Abstract:
Since its inception in 2002, the EUCAST Antifungal Susceptibility Testing Subcommittee (AFST) has developed and refined susceptibility testing methods for yeast, moulds and dermatophytes, and established epidemiological cut-off values and breakpoints for antifungals. For yeast, three challenges have been addressed. Interpretation of trailing growth in fluconazole susceptibility testing, which has been proven without impact on efficacy if below the 50% endpoint. Variability in rezafungin MIC testing due to laboratory conditions, which has been solved by the addition of Tween 20 to the growth medium in E.Def 7.4. And third, interpretation of MICs for rare yeast with no breakpoints, where recommendations have been established for MIC-based clinical advice. For moulds, refinements include the validation of spectrophotometer reading for A. fumigatus to facilitate objective MIC determination, and for dermatophytes the establishment of a microdilution method with automated reading and a selective medium to minimise the risk of contaminations. Recent initiatives involve development and validation of agar-based screening assays for detection of potential azole and echinocandin resistance in A. fumigatus and Aspergillus species, respectively, and of terbinafine resistance in Trichophyton species. Moreover, the development of a EUCAST guidance document for molecular resistance testing represents an advancement, particularly for identifying target gene alterations associated with resistance. In summary, EUCAST AFST continues to play a pivotal role in standardizing AFST and facilitating accurate interpretation of susceptibility data for clinical decision-making. Adoption of EUCAST breakpoints for commercial test methods, however, requires thorough validation to ensure concordance with EUCAST reference testing species-specific MIC distributions.
摘要:
自2002年成立以来,EUCAST抗真菌药敏试验小组委员会(AFST)已开发并完善了酵母药敏试验方法,霉菌和皮肤癣菌,并建立了抗真菌药的流行病学截止值和断点。对于酵母,解决了三个挑战。氟康唑药敏试验中拖尾生长的解释,这已被证明,如果低于50%终点,对疗效没有影响。由于实验室条件,rezafunginMIC测试的可变性,已通过在E.Def7.4中的生长培养基中添加Tween20来解决。第三,对没有断点的稀有酵母的MIC的解释,已经建立了基于MIC的临床建议。对于模具,改进包括验证烟曲霉的分光光度计读数,以促进客观MIC测定,对于皮肤癣菌,建立具有自动读数和选择性培养基的微量稀释方法,以最大程度地减少污染的风险。最近的举措涉及开发和验证基于琼脂的筛选测定法,以检测烟曲霉和曲霉种的潜在唑和棘白菌素抗性,分别,毛癣菌对特比萘芬的抗性。此外,EUCAST分子抗性测试指导文件的开发代表了一种进步,特别是用于鉴定与抗性相关的靶基因改变。总之,EUCASTAFST在标准化AFST和促进临床决策敏感性数据的准确解释方面继续发挥关键作用。采用EUCAST断点用于商业测试方法,然而,需要进行彻底验证,以确保与EUCAST参考测试特定物种的MIC分布保持一致。