title: Analysis of the distribution of bacteria within urinary catheter biofilms using four different molecular techniques.
abstract: BACKGROUND
  Most nosocomial urinary tract infections are associated with the long-term use of urinary catheters. Such urinary catheter-associated infections are caused by bacteria that reside in biofilms. We determined the distribution of fastidious/nonculturable bacteria in biofilm of urinary catheters and evaluated the availability of concurrent applying various molecular techniques.
  
  
  METHODS
  The biofilms were isolated from urinary catheters that had been installed in patients for 3 or 4 weeks and examined by the following 4 different 16S ribosomal RNA (rRNA) analysis techniques: capillary electrophoresis, terminal restriction fragment length polymorphism (T-RFLP), denaturing gradient gel electrophoresis (DGGE), and pyrosequencing.
  
  
  RESULTS
  A total of 329 isolates was identified by capillary electrophoresis. The most common genera were Edwardsiella, Enterobacter, Escherichia, and Pseudomonas. A total of 32 bacterial strains was identified by T-RFLP. Escherichia, Pseudomonas, Enterobacter, Moraxella, Proteus, Serratia, and Yersinia were the most represented genera. Similarly, Escherichia, Pseudomonas, and Enterobacter were the most prevalent according to DGGE. Burkholderia, Corynebacterium, Achromobacter, Alcaligenes, Citrobacter, Stenotrophomonas, and Streptococcus were also detected. Escherichia and Pseudomonas were abundantly detected by pyrosequencing. Enterobacter, Bacteroides, Klebsiella, Corynebacterium were also seen.
  
  
  CONCLUSIONS
  These 4 techniques detected different kinds of bacteria, suggesting that the simultaneous application of multiple techniques is necessary to accurately detect fastidious/nonculturable bacteria. Because bacterial growth within urinary catheter biofilms may be associated with urinary tract infections, further comprehensive studies are required.
authors.affiliation: Department of Urology, St Vincent's Hospital, The Catholic University of Korea, College of Medicine, Suwon, Republic of Korea.
authors.forename: Hyun-Sop
authors.initials: HS
authors.lastname: Choe
authors.forename: Su-Wan
authors.initials: SW
authors.lastname: Son
authors.forename: Hyun-Ah
authors.initials: HA
authors.lastname: Choi
authors.forename: Hyun-Jung
authors.initials: HJ
authors.lastname: Kim
authors.forename: Sun-Gook
authors.initials: SG
authors.lastname: Ahn
authors.forename: Jun-Ho
authors.initials: JH
authors.lastname: Bang
authors.forename: Seung-Ju
authors.initials: SJ
authors.lastname: Lee
authors.forename: Ji-Youl
authors.initials: JY
authors.lastname: Lee
authors.forename: Yong-Hyun
authors.initials: YH
authors.lastname: Cho
authors.forename: Sang-Seob
authors.initials: SS
authors.lastname: Lee
mesh_terms: D001419:Bacteria / Q000145:classification* / Q000302:isolation & purification*; D018407:Bacterial Physiological Phenomena; D001431:Bacteriological Techniques / Q000379:methods; D018441:Biofilms; D058448:Biota; D006801:Humans; D008297:Male; D025202:Molecular Diagnostic Techniques / Q000379:methods; D062885:Urinary Catheters / Q000382:microbiology*