title: Bacterial biofilms in chronic rhinosinusitis; distribution and prevalence.
abstract: CONCLUSIONS
  Biofilms were more prevalent in patients with CRSwNP compared to both CRSsNP and controls, and also on the ethmoid bulla compared to the middle turbinate, supporting a biofilm-related pathogenesis of CRSwNP.
  
  
  OBJECTIVE
  To investigate the prevalence of biofilms in patients with chronic rhinosinusitis with nasal polyps (CRSwNP) compared to patients with chronic rhinosinusitis without nasal polyps (CRSsNP) and controls. To examine the prevalence of biofilms in different anatomical localizations.
  
  
  METHODS
  Cross-sectional.
  
  
  METHODS
  This study comprised 27 patients with CRSsNP, 34 patients with CRSwNP, and 25 controls. Biopsies from the middle turbinate, the uncinate process, and the ethmoid bulla were harvested pre-operatively, snap frozen in isopentane, cooled, and stored at -80°C. Prepared with Invitrogens' Baclight LiveDead kit and investigated with confocal scanning laser microscopy.
  
  
  RESULTS
  Biofilms were studied in 33/34 (97%) CRSwNP, 22/27 (82%) CRSsNP, and 14/25 (56%) controls. The difference in point prevalence between patients with CRSwNP vs CRSsNP (p = 0.042, χ(2) = 4.12), CRSwNP vs Controls (p < 0.001, χ(2) = 15.0), and CRSsNP vs controls (p = 0.047, χ(2) = 3.96) were all significant. Biofilms were found in 43/54 (80%) ethmoid bulla, 39/55 (71%) uncinate process, and 31/50 (62%) middle turbinate. The difference between the ethmoid bulla and the middle turbinate locations (p = 0.047, χ(2) = 3.93) was significant.
authors.affiliation: a Department of Otorhinolaryngology , Akershus University Hospital , Norway.|b Department of Otorhinolaryngology , Østfold Regional Hospital , Østfold , Norway.|c University of Oslo , Norway.
authors.forename: Kjell
authors.initials: K
authors.lastname: Arild Danielsen
authors.affiliation: a Department of Otorhinolaryngology , Akershus University Hospital , Norway.|c University of Oslo , Norway.|d Drøbak ENT , Drøbak , Akershus , Norway.
authors.forename: Øystein
authors.initials: Ø
authors.lastname: Eskeland
authors.affiliation: e Department of Pathology , Akershus University Hospital , Norway.
authors.forename: Katrin
authors.initials: K
authors.lastname: Fridrich-Aas
authors.affiliation: e Department of Pathology , Akershus University Hospital , Norway.
authors.forename: Vivian
authors.initials: V
authors.lastname: Cecilie Orszagh
authors.affiliation: a Department of Otorhinolaryngology , Akershus University Hospital , Norway.|c University of Oslo , Norway.
authors.forename: Gregor
authors.initials: G
authors.lastname: Bachmann-Harildstad
authors.affiliation: a Department of Otorhinolaryngology , Akershus University Hospital , Norway.|c University of Oslo , Norway.|f Medivir , Oslo , Norway.
authors.forename: Espen
authors.initials: E
authors.lastname: Burum-Auensen
mesh_terms: D000328:Adult; D018441:Biofilms; D016022:Case-Control Studies; D002908:Chronic Disease; D003430:Cross-Sectional Studies; D005005:Ethmoid Sinus / Q000382:microbiology; D005260:Female; D006801:Humans; D008297:Male; D009298:Nasal Polyps / Q000150:complications / Q000382:microbiology; D015995:Prevalence; D012220:Rhinitis / Q000150:complications / Q000382:microbiology*; D012852:Sinusitis / Q000150:complications / Q000382:microbiology*; D014420:Turbinates / Q000382:microbiology
keywords: Sinusitis; biofilm; confocal microscopy; nasal polyps