Gluten Ataxia and Post-Streptococcal Central Nervous System Syndromes: Emerging Immune-mediated Disorders of the Central Nervous System?

There is an "emerging concept" that central nervous system dysfunction can be caused by an aberrant immune response triggered by exogenous antigens such as the food allergen gluten or streptococcal infection. The hypothesis of a gluten sensitive ataxia remains unproven, but is worthy of consideration. The data in support of this hypothesis require critical review before any treatment recommendations can be formulated. The idea that anti-gliadin antibody seropositivity per se justifies the term "gluten sensitivity" is important because it offers potential therapeutic possibilities, including simple exclusion diets, for patients with anti-gliadin antibody-associated ataxia. Post-streptococcal basal ganglia dysfunction has various manifestations, all of which fall into a relatively well-defined symptom complex or syndrome. Anti-basal ganglia antibodies that are associated with serologic evidence of recent streptococcal infection are a potential diagnostic marker for this group of disorders, which includes Sydenham's chorea (SC) as the prototype. More recently subjects with pediatric autoimmune neuropsychiatric disorders associated with streptococcal infection, Tourette's syndrome, obsessive-compulsive disorder and other movement disorders have been described in association with anti-basal ganglia antibodies. The apparent overlap between the clinical phenotype of SC, pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections, Tourette's syndrome, and obsessive-compulsive disorder suggests that they may represent one disease entity. The current working hypothesis is that antibodies induced in response to streptococcal infection cross-react with antigenic determinants in the basal ganglia resulting in basal ganglia dysfunction. Although the experimental evidence is incomplete, there is sufficient evidence to support immune-mediated basal ganglia dysfunction as an emerging clinical entity. This has important implications for the diagnosis and treatment of subjects with these disorders. The latter includes the judicious use of antibiotic prophylaxis and immunomodulatory therapies. Apart from the diagnosis and management of SC, no consensus exists regarding the diagnosis and management of the other clinical entities within this group of disorders.