title: Nosocomial outbreak of VIM-1-producing Klebsiella pneumoniae isolates of multilocus sequence type 15: molecular basis, clinical risk factors, and outcome.
abstract: We study the epidemiology, molecular basis, clinical risk factors, and outcome involved in the clonal dissemination of VIM-1-producing Klebsiella pneumoniae isolates in the hospital setting. All patients infected/colonized by carbapenem-nonsusceptible K. pneumoniae (CNSKP) in 2009 were included. Molecular epidemiology was studied by pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). Antibiotic resistance genes were analyzed by PCR and sequencing. Plasmids were studied by PFGE with S1 nuclease digestion and for incompatibility group by a PCR-based replicon typing scheme. Risk factors associated with CNSKP colonization/infection were assessed by an observational case-control study. All 55 patients studied were infected (n = 28) or colonized (n = 27) by VIM-1-producing K. pneumoniae. All but one acquired isolates of a single clone (PFGE cluster 1 [C1], sequence type 15 [ST15]), while another clone (PFGE C2, ST340) was detected in four patients. C1 isolates also produced the new extended-spectrum β-lactamase SHV-134. bla(VIM-1) was carried in a class 1 integron and an untypeable plasmid of ∼50 bp. The number of days that the patient received mechanical ventilation, the use of parenteral nutrition, previous treatment with linezolid, and treatment with extended-spectrum cephalosporins for more than 7 days were detected to be independent risk factors for CNSKP acquisition. The VIM-1-producing K. pneumoniae ST15 clone has a high capacity to spread among intensive care unit patients with severe underlying conditions. A high rate of associated mortality and great difficulty in controlling the spread of this clone, without permanent behavioral changes in the personnel, were observed.
authors: Servicio de Microbiología, Hospital Universitario Puerta de Hierro Majadahonda, Madrid, Spain.
authors: Isabel
authors: I
authors: Sánchez-Romero
authors: Angel
authors: A
authors: Asensio
authors: Jesús
authors: J
authors: Oteo
authors: María
authors: M
authors: Muñoz-Algarra
authors: Beatriz
authors: B
authors: Isidoro
authors: Ana
authors: A
authors: Vindel
authors: José
authors: J
authors: Alvarez-Avello
authors: Bárbara
authors: B
authors: Balandín-Moreno
authors: Oscar
authors: O
authors: Cuevas
authors: Sara
authors: S
authors: Fernández-Romero
authors: Luisa
authors: L
authors: Azañedo
authors: David
authors: D
authors: Sáez
authors: José
authors: J
authors: Campos
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000008:administration & dosage*; D015780:Carbapenems / Q000008:administration & dosage*; D016022:Case-Control Studies; D003428:Cross Infection / Q000188:drug therapy* / Q000382:microbiology / Q000401:mortality / Q000635:transmission; D016172:DNA Fingerprinting; D004269:DNA, Bacterial / Q000032:analysis / Q000096:biosynthesis; D004196:Disease Outbreaks; D024901:Drug Resistance, Multiple, Bacterial; D016521:Electrophoresis, Gel, Pulsed-Field; D005260:Female; D006761:Hospitals; D006801:Humans; D007710:Klebsiella Infections / Q000188:drug therapy* / Q000382:microbiology / Q000401:mortality / Q000635:transmission; D007711:Klebsiella pneumoniae / Q000187:drug effects / Q000235:genetics* / Q000302:isolation & purification; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D058885:Multilocus Sequence Typing; D012307:Risk Factors; D013030:Spain / Q000453:epidemiology; D015996:Survival Rate; D016896:Treatment Outcome; D001618:beta-Lactamases / Q000096:biosynthesis
chemical_list: D000900:Anti-Bacterial Agents; D015780:Carbapenems; D004269:DNA, Bacterial; C417264:VIM-1 metallo-beta-lactamase; D001618:beta-Lactamases