title: In vivo horizontal dissemination of the blaKPC-2gene carried on diverse genetic platforms among clinical isolates of Enterobacteriaceae.
abstract: This study investigated the molecular characteristics of six blaKPC-positive Enterobacteriaceae recovered from three patients in Argentina. Antimicrobial susceptibility testing was performed following Clinical and Laboratory Standards Institute (CLSI) 2014 recommendations. Molecular characterisation of the isolates was performed by biparental conjugation, PCR, sequencing, S1 nuclease restriction, and Southern blot hybridisation with a blaKPCprobe using standard protocols and conditions. The isolates studied were as follows. Case 1: Escherichia coli (ECO-P1) and Klebsiella pneumoniae (KPN-P1) isolated from a rectal swab harboured blaKPC-2in transposon Tn4401a on non-typeable and non-conjugative plasmids. Case 2: Enterobacter cloacae (ECL-P2) and K. pneumoniae (KPN-P2) were isolated from two blood cultures. blaKPC-2was found in a novel genetic variant of ISKpn8-blaKPC-2-ISKpn6-like on conjugative plasmids of IncL/M type. Case 3, Citrobacter freundii (CFR-P3) and Klebsiella oxytoca (KOX-P3) were isolated from skin and skin-structure infection. The blaKPCgene was detected on ISKpn8-ΔblaTEM-blaKPC-2-ISKpn6-like located on an IncA/C conjugative plasmid. CFR-P3 and KOX-P3 harboured blaPER-2in addition to the blaKPCgene. In conclusion, we document the horizontal dissemination of blaKPC-2from diverse Enterobacteriaceae clinical isolates with different genetic backgrounds. This is the first report of E. coli harbouring blaKPCassociated with Tn4401a in Argentina.
authors.affiliation: Servicio Antimicrobianos, National Reference Laboratory in Antimicrobial Resistance, Instituto Nacional de Enfermedades Infecciosas ANLIS 'Dr Carlos G. Malbrán', Buenos Aires, Argentina.
authors.forename: M S
authors.initials: MS
authors.lastname: Anchordoqui
authors.affiliation: Servicio Antimicrobianos, National Reference Laboratory in Antimicrobial Resistance, Instituto Nacional de Enfermedades Infecciosas ANLIS 'Dr Carlos G. Malbrán', Buenos Aires, Argentina; Research Career, CONICET (Consejo Nacional de Investigaciones Científicas y Tecnológicas).
authors.forename: D
authors.initials: D
authors.lastname: De Belder
authors.affiliation: Servicio Antimicrobianos, National Reference Laboratory in Antimicrobial Resistance, Instituto Nacional de Enfermedades Infecciosas ANLIS 'Dr Carlos G. Malbrán', Buenos Aires, Argentina.
authors.forename: C
authors.initials: C
authors.lastname: Lucero
authors.affiliation: Servicio Antimicrobianos, National Reference Laboratory in Antimicrobial Resistance, Instituto Nacional de Enfermedades Infecciosas ANLIS 'Dr Carlos G. Malbrán', Buenos Aires, Argentina.
authors.forename: M
authors.initials: M
authors.lastname: Rapoport
authors.affiliation: Servicio Antimicrobianos, National Reference Laboratory in Antimicrobial Resistance, Instituto Nacional de Enfermedades Infecciosas ANLIS 'Dr Carlos G. Malbrán', Buenos Aires, Argentina; Research Career, CONICET (Consejo Nacional de Investigaciones Científicas y Tecnológicas).
authors.forename: D
authors.initials: D
authors.lastname: Faccone
authors.affiliation: Clínica y Maternidad Suizo Argentina, Buenos Aires, Argentina.
authors.forename: A
authors.initials: A
authors.lastname: Rodriguez
authors.affiliation: Sanatorio Mitre, Buenos Aires, Argentina.
authors.forename: A
authors.initials: A
authors.lastname: Di Martino
authors.affiliation: Servicio Antimicrobianos, National Reference Laboratory in Antimicrobial Resistance, Instituto Nacional de Enfermedades Infecciosas ANLIS 'Dr Carlos G. Malbrán', Buenos Aires, Argentina.
authors.forename: F
authors.initials: F
authors.lastname: Martino
authors.affiliation: Hospital Municipal de Urgencias, Córdoba, Argentina.
authors.forename: I
authors.initials: I
authors.lastname: Herrero
authors.affiliation: Servicio Antimicrobianos, National Reference Laboratory in Antimicrobial Resistance, Instituto Nacional de Enfermedades Infecciosas ANLIS 'Dr Carlos G. Malbrán', Buenos Aires, Argentina.
authors.forename: F
authors.initials: F
authors.lastname: Pasteran
authors.affiliation: Servicio Antimicrobianos, National Reference Laboratory in Antimicrobial Resistance, Instituto Nacional de Enfermedades Infecciosas ANLIS 'Dr Carlos G. Malbrán', Buenos Aires, Argentina.
authors.forename: A
authors.initials: A
authors.lastname: Corso
authors.affiliation: Servicio Antimicrobianos, National Reference Laboratory in Antimicrobial Resistance, Instituto Nacional de Enfermedades Infecciosas ANLIS 'Dr Carlos G. Malbrán', Buenos Aires, Argentina; Research Career, CONICET (Consejo Nacional de Investigaciones Científicas y Tecnológicas). Electronic address: sgomez@anlis.gov.ar.
authors.forename: S A
authors.initials: SA
authors.lastname: Gomez
keywords: Enterobacteriaceae; Horizontal dissemination; KPC-2; Tn4401a