角膜致病性丝状真菌药敏纸片扩散法与微量稀释法的对比研究

Comparison of the disk diffusion with the microdilution method for testing antifungai susceptibility of filamentous fungus

目的对比临床常用的纸片扩散法与标准微量稀释法检测丝状真菌体外药物敏感的一致性。设计实验性研究。研究对象镰刀菌属20株和曲霉菌属18株,均分离自北京同仁医院眼科中心送检的角膜标本。方法用纸片扩散法与NCCLS提出的微量稀释法(M38-P方案)平行检测丝状真菌体外药物的敏感性,对比两种方法结果的一致性。参试药物包括那他霉素、特比萘芬、两性霉素B、伊曲康唑、氟康唑、氟胞嘧啶、咪康唑、酮康唑。主要指标纸片扩散法的抑菌环直径(mm)和微量稀释法的最小抑菌浓度(μg/ml)。结果纸片扩散法与微量稀释法对比发现:对于镰刀菌属,两者结果的符合率大于80%者有:那他霉素(100%)、伊曲康唑(100%)、氟胞嘧啶(100%)、两性霉素B(88%)、咪康唑(85%)、氟康唑(85%)、酮康唑(80%);符合率低于80%者有:特比萘芬(0%)。对于曲霉菌属,符合率大于80%者有:氟康唑(100%)、咪康唑(97%)、特比萘芬(94%)、酮康唑(94%)、氟胞嘧啶(83%);符合率低于80%者有:那他霉素(72%)、伊曲康唑(72%)、两性霉素B(67%)。结论纸片扩散法与微量稀释法检测多数药物的一致性较高。由于纸片扩散法具有简便、快速等优点,适用于眼科实验室。

Objective To compare of the disk diffusion with the microdilution method for testing antifungal susceptibility of Fusarium spp. and Aspergillus spp. Design Experimental study. Participants Thirty-eight filamentous fungus isolated from clinical corneal specimens. Methods The sandard disk diffusion and the microdilution were performed according to the conventional method and National Committee for Clinical Laboraty Standards. The present study evaluate in vitro fungistastic activities of natamycine, terbinafine, amphotericin B, itroconazole, fluconazole, flucytosine, miconazole, and ketoconazole. Finally, the agreement were compared between the two methods. Main Outcome Measures The inhibition zones （mm） of disk diffusion and the minimal inhibitory concentrations （μg/ml） of microdilution method. Results When Fusarium spp. were tested, the agreement between the two methods was seen in natamycine （100%）, itroconazole （100%）, fluconazole （100%）, amphotericin B （88%）, miconazole （85%）, fluconazole （85%）, ketoconazole （80%）, and terbinafine （0%）. When Aspergillus spp. were tested, the agreement was seen in fluconazole （100%）, miconazole （97%）, terbinafine （94%）, ketoconazole （80%）, fluconazole （83%）, natamycine （72%）, itroconazole （72%）, and amphotericin B （67%）. Conclusion The disk diffusion method appears to be a suitable alternative procedure for testing most of the antifungal susceptibility of filamentous fungus.