两性霉素B和5-氟胞嘧啶的体外联合药敏试验

Susceptibility testing of yeasts to combination of amphotericin B and 5-flucytosine in vitro according to M27-A method

参照美国国家临床试验标准化委员会(NCCLS)提出的标准,采用棋盘微量稀释法对28株隐球菌和念珠菌进行两性霉素B和5-氟胞嘧啶的体外联合药敏试验。结果显示联合用药时各药物的最低抑菌浓度(minimal inhibitory concentration,MIC)几何均值比单独用药显著降低(P<0.01);两性霉素B和5-氟胞嘧啶的协同相加作用较为明显,而且未发现有拮抗作用,部分抑菌浓度指数(fractional inhibitory concentration index,FICI)的平均值为0.8。提示两性霉素B和5-氟胞嘧啶对致病酵母主要表现为协同相加作用。

This article is to study the interaction between amphotericin B and 5-flucytosine to yeasts in vitro. The checkerboard microdilution method was applied to study in vitro interaction according to M27-A method of NCCLS. Twenty-eight strains of yeasts were used for combination study. Compared with the single agents,there were significant reductions in the geometric mean of the minimal inhibitory concentration of the combination(P<0. 01). Synergetic and additive interactions were observed obviously without antagonism. The average value of fractional inhibitory concentration index was 0. 8. Antifun-gal synergy exists between amphotericin B and 5-flucytosine against pathogenic yeasts.