AUTHOR=Foglietta Gianluca , De Carolis Elena , Mattana Giordana , Onori Manuela , Agosta Marilena , Niccolai Claudia , Di Pilato Vincenzo , Rossolini Gian Maria , Sanguinetti Maurizio , Perno Carlo Federico , Bernaschi Paola 

TITLE=“CORE” a new assay for rapid identification of Klebsiella pneumoniae COlistin REsistant strains by MALDI-TOF MS in positive-ion mode

JOURNAL=Frontiers in Microbiology

VOLUME=14

YEAR=2023

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2023.1045289

DOI=10.3389/fmicb.2023.1045289

ISSN=1664-302X

ABSTRACT=<p>Due to the global spread of pan resistant organisms, colistin is actually considered as one of the last resort antibiotics against MDR and XDR bacterial infections. The emergence of colistin resistant strains has been observed worldwide in Gram-negative bacteria, such as <italic>Enterobacteriaceae</italic> and especially in <italic>K. pneumoniae,</italic> in association with increased morbidity and mortality. This landscape implies the exploration of novel assays able to target colistin resistant strains rapidly.</p><p>In this study, we developed and evaluated a new MALDI-TOF MS assay in positive-ion mode that allows quantitative or qualitative discrimination between colistin susceptible (18) or resistant (32) <italic>K. pneumoniae</italic> strains in 3 h by using the “Autof MS 1000” mass spectrometer. The proposed assay, if integrated in the diagnostic workflow, may be of help for the antimicrobial stewardship and the control of the spread of <italic>K. pneumoniae</italic> colistin resistant isolates in hospital settings.</p>