title: Similar frequencies of Pseudomonas aeruginosa isolates producing KPC and VIM carbapenemases in diverse genetic clones at tertiary-care hospitals in Medellín, Colombia.
abstract: Carbapenem-resistant Pseudomonas aeruginosa has become a serious health threat worldwide due to the limited options available for its treatment. Understanding its epidemiology contributes to the control of antibiotic resistance. The aim of this study was to describe the clinical and molecular characteristics of infections caused by carbapenem-resistant P. aeruginosa isolates in five tertiary-care hospitals in Medellín, Colombia. A cross-sectional study was conducted in five tertiary-care hospitals from June 2012 to March 2014. All hospitalized patients infected by carbapenem-resistant P. aeruginosa were included. Clinical information was obtained from medical records. Molecular analyses included PCR for detection of bla(VIM), bla(IMP), bla(NDM), bla(OXA-48), and bla(KPC) genes plus pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST) for molecular typing. A total of 235 patients were enrolled: 91.1% of them were adults (n = 214), 88.1% (n = 207) had prior antibiotic use, and 14.9% (n = 35) had urinary tract infections. The bla(VIM-2) and bla(KPC-2) genes were detected in 13.6% (n = 32) and 11.5% (n = 27), respectively, of all isolates. Two isolates harbored both genes simultaneously. For KPC-producing isolates, PFGE revealed closely related strains within each hospital, and sequence types (STs) ST362 and ST235 and two new STs were found by MLST. With PFGE, VIM-producing isolates appeared highly diverse, and MLST revealed ST111 in four hospitals and five new STs. These results show that KPC-producing P. aeruginosa is currently disseminating rapidly and occurring at a frequency similar to that of VIM-producing P. aeruginosa isolates (approximately 1:1 ratio) in Medellín, Colombia. Diverse genetic backgrounds among resistant strains suggest an excessive antibiotic pressure resulting in the selection of resistant strains.
authors.affiliation: Línea de Epidemiología Molecular Bacteriana, Grupo de Microbiología Molecular, Universidad de Antioquia, Medellín, Colombia Grupo de Microbiología Básica y Aplicada, Universidad de Antioquia, Medellín, Colombia.
authors.forename: Johanna M
authors.initials: JM
authors.lastname: Vanegas
authors.affiliation: Línea de Epidemiología Molecular Bacteriana, Grupo de Microbiología Molecular, Universidad de Antioquia, Medellín, Colombia Grupo de Microbiología Básica y Aplicada, Universidad de Antioquia, Medellín, Colombia.
authors.forename: Astrid V
authors.initials: AV
authors.lastname: Cienfuegos
authors.affiliation: Línea de Epidemiología Molecular Bacteriana, Grupo de Microbiología Molecular, Universidad de Antioquia, Medellín, Colombia Grupo de Microbiología Básica y Aplicada, Universidad de Antioquia, Medellín, Colombia.
authors.forename: Ana M
authors.initials: AM
authors.lastname: Ocampo
authors.affiliation: Grupo de Microbiología Básica y Aplicada, Universidad de Antioquia, Medellín, Colombia.
authors.forename: Lucelly
authors.initials: L
authors.lastname: López
authors.affiliation: Grupo de Microbiología Básica y Aplicada, Universidad de Antioquia, Medellín, Colombia.
authors.forename: Helena
authors.initials: H
authors.lastname: del Corral
authors.affiliation: Clínica CardioVID, Medellín, Colombia.
authors.forename: Gustavo
authors.initials: G
authors.lastname: Roncancio
authors.affiliation: IPS Universitaria Clínica León XIII, Medellín, Colombia.
authors.forename: Patricia
authors.initials: P
authors.lastname: Sierra
authors.affiliation: Hospital Universitario San Vicente Fundación, Medellín, Colombia.
authors.forename: Lina
authors.initials: L
authors.lastname: Echeverri-Toro
authors.affiliation: Hospital Universitario San Vicente Fundación, Medellín, Colombia.
authors.forename: Sigifredo
authors.initials: S
authors.lastname: Ospina
authors.affiliation: Clínica El Rosario, Medellín, Colombia.
authors.forename: Natalia
authors.initials: N
authors.lastname: Maldonado
authors.affiliation: Clínica El Rosario, Medellín, Colombia.
authors.forename: Carlos
authors.initials: C
authors.lastname: Robledo
authors.affiliation: Hospital Pablo Tobón Uribe, Medellín, Colombia.
authors.forename: Andrea
authors.initials: A
authors.lastname: Restrepo
authors.affiliation: Línea de Epidemiología Molecular Bacteriana, Grupo de Microbiología Molecular, Universidad de Antioquia, Medellín, Colombia Grupo de Microbiología Básica y Aplicada, Universidad de Antioquia, Medellín, Colombia nataliajiudea@gmail.com.
authors.forename: J Natalia
authors.initials: JN
authors.lastname: Jiménez
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D002648:Child; D016000:Cluster Analysis; D003105:Colombia / Q000453:epidemiology; D003428:Cross Infection / Q000453:epidemiology* / Q000382:microbiology* / Q000473:pathology / Q000635:transmission; D003430:Cross-Sectional Studies; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D016521:Electrophoresis, Gel, Pulsed-Field; D005260:Female; D005838:Genotype; D006801:Humans; D008297:Male; D008875:Middle Aged; D017720:Molecular Epidemiology; D058885:Multilocus Sequence Typing; D016133:Polymerase Chain Reaction; D011552:Pseudomonas Infections / Q000453:epidemiology* / Q000382:microbiology* / Q000473:pathology / Q000635:transmission; D011550:Pseudomonas aeruginosa / Q000145:classification / Q000201:enzymology* / Q000235:genetics / Q000302:isolation & purification; D062606:Tertiary Care Centers; D055815:Young Adult; D001618:beta-Lactamases / Q000235:genetics / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; D004269:DNA, Bacterial; D001618:beta-Lactamases; C063912:carbapenemase