Antibiofilm Activity of Different Washing Solutions against Biofilms in Cystic Fibrosis Patients' Nasal Cavities

Abstract Objective  Bacterial biofilm formation is a multistep process involving bacterial adhesion to inorganic or mucosal surfaces. We aimed to identify Staphylococcus aureus and Pseudomonas aeruginosa strains colonizing the respiratory tracts of cystic fibrosis (CF) patients and to gauge the antibiofilm potential of streptomycin and ozone solutions against them. Methods  Bacteria were obtained from CF patients' sputum samples processed in our microbiology laboratory over 1 year (2021–2022). A total of 26 nonduplicate strains (13 S. aureus and 13 P. aeruginosa ) were included in this study. Results  Both ozone and streptomycin solutions showed significant inhibitory activity. However, when faced with mature biofilm, the streptomycin solution had a significantly more substantial impact than the ozone solution. Furthermore, the ozone solution had no inhibitory effect on mature P. aeruginosa biofilm. Conclusion  Ozone and streptomycin solutions might be used as nasal irrigation to eliminate the biofilms in patients with CF in acute respiratory infections. However, our in vitro observations would need to be confirmed in vivo. In chronic inflammation, ozone solution cannot degrade the mature biofilm of P. aeruginosa , whereas streptomycin solution can degrade such biofilms. This result is promising in lessening the biofilms associated with these bacteria that colonize patients with CF.