Assistance Publique-Hôpitaux de Paris, Laboratoire de Microbiologie, Hôpital Necker-Enfants Malades, 149 rue de Sèvres, Paris, France.
Clin Microbiol Infect. 2012 Nov;18(11):1117-25. doi: 10.1111/j.1469-0691.2011.03688.x. Epub 2011 Nov 1.
All organisms usually isolated in our laboratory are now routinely identified by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) using the Andromas software. The aim of this study was to describe the use of this strategy in a routine clinical microbiology laboratory. The microorganisms identified included bacteria, mycobacteria, yeasts and Aspergillus spp. isolated on solid media or extracted directly from blood cultures. MALDI-TOF MS was performed on 2665 bacteria isolated on solid media, corresponding to all bacteria isolated during this period except Escherichia coli grown on chromogenic media. All acquisitions were performed without extraction. After a single acquisition, 93.1% of bacteria grown on solid media were correctly identified. When the first acquisition was not contributory, a second acquisition was performed either the same day or the next day. After two acquisitions, the rate of bacteria identified increased to 99.2%. The failures reported on 21 strains were due to an unknown profile attributed to new species (9) or an insufficient quality of the spectrum (12). MALDI-TOF MS has been applied to 162 positive blood cultures. The identification rate was 91.4%. All mycobacteria isolated during this period (22) were correctly identified by MALDI-TOF MS without any extraction. For 96.3% and 92.2% of yeasts and Aspergillus spp., respectively, the identification was obtained with a single acquisition. After a second acquisition, the overall identification rate was 98.8% for yeasts (160/162) and 98.4% (63/64) for Aspergillus spp. In conclusion, the MALDI-TOF MS strategy used in this work allows a rapid and efficient identification of all microorganisms isolated routinely.
所有在我们实验室中分离得到的生物体现在通常都通过基质辅助激光解吸电离飞行时间质谱（MALDI-TOF MS）和 Andromas 软件进行常规鉴定。本研究的目的是描述在常规临床微生物学实验室中使用这种策略的情况。鉴定的微生物包括细菌、分枝杆菌、酵母和曲霉菌属，它们是从固体培养基上分离得到的，或者是直接从血液培养物中提取得到的。对 2665 株在固体培养基上分离得到的细菌进行了 MALDI-TOF MS 分析，这些细菌涵盖了在此期间除了在显色培养基上生长的大肠杆菌之外所有分离得到的细菌。所有的获取均无需提取。经过单次获取，93.1%在固体培养基上生长的细菌得到了正确鉴定。如果首次获取没有贡献，则在同一天或次日进行第二次获取。经过两次获取，细菌的鉴定率提高到 99.2%。21 株报告的失败是由于未知的新物种（9 株）或谱图质量不足（12 株）导致的未知图谱。MALDI-TOF MS 已经应用于 162 例阳性血培养物。鉴定率为 91.4%。在此期间分离得到的所有分枝杆菌（22 株）都无需提取就通过 MALDI-TOF MS 得到了正确鉴定。对于 96.3%和 92.2%的酵母和曲霉菌属，分别通过单次获取就得到了鉴定结果。经过第二次获取，酵母的总体鉴定率为 98.8%（160/162），曲霉菌属为 98.4%（63/64）。总之，本工作中使用的 MALDI-TOF MS 策略可以快速有效地鉴定所有常规分离得到的微生物。
