米卡芬净等对抗白念珠菌生物膜的体外研究

In vitro activity of mieafungin against Candida albicans biofilms

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（SMXC80≤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问差异有统计学意义（X2=736．36，P〈0．01），米卡芬净和两性霉素B之间差异有统计学意义（X2=529．95，P〈0．01），氟康唑和两性霉素B之间差异无统计学意义（矿=2．29，P〉0．05）。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。

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≥64μg/mL）, 4 sensitive to amphotericine B （SMIC80 ≤ 1μg/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 （X2= 736.36, P 〈 0.01）, micafungin and amphotericine B （X2 = 529.95, P 〈 0.01 ）, but not between anphotericine B and fluconazole 0f = 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.