title: Outbreak caused by a multi-resistant Klebsiella pneumoniae strain of new sequence type ST341 carrying new genetic environments of aac(6')-Ib-cr and qnrS1 genes in a neonatal intensive care unit in Spain.
abstract: An outbreak due to a Klebsiella pneumoniae clone occurred in a neonatal intensive care unit of a Spanish Hospital in which three newborns were infected (all with gestational age ≤29 weeks; two of them died) and seven were colonized (gestational age >32 weeks; none died). One K. pneumoniae strain per patient was further characterized. The 10 strains showed an indistinguishable pulsed-field-gel-electrophoresis pattern, were typed in the phylogenetic group KpI and were ascribed into a new sequence type registered as ST341. All 10 strains presented the same multiple-antibiotic-resistant phenotype, showed extended-spectrum-beta-lactamase production, and harbored the bla(CTX-M-15), bla(SHV-11), bla(OXA-1,)aac(6')-Ib-cr, qnrS1, aac(3)-II, aph(3')-Ia and aadA5 resistance genes. No class 1 or class 2 integrons were detected. The bla(CTX-M-15) gene presented the following genetic environment: ISEcp1-bla(CTX-M-15)-orf477. These strains contained two copies of the aac(6')-Ib-cr gene included in the following new genetic environments: aac(3)-II-IS26-aac(6')-Ib-cr-bla(OXA-1) and aac(3)-II-IS26-ΔcatB3-bla(OXA-1)-aac(6')-Ib-cr (registered at GenBank with accession numbers GQ438247 and GQ438248, respectively). The genetic environment of the qnrS1 gene (IS26-ΔISEcl2-qnrS1) (GenBank accession number GQ438249) was also not described previously. The aac(6')-Ib-cr, qnrS1, bla(CTX-M-15), aac(3)-II, and bla(OXA-1) genes, located in a plasmid of 33.5 kb, could be transferred to Escherichia coli by transformation.
authors.affiliation: Area de Bioquímica y Biología Molecular, Departamento de Agricultura y Alimentación, Universidad de La Rioja, Logroño, Spain.
authors.forename: Elena
authors.initials: E
authors.lastname: Ruiz
authors.forename: Beatriz
authors.initials: B
authors.lastname: Rojo-Bezares
authors.forename: Yolanda
authors.initials: Y
authors.lastname: Sáenz
authors.forename: Inés
authors.initials: I
authors.lastname: Olarte
authors.forename: Inés
authors.initials: I
authors.lastname: Esteban
authors.forename: Rosa
authors.initials: R
authors.lastname: Rocha-Gracia
authors.forename: Myriam
authors.initials: M
authors.lastname: Zarazaga
authors.forename: Carmen
authors.initials: C
authors.lastname: Torres
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D015373:Bacterial Typing Techniques; D002353:Carrier State / Q000453:epidemiology / Q000382:microbiology; D016000:Cluster Analysis; D003428:Cross Infection / Q000453:epidemiology / Q000382:microbiology; D016172:DNA Fingerprinting; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004196:Disease Outbreaks; D024901:Drug Resistance, Multiple, Bacterial; D016521:Electrophoresis, Gel, Pulsed-Field; D005260:Female; D005798:Genes, Bacterial / Q000235:genetics; D005838:Genotype; D006801:Humans; D007231:Infant, Newborn; D007363:Intensive Care Units, Neonatal; D007710:Klebsiella Infections / Q000453:epidemiology* / Q000382:microbiology; D007711:Klebsiella pneumoniae / Q000145:classification* / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification; D008297:Male; D008969:Molecular Sequence Data; D017422:Sequence Analysis, DNA; D013030:Spain / Q000453:epidemiology
chemical_list: D000900:Anti-Bacterial Agents; D004269:DNA, Bacterial