应用基质辅助激光解析电离飞行时间质谱鉴定常见细菌和酵母菌

Identification of bacteria and fungi by matrix-assisted laser desorption ionization-time of flight mass spectrometry

目的应用MALDI—TOFMS鉴定临床常见病原菌。方法复苏560株临床分离株，其中革兰阳性细菌（G^＋）260株、革兰阴性细菌（G^-）180株、酵母菌60株、肠道致病菌60株。MALDI—TOFMS鉴定结果与Vitek2Compact全白动微生物鉴定系统比对，结果差异菌株采用16SrDNA测序验证。结果MALDI—TOFMS与Vitek2Compact鉴定结果比较，G^＋细菌鉴定符合率为94．6％（246／260），G^-细菌鉴定符合率为96．7％（174／180），酵母菌鉴定符合率为95．0％（57／60），肠道致病菌鉴定符合率为93．3％（56／60）。15株鉴定结果不符的菌株经16SrDNA测序确认，结果与Vitek2Compact和MALDI—TOFMS鉴定符合率分别为26．7％（4／15）和66．7％（10／15）。结论MALDI—TOFMS可用于常见病原微生物鉴定，其快速、低成本的特点具有推广价值。

Objective To identify the pathogenic microorganism by MALDI-TOF MS. Methods A total of 560 strains were resuscitated, which included 260 gram-positive bacteria strains, 180 gram-negative bacteria strains, 60 yeast-like-fungi strains and 60 enteropathogenic bacteria strains. Comparing MALDI-TOF MS with Vitek2 Compact, the discordant resuhs were validated by 16S rDNA sequencing. Results Comparing MALDI-TOF MS with Vitek2 Compact, the coincidence rate was 94. 6% （246/260） for gram-positive bacteria, 96.7% （174/180） for gram-negative bacteria,95% （57/60） for yeast-like-fungi, and 93.3% （56/60） for enteropathogenic bacteria. Fifteen strains were validated by 16S rDNA gene sequencing. Comparing with sequencing, the coincidence rate of two methods was 66. 7% （10/15） for MALDI-TOF MS and 26. 7% （4/11） for Vitek2 Compact, respectively. Conclusion MALDI-TOF MS shows rapid turnaround time and modest reagent costs, and it will be another effective tool for microorganism diagnosis.