地塞米松影响念珠菌对抗真菌药物敏感性的实验研究

目的 探讨地塞米松在体外试验中是否影响念珠菌对抗真菌药物的敏感性，以了解糖皮质激素与抗真菌药物直接作用于念珠菌时是否存在相互作用。方法 用微量液体培养基稀释法分别测定26株白念珠菌与地塞米松（0．2mg／ml）共同孵育前、孵育24～48h及7d时氟康唑、伊曲康唑、两性霉素B的最低抑菌浓度（MIC）值，并作对照。结果 白念珠菌与地塞米松孵育24～48h后、孵育后第7d氟康唑和伊曲康唑的MIC值升高，分别与孵育前的MIC值存在统计学差异，但孵育24～48h后的MIC与孵育后第7d的MIC无统计学差异；白念珠菌与地塞米松共同孵育24～48h后两性霉素B的MIC值也较孵育前升高，但第7d的MIC值与孵育前无差异。结论 地塞米松可增加三种抗真菌药物对于白念珠菌的MIC，但三种抗真菌药物间存在差异，表明地塞米松对于氟康唑和伊曲康唑体外抗白念珠菌的活性有拮抗作用，但没有时间依赖性，地塞米松对于两性霉素B的影响较氟康唑和伊曲康唑小，且影响时间较短。

Effect of dexamethasone on in vitro susceptibility test of Candida albicans to itraconazole, fluconazole and amphotericin B

Objective To investigate whether dexamethasone could change the in vitro susceptibility of Candida albicans to anti- fungal drugs,and analyse the interaction between glucocorticoid and antifungal drugs to fungi. Methods Microdilution antifungal susceptibility test was used to determine MIC of itraconazole, fluconazole,amphotericin B to 26 strains of Candida albicans before and after they incubated with dexamethasone,and MIC for each antifungal drug was compared. Rnsults MIC of itraconazole and fluconazole was enhanced after Candida albicans incubated with dexamethasone, but no difference between 24-48 hours and the 7^th day. MIC of amphotericin B was also changed after Candida albican incubated with dexamethasone, MIC of 24-48 hours increased after Candida albicans incubated with dexamethasone, but MIC at the 7^th day kept no chang. Conclusions Dexamethasone decreases Candida albican in vitro susceptibility to itraconazole ,fluconazole and amphotericin B. There is antagonism between dexamethasone and antifungal drugs in vitro. The influence of dexamethasone on amphotericin B is lighter than on itraconazole and fluconazole.