Abstract
In this study, we evaluate the performance of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) for rapid detection of carbapenemase activity in Enterobacterales in clinical microbiology laboratories during a multicenter networking validation study. The study was divided into three different stages: “software design,” “intercenter evaluation,” and “clinical validation.” First, a standardized procedure with an online software for data analysis was designed. Carbapenem resistance was detected by measuring imipenem hydrolysis and the results were automatically interpreted using the Clover MS data analysis software (Clover BioSoft, Spain). Second, a series of 74 genotypically characterized Enterobacterales (46 carbapenemase-producers and 28 non carbapenemase-producers) were analyzed in 8 international centers to ensure the reproducibility of the method. Finally, the methodology was evaluated independently in all centers during a 2-month period and results were compared with the reference standard for carbapenemase detection used in each center. The overall agreement rate relative to the reference method for carbapenemase resistance detection in clinical samples was 92.5%. The sensitivity was 93.9% and the specificity, 100%. Results were obtained within 60 min and accuracy ranged from 83.3 to 100% among the different centers. Further, our results demonstrate that MALDI-TOF MS is an outstanding tool for rapid detection of carbapenemase activity in Enterobacterales in clinical microbiology laboratories. The use of a simple in-house procedure with online software allows routine screening of carbapenemases in diagnostics, thereby facilitating early and appropriate antimicrobial therapy.
Highlights
Carbapenemase-producing Enterobacterales (CPE) have been recognized by a number of national and international health organizations to represent a major threat to global health (Rodríguez-Baño et al, 2018; U.S Centers for Disease Control and Prevention, 2019; European Center for Disease Prevention and Control, 2020)
In the Clover MS data analysis software (Clover BioSoft), the ratio of hydrolysis (RH) was calculated in two different ways: (b) by using the intensity of the imipenem mass peaks and (c) by using the area under the curve (AUC) of the peaks
A receiver operating characteristic (ROC) curve was calculated for the three methods, yielding AUC values of (a) 0.977 (0.939–1), (b) 0.994 (0.985–1), and (c) 0.990 (0.976–1), with a 95% confidence interval
Summary
Carbapenemase-producing Enterobacterales (CPE) have been recognized by a number of national and international health organizations to represent a major threat to global health (Rodríguez-Baño et al, 2018; U.S Centers for Disease Control and Prevention, 2019; European Center for Disease Prevention and Control, 2020). Lateral flow and DNA-based methods have been used in the laboratory with the aim of detecting CPE (Hrabák et al, 2014). Since the introduction of MALDI-TOF in clinical microbiology laboratories, approaches to detect carbapenemases have been made by using MALDI-TOF MS-based measurement of the hydrolysis of different antibiotics (Clark et al, 2013; Papagiannitsis et al, 2015; Oviaño and Bou, 2018; Oviaño et al, 2019). Standardization of the methodology is required before universal application of MALDI-TOF for the detection of carbapenemase activity based on hydrolysis of a carbapenem antibiotic
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
