title: Detection of class 1 and 2 integrons, extended-spectrum β-lactamases and qnr alleles in enterobacterial isolates from the digestive tract of Intensive Care Unit inpatients.
abstract: In this study, we searched for extended-spectrum β-lactamases (ESBLs), class 1 and 2 integrons, and qnrA, qnrB and qnrS genes in 56 oxyimino-cephalosporin and/or ciprofloxacin-resistant enterobacterial isolates obtained from the gastrointestinal tract of patients admitted in an Intensive Care Unit in Uruguay. ESBLs were detected in 11 isolates (6 CTX-M-2, 3 CTX-M-9, 1 CTX-M-15 and 1 PER-2). qnr genes and integrons were detected in 5 and 24 isolates, respectively. Eight different antibiotic resistance gene cassettes were found within six different genetic arrangements. Two types of complex class 1 integrons carrying insertion sequence ISCR1 were found, one showing bla(CTX-M-2)-orf3 and the other qnrA1-ampR. Ten of the thirteen isolates carrying class 2 integrons presented the element IS5 inserted between intI2 and dfrA1, whereas another class 2 integron lacked the internal stop codon usually present in intI2. This is the first report of the occurrence of qnrA, qnrB and bla(CTX-M-9) in Uruguay. Dissemination of the different groups of CTX-M enzymes (i.e. groups 1, 2 and 9) appears to be a recent phenomenon in South America.
authors.affiliation: Departamento de Bacteriología y Virología, Instituto de Higiene, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay.
authors.forename: Inés
authors.initials: I
authors.lastname: Bado
authors.forename: Nicolás F
authors.initials: NF
authors.lastname: Cordeiro
authors.forename: Luciana
authors.initials: L
authors.lastname: Robino
authors.forename: Virginia
authors.initials: V
authors.lastname: García-Fulgueiras
authors.forename: Verónica
authors.initials: V
authors.lastname: Seija
authors.forename: Cristina
authors.initials: C
authors.lastname: Bazet
authors.forename: Gabriel
authors.initials: G
authors.lastname: Gutkind
authors.forename: Juan A
authors.initials: JA
authors.lastname: Ayala
authors.forename: Rafael
authors.initials: R
authors.lastname: Vignoli
mesh_terms: D000483:Alleles; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001426:Bacterial Proteins / Q000235:genetics*; D002511:Cephalosporins / Q000494:pharmacology; D002939:Ciprofloxacin / Q000494:pharmacology; D024881:Drug Resistance, Bacterial; D004755:Enterobacteriaceae / Q000235:genetics* / Q000302:isolation & purification; D041981:Gastrointestinal Tract / Q000382:microbiology*; D006801:Humans; D032023:Integrons; D007362:Intensive Care Units; D014583:Uruguay; D001618:beta-Lactamases / Q000235:genetics*
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D002511:Cephalosporins; D002939:Ciprofloxacin; D001618:beta-Lactamases