Department of Bioclinical Sciences, Faculty of Dentistry, Health Sciences Center, Kuwait University, Jabriya, Kuwait. arjuna @ hsc.edu.kw
Med Princ Pract. 2012;21(4):375-8. doi: 10.1159/000336586. Epub 2012 Mar 3.
To determine if D-xylose (XYL) and/or α-methyl-D-glucoside (MDG) assimilation can be used reliably as a rapid test to differentiate Candida dubliniensis from Candida albicans at an earlier time point such as 2 h after inoculation.
Thirty isolates of C. albicans and C. dubliniensis recovered from anatomical sites and clinical specimens were used. Isolates were inoculated into the API 20C AUX yeast identification system, and incubated at 30°C. XYL and MDG assimilations were read at 2-hour intervals beginning 2 h after the initial inoculation and up to 24 h of incubation; thereafter, results were read after 48 and 72 h.
Twenty-nine (97%) C. albicans isolates had assimilated XYL at 16 h and, by 24 h, all isolates were positive for XYL assimilation. None of the C. dubliniensis isolates assimilated XYL. The MDG assimilation revealed that 24, 40, 92 and 100% of C. albicans isolates became positive after 16, 24, 48 and 72 h of incubation, respectively, whereas only 3% of C. dubliniensis isolates assimilated MDG after 72 h.
The findings showed that it is possible to rapidly differentiate C. albicans from C. dubliniensis isolates using the API 20C AUX carbohydrate assimilation kits after 16 h of incubation at 30°C based on the XYL assimilation.
确定 D-木糖 (XYL) 和/或 α-甲基-D-吡喃葡萄糖苷 (MDG) 的同化是否可以可靠地用作快速试验，以便在接种后 2 小时等更早的时间点将杜波依斯念珠菌与白念珠菌区分开来。
使用了从解剖部位和临床标本中回收的 30 株白念珠菌和杜波依斯念珠菌。将分离株接种到 API 20C AUX 酵母鉴定系统中，并在 30°C 下孵育。在初始接种后 2 小时开始，每隔 2 小时读取 XYL 和 MDG 的同化情况，直到孵育 24 小时；此后，在 48 和 72 小时后读取结果。
29（97%）株白念珠菌在 16 小时时同化了 XYL，到 24 小时时，所有分离株对 XYL 同化均呈阳性。没有一株杜波依斯念珠菌分离株同化了 XYL。MDG 同化表明，24、40、92 和 100%的白念珠菌分离株在孵育 16、24、48 和 72 小时后分别变为阳性，而只有 3%的杜波依斯念珠菌分离株在 72 小时后同化了 MDG。
研究结果表明，在 30°C 孵育 16 小时后，使用 API 20C AUX 碳水化合物同化试剂盒，可以根据 XYL 的同化情况，快速区分白念珠菌和杜波依斯念珠菌分离株。
