Medline ® Abstracts for References 9,11
of 'Antibiotic lock therapy for treatment of catheter-related bloodstream infections'
Effect of polyurethane catheters and bacterial biofilms on the in-vitro activity of antimicrobials against Staphylococcus epidermidis.
Pascual A, Ramirez de Arellano E, Martínez Martínez L, Perea EJ
J Hosp Infect. 1993;24(3):211.
The effect of two polyurethane ['Cavafix Certo' (CAV); 'Viacath' (VIA)]catheters on the in-vitro activity of amikacin (AN), clindamycin (CM), cloxacillin (CX), ciprofloxacin (CIP), vancomycin (VA), teicoplanin (TEI) and daptomycin (DAP) against slime producing and non-producing Staphylococcus epidermidis strains was determined using a microdilution assay. None of the antimicrobial agents was significantly affected in the presence of the catheters. The susceptibility of S. epidermidis attached to CAV and VIA catheters was also evaluated. Minimum inhibitory concentration (MIC) values were similar when planktonic and attached bacteria were compared. Minimum bactericidal concentrations (MBCs) markedly increased in the presence of 6 and 48 h bacterial biofilms. These increases in MBC values occurred when either slime producing or non-producing strains were used, and in most cases were higher for CAV catheters than for VIA catheters. This phenomenon was shown not to be due to differences in bacterial adherence. It is concluded that the in-vitro bactericidal activity of certain antimicrobials markedly decreased when bacteria adhered to plastic catheters, but this effect could have been dependent partially on the nature of the catheters.
Department of Microbiology, University of Sevilla Medical School, Spain.
The antibiotic-lock technique for therapy of 'highly needed' infected catheters.
Clin Microbiol Infect. 2002;8(5):282.
Catheter-related bacteremia is a major complication in patients with long-term surgically implanted central venous catheters, which are difficult and expensive to remove. Conventional treatment fails in a significant number of cases, resulting in removal of the device. The antibiotic-lock technique involves instilling a high concentration of antibiotic into the catheter lumen, and allowing it to remain for a period of time. Results of several open studies, mainly involving patients receiving home parenteral nutrition, indicate that this method may be regarded as an alternative to the conservative treatment of noncomplicated intraluminal catheter-related bacteremia, in which infection may be treated without catheter removal. However, many questions about this therapeutic method remain to be resolved, including appropriate concentration of antibiotics, duration of treatment, and whether or not concomitant systemic antibiotic therapy is necessary. Prospective studies comparing the antibiotic-lock technique with conventional treatment are needed.
Infectious Disease Service, Hospital de Bellvitge, University of Barcelona, Spain. firstname.lastname@example.org