Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by social and behavioral impairments. Recent studies have suggested that gut microbiota play a critical role in ASD pathogenesis. Herein, we investigated the fecal microflora of Korean ASD children to determine gut microbiota profiles associated with ASD. Specifically, fecal samples were obtained from 54 children with ASD and 38 age-matched children exhibiting typical development. Systematic bioinformatic analysis revealed that the composition of gut microbiota differed between ASD and typically developing children (TDC). Moreover, the total amounts of short-chain fatty acids, metabolites produced by bacteria, were increased in ASD children. At the phylum level, we found a significant decrease in the relative Bacteroidetes abundance of the ASD group, whereas Actinobacteria abundance was significantly increased. Furthermore, we found significantly lower Bacteroides levels and higher Bifidobacterium levels in the ASD group than in the TDC group at the genus level. Functional analysis of the microbiota in ASD children predicted that several pathways, including genetic information processing and amino acid metabolism, can be associated with ASD pathogenesis. Although more research is needed to determine whether the differences between ASD and TDC are actually related to ASD pathogenesis, these results provide further evidence of altered gut microbiota in children with ASD, possibly providing new perspectives on the diagnosis and therapeutic approaches for ASD patients.

Because modifying risk factors of suicide attempt is important for preventing completed suicide, clinicians should carefully evaluate and monitor the risk factors of suicide attempt.

The aim of this study was to investigate differences in language ability and emotional-behavioral problems according to the severity of social communication impairments (SCI) and restricted and repetitive behaviors (RRB) in children with autism spectrum disorders (ASD). Materials and Methods: We grouped 113 children with ASD aged 3-12 years according to the severity of SCI and RRB, and investigated language differences and emotional-behavioral problems among the severity groups. If differences in language abilities between the groups were observed, they were further subdivided to examine possible predictors of both receptive and expressive language abilities. Results: In cluster analyses using subdomains of the Autism Diagnostic Interview-revised, severe SCI individuals showed lower language ability than their milder counterparts, while RRB showed no differences. Receptive and expressive language in the severe SCI group was negatively predicted by social communication and social motivation, respectively. The severe RRB group showed significantly higher levels of anxiety/distress, somatic complaints, thought problems, attention problems, and aggressive behavior, while the severe SCI group was reported to be more withdrawn. Conclusion: The results of this study suggest that the severity of SCI greatly affects language ability. In children with severe SCI, social communication and social motivation negatively predicted receptive language and expressive language, respectively. Children with severe RRB may have more emotional-behavioral problems that require active intervention.