title: Structural features of tympanostomy tube biofilm formation in ciprofloxacin-resistant Pseudomonas otorrhea.
abstract: OBJECTIVE
  Bacterial biofilm formation has been implicated in the high rate of persistent otorrhea after tympanostomy tube insertion. In this study, we evaluated Pseudomonal biofilm formation from intractable post tympanostomy tube otorrhea in children.
  
  
  METHODS
  Twelve patients (seven males, five females) with unilateral post tympanostomy tube P. aeruginosa otorrhea were evaluated prospectively. All patients were treated with ciprofloxacin otic drops but the otorrhea failed to resolve. Ear discharge for culture was collected from the external auditory canal using a swab. The tympanostomy tubes were removed and collected for evaluation of biofilm formation using a scanning electron microscopy.
  
  
  RESULTS
  In all cases, ciprofloxacin-resistant P. aeruginosa was the only organism grown. The surface of the silicone tube contained undulations or microfissures throughout. The thick biofilms present on most tube surfaces were densities with no intervening spaces, consistent with biofilms.
  
  
  CONCLUSIONS
  Biofilms can be directly observed by scanning electron microscopy. Therefore, our results demonstrate that bacterial aggregates called biofilms, that are resistant to treatment by antibiotics, can be detected by standard culture techniques, and may play a major etiologic role in posttympanostomy otorrhea.
authors.affiliation: Department of Otolaryngology, Chonnam National University Medical School, Gwangju, South Korea. chulsavio@hanmail.net
authors.forename: Chul-Ho
authors.initials: CH
authors.lastname: Jang
authors.forename: Yong-Bum
authors.initials: YB
authors.lastname: Cho
authors.forename: Cheol-Hee
authors.initials: CH
authors.lastname: Choi
mesh_terms: D000890:Anti-Infective Agents / Q000627:therapeutic use; D018441:Biofilms; D002648:Child; D002939:Ciprofloxacin / Q000627:therapeutic use; D024881:Drug Resistance, Bacterial; D005260:Female; D006801:Humans; D007440:Intubation / Q000295:instrumentation*; D008297:Male; D008876:Middle Ear Ventilation / Q000295:instrumentation*; D010034:Otitis Media with Effusion / Q000188:drug therapy / Q000382:microbiology* / Q000601:surgery; D011550:Pseudomonas aeruginosa / Q000502:physiology*
chemical_list: D000890:Anti-Infective Agents; D002939:Ciprofloxacin