparathyroidism, pseudohypoparathyroidism, both hypo or hyperthyroidism, and nonketotic hyperglycemia

• Neurodegenerative disorders: Huntington's disease, Dentatorubropallidolysian atrophy, C9orf72 disease, and Spinocerebellar ataxias

Diagnosis

• Clinically - acute onset of choreic movements associated with behavioral changes

• A confirmation of streptococcal infection via swab

• High blood titres of streptococcal antibodies such as ASO is also useful in making the diagnosis

• Brain imaging is usually normal in Sydenham Chorea

• Often during the acute phase SPECT shows striatal hyperperfusion which evolves to hypoperfusion during the illness

Treatment

Symptomatic Medications

• Bed rest
• During the period of active movements is recommended for the mildest form

• When chorea is disabling and interferes with rest
• Low Dose Anticonvulsants
• Valporate (20mg/kg/day)
• Carbamezatpine (15 mg/kg/day)
• Neuroleptics
• Symptomatic treatment with neuroleptics can be considered while treating the underlying illness
• Of note neuroleptics should be used for patients who fail valproic acid or carbamazepine therapy due to negative side effects
• The most common neuroleptics used are pimozide and haloperidol
• Atypical antipsychotics, such as risperidone and olanzapine can also be considered

Acute and Prophylactic Penicillin Therapy

• Treatment with Penicillin at the time of diagnosis of SC, 10 days
• Prevents additional complications of rheumatic fever

• The WHO recommends Penicillin G (1.2 million units) IM QDaily for 21 Days
• Duration depends upon the severity of carditis

• It is recommended to stop the prophylaxis after 5 years or age 18 (whichever is longer) in patients with no carditis

• Patients with mild carditis should continue for 10 years or age 21

• Patients with moderate to severe carditis should receive lifelong prophylaxis

Immunomodulatory therapy

• Short term immunotherapy such as oral steroids and IV immunoglobulins have been used to treat patients with disabling symptoms and in cases of uncontrolled or persisting chorea,

• The two most common regimens are:
• Oral prednisone (2 mg/kg/day) for ~ 21 - 30 days prolonged taper
• Methylprednisolone (25 mg/kg/day) ~ 21 - 30 days prolonged taper

Prognosis

• Good with complete recovery in most cases

• Duration of symptoms usually vary between 3-6 weeks; some children can have symptoms for several months

• Cardiac complications such as endocarditis may occur in some children

• 1/3rd of patients will experience recurrence of SC, usually after 1 and a half to 2 years after the initial attack

• Researchers have noticed an association between Recurrent SC and Rapid onset of PANDAS
• PANDAS (Pediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcus infection)
• PANDAS is characterized by Obsessive-compulsive disorder, attention deficit/hyperactivity-disorder, tic disorders, and autism

Further Reading

• Ben-Pazi, H., Stoner, J. A., & Cunningham, M. W. (2013). Dopamine receptor autoantibodies correlate with symptoms in Sydenham's chorea. PloS one, 8(9), e73516. https://doi.org/10.1371/journal.pone.0073516

• Sehar, A., Nasir, S., & Seja, A. (2019). Rheumatic Chorea as the First Presenting Sign in a 13-year-old Female Child. Cureus, 11(8), e5447. https://doi.org/10.7759/cureus.5447

• https://bmcinfectdis.biomedcentral.com/articles/10.1186/s12879-021-06005-x

Bibliography

• Dean, S. L., & Singer, H. S. (2017). Treatment of Sydenham's Chorea: A Review of the Current Evidence. Tremor and other hyperkinetic movements (New York, N.Y.), 7, 456. https://doi.org/10.7916/D8W95GJ2

• Sydenham chorea. NORD (National Organization for Rare Disorders). (2020, September 1). https://rarediseases.org/rare-diseases/sydenham-chorea/.

• Sydenham's chorea. Brain Foundation. (n.d.). https://brainfoundation.org.au/disorders/sydenhams-chorea/.

• U.S. Department of Health and Human Services. (n.d.). Sydenham chorea information page. National Institute of Neurological Disorders and Stroke. https://www.ninds.nih.gov/Disorders/All-Disorders/Sydenham-Chorea-Information-Page.