title: Multiresistant extended-spectrum β-lactamase-producing Enterobacteriaceae from humans, companion animals and horses in central Hesse, Germany.
abstract: BACKGROUND
  Multiresistant Gram-negative bacteria producing extended-spectrum β-lactamases (ESBLs) are an emerging problem in human and veterinary medicine. This study focused on comparative molecular characterization of β-lactamase and ESBL-producing Enterobacteriaceae isolates from central Hesse in Germany. Isolates originated from humans, companion animals (dogs and cats) and horses.
  
  
  RESULTS
  In this study 153 (83.6%) of the human isolates (n = 183) and 163 (91.6%) of the animal isolates (n = 178) were confirmed as ESBL producers by PCR and subsequent sequencing of the PCR amplicons. Predominant ESBL subtypes in human and animal samples were CTX-M-15 (49.3%) and CTX-M-1 (25.8%) respectively. Subtype blaCTX-M-2 was found almost exclusively in equine and was absent from human isolates. The carbapenemase OXA-48 was detected in 19 ertapenem-resistant companion animal isolates in this study. The Plasmid-encoded quinolone resistance (PMQR) gene aac('6)-Ib-cr was the most frequently detected antibiotic- resistance gene present in 27.9% of the human and 36.9% of the animal ciprofloxacin-resistant isolates. Combinations of two or up to six different resistance genes (penicillinases, ESBLs and PMQR) were detected in 70% of all isolates investigated. The most frequent species in this study was Escherichia coli (74%), followed by Klebsiella pneumoniae (17.5%), and Enterobacter cloacae (4.2%). Investigation of Escherichia coli phylogenetic groups revealed underrepresentation of group B2 within the animal isolates.
  
  
  CONCLUSIONS
  Isolates from human, companion animals and horses shared several characteristics regarding presence of ESBL, PMQR and combination of different resistance genes. The results indicate active transmission and dissemination of multi-resistant Enterobacteriaceae among human and animal populations.
authors.forename: Judith
authors.initials: J
authors.lastname: Schmiedel
authors.forename: Linda
authors.initials: L
authors.lastname: Falgenhauer
authors.forename: Eugen
authors.initials: E
authors.lastname: Domann
authors.forename: Rolf
authors.initials: R
authors.lastname: Bauerfeind
authors.forename: Ellen
authors.initials: E
authors.lastname: Prenger-Berninghoff
authors.affiliation: Institute of Medical Microbiology, Justus Liebig University Giessen and German Center for Infection Research (DZIF), Partner site Giessen-Marburg-Langen, Schubertstrasse 81, 35392 Giessen, Germany. Can.imirzalioglu@mikrobio.med.uni-giessen.de.
authors.forename: Can
authors.initials: C
authors.lastname: Imirzalioglu
authors.forename: Trinad
authors.initials: T
authors.lastname: Chakraborty
mesh_terms: D000818:Animals; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D024901:Drug Resistance, Multiple, Bacterial; D004755:Enterobacteriaceae / Q000187:drug effects* / Q000201:enzymology* / Q000302:isolation & purification; D005838:Genotype; D005858:Germany; D006736:Horses; D006801:Humans; D057805:Pets; D016133:Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D001618:beta-Lactamases / Q000235:genetics*
chemical_list: D004269:DNA, Bacterial; D001618:beta-Lactamases