Rapid diagnostic of multidrug-resistant sepsis pathogens directly from blood culture bottles using MALDI-TOF and the EUCAST RAST

• Published in: Diagnostic microbiology and infectious disease Vol. 109; no. 2; p. 116247
• Main Authors: Pariona, Jesus G.M., Oliveira, Flavio A., Scoton, Patrícia Helena, Barrón-Pastor, Heli J., Pariona, Eva M.M., Zaccariotto, Tania R., Lincopan, Nilton, Levy, Carlos E.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01-06-2024
• Subjects: Anti-Bacterial Agents - pharmacology; Antimicrobial susceptibility testing; Bacteria - classification; Bacteria - drug effects; Bacteria - isolation & purification; Bacterial Proteins; beta-Lactamases; Blood culture; Blood Culture - methods; Carbapenemases; Critical priority pathogens; Drug Resistance, Multiple, Bacterial; Enterobacterales; Humans; Microbial Sensitivity Tests - methods; Multidrug resistance; Rapid Diagnostic Tests; RAST; Sensitivity and Specificity; Sepsis - diagnosis; Sepsis - microbiology; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization - methods; Time Factors; Enterobacterales; Multidrug resistance; RAST; Carbapenemases; Antimicrobial susceptibility testing; Critical priority pathogens; Blood culture
• ISSN: 0732-8893; 1879-0070; 1879-0070
• DOI: 10.1016/j.diagmicrobio.2024.116247

In this study, rapid diagnostic of multidrug-resistant (MDR) sepsis pathogens, directly from positive blood culture (BC) bottles, was evaluated by combining MALDI-TOF and the EUCAST Rapid Antimicrobial Susceptibility Testing (RAST). Carbapenemase production in Escherichia coli and Klebsiella pneumoniae isolates was also evaluated by RAST. From 171 positive BC bottles analyzed, 79 (46 %) MDR species, including E. coli (4/34, 12 %), K. pneumoniae (33/48, 69 %), Pseudomonas aeruginosa (12/12, 100 %), Acinetobacter baumannii (15/15, 100 %), and Staphylococcus aureus (14/37, 38 %) displaying resistance to beta-lactams, fluoroquinolones, aminoglycosides, and/or trimethoprim/sulphamethoxazole, were identified. In this regard, turnaround time of direct MALDI-TOF identification and RAST was < 7 h, which was significantly (p< 0.05) lower than our routine method. Carbapenemase detection by RAST displayed 100% sensitivity and 88.7 % specificity at 8 h. This protocol could offer advantages for the treatment and clinical outcomes of septic patients, improving the rapid diagnostic of sepsis by MDR pathogens.