Anti-Biofilm Effect of Octenidine and Polyhexanide on Uropathogenic Biofilm-Producing Bacteria

Abstract

<b><i>Background:</i></b> A catheter allowing a release of antibacterial substances such as antiseptics into the bladder could be a new way of preventing biofilm formation and subsequent catheter-associated urinary tract infections. <b><i>Methods:</i></b> Minimal inhibitory and bactericidal concentration (MIC/MBC) determinations in cation-adjusted Mueller-Hinton broth and artificial urine were performed for 4 antiseptics against 3 uropathogenic biofilm producers, <i>Escherichia coli</i>, <i>Pseudomonas aeruginosa</i>, and <i>Proteus mirabilis</i>. Furthermore, effects of octenidine and polyhexanide against catheter biofilm formation were determined by quantification of biofilm-producing bacteria. <b><i>Results:</i></b> Sodium hypochlorite showed MIC/MBC values between 200 and 800 mg/L for all strains tested. Triclosan was efficient against <i>E. coli</i> and <i>P. mirabilis</i> (MIC ≤2.98 mg/L) but ineffective against <i>P. aeruginosa</i>. Octenidine and polyhexanide showed antibacterial activity against all 3 species tested (MIC 1.95–7.8 and 3.9–31.25 mg/L). Both octenidine and polyhexanide were able to prevent biofilm formation on catheter segments in a concentration dependent manner. Furthermore, adding 250 mg/L of each biocide disrupted biofilms formed by <i>E. coli</i> and <i>P. mirabilis</i>, whereas even 500 mg/L was not sufficient to completely destroy <i>P. aeruginosa</i> biofilms. <b><i>Conclusion:</i></b> Octenidine- and polyhexanide-containing antiseptics showed a broad effect against typical uropathogenic biofilm producers even in high dilutions. This study provides a basis for further investigation of the potential of octenidine and polyhexanide as prophylaxis or treatment of catheter biofilms.