1株致脓毒症融合魏斯氏菌的鉴定

Identification of a sepsis-causing strain of Weissella confusa

目的对一株从脓毒症患者血液中分离到的融合魏斯氏菌进行鉴定。方法无菌条件下经肘静脉取患者血液进行细菌分离培养,观察血液中细菌的形态特征,并进行生化实验、MALDI-TOF MS鉴定实验、16s rRNA分析及药物敏感性试验。结果细菌经分离后初步鉴定为魏斯氏菌属,经MALDI-TOF MS鉴定该菌为融合魏斯氏菌,置信度为99.9%;16S rRNA扩增产物测序后经BLAST分析,置信度为99.9%;该菌对庆大霉素、环丙沙星、左氧氟沙星等常见抗菌药物均敏感,但对万古霉素、利福平存在天然耐药。结论经实验鉴定该菌株为融合魏斯氏菌,后续将对其致脓毒症的相关机制进行研究。

OBJECTIVE To identify a strain of Weissella confusa isolated from the blood of a patient with sepsis.METHODS Under aseptic conditions,the patient′s blood was extracted through elbow vein for bacterial isolation and culture,the morphological characteristics of bacteria in blood were observed,and biochemical tests,MALDI-TOF MS identification test,16s rRNA analysis and drug sensitivity test were performed.RESULTS The bacteria were initially identified as Weissella spp.after isolation,and identified as Weissella confusa by MALDI-TOF MS,with a confidence coefficient of 99.9%.The 16S rRNA amplification products were sequenced and analyzed by blast,with a confidence coefficient of 99.9%.The bacterium was sensitive to common antimicrobial drugs such as gentamicin,ciprofloxacin,levofloxacin et al,but was naturally resistant to vancomycin and rifampicin.CONCLUSION This strain was experimentally identified as Weissella confusa,and its mechanism involved in its sepsis-causing effects would be investigated subsequently.