Tetrasodium EDTA as a novel central venous catheter lock solution against biofilm

Background:Central venous catheter (CVC)-related bloodstream infections (BSIs) are known to increase rates of morbidity and mortality in both inpatients and outpatients, including hematology-oncology patients and those undergoing hemodialysis or home infusion therapy. Biofilm-associated organisms on the lumens of these catheters have reduced susceptibility to antimicrobial chemotherapy. This study tested the efficacy of tetrasodium EDTA as a catheter lock solution on biofilms of several clinically relevant microorganisms.Methods:Biofilms ofStaphylococcus epidermidis, methicillin-resistantS. aureus, Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumoniae, andCandida albicanswere grown to levels of approximately 1 × 105colony-forming units (CFU)/cm−1on CVC segments in a model system, then subjected to the tetrasodium EDTA lock treatment.Results:Comparisons of biofilms before and after exposure to the 40-mg/mL−1tetrasodium EDTA lock for 21 hours showed that the biofilm viable cell counts of all organisms tested were significantly reduced (P< .05) after exposure to the treatment.Conclusion:Antimicrobial lock treatment using 40 mg/mL−1of tetrasodium EDTA for at least 21 hours could significantly reduce or potentially eradicate CVC-associated bio-films of clinically relevant microorganisms (Infect Control Hosp Epidemiol2005;26:515-519).