Changes in the gut microbiota in autism in children: pathogenetic significance and ways of correction

Abstract

A systematic review of data on the interrelationship between the gut microbiota and autism spectrum disorder (ASD) in children is presented. The search was conducted in Pubmed, Google Academic, and Web of Science databases for the keywords: autism, autism spectrum disorder, gut microbiota. Articles published between January 2000 and August 2023 were reviewed, and preference was given to data obtained in recent years. It was found that 40% of ASD children have various forms and severity of manifestations of gastrointestinal dysfunction (constipation, diarrhea, chronic abdominal pain, etc.), which accompany psychopathological symptoms and correlate with the severity of ASD. Disorders of the intestinal microbiota are detected in more than 80% of cases of ASD in children. At the same time, it was found that representatives of the fila Firmicutes, Bacteroidetes and Proteobacteria are the most common in the intestinal microbiota in ASD children, although their qualitative and quantitative ratios in ASD differ. In patients with ASD, a decrease in the content of representatives of the phylum Firmicutes and a relatively high prevalence of Bacteroidetes producing short-chain fatty acids were revealed, due to this, they can influence the central nervous system and behaviour in autism. Differences in the biodiversity of the intestinal microbiota in ASD are determined by heterogeneity of demographic and geographical characteristics, differences in diet, concomitant forms of pathology, severity of behavioural and gastrointestinal symptoms, different methods of analysis and treatment. Modification of the intestinal microbiome by fecal microbiota transplantation is potentially the most promising way to improve gastrointestinal and behavioural symptoms in ASD children.