Randomized controlled trial of biofilm antimicrobial susceptibility testing in cystic fibrosis patients

J Cyst Fibros. 2015 Mar;14(2):262-6. doi: 10.1016/j.jcf.2014.09.013. Epub 2014 Oct 30.


This study aimed to determine whether antimicrobial susceptibility testing of Pseudomonas aeruginosa grown as a biofilm, rather than planktonically, improves efficacy of antibiotic treatment for pulmonary exacerbations. This was a multicenter randomized, double-blind controlled trial of 14 days of intravenous antibiotic treatment for pulmonary exacerbations chosen based on conventional vs. biofilm antimicrobial susceptibility results in CF patients with chronic P. aeruginosa infection. There were 74 exacerbations in 39 patients. A total of 46% (12/26) exacerbations in the conventional group compared to 40% (19/48) exacerbations in the biofilm group achieved a ≥3 log drop in P. aeruginosa sputum density (difference -0.03, 95% CI -0.5 to 0.4, p=0.9). Lung function improvements were similar in both groups. Biofilm antimicrobial susceptibility testing did not lead to improved microbiological or clinical outcomes compared to conventional methods in the treatment of pulmonary exacerbations in CF patients with chronic P. aeruginosa.

Trial registration: ClinicalTrials.gov NCT00786513.

Keywords: Antibiotics; Biofilm; Pseudomonas aeruginosa; Pulmonary exacerbation.

Publication types

  • Multicenter Study
  • Randomized Controlled Trial

MeSH terms

  • Anti-Bacterial Agents* / classification
  • Anti-Bacterial Agents* / therapeutic use
  • Biofilms* / drug effects
  • Biofilms* / growth & development
  • Canada
  • Child
  • Cystic Fibrosis* / complications
  • Cystic Fibrosis* / microbiology
  • Double-Blind Method
  • Female
  • Humans
  • Male
  • Microbial Sensitivity Tests* / methods
  • Microbial Sensitivity Tests* / statistics & numerical data
  • Pseudomonas Infections* / diagnosis
  • Pseudomonas Infections* / drug therapy
  • Pseudomonas Infections* / etiology
  • Pseudomonas aeruginosa* / drug effects
  • Pseudomonas aeruginosa* / physiology
  • Reproducibility of Results
  • Respiratory Function Tests / methods
  • Sputum / drug effects
  • Sputum / microbiology
  • Treatment Outcome


  • Anti-Bacterial Agents

Associated data

  • ClinicalTrials.gov/NCT00786513