Infectious Diseases Department, Hospital Universitari Vall d'Hebron, Barcelona, Spain.
J Antimicrob Chemother. 2010 Mar;65(3):525-30. doi: 10.1093/jac/dkp499. Epub 2010 Jan 18.
The effectiveness of linezolid, vancomycin, ciprofloxacin and gentamicin for treating experimental Staphylococcus aureus catheter-related infection by the antibiotic-lock technique was assessed.
Two methicillin-susceptible (MSSA) ATCC strains and two methicillin-resistant (MRSA) clinical strains were used. New Zealand white rabbits were surgically implanted with a silicone intravenous catheter. Infection was induced by filling and locking the catheter with 0.3 mL of broth culture containing S. aureus, with turbidity equivalent to that of a 0.5 McFarland standard. Eighteen hours later the antibiotic-lock technique was started and continued for 24 h. Treatment groups were: control without treatment; 2000 mg/L linezolid; 2000 mg/L vancomycin; 2000 mg/L ciprofloxacin; and 40,000 mg/L gentamicin.
Linezolid and vancomycin showed equivalent activity, achieving significant reductions in log(10) cfu recovered from catheter tips in one MSSA strain (>1.12) and one MRSA strain (>0.77) as compared with controls (P < 0.05). Ciprofloxacin achieved significant log(10) cfu reductions in MSSA strains relative to controls (>2.51, P < 0.01). In one MSSA strain, ciprofloxacin showed a larger reduction in log(10) cfu than linezolid or vancomycin (P < 0.01). Gentamicin was the only antibiotic achieving negative catheter tip cultures (up to 87.5% in MSSA and up to 40% in MRSA, P < 0.01), and showed the greatest log(10) cfu reduction compared with controls (>4.25 in MSSA and >2.93 in MRSA, P < 0.05) and significant differences relative to the remaining treatment groups (P < 0.05 in both MSSA and MRSA).
Gentamicin showed the highest activity against both MSSA and MRSA biofilms.
通过抗生素锁定技术评估了利奈唑胺、万古霉素、环丙沙星和庆大霉素治疗金黄色葡萄球菌导管相关感染的效果。
使用了 2 株耐甲氧西林金黄色葡萄球菌（MSSA）ATCC 株和 2 株耐甲氧西林金黄色葡萄球菌（MRSA）临床株。新西兰白兔通过手术植入硅胶静脉导管。将含有金黄色葡萄球菌的 0.3 毫升肉汤培养物填充并锁定导管，浊度相当于 0.5 McFarland 标准，从而诱导感染。18 小时后开始使用抗生素锁定技术并持续 24 小时。治疗组为：无治疗对照；2000mg/L 利奈唑胺；2000mg/L 万古霉素；2000mg/L 环丙沙星；40000mg/L 庆大霉素。
利奈唑胺和万古霉素表现出相当的活性，与对照组相比，1 株 MSSA 株（>1.12）和 1 株 MRSA 株（>0.77）从导管尖端回收的对数 10 cfu 显著减少（P < 0.05）。环丙沙星与对照组相比，对 MSSA 株的对数 10 cfu 减少有显著差异（>2.51，P < 0.01）。在 1 株 MSSA 株中，与利奈唑胺或万古霉素相比，环丙沙星对 log 10 cfu 的减少更大（P < 0.01）。庆大霉素是唯一一种获得阴性导管尖端培养物的抗生素（在 MSSA 中高达 87.5%，在 MRSA 中高达 40%，P < 0.01），与对照组相比，对 log 10 cfu 的减少最大（在 MSSA 中>4.25，在 MRSA 中>2.93，P < 0.05），与其余治疗组相比差异显著（在 MSSA 和 MRSA 中均为 P < 0.05）。
庆大霉素对 MSSA 和 MRSA 生物膜表现出最高的活性。
