Guelfand L, Grisolía P, Bozzano C, Kaufman S
Laboratorio de Microbiología, Hospital J. A. Fernández, Cerviño 3356, 1425 Buenos Aires, Argentina.
Rev Argent Microbiol. 2003 Jan-Mar;35(1):49-53.
We evaluated different methods for the routine identification of medically important yeasts. A total of 150 clinical isolates: 25 C. albicans, 25 C. tropicalis, 25 C. glabrata, 25 C. parapsilosis, 8 C. guilliermondii, 11 C. krusei and 31 Cryptococcus neoformans were tested by Yeast Biochemical Card bioMerieux Vitek (YBC), CHROMagar Candida (CHR). The addition of yeast morphology in Corn Meal agar-Tween 80 (AM) to YBC and CHR was also evaluated. The reference methods used were: API 20C, germ tube formation, AM, Christensen urea and Birdseed agar. YBC identified 135 yeasts with an overall accuracy of 90%. Sensitivity (S) and specificity (E) were: 92-98% for C. albicans and C. tropicalis; 84-99% for C. papapsilosis; 100-99% for C. glabrata; 91-100% for C. krusei; 63-98% for C. guilliermondii and 90-99% for Cryptococcus neoformans, respectively. CHR identified correctly 100% for C. albicans, 92% for C. tropicalis and 91% for C. krusei. Both methods combined with AM provided 100% S and E. We found that YBC system was appropriate for identification of yeasts isolated from human sources. CHR was effective and easy to use for identification of C. albicans, C. tropicalis and C. krusei. The routine use of AM with both methods is recommended.
我们评估了用于常规鉴定医学重要酵母菌的不同方法。共对150株临床分离株进行了检测,其中包括25株白色念珠菌、25株热带念珠菌、25株光滑念珠菌、25株近平滑念珠菌、8株季也蒙念珠菌、11株克柔念珠菌和31株新型隐球菌,采用了生物梅里埃Vitek酵母生化鉴定卡(YBC)、科玛嘉念珠菌显色培养基(CHR)进行检测。还评估了将玉米粉琼脂 - 吐温80(AM)中的酵母形态学检查与YBC和CHR相结合的方法。所使用的参考方法有:API 20C、芽管形成试验、AM、克里斯滕森尿素试验和鸟籽琼脂试验。YBC鉴定出135株酵母菌,总体准确率为90%。白色念珠菌和热带念珠菌的敏感性(S)和特异性(E)分别为92 - 98%;近平滑念珠菌为84 - 99%;光滑念珠菌为100 - 99%;克柔念珠菌为91 - 100%;季也蒙念珠菌为63 - 98%;新型隐球菌为90 - 99%。CHR对白色念珠菌的鉴定正确率为100%,对热带念珠菌为92%,对克柔念珠菌为91%。两种方法与AM相结合均提供了100%的敏感性和特异性。我们发现YBC系统适用于鉴定从人体分离出的酵母菌。CHR对于白色念珠菌、热带念珠菌和克柔念珠菌的鉴定有效且易于使用。建议将AM常规用于这两种方法。