基质辅助激光解吸电离飞行时间质谱结合光密度比值快速检测耐头孢曲松沙门氏菌

Rapid detection of ceftriaxone-resistant Salmonella by matrix-assisted laser desorption-ionization time-of-flight mass spectrometry combined with the ratio of optical density.

作者信息

Fang Chao, Zhou Zheng, Zhou Mingming, Li Jianping

机构信息

Department of Clinical Laboratory, Children's Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, No. 3333 Binsheng road, Hangzhou, Zhejiang Province, China.

出版信息

Ann Clin Microbiol Antimicrob. 2024 Aug 7;23(1):70. doi: 10.1186/s12941-024-00729-9.

BACKGROUND

The increased resistance rate of Salmonella to third-generation cephalosporins represented by ceftriaxone (CRO) may result in the failure of the empirical use of third-generation cephalosporins for the treatment of Salmonella infection in children. The present study was conducted to evaluate a novel method for the rapid detection of CRO-resistant Salmonella (CRS).

METHODS

We introduced the concept of the ratio of optical density (ROD) with and without CRO and combined it with matrix-assisted laser desorption-ionization time-of-flight mass spectrometry (MALDI-TOF MS) to establish a new protocol for the rapid detection of CRS.

RESULTS

The optimal incubation time and CRO concentration determined by the model strain test were 2 h and 8 µg/ml, respectively. We then conducted confirmatory tests on 120 clinical strains. According to the receiver operating characteristic curve analysis, the ROD cutoff value for distinguishing CRS and non-CRS strains was 0.818 [area under the curve: 1.000; 95% confidence interval: 0.970-1.000; sensitivity: 100.00%; specificity: 100%; P < 10].

CONCLUSIONS

In conclusion, the protocol for the combined ROD and MALDI-TOF MS represents a rapid, accurate, and economical method for the detection of CRS.

背景

以头孢曲松（CRO）为代表的沙门氏菌对第三代头孢菌素的耐药率上升，可能导致经验性使用第三代头孢菌素治疗儿童沙门氏菌感染失败。本研究旨在评估一种快速检测耐头孢曲松沙门氏菌（CRS）的新方法。

方法

我们引入了加与不加CRO时的光密度比值（ROD）的概念，并将其与基质辅助激光解吸电离飞行时间质谱（MALDI-TOF MS）相结合，建立了一种快速检测CRS的新方案。

结果

通过模式菌株试验确定的最佳孵育时间和CRO浓度分别为2小时和8μg/ml。然后我们对120株临床菌株进行了验证试验。根据受试者工作特征曲线分析，区分CRS和非CRS菌株的ROD临界值为0.818[曲线下面积：1.000；95%置信区间：0.970-1.000；灵敏度：100.00%；特异性：100%；P < 0.001]。