应用基质辅助激光解吸电离飞行时间质谱技术鉴定临床常见厌氧菌

目的：应用基质辅助激光解吸电离飞行时间质谱（MALDI-TOF MS）技术对临床分离的厌氧菌进行鉴定，与传统Vitek32 ANI鉴定卡及16 S rRNA基因序列法鉴定进行比较，分析MALDI-TOF MS技术用于鉴定临床常见厌氧菌的可行性。方法收集从临床标本培养分离的厌氧菌56株，运用 MALDI-TOF MS 技术对其进行鉴定，同时运用 Vitke32 ANI 鉴定卡及16 S rRNA基因序列法分别进行鉴定，将三者的结果进行比较。结果56株厌氧菌中有41株采用 MALDI-TOF MS技术鉴定至种的水平（分值大于或等于2．0），11株鉴定至属的水平（分值为1．7～2．0），4株无可靠结果（分值小于1．7）。MALDI-TOF MS和16S rRNA基因序列法鉴定结果一致的占94．6％（53/56），不一致的占5．6％（3/56）。MALDI-TOF MS与Vitke32 ANI 鉴定卡的鉴定结果一致的占80．4％（45/56），不一致的占19．6％（11/56）。结论 MALDI-TOF MS与16S rRNA基因序列法鉴定的符合率高，可应用于临床常见厌氧菌的鉴定。

Identification of anaerobic bacteria from clinical specimens by MALDI-TOF MS

Objective To evaluate whether matrix-assisted laser desorption ionization-time of flight mass spectrometry （MAL- DI-TOF MS） could be used to identify the clinical anaerobic isolates,we compared the method of MALDI-TOF MS with the con- ventional method of Vitek32 ANI card and that of 16S rRNA gene sequencing. Methods We identified 56 clinical anaerobic isolates from Beijing Tongren hospital by MALDI-TOF MS,Vitke32 ANI card and 16S rRNA gene sequencing. Then we compared these i- dentification results of MALDI-TOF MS with those of Vitke32 ANI card and those of 16S rRNA gene sequencing, respectively. Re- sults MALDI-TOF MS identified 41 of 56 isolates （73.2%） at species level （log score≥2.0） and llof those （19.6%） at genus level（log score= 1.7- 2.0）, while 4 of those（7.1 %） were given non-reliable identification（log scored 1.7）. 53 isolates（94.6 % ） of these results were consistent with those of 16S rRNA gene sequencing,though only 45 of 56 isolates （80.4 G ） are the same identifi- cation of Vitek32 ANI card. Conclusion These results showed that MALDI-TOF MS could correctly identify the clinical anaerobic isolates more than the conventional method of Vitek32 ANI card,so MALDI-TOF MS could be applied to the routine identification of clinical anaerobic bacteria.