title: Inactivation of Bacteria on Explanted Dialysis Catheter Lumens with Fiber Optically Delivered Ultraviolet Light.
abstract: OBJECTIVE
  To evaluate the germicidal effect of fiber optically delivered ultraviolet (UV) light on colonized explanted dialysis catheters.
  
  
  METHODS
  Explanted dialysis catheters were screened for intraluminal colonization by culturing 1 mL of a saline flush. Catheters growing >10 colony-forming units were treated with doses of fiber optically delivered UV light (range, 40-1,300 mJ/cm2). For each UV-treated catheter, an unexposed segment was first cut and set aside as a control sample. A sterile optical fiber was inserted into the catheter hub and advanced to the catheter tip. The fiber was slowly withdrawn at a constant rate while exposing the inner lumen to UV light. A second UV-exposed segment was then removed. The UV-exposed and control segments were split and sonicated to remove the adherent bacteria. The bacteria were counted and identified.
  
  
  RESULTS
  There were 14 colonized catheters treated with UV light. The catheters were primarily colonized with coagulase-negative staphylococci (60%) and Staphylococcus aureus (33%). There was a significant reduction in viable bacteria between the UV-treated versus untreated segments of each infected catheter (P = .04). In the seven treated catheters with >100,000 colony-forming units per cm2 of luminal surface area, there was a >99.5% reduction of viable bacteria in all UV-exposed samples, with no residual viable bacteria in four of seven (57%) of the samples.
  
  
  CONCLUSIONS
  This study demonstrates the technical feasibility and benchtop efficacy of using fiber optics to deliver UV light into the lumen of a colonized dialysis catheter and inactivating bacteria on the intraluminal surface.
authors.affiliation: Department of Radiolosgy, University Hospitals Case Medical Center, Cleveland, Ohio. Electronic address: rogerlin@rogerlin.com.
authors.forename: Roger C
authors.initials: RC
authors.lastname: Lin
authors.affiliation: Division of Interventional Radiology and Image Guided Medicine, Emory University School of Medicine, Atlanta, Georgia.
authors.forename: J David
authors.initials: JD
authors.lastname: Prologo
mesh_terms: D002408:Catheters, Indwelling / Q000382:microbiology*; D002470:Cell Survival / Q000187:drug effects; D004203:Disinfection / Q000295:instrumentation*; D004866:Equipment Contamination / Q000517:prevention & control; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005336:Fiber Optic Technology / Q000295:instrumentation*; D008029:Lighting / Q000295:instrumentation*; D050296:Microbial Viability / Q000528:radiation effects*; D006435:Renal Dialysis / Q000295:instrumentation*; D014466:Ultraviolet Rays