Neurobiologia da síndrome de Tourette: a hipótese auto-imune pós-estreptocócica Neurobiology of Tourette's syndrome: the autoimmune post-streptococcal hypothesis

Background: Tourette’s syndrome (TS) is characterized by the presence of motor tics and at least one phonic tic. Some clinical similarities with Sydenham’s chorea (SC) lead to the hypothesis of a new group of disorders associated with an autoimmune process due to a streptococcal infection (PANDAS). Objective: To review the literature in search of evidence on the existence of post-streptococcal autoimmune mechanisms involved with the etiopathogenesis of TS. Methods: A systematic review with the terms “Tourette”, “tic”, “PANDAS”, “antibodies”, “streptococcal” and “rheumatic” was carried on using the MedLine. Results: The search found 238 articles. Fifty and three articles were selected which also had their references reviewed. The results of studies that investigated autoimmune aspects of TS, including anti-streptococcal and anti-basal ganglia anti-bodies, and immune-based therapy, were presented and discussed. Discussion: The evidences to date are not satisfactory regarding a post-streptococcal auto-immune process in ST. The improvement on investigative methods and sample selection might contribute to this question.