Revisiting an immunoneuropsychiatry classic: Sydenham's chorea

Sydenham chorea (SC) is the major neurologic manifestation of rheumatic fever. It is defined by characteristic involuntary movements and frequently associated with neuropsychiatric symptoms that may develop weeks or months following a Group A beta hemolytic streptococcal (GAS) infection.

The authors searched PubMed database for recent original studies and systematic reviews on SC pathogenesis, clinical spectrum and therapeutic approaches.

Compelling evidence supports that autoantibodies targeting neuronal antigens underly the pathogenesis of SC. In the basal ganglia, autoantibodies react, among other epitopes, with dopamine type 2 (D2) receptors. The resulting dopaminergic signaling dysfunction leads to SC-related motor and neuropsychiatric symptoms. A key gap in the antibody-mediated hypothesis of SC lays on the limited understanding on how peripherally generated autoantibodies reach the basal ganglia. D2 antagonists and valproic acid are the main symptomatic therapeutic strategies for SC. The use of corticosteroids can accelerate the resolution of motor symptoms, and must be considered in severe cases, including chorea paralytica. Plasmapheresis and immunoglobulin have been considered investigational for SC.