Department of Medical Microbiology, Postgraduate Institute of Medical Education and Research, Chandigarh, India.
Department of Medical Microbiology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
J Clin Microbiol. 2021 Jan 21;59(2). doi: 10.1128/JCM.00326-20.
Identification of is challenging and requires molecular or protein profiling-based approaches, availability of which is limited in many routine diagnostic laboratories, necessitating the development of a cost-effective, rapid, and reliable method of identification. The objective of this study was to develop a selective medium for identification. Eighteen and 30 non- yeasts were used for the standardization of the selective medium. Sodium chloride (10% to 13% concentration) and ferrous sulfate (8 mM to 15 mM) were added to yeast extract-peptone-dextrose (YPD) agar in various combinations followed by incubation at 37°C, 40°C, or 42°C for 2 to 3 days. For validation, 579 yeast isolates and 40 signal-positive Bactec blood culture (BC) broths were used. YPD agar comprising 12.5% NaCl and 9 mM ferrous sulfate incubated at 42°C for 48 h, named Selective Auris Medium (SAM), allowed selective growth of A total of 95% (127/133) of isolates tested grew on the standardized media within 48 h, and the remaining 6 isolates grew after 72 h, whereas the growth of 446 non- yeast isolates was completely inhibited. The specificity and sensitivity of the test medium were both 100% after 72 h of incubation. The positive and negative predictive values were also noted to be 100% after 72 h of incubation. The formulated selective medium can be used for the detection and identification of The SAM is inexpensive, can easily be prepared, and can be used as an alternative to molecular diagnostic tools in the clinical microbiology laboratory.
鉴别 具有挑战性，需要基于分子或蛋白质分析的方法，而这些方法在许多常规诊断实验室中都无法获得，因此需要开发一种经济有效、快速可靠的鉴定方法。本研究的目的是开发一种用于 鉴别的选择性培养基。使用 18 株 和 30 株非酵母对选择性培养基进行标准化。在不同组合中向酵母提取物-胰蛋白胨-葡萄糖（YPD）琼脂中添加氯化钠（10%-13%浓度）和硫酸亚铁（8mM-15mM），然后在 37°C、40°C 或 42°C 孵育 2-3 天。为了验证，使用了 579 株酵母分离株和 40 株信号阳性的 Bactec 血液培养（BC）肉汤。由 12.5%NaCl 和 9mM 硫酸亚铁组成的 YPD 琼脂在 42°C 孵育 48 小时，命名为选择性耳培养基（SAM），允许 选择性生长。在标准化培养基上，共 95%（127/133）的 株在 48 小时内生长，其余 6 株在 72 小时后生长，而 446 株非酵母分离株的生长完全受到抑制。孵育 72 小时后，该测试培养基的特异性和敏感性均为 100%。孵育 72 小时后，阳性和阴性预测值也均为 100%。所制定的选择性培养基可用于 和 的检测和鉴定。SAM 价格低廉，易于制备，可替代临床微生物学实验室中的分子诊断工具。
