title: Uropathogen interaction with the surface of urological stents using different surface properties.
abstract: OBJECTIVE
  Ureteral stents commonly become infected or encrusted. Various coatings have been developed to decrease bacterial adherence. To our knowledge there has been no in vitro testing of coating with heparin to date. We determined the effects of heparin coating on bacterial adherence of common uropathogens and physical stent properties.
  
  
  METHODS
  Heparin coated Radiance ureteral stents (Cook) and noncoated Endo-Sof control stents were tested against triclosan eluting Triumph(R) stents and noneluting Polaris control stents for adherence of Escherichia coli, Klebsiella pneumoniae, Enterococcus faecalis, Staphylococcus aureus and Pseudomonas aeruginosa for 7 days. Adherent bacteria were determined and biofilms were visualized using fluorescent dyes. Radial, tensile and coil strength of the Radiance and Polaris stents was compared to determine the effect of heparin coating on physical stent characteristics.
  
  
  RESULTS
  Heparin coating did not decrease bacterial adhesion compared to its control. E. coli adhesion was limited by all stents tested. The Polaris stent showed significantly greater resistance to bacterial adherence for Klebsiella, Pseudomonas and Enterococcus than the Endo-Sof and Radiance stents but was more susceptible to S. aureus adherence. The Triumph stent resisted all bacteria except Pseudomonas and Enterococcus. Mature biofilms were observed on all stents with lower viability on the Triumph stent. Radiance stents showed higher tensile and lower compression strength than its control.
  
  
  CONCLUSIONS
  Heparin coating does not decrease bacterial adherence to ureteral stents. Drug eluting antimicrobials have an inhibitory effect on bacterial adherence and the Polaris stent showed the least bacterial adherence of the nondrug eluting ureteral stents tested.
authors.affiliation: Stone Centre at Vancouver General Hospital, Department of Urologic Sciences, University of British Columbia, Vancouver, Canada.
authors.forename: Dirk
authors.initials: D
authors.lastname: Lange
authors.forename: Chelsea N
authors.initials: CN
authors.lastname: Elwood
authors.forename: Kenny
authors.initials: K
authors.lastname: Choi
authors.forename: Kari
authors.initials: K
authors.lastname: Hendlin
authors.forename: Manoj
authors.initials: M
authors.lastname: Monga
authors.forename: Ben H
authors.initials: BH
authors.lastname: Chew
mesh_terms: D001422:Bacterial Adhesion / Q000187:drug effects*; D001672:Biocompatible Materials; D018441:Biofilms; D001696:Biomechanical Phenomena; D020099:Coated Materials, Biocompatible; D006493:Heparin; D008422:Materials Testing; D015607:Stents / Q000382:microbiology*; D013499:Surface Properties; D014546:Urinary Catheterization / Q000295:instrumentation*
chemical_list: D001672:Biocompatible Materials; D020099:Coated Materials, Biocompatible; D006493:Heparin