[Involvement of intestinal dysbiosis in the etiopathogenesis and treatment of autism spectrum disorder: a bibliographic review].

INTRODUCTION Autism spectrum disorder is a neurodevelopmental disorder with phenotypic heterogeneity and variable symptomatic course of partly unknown etiology. The prevalence of gastrointestinal disorders in autism leads to investigate the role that intestinal microbiota may have as a causal factor and to propose specific therapeutic interventions. The role of microbiota in brain development and function, demonstrated in animal models, justifies its investigation in this neuropsychiatric disorder. OBJECTIVE The aim was to investigate the relationship between altered microbiota composition and autism spectrum disorder, and to assess the therapeutic role of prebiotics, probiotics and fecal transplantation in this neurodevelopmental disorder. DEVELOPMENT A literature review was conducted in PubMed, Cochrane Library and Google Scholar to select relevant articles related to the topic that were published between January 2012 and April 2020. Thirty-five relevant articles were selected. In 23 of them, significant differences were found in the composition and diversity of the microbiota in children with ASD, as well as in the biomolecules involved in certain metabolic pathways. The other 12 investigations reported gastrointestinal and behavioral improvements after therapeutic intervention. CONCLUSIONS It is reasonable to state that there is enough evidence to support the existence of a relationship between intestinal microbiota and autism spectrum disorders. This fact should be explored in depth to assess the etiopathogenic burden of dysbiosis and the possible therapeutic tools.