title: Outbreaks of colistin-resistant and colistin-susceptible KPC-producing Klebsiella pneumoniae in a Brazilian intensive care unit.
abstract: BACKGROUND
  Carbapenem-resistant Enterobacteriaceae (CRE), especially those that produce Klebsiella pneumoniae carbapenemase (KPC) and are associated with colistin resistance, pose a severe health threat due to the limited treatment options.
  
  
  OBJECTIVE
  To describe two outbreaks of KPC-producing K. pneumoniae in an adult intensive care unit (AICU) in Brazil. In May 2015, 14 patients had colistin-susceptible KPC-producing strains (ColS-KPC), and in July 2015, nine patients had colistin-resistant KPC-producing strains (ColR-KPC).
  
  
  METHODS
  Between September 2014 and August 2015, we performed surveillance at a university hospital and all CRE were tested for blaKPCgenes. Clonality was investigated by pulsed-field gel electrophoresis. Resistance to colistin was confirmed by broth microdilution method. Consumption of carbapenems and colistin was expressed as defined daily doses.
  
  
  RESULTS
  In all, 111 patients with CRE were identified during the surveillance period; K. pneumoniae was the major isolate (77.13%). The two outbreaks were identified when infection rates (KPC per 1000 patient-days) exceeded the background level. Rates of carbapenem and colistin consumption were high. Control measures (bedside alcohol gel, contact precautions, regular rectal swabs) did not curtail the outbreaks. Mortality rates were 42.9% and 44.4% for ColS-KPC- and ColR-KPC-infected patients, respectively. After the death of four infected patients with ColR-KPC, the unit was closed to new admissions.
  
  
  CONCLUSIONS
  Our experience demonstrates the serious risks presented by KPC, and especially ColR-KPC, in Brazilian AICUs. Selective pressure from excessive antibiotic use and transmission on healthcare workers' hands were likely the major factors in transmission.
authors.affiliation: Laboratory of Microbiology, Biomedical Science Institute, Federal University of Uberlândia, Uberlândia, MG, Brazil. Electronic address: iara_rossi@hotmail.com.
authors.forename: I
authors.initials: I
authors.lastname: Rossi Gonçalves
authors.affiliation: Laboratory of Microbiology, Biomedical Science Institute, Federal University of Uberlândia, Uberlândia, MG, Brazil.
authors.forename: M L
authors.initials: ML
authors.lastname: Ferreira
authors.affiliation: Laboratory of Microbiology, Biomedical Science Institute, Federal University of Uberlândia, Uberlândia, MG, Brazil.
authors.forename: B F
authors.initials: BF
authors.lastname: Araujo
authors.affiliation: Laboratory of Microbiology, Biomedical Science Institute, Federal University of Uberlândia, Uberlândia, MG, Brazil.
authors.forename: P A
authors.initials: PA
authors.lastname: Campos
authors.affiliation: Laboratory of Microbiology, Biomedical Science Institute, Federal University of Uberlândia, Uberlândia, MG, Brazil.
authors.forename: S
authors.initials: S
authors.lastname: Royer
authors.affiliation: Faculty of Medicine, Federal University of Uberlândia, Uberlândia, MG, Brazil.
authors.forename: D W F
authors.initials: DW
authors.lastname: Batistão
authors.affiliation: Laboratory of Microbiology, Biomedical Science Institute, Federal University of Uberlândia, Uberlândia, MG, Brazil.
authors.forename: L P
authors.initials: LP
authors.lastname: Souza
authors.affiliation: Laboratory of Microbiology, Biomedical Science Institute, Federal University of Uberlândia, Uberlândia, MG, Brazil.
authors.forename: C S
authors.initials: CS
authors.lastname: Brito
authors.affiliation: Hospital Infection Control Committee, Hospital das Clínicas, Federal University of Uberlândia, Uberlândia, MG, Brazil.
authors.forename: J E
authors.initials: JE
authors.lastname: Urzedo
authors.affiliation: Laboratory of Microbiology, Biomedical Science Institute, Federal University of Uberlândia, Uberlândia, MG, Brazil.
authors.forename: P P
authors.initials: PP
authors.lastname: Gontijo-Filho
authors.affiliation: Laboratory of Microbiology, Biomedical Science Institute, Federal University of Uberlândia, Uberlândia, MG, Brazil; Hospital Infection Control Committee, Hospital das Clínicas, Federal University of Uberlândia, Uberlândia, MG, Brazil.
authors.forename: R M
authors.initials: RM
authors.lastname: Ribas
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001426:Bacterial Proteins / Q000378:metabolism*; D001938:Brazil / Q000453:epidemiology; D003091:Colistin / Q000494:pharmacology*; D004196:Disease Outbreaks; D016521:Electrophoresis, Gel, Pulsed-Field; D005260:Female; D006785:Hospitals, University; D006801:Humans; D007223:Infant; D007362:Intensive Care Units; D007710:Klebsiella Infections / Q000453:epidemiology* / Q000382:microbiology; D007711:Klebsiella pneumoniae / Q000145:classification / Q000187:drug effects* / Q000201:enzymology / Q000302:isolation & purification; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D058889:Molecular Typing; D055815:Young Adult; D001618:beta-Lactamases / Q000378:metabolism*
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D001618:beta-Lactamases; C063912:carbapenemase; D003091:Colistin
keywords: Antimicrobial resistance; Carbapenem; Colistin; Intensive care unit; Klebsiella pneumoniae; Outbreak