米卡芬净等对抗白念珠菌生物膜的体外研究

目的 探讨体外白念珠菌生物膜对米卡芬净的敏感性。方法 通过建立白念珠菌生物膜的体外模型，用抗真菌药物敏感实验法和甲基四氮盐（XTT）减低法来评价白念珠菌生物膜对氟康唑、两性霉素B、米卡芬净的敏感性。结果 30株白念珠菌生物膜中，所有菌株对氟康唑均耐药（SMIC80≥64μg／ml）；4株对两性霉素B敏感（SMIC80≤1μg／ml），26株对两性霉素B耐药（MIC80＞1μg／ml）；27株对米卡芬净敏感（SMIC80＜ 16μg／ml），3株对米卡芬净耐药(SMIC80≥16μg／ml)。经统计学分析，就白念珠菌生物膜的敏感性而言，米卡芬净和氟康唑之间有统计学意义（χ2=736.36, P<0.0125），米卡芬净和两性霉素B之间有统计学意义（χ2=529.95, P<0.0125），氟康唑和两性霉素B之间无统计学意义（χ2=2.29,P>0.0125）。结论 白念珠菌生物膜对目前常用的系统性抗真菌药物两性霉素B、氟康唑明显耐药，而对米卡芬净比较敏感。

In vitro activity of micafungin against Candida albicans biofilms

Objective To explore the susceptibility of Candida albicans biofilms to micafungin. Methods In vitro model of C. Albicans biofilm was established in 96-well microtiter plates with 30 C. Albicans isolates from the Department of Mycology, Changhai Hospital, Shanghai. The susceptibility of C. Albicans biofilms to fluconazole, amphotericine B and micafungin was evaluated by colorimetric XTT-reduction assay. Sessile MIC80 (SMIC80), defined as the lowest antifungal concentration at which an 80% reduction in fungal growth was achieved, was determined. Results Of the 30 C. Albicans isolates grown in sessile states, all were resistant to fluconazole (SMIC80≥64 μg/mL), 4 sensitive to amphotericine B (SMIC80≤1 μg/mL), 26 resistant to amphotericine B (SMIC80 > 1 μg/mL), 27 sensitive to micafungin (SMIC80 < 16 μg/mL), 3 resistant to micafungin (SMIC80 >16 μg/mL). Statistical analysis revealed a significant difference in the activity against C. Albicans biofilms between micafungin and fluconazole (χ2=736.36, P<0.01), micafungin and amphotericine B (χ2=529.95, P<0.01), but not between anphotericine B and fluconazole (χ2=2.29, P>0.05). Conclusion C. Albicans biofilms are resistant to routine antifungal agents such as fluconazole and amphotericine B, but relatively more sensitive to micafungin.