10-Fold increase (2006-11) in the rate of healthy subjects with extended-spectrum  -lactamase-producing Escherichia coli faecal carriage in a Parisian check-up centre

• Published in: Journal of antimicrobial chemotherapy 2013-03, Vol.68 (3), p.562-568
• Main Authors: Nicolas-Chanoine, M.-H., Gruson, C., Bialek-Davenet, S., Bertrand, X., Thomas-Jean, F., Bert, F., Moyat, M., Meiller, E., Marcon, E., Danchin, N., Noussair, L., Moreau, R., Leflon-Guibout, V.
• Format: Article
• Language: English
• Subjects: Bacterial infections; beta -Lactamase; Digestive tract; E coli; Enzymes; Escherichia coli; Evolution; Feces; Inventories; Phylogenetics; Phylogeny; Polyclonal antibodies; Risk factors
• ISSN: 0305-7453; 1460-2091
• DOI: 10.1093/jac/dks429

In 2006, 0.6% of healthy subjects living in the Paris area had extended-spectrum β-lactamase (ESBL)-producing Escherichia coli in their gut. To assess the evolution of this rate, a study identical to that of 2006 was conducted in 2011. Healthy adults who visited the IPC check-up centre in February-March 2011 and agreed to participate, provided stools and answered a questionnaire on the visit day. Stools were analysed to detect ESBL producers and to isolate the dominant E. coli population. ESBLs were molecularly characterized. For the subjects harbouring ESBL-producing E. coli, the phylogenetic group and sequence type (ST) were determined for both ESBL-producing and dominant E. coli isolates. PFGE profiles were also determined when two types of isolates had the same ST. Among the 345 subjects included, 21 (6%) had ESBL-producing E. coli faecal carriage. None of the previously published risk factors was identified. CTX-M accounted for 86% and SHV-12 for 14%. Dominant and ESBL-producing E. coli were similarly distributed into phylogenetic groups (A, 52%-48%; B1, 5%; B2, 24%-14%; and D, 19%-33%). Dominant and ESBL-producing E. coli displayed a polyclonal structure (18 STs each). However, ST10 and ST131 were identified in dominant and ESBL-producing E. coli isolates from different subjects. Most (20/21) ESBL producers were subdominant and belonged (16/21) to STs different from that of the corresponding dominant E. coli. The 10-fold increase in the rate of healthy subjects with ESBL-producing E. coli faecal carriage over a 5 year period suggests wide dissemination of these isolates in the Parisian community.