Chorea, Sydenham

• Characterized by an acute onset of choreiform movements, variable degrees of psychological disturbance, rheumatic endocarditis, and arthritis

• Although the disorder follows infections with group A β-hemolytic streptococci, the interval between infection and chorea may be greatly prolonged

• Disease is self-limited; may last from a few weeks up to 18 months

• Relapse may occur with nonspecific stress or illness—or with breakthrough streptococcal infections (if penicillin prophylaxis is not done)

Clinical Findings

• Rapid involuntary discoordinated movements of the limbs and face are hallmarks

• Other symptoms and signs include

  • Emotional lability

  • Waxing and waning ("milkmaid's") grip

  • Darting tongue

  • Spooning" of the extended hands and their tendency to pronate

  • Knee jerks slow to return to their prestimulus position ("hung up" knee jerk)

• Hemichorea occurs in 20% of patients

Diagnosis

• Anemia, leukocytosis, and an increased erythrocyte sedimentation rate and C-reactive protein may be present

• Antistreptolysin O or anti-DNase titer (or both) are usually elevated

• Throat culture is sometimes positive for group A β-hemolytic streptococci

• ECG and echocardiography are often essential to detect cardiac involvement

• If antinuclear antibodies (ANA) are present, chorea may be secondary to lupus

• Similarly, antiphospholipid antibody may be elevated in autoimmune-related chorea

• Testing to exclude other causes may include

  • Thyroid screening tests

  • Serum calcium for hypocalcemia

  • Immunologic and virologic tests for (rare) HIV, parvovirus B19, and Epstein-Barr virus infection

• Brain MRI should be obtained in all children to rule out basal ganglia structural abnormalities, inflammation, and tumor

Treatment

• No specific treatment

• Prednisone (high-dose intravenously or orally 0.5–2 mg/kg/d in divided doses); in severe cases, IVIg has been successful

• Anticonvulsant sodium valproate (50–60 mg/kg/d in divided doses) and levetiracetam (20–80 mg/kg/d divided into twice a day dosing) is effective in reducing chorea symptoms

• Dopaminergic blockers such as haloperidol (0.5 mg/d to 3–6 mg/d) and pimozide (2–10 mg/d) are rarely used because of other effective medications and possible parkinsonian side effects such as rigidity and masked facies, and tardive dyskinesia

• Emotional lability and depression sometimes warrant administration of antidepressants

• All patients should be given antistreptococcal rheumatic fever prophylaxis with either monthly benzylpenicillin injections or oral penicillin VK 250 mg twice a day