PD460 - EMERGING ANTIBIOFILM STRATEGIES FOR CLABSI PREVENTION: FOCUS ON QUATERNARY AMMONIUM COMPOUNDS

PD460

EMERGING ANTIBIOFILM STRATEGIES FOR CLABSI PREVENTION: FOCUS ON QUATERNARY AMMONIUM COMPOUNDS

J. Víšek^1,*, L. Ryskova², M. Hympanova³, J. Bavlovic⁴, M. Vajrychova³, O. Soukup³, V. Blaha¹

¹3rd Department of Internal Medicine – Metabolic Care and Gerontology, ²Department of Clinical Microbiology, University Hospital and Medical faculty in Hradec Kralove, ³Biomedical Research Centre, University Hospital Hradec Kralove, ⁴Department of Molecular Pathology and Biology, Military Faculty of Medicine, University of Defence, Hradec Králové, Czech Republic

 

Rationale: Central venous catheters are essential for parenteral nutrition and long‑term intravenous therapy. Central line–associated bloodstream infections (CLABSI) remain a serious complication associated with increased mortality and healthcare costs. Bacterial biofilm formation on catheter surfaces plays a key role in infection persistence and markedly reduces susceptibility to antibiotics and antimicrobial lock solutions.

 

 

 

 

Methods:  

In vitro antimicrobial activity of taurolidine‑ and EDTA‑based catheter lock solutions and selected quaternary ammonium compounds (QACs) was evaluated. Minimal inhibitory concentrations (MIC) were determined against reference and multidrug‑resistant strains of Staphylococcus aureus and Pseudomonas aeruginosa. Antibiofilm activity was assessed using minimal biofilm eradication concentration (MBEC) testing on mature S. aureus biofilms.

 

 

 

 

Results:  

Taurolidine (1.35–2%) and EDTA (4%) showed activity against planktonic bacteria (MIC ≈ 1000 mg/L and 100–200 mg/L, respectively) but failed to eradicate biofilm even at very high concentrations (MBEC > 20 000 mg/L for taurolidine, ≥ 500 mg/L for EDTA). In contrast, QACs exhibited markedly lower MIC values (0.4–2 mg/L) and achieved biofilm eradication at low concentrations (MBEC 25–50 mg/L), including after short exposure times.

 

 

Conclusion: Effective CLABSI prevention requires strategies targeting catheter‑associated biofilm. Quaternary ammonium compounds demonstrate substantially superior in vitro antibiofilm activity compared with current lock solutions. Their potential future use may include combination locks or non‑systemic applications such as coated catheters; however, further safety evaluation is required.

 

 

 

 

Disclosure of Interest: None declared