title: "Silent" dissemination of Klebsiella pneumoniae isolates bearing K. pneumoniae carbapenemase in a long-term care facility for children and young adults in Northeast Ohio.
abstract: BACKGROUND
  Klebsiella pneumoniae isolates harboring the K. pneumoniae carbapenemase gene (bla(KPC)) are creating a significant healthcare threat in both acute and long-term care facilities (LTCFs). As part of a study conducted in 2004 to determine the risk of stool colonization with extended-spectrum cephalosporin-resistant gram-negative bacteria, 12 isolates of K. pneumoniae that exhibited nonsusceptibility to extended-spectrum cephalosporins were detected. All were gastrointestinal carriage isolates that were not associated with infection.
  
  
  METHODS
  Reassessment of the carbapenem minimum inhibitory concentrations using revised 2011 Clinical Laboratory Standards Institute breakpoints uncovered carbapenem resistance. To further investigate, a DNA microarray assay, PCR-sequencing of bla genes, immunoblotting, repetitive-sequence-based PCR (rep-PCR) and multilocus sequence typing (MLST) were performed.
  
  
  RESULTS
  The DNA microarray detected bla(KPC) in all 12 isolates, and bla(KPC-3) was identified by PCR amplification and sequencing of the amplicon. In addition, a bla(SHV-11) gene was detected in all isolates. Immunoblotting revealed "low-level" production of the K. pneumoniae carbapenemase, and rep-PCR indicated that all bla(KPC-3)-positive K. pneumoniae strains were genetically related (≥98% similar). According to MLST, all isolates belonged to sequence type 36. This sequence type has not been previously linked with bla(KPC) carriage. Plasmids from 3 representative isolates readily transferred the bla(KPC-3) to Escherichia coli J-53 recipients.
  
  
  CONCLUSIONS
  Our findings reveal the "silent" dissemination of bla(KPC-3) as part of Tn4401b on a mobile plasmid in Northeast Ohio nearly a decade ago and establish the first report, to our knowledge, of K. pneumoniae containing bla(KPC-3) in an LTCF caring for neurologically impaired children and young adults.
authors.affiliation: Department of Medicine, Jacobi Medical Center, Albert Einstein College of Medicine, Bronx, New York, USA. robert.bonomo@va.gov
authors.forename: Roberto A
authors.initials: RA
authors.lastname: Viau
authors.forename: Andrea M
authors.initials: AM
authors.lastname: Hujer
authors.forename: Steven H
authors.initials: SH
authors.lastname: Marshall
authors.forename: Federico
authors.initials: F
authors.lastname: Perez
authors.forename: Kristine M
authors.initials: KM
authors.lastname: Hujer
authors.forename: David F
authors.initials: DF
authors.lastname: Briceño
authors.forename: Michael
authors.initials: M
authors.lastname: Dul
authors.forename: Michael R
authors.initials: MR
authors.lastname: Jacobs
authors.forename: Richard
authors.initials: R
authors.lastname: Grossberg
authors.forename: Philip
authors.initials: P
authors.lastname: Toltzis
authors.forename: Robert A
authors.initials: RA
authors.lastname: Bonomo
mesh_terms: D000293:Adolescent; D000328:Adult; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001426:Bacterial Proteins / Q000235:genetics*; D015780:Carbapenems / Q000378:metabolism / Q000494:pharmacology; D002648:Child; D002675:Child, Preschool; D004269:DNA, Bacterial / Q000235:genetics; D024881:Drug Resistance, Bacterial; D016521:Electrophoresis, Gel, Pulsed-Field; D004926:Escherichia coli / Q000187:drug effects / Q000235:genetics / Q000302:isolation & purification; D005260:Female; D006801:Humans; D007710:Klebsiella Infections / Q000453:epidemiology / Q000382:microbiology* / Q000635:transmission; D007711:Klebsiella pneumoniae / Q000187:drug effects / Q000201:enzymology* / Q000235:genetics*; D008134:Long-Term Care; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D058885:Multilocus Sequence Typing; D009820:Ohio / Q000453:epidemiology; D020411:Oligonucleotide Array Sequence Analysis; D010957:Plasmids / Q000235:genetics; D016133:Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D055815:Young Adult; D001618:beta-Lactamases / Q000235:genetics*
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D015780:Carbapenems; D004269:DNA, Bacterial; D001618:beta-Lactamases; C063912:carbapenemase