新生隐球菌对立福康唑和氟康唑的体外敏感性实验

目的 了解临床和环境中分离所得的新生隐球菌对立福康唑和氟康唑的体外敏感性。方法 采用美国国家实验室标准委员会(NCCLS)M27-A方案推荐的酵母菌微量稀释法,检测77株来自临床和环境中分离所得新生隐球菌对立福康唑和氟康唑的MIC值。结果 氟康唑、立福康唑的MIC范围分别为2.0～128μg/mL、0.008～0.5μg/mL,前者MIC₅₀、MIC₉₀几何均数值分别为4μg/mL、8μg/mL,后者几何均数值分别为0.125μg/mL、0.25μg/mL。其中,对氟康唑敏感菌株占81.8%(63/77),中度敏感或剂量依赖性敏感菌株占16.9%(13/77),耐药菌株占1.3%(1/77)。中度敏感和耐药的14株菌中,临床分离株占85.7%,尽管在临床菌株与环境分离株间差异无显著性(P>0.05),但仍应引起临床医师重视。结论 虽然部分新生隐球菌对氟康唑出现中度敏感或耐药,但立福康唑对其均具有较好的体外抗菌活性,有望成为治疗隐球菌病药物的又一选择。

In Vitro Efficacy of Ravuconazole and Fluconazole Against Clinical and Environmental Isolates of Cryptococcus neoformans

Objective To evaluate the in vitro activities of ravuconazole and fluconazole against clinical and environmental isolates. Methods The in vitro activities of ravuconazole and fluconazole aganist 77 isolates of Cryptococcus neoformans were tested according to M27-A microdilution method recommended by National Committee for Clinical Laboratory Standards (NCCLS). Results The MICs of fluconazole ranged from 2.0 to 128 μg/mL, with the geometric mean MIC₅₀ and MIC₉₀ of 4 μg/mL, 8 μg/mL. The ravuconazole MICs ranged from 0.008 to 0.5 μg/mL, with the geometric mean MIC₅₀, MIC₉₀ of 0.125 μg/mL, 0.25 μg/mL. 81.8% (63/77) isolates were sensitive to fluconazole, 16.9% (13/77) isolates were dose-dependent sensitive to fluconazole, 1.3% (1/77) isolates were resistant to fluconazole. The clinical and environmental isolates had the similar MIC to fluconazole and ravuconazole (P>0.05). Conclusion It is encouraging that ravuconazole is effective against clinical and environmental isolates of C. neoformans, whether the isolates were sensitive to fluconazole or not.