Linares M J, Muñoz J F, Solís F, Rodríguez F C, Valero A, Casal M
Department of Microbiology, Faculty of Medicine, University of Córdoba, Córdoba.
Rev Esp Quimioter. 1998 Mar;11(1):64-9.
The E test is a quantitative technique for determining antimicrobial susceptibility; it is based on the diffusion of a stable predetermined gradient of a specific antifungal agent along an inert plastic strip which is applied to a solid culture medium. The E test is an alternative method for determining inhibitory concentrations of antimicrobial agents. The aim of the present study was to determine the in vitro susceptibility of different yeasts to 5 antifungal agents using the E test. The antifungal susceptibility of 87 strains, 73 of which were yeasts obtained from clinical samples, 11 were Prototheca strains and 3 controls, were examined using a gradient diffusion technique (E test). Of these isolates, 13% of Candida albicans were resistant to flucytosine, and 20%, 17% and 33% showed resistance to ketoconazole, itraconazole and fluconazole, respectively. All Candida krusei isolates showed resistance to flucytosine and fluconazole. The Candida parapsilosis and Candida tropicalis strains all presented in vitro susceptibility to all the agents tested. Prototheca strains were only susceptible in vitro to amphotericin B. It was found that the E test was easy to perform, and provided MIC values similar to those obtained with other well documented techniques. It was therefore concluded that the E test could be implemented as a standard procedure in clinical mycology laboratories.
E试验是一种用于确定抗菌药物敏感性的定量技术；它基于一种特定抗真菌药物的稳定预定梯度沿着一条应用于固体培养基的惰性塑料条扩散。E试验是确定抗菌药物抑制浓度的另一种方法。本研究的目的是使用E试验确定不同酵母菌对5种抗真菌药物的体外敏感性。使用梯度扩散技术（E试验）检测了87株菌株的抗真菌药敏性，其中73株是从临床样本中获得的酵母菌，11株是原藻菌株，3株为对照菌株。在这些分离株中，13%的白色念珠菌对氟胞嘧啶耐药，20%、17%和33%分别对酮康唑、伊曲康唑和氟康唑耐药。所有克鲁斯念珠菌分离株均对氟胞嘧啶和氟康唑耐药。近平滑念珠菌和热带念珠菌菌株对所有测试药物均表现出体外敏感性。原藻菌株仅在体外对两性霉素B敏感。研究发现，E试验易于操作，且提供的最低抑菌浓度（MIC）值与其他有充分文献记载的技术所获得的值相似。因此得出结论，E试验可作为临床真菌学实验室的标准程序实施。
