Binder Ulrike, Aigner Maria, Risslegger Brigitte, Hörtnagl Caroline, Lass-Flörl Cornelia, Lackner Michaela
Institute of Hygiene and Medical Microbiology, Medical University Innsbruck, 6020 Innsbruck, Austria.
J Fungi (Basel). 2019 Sep 4;5(3):83. doi: 10.3390/jof5030083.
Antifungal susceptibility testing (AFST) of clinical isolates is a tool in routine diagnostics to facilitate decision making on optimal antifungal therapy. The minimal inhibitory concentration (MIC)-phenomena (trailing and paradoxical effects (PXE)) observed in AFST complicate the unambiguous and reproducible determination of MICs and the impact of these phenomena on in vivo outcome are not fully understood. We aimed to link the MIC-phenomena with in vivo treatment response using the alternative infection model . We found that strains exhibiting PXE for caspofungin (CAS) had variable treatment outcomes in the model. In contrast, strains showing trailing for voriconazole failed to respond in vivo. Caspofungin- and voriconazole-susceptible strains responded to the respective antifungal therapy in vivo. In conclusion, MIC data and subsequent susceptibility interpretation of strains exhibiting PXE and/or trailing should be carried out with caution, as both effects are linked to drug adaptation and treatment response is uncertain to predict.
临床分离株的抗真菌药敏试验（AFST）是常规诊断中的一种工具，有助于就最佳抗真菌治疗做出决策。在AFST中观察到的最低抑菌浓度（MIC）现象（拖尾和矛盾效应（PXE））使MIC的明确和可重复测定变得复杂，并且这些现象对体内结果的影响尚未完全了解。我们旨在使用替代感染模型将MIC现象与体内治疗反应联系起来。我们发现，对卡泊芬净（CAS）表现出PXE的菌株在该模型中具有不同的治疗结果。相比之下，对伏立康唑表现出拖尾现象的菌株在体内没有反应。对卡泊芬净和伏立康唑敏感的菌株在体内对各自的抗真菌治疗有反应。总之，对于表现出PXE和/或拖尾现象的菌株，MIC数据及随后的药敏解释应谨慎进行，因为这两种效应都与药物适应性相关，且治疗反应难以预测。
