Gut microbiota compositions in the carriers and noncarriers of third-generation cephalosporin–resistant Escherichia coli: A study among children in southern Taiwan

Antimicrobial resistance, particularly in third-generation cephalosporin–resistant (3GC-R) (), poses major global health challenges and has various clinical implications. Researchers have explored the relationship between extended-spectrum β-lactamase–producing and gut microbiota composition, which influence host health and disease susceptibility, in adults. In this study, we analyzed gut microbiota composition in Taiwanese children by the colonization status of 3GC-R . This cross-sectional study included children (age, 0–6 years) from Kaohsiung, Taiwan. Fecal samples were subjected to microbiological and gut microbiome (full-length 16S rRNA sequencing) analyses. The antimicrobial susceptibility of colonies isolated from the samples was tested. Furthermore, gut microbiota compositions and diversity indices were compared between 3GC-R carriers and noncarriers. Approximately 46% of all children aged <6 years carried 3GC-R . The abundances of , , and (genus level) were higher in carriers than in noncarriers. By contrast, the abundances of (family level) and (genus level) were higher in noncarriers than in carriers. No significant between-group difference was observed in alpha diversity. However, a significant between-group difference was noted in beta diversity (unweighted UniFrac analysis). This is the first study that investigated differences in the gut microbiota between healthy 3GC-R carriers and noncarriers in children, suggesting potential mechanisms involving altered utilization of short-chain fatty acids and elevated succinate levels contributing to increased colonization of 3GC-R . The other taxa identified in this study may contribute to colonization resistance in the pediatric population.