Faculdade de Farmácia, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.
APMIS. 2010 Nov;118(11):873-7. doi: 10.1111/j.1600-0463.2010.02681.x. Epub 2010 Sep 14.
The aim of this study was to use a practical method to determine the minimal biofilm eradication concentration (MBEC) of vancomycin and to compare the MBEC with minimal inhibitory concentration (MIC) for biofilm-producing and non-biofilm-producing isolates of staphylococci. Forty Staphylococcus spp. isolates from central venous catheter, from distinct patients, were selected for this study. The vast majority (28/30) of isolates which were biofilm-producing, presented high MBEC values (≥8 μg/mL) and could be considered as non-susceptible to vancomycin. All non-biofilm-producing isolates presented low MBEC (≤2 μg/mL) and were susceptible to vancomycin, according to CLSI breakpoints. While the MBEC and MIC values for biofilm-producing isolates differ significantly, the MBEC and MIC values for non-biofilm producers were the same. The method we have used proved to be a feasible and rapid technique to measure MBEC of Staphylococcus spp. biofilms. The method presented herein might be an alternative tool to evaluate the antibiotic susceptibility in the biofilm mode of growth; the MBEC may be a more appropriate approach to correlate the susceptibility in vitro with clinical outcome resulting from the treatment of Staphylococcus spp. infection.
本研究的目的是使用一种实用的方法来确定万古霉素的最小生物膜清除浓度（MBEC），并比较生物膜产生和非生物膜产生的葡萄球菌分离株的 MBEC 与最小抑菌浓度（MIC）。从不同患者的中心静脉导管中选择了 40 株金黄色葡萄球菌分离株进行本研究。绝大多数（28/30）产生物膜的分离株具有较高的 MBEC 值（≥8 μg/mL），可被认为对万古霉素不敏感。所有非产生物膜的分离株的 MBEC 较低（≤2 μg/mL），根据 CLSI 折点对万古霉素敏感。虽然产生物膜分离株的 MBEC 和 MIC 值有显著差异，但非产生物膜分离株的 MBEC 和 MIC 值相同。我们使用的方法被证明是一种可行且快速的技术，可以测量金黄色葡萄球菌生物膜的 MBEC。本文所述的方法可能是评估生物膜生长模式下抗生素敏感性的一种替代工具；MBEC 可能是一种更合适的方法，可将体外敏感性与金黄色葡萄球菌感染治疗的临床结果相关联。
