title: Methods for removing bacterial biofilms: in vitro study using clinical chronic rhinosinusitis specimens.
abstract: BACKGROUND
  Bacterial biofilms may be involved in refractory chronic rhinosinusitis (CRS). In vitro, we studied methods for removing biofilms formed by Staphylococcus aureus and Pseudomonas aeruginosa.
  
  
  METHODS
  Bacterial isolates were obtained from patients with refractory CRS and were plated and treated with either static administration of citric acid/zwitterionic surfactant (CAZS), saline delivered with hydrodynamic force, or CAZS delivered hydrodynamically. Results were assessed by counting colony-forming units (CFUs) and by confocal scanning laser microscopy (CSLM).
  
  
  RESULTS
  All treatments produced significant reductions in CFU counts (p >or= 0.002). Hydrodynamic CAZS provided the greatest reduction, decreasing CFU counts from control values by 3.9 +/- 0.3 logs and 5.2 +/- 0.5 logs for S. aureus and P. aeruginosa, respectively (99.9% reduction; p = 0.001). CSLM showed decreases in biofilm coverage.
  
  
  CONCLUSIONS
  Hydrodynamic delivery of a soap-like surfactant and a calcium-ion sequestering agent may disrupt biofilms associated with CRS. Our results may be relevant to a new approach to refractory CRS.
authors: Centre Hospitalier de l'Université de Montréal and McGill University Health Center, Montreal, Quebec, Canada.
authors: Martin
authors: M
authors: Desrosiers
authors: Matthew
authors: M
authors: Myntti
authors: Garth
authors: G
authors: James
mesh_terms: D018441:Biofilms; D019343:Citric Acid / Q000737:chemistry; D016503:Drug Delivery Systems; D004724:Endoscopy; D004867:Equipment Design; D006801:Humans; D008829:Microbiology; D018613:Microscopy, Confocal; D011550:Pseudomonas aeruginosa / Q000378:metabolism*; D012220:Rhinitis / Q000382:microbiology*; D012852:Sinusitis / Q000382:microbiology*; D013211:Staphylococcus aureus / Q000378:metabolism*; D013501:Surface-Active Agents / Q000008:administration & dosage
chemical_list: D013501:Surface-Active Agents; D019343:Citric Acid