title: Fecal carriage of MDROs in a population of Lebanese elderly: Dynamics and impact on bacterial fitness.
abstract: Muti-Drug Resistant Organisms (MDROs) are problematic all over the world, especially in Lebanon. High fecal carriage rates of MDR Enterobacteriaceae were reported from Lebanese nursing homes. Some studies show that MDROs have a fitness cost as compared to sensitive isolates. In this study, the competitive growth of MDR Escherichia coli obtained from fecal samples from elderly is assessed. Fecal swabs from ten elderly patients from a Lebanese nursing home were obtained between June and December, 2015. Isolates were identified by API 20E and antimicrobial susceptibilities were determined. Production of ESBL (extended spectrum β lactamase), MBL (metallo β lactamse), AmpC and KPC (Klebsiella pneumonia carbapenemase) was detected phenotypically by the use of EDTA, PBA, cloxacillin, and DDSTs. In-vitro competition assays were performed using E. coli isolates with different combinations of bacterial resistance. A total of 117 isolates was obtained with 71.8% E. coli, 7.7% of which were ESBL and 5.1% AmpC producers. Sensitive E. coli isolates out-competed all other isolates when in competition, followed sequentially by ESBL, AmpC, and OXA-48 (oxacillin) producers. This study shows an advantage of sensitive E. coli strains obtained from fecal samples to out-compete resistant strains in specific in-vitro conditions. This ability could be exploited in the elimination of MDR organisms from the gut flora, after further investigation.
authors.affiliation: Faculty of Medicine, Clinical Microbiology Lab, University of Balamand, Lebanon.
authors.forename: Caren
authors.initials: C
authors.lastname: Challita
authors.affiliation: Faculty of Veterinary, Department of Animal Health, Universidad Complutense de Madrid, Madrid, Spain.
authors.forename: Elias
authors.initials: E
authors.lastname: Dahdouh
authors.affiliation: Faculty of Medicine, Clinical Microbiology Lab, University of Balamand, Lebanon.
authors.forename: Michel
authors.initials: M
authors.lastname: Attieh
authors.affiliation: Faculty of Medicine, Clinical Microbiology Lab, University of Balamand, Lebanon.
authors.forename: Iman
authors.initials: I
authors.lastname: Dandachi
authors.affiliation: Faculty of Medicine, Clinical Microbiology Lab, University of Balamand, Lebanon.
authors.forename: Elio
authors.initials: E
authors.lastname: Ragheb
authors.affiliation: Faculty of Medicine, Clinical Microbiology Lab, University of Balamand, Lebanon.
authors.forename: Roy
authors.initials: R
authors.lastname: Taoutel
authors.affiliation: Faculty of Medicine, Clinical Microbiology Lab, University of Balamand, Lebanon.
authors.forename: Carl
authors.initials: C
authors.lastname: Tanba
authors.affiliation: Faculty of Medicine, Clinical Microbiology Lab, University of Balamand, Lebanon. Electronic address: ziad.daoud@balamand.edu.lb.
authors.forename: Ziad
authors.initials: Z
authors.lastname: Daoud
mesh_terms: D000368:Aged; D003430:Cross-Sectional Studies; D024901:Drug Resistance, Multiple, Bacterial; D004755:Enterobacteriaceae / Q000187:drug effects* / Q000201:enzymology / Q000254:growth & development / Q000302:isolation & purification*; D004926:Escherichia coli / Q000187:drug effects / Q000201:enzymology / Q000302:isolation & purification; D005243:Feces / Q000382:microbiology*; D006801:Humans; D007861:Lebanon; D009735:Nursing Homes; D010641:Phenotype; D001618:beta-Lactamases / Q000378:metabolism
chemical_list: D001618:beta-Lactamases
keywords: Fecal carriage; Fitness cost; Multi-Drug Resistant Organisms; Nursing homes