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Abstract：
(1) Background: Aspergillus flavus is a cosmopolitan mold with medical, veterinary, and agronomic concerns. Its morphological similarity to other cryptic species of the Flavi section requires molecular identification techniques that are not routinely performed. For clinical isolates of Aspergillus section Flavi, we present the molecular identification, susceptibility to six antifungal agents, and clinical context of source patients. (2) Methods: One hundred forty fungal clinical isolates were included in the study. These isolates, recovered over a 15-year period (2001-2015), were identified based on their morphological characteristics as belonging to section Flavi. After the subculture, sequencing of a part of the β-tubulin and calmodulin genes was performed, and resistance to azole antifungals was screened on agar plates containing itraconazole and voriconazole. Minimum inhibitory concentrations were determined for 120 isolates by the European Committee on Antimicrobial Susceptibility Testing (EUCAST) broth microdilution method. (3) Results: Partial β-tubulin and calmodulin sequences analysis showed that 138/140 isolates were A. flavus sensu stricto, 1 isolate was A. parasiticus/sojae, and 1 was A. nomiae. Many of the isolates came from samples collected in the context of respiratory tract colonization. Among probable or proven aspergillosis, respiratory infections were the most frequent, followed by ENT infections. Antifungal susceptibility testing was available for isolates (n = 120, all A. flavus ss) from one hospital. The MIC range (geometric mean MIC) in mg/L was 0.5-8 (0.77), 0.5-8 (1.03), 0.125-2 (0.25), 0.03-2 (0.22), 0.25-8 (1.91), and 0.03-0.125 (0.061) for voriconazole, isavuconazole, itraconazole, posaconazole, amphotericin B, and caspofungin, respectively. Two (1.67%) isolates showed resistance to isavuconazole according to current EUCAST breakpoints with MICs at 8 mg/L for isavuconazole and voriconazole. One of these two isolates was also resistant to itraconazole with MIC at 2 mg/L. (4) Conclusions: The present characterization of a large collection of Aspergillus belonging to the Flavi section confirmed that A. flavus ss is the predominant species. It is mainly implicated in respiratory and ENT infections. The emergence of resistance highlights the need to perform susceptibility tests on section Flavi isolates.
摘要：
(1)研究背景:黄曲霉是一种具有医学、兽医,和农艺问题。它与Flavi部分的其他隐蔽物种的形态相似性需要不常规进行的分子鉴定技术。对于曲霉菌的临床分离株，我们提出了分子鉴定，对六种抗真菌药物的敏感性，和来源患者的临床背景。（2）方法：本研究包括440株真菌临床分离株。这些隔离物,在15年期间(2001-2015年)恢复，根据它们的形态特征被鉴定为属于Flavi部分。亚文化之后,对β-微管蛋白和钙调蛋白基因的一部分进行测序，在含有伊曲康唑和伏立康唑的琼脂平板上筛选了对唑类抗真菌剂的抗性。通过欧洲抗菌药物敏感性测试委员会（EUCAST）肉汤微量稀释法确定了120种分离物的最小抑制浓度。（3）结果：部分β-微管蛋白和钙调蛋白序列分析显示，138/140个分离株为黄曲霉，1个分离物是A.parasiticus/sojae，1是A.nomiae。许多分离物来自在呼吸道定植的背景下收集的样品。在可能或已证实的曲霉病中，呼吸道感染是最常见的，其次是耳鼻喉科感染。一家医院的分离株（n=120，全部为黄曲霉）可进行抗真菌药敏试验。以mg/L为单位的MIC范围（几何平均MIC）为0.5-8（0.77），0.5-8(1.03),0.125-2（0.25），0.03-2(0.22),0.25-8（1.91），伏立康唑为0.03-0.125(0.061)，伊沙武康唑,伊曲康唑,泊沙康唑,两性霉素B,和卡波芬金,分别。根据当前的EUCAST断点，两个（1.67％）分离株显示出对伊沙武康唑的耐药性，伊沙武康唑和伏立康唑的MIC为8mg/L。这两个分离株之一也对伊曲康唑具有2mg/L的MIC。（4）结论：目前对属于Flavi部分的大量曲霉的表征证实，黄曲霉是主要物种。它主要涉及呼吸道和耳鼻喉科感染。耐药性的出现凸显了对Flavi分离株进行药敏试验的必要性。
