Composition of the intestinal microbiota in extended-spectrum β-lactamase-producing Enterobacteriaceae carriers and non-carriers in Thailand.

There is increasing recognition that the intestinal microbiota govern human well-being and prevent diseases. Intestinal colonization by antibiotic-resistant pathogens, however, can lead to the spread of resistance as well as serious infections. Extended-spectrum β-lactamase-producing Enterobacteriaceae (ESBL-E) represent particularly dangerous pathogens, which are known to asymptomatically colonize the intestinal tract in the community. Here, we performed a 16S rRNA metagenomics sequence analysis to analyse differences in the microbiota composition between ESBL-E carriers and non-carriers in Thailand, where ESBL-E carriage rates are notoriously high. The most notable difference detected was that the phylum Bacteroidetes, and in particular, the species Bacteroides uniformis, were significantly more abundant in ESBL-E non-carriers than carriers. The Shannon diversity index in non-carriers (5.10 ± 0.69) was also lower than that in ESBL-E carriers (5.39 ± 0.48) without statistical significance (P=0.13). The overall beta diversity difference of the intestinal microbiota of ESBL-E carriers as compared to non-carriers was statistically significant (Adonis on weighted unifrac: R2=0.14, P=0.005). Furthermore, ESBL-E carriage was significantly lower in farmers than in those with other occupations. Our findings suggest that a dynamic interaction exists between microbiota diversity and ESBL-E carriage, which is possibly driven by dietary composition and may be exploited using probiotic approaches to control the spread of ESBL-E.