Chen Jonathan H K, Yam Wing-Cheong, Ngan Antonio H Y, Fung Ami M Y, Woo Wai-Lan, Yan Mei-Kum, Choi Garnet K Y, Ho Pak-Leung, Cheng Vincent C C, Yuen Kwok-Yung
Department of Microbiology, Queen Mary Hospital, the University of Hong Kong, Hong Kong Special Administrative Region, China.
J Clin Microbiol. 2013 Dec;51(12):3981-7. doi: 10.1128/JCM.01437-13. Epub 2013 Sep 18.
Yeast and mycobacteria can cause infections in immunocompromised patients and normal hosts. The rapid identification of these organisms can significantly improve patient care. There has been an increasing number of studies on using matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) for rapid yeast and mycobacterial identifications. However, studies on direct comparisons between the Bruker Biotyper and bioMérieux Vitek MS systems for the identification of yeast and mycobacteria have been limited. This study compared the performance of the two systems in their identification of 98 yeast and 102 mycobacteria isolates. Among the 98 yeast isolates, both systems generated species-level identifications in >70% of the specimens, of which Candida albicans was the most commonly cultured species. At a genus-level identification, the Biotyper system identified more isolates than the Vitek MS system for Candida (75/78 [96.2%]versus 68/78 [87.2%], respectively; P = 0.0426) and non-Candida yeasts (18/20 [90.0%]versus 7/20 [35.0%], respectively; P = 0.0008). For mycobacterial identification, the Biotyper system generated reliable identifications for 89 (87.3%) and 64 (62.8%) clinical isolates at the genus and species levels, respectively, from solid culture media, whereas the Vitek MS system did not generate any reliable identification. The MS method differentiated 12/21 clinical species, despite the fact that no differentiation between Mycobacterium abscessus and Mycobacterium chelonae was found by using 16S rRNA gene sequencing. In summary, the MALDI-TOF MS method provides short turnaround times and a standardized working protocol for the identification of yeast and mycobacteria. Our study demonstrates that MALDI-TOF MS is suitable as a first-line test for the identification of yeast and mycobacteria in clinical laboratories.
酵母和分枝杆菌可在免疫功能低下患者及正常宿主中引起感染。快速鉴定这些微生物可显著改善患者的治疗效果。关于使用基质辅助激光解吸电离飞行时间质谱（MALDI-TOF MS）进行酵母和分枝杆菌快速鉴定的研究越来越多。然而，关于布鲁克Biotyper系统和生物梅里埃Vitek MS系统在酵母和分枝杆菌鉴定方面的直接比较研究有限。本研究比较了这两种系统对98株酵母和102株分枝杆菌分离株的鉴定性能。在98株酵母分离株中，两种系统在>70%的标本中实现了种水平鉴定，其中白色念珠菌是最常培养的菌种。在属水平鉴定中，Biotyper系统鉴定出的念珠菌分离株（分别为75/78[96.2%]和68/78[87.2%]；P = 0.0426）和非念珠菌酵母（分别为18/20[90.0%]和7/20[35.0%]；P = 0.0008）比Vitek MS系统更多。对于分枝杆菌鉴定，Biotyper系统分别从固体培养基中对89株（87.3%）和64株（62.8%）临床分离株在属和种水平上产生了可靠的鉴定结果，而Vitek MS系统未产生任何可靠的鉴定结果。尽管使用16S rRNA基因测序未发现脓肿分枝杆菌和龟分枝杆菌之间的差异，但MS方法区分了12/21种临床菌种。总之，MALDI-TOF MS方法为酵母和分枝杆菌的鉴定提供了较短的周转时间和标准化的工作流程。我们的研究表明，MALDI-TOF MS适合作为临床实验室中酵母和分枝杆菌鉴定的一线检测方法。
