title: Outcomes and genetic relatedness of carbapenem-resistant enterobacteriaceae at Detroit medical center.
abstract: BACKGROUND
  Carbapenem-resistant Enterobacteriaceae (CRE) are rapidly emerging in hospitals in the United States and are posing a significant threat. To better understand the transmission dynamics and the acquisition of resistant strains, a thorough analysis of epidemiologic and molecular characteristics was performed.
  
  
  METHODS
  CRE isolated at Detroit Medical Center were analyzed from September 2008 to September 2009. bla(KPC) genes were investigated by polymerase chain reaction (PCR), and repetitive extragenic palindromic PCR (rep-PCR) was used to determine genetic similarity among strains. Epidemiologic and outcomes analyses were performed.
  
  
  RESULTS
  Ninety-two unique patient CRE isolates were recovered. Sixty-eight strains (74%) were Klebsiella pneumoniae, 7 were Klebsiella oxytoca, 15 were Enterobacter species, and 2 were Escherichia coli. Fifteen isolates (16%) were resistant to colistin, 14 (16%) were resistant to tigecycline, and 2 were resistant to all antimicrobials tested. The mean ± standard deviation age of patients was 63 ± 2 years. Sixty patients (68%) were admitted to the hospital from long-term care facilities. Only 70% of patients received effective antimicrobial therapy when infection was suspected, with a mean time to appropriate therapy of 120 ± 23 hours following sample culturing. The mean length of hospitalization after sample culturing was 18.6 ± 2.5 days. Of 57 inpatients, 18 (32%) died in the hospital. Independent predictors for mortality were intensive care unit stay (odds ratio [OR], 15.8; P = .003) and co-colonization with CRE and either Acinetobacter baumannii or Pseudomonas aeruginosa (OR, 17.2; P = .006). Among K. pneumoniae CRE, rep-PCR revealed 2 genetically related strains that comprised 70% and 20% of isolates, respectively.
  
  
  CONCLUSIONS
  In this large U.S. cohort of patients with CRE infection, which reflects the modern continuum of medical care, co-colonization with CRE and A. baumannii or P. aeruginosa was associated with increased mortality. Two predominant clones of K. pneumoniae accounted for the majority of cases of CRE infection.
authors.affiliation: Wayne State University, Detroit, MI, USA. drormc@hotmail.com
authors.forename: Dror
authors.initials: D
authors.lastname: Marchaim
authors.forename: Teena
authors.initials: T
authors.lastname: Chopra
authors.forename: Federico
authors.initials: F
authors.lastname: Perez
authors.forename: Kayoko
authors.initials: K
authors.lastname: Hayakawa
authors.forename: Paul R
authors.initials: PR
authors.lastname: Lephart
authors.forename: Suchitha
authors.initials: S
authors.lastname: Bheemreddy
authors.forename: Christopher
authors.initials: C
authors.lastname: Blunden
authors.forename: Andrea M
authors.initials: AM
authors.lastname: Hujer
authors.forename: Susan
authors.initials: S
authors.lastname: Rudin
authors.forename: Maryann
authors.initials: M
authors.lastname: Shango
authors.forename: Michelle
authors.initials: M
authors.lastname: Campbell
authors.forename: Jastin
authors.initials: J
authors.lastname: Varkey
authors.forename: Jessica
authors.initials: J
authors.lastname: Slim
authors.forename: Farah
authors.initials: F
authors.lastname: Ahmad
authors.forename: Diixa
authors.initials: D
authors.lastname: Patel
authors.forename: Ting-Yi
authors.initials: TY
authors.lastname: Chen
authors.forename: Jason M
authors.initials: JM
authors.lastname: Pogue
authors.forename: Hossein
authors.initials: H
authors.lastname: Salimnia
authors.forename: Sorabh
authors.initials: S
authors.lastname: Dhar
authors.forename: Robert A
authors.initials: RA
authors.lastname: Bonomo
authors.forename: Keith S
authors.initials: KS
authors.lastname: Kaye
mesh_terms: D000046:Academic Medical Centers; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D015780:Carbapenems / Q000494:pharmacology*; D002648:Child; D002675:Child, Preschool; D003091:Colistin / Q000494:pharmacology; D004197:Disease Reservoirs / Q000382:microbiology; D024901:Drug Resistance, Multiple, Bacterial; D004755:Enterobacteriaceae / Q000187:drug effects* / Q000201:enzymology / Q000235:genetics; D004756:Enterobacteriaceae Infections / Q000188:drug therapy / Q000453:epidemiology*; D005260:Female; D005838:Genotype; D017052:Hospital Mortality; D006801:Humans; D007223:Infant; D007902:Length of Stay; D008297:Male; D008824:Michigan / Q000453:epidemiology; D008875:Middle Aged; D008911:Minocycline / Q000031:analogs & derivatives / Q000494:pharmacology; D009735:Nursing Homes; D012189:Retrospective Studies; D000078304:Tigecycline; D016896:Treatment Outcome; D055815:Young Adult; D018440:beta-Lactam Resistance
chemical_list: D000900:Anti-Bacterial Agents; D015780:Carbapenems; D000078304:Tigecycline; D008911:Minocycline; D003091:Colistin