Use of matrix-assisted laser desorption ionization-time of flight mass spectrometry to identify MLST clade 4 Clostridium difficile isolates

Clostridium difficile is the leading cause of health care-associated infections. Previous studies suggest that C. difficile MLST clade 4 strains with higher drug resistance rates constitute the major clone spreading in China. Thus development of a rapid and accurate typing method for these strains is needed to monitor the epidemiology of this clone and to guide clinical treatment A total of 160 non-duplicate C. difficile isolates recovered from three large teaching hospitals in Beijing were studied. All the 41 clade 4 C. difficile isolates clustered together on the PCA dendrogram. Spectra peak statistics revealed that five markers (2691.43Da, 2704.91Da, 2711.93Da, 3247.27Da and 3290.76Da) can easily and reliably distinguish between clade 4 and non-clade 4 isolates, with area under the curve (AUC) values of 0.991, 0.997, 0.973,1 and 1, respectively. In conclusion, MALDI-TOF MS is a very simple and accurate method for identifying C. difficile MLST clade 4 strains. (C) 2018 Elsevier Inc. All rights reserved.

艰难梭菌是医疗保健相关感染的首要原因。先前的研究表明，具有较高耐药率的艰难梭菌多位点序列分型（MLST）第4分支菌株是在中国传播的主要克隆。因此，需要为这些菌株开发一种快速且准确的分型方法，以监测该克隆的流行病学并指导临床治疗。对从北京三家大型教学医院收集的共160株不重复的艰难梭菌分离株进行了研究。所有41株第4分支艰难梭菌分离株在主成分分析（PCA）树状图上聚在一起。光谱峰统计显示，五个标记物（2691.43道尔顿、2704.91道尔顿、2711.93道尔顿、3247.27道尔顿和3290.76道尔顿）能够轻松且可靠地区分第4分支和非第4分支分离株，曲线下面积（AUC）值分别为0.991、0.997、0.973、1和1。总之，基质辅助激光解吸电离飞行时间质谱（MALDI - TOF MS）是一种非常简单且准确的鉴定艰难梭菌MLST第4分支菌株的方法。（C）2018爱思唯尔公司。保留所有权利。