Laurent Dortet1,2,3,4, Remy A Bonnin3,4, Ivana Pennisi1, Lauraine Gauthier2,3,4, Agnès B Jousset2,3,4, Laura Dabos5, R Christopher D Furniss1, Despoina A I Mavridou1, Pierre Bogaerts6, Youri Glupczynski6, Anais Potron4,7, Patrick Plesiat4,7, Racha Beyrouthy4,8, Frédéric Robin4,8, Richard Bonnet4,8, Thierry Naas2,3,4, Alain Filloux1, Gerald Larrouy-Maumus1. 1. MRC Centre for Molecular Bacteriology and Infection, Department of Life Sciences, Faculty of Natural Sciences, Imperial College London, London, UK. 2. Department of Bacteriology-Hygiene, Bicêtre Hospital, Assistance Publique - Hôpitaux de Paris, Le Kremlin-Bicêtre, France. 3. EA7361 'Structure, dynamic, function and expression of broad spectrum β-lactamases', Paris-Sud University, Paris Saclay University, LabEx Lermit, Faculty of Medicine, Le Kremlin-Bicêtre, France. 4. French National Reference Center for Antibiotic Resistance, Le Kremlin-Bicêtre, France. 5. EA7361 'Structure, dynamic, function and expression of broad spectrum ß-lactamases', Paris-Sud University, Paris Saclay University, LabEx Lermit, Faculty of Medicine, Le Kremlin-Bicêtre, France. 6. Laboratory of Clinical Microbiology, Belgian National Reference Center for Monitoring Antimicrobial Resistance in Gram-negative Bacteria, CHU UCL Namur, Yvoir, Belgium. 7. Bacteriology Unit, University Hospital of Besançon, Besançon, France. 8. Bacteriology Unit, University Hospital of Clermont-Ferrand, Clermont-Ferrand, France.
Abstract
Background: Polymyxins are currently considered a last-resort treatment for infections caused by MDR Gram-negative bacteria. Recently, the emergence of carbapenemase-producing Enterobacteriaceae has accelerated the use of polymyxins in the clinic, resulting in an increase in polymyxin-resistant bacteria. Polymyxin resistance arises through modification of lipid A, such as the addition of phosphoethanolamine (pETN). The underlying mechanisms involve numerous chromosome-encoded genes or, more worryingly, a plasmid-encoded pETN transferase named MCR. Currently, detection of polymyxin resistance is difficult and time consuming. Objectives: To develop a rapid diagnostic test that can identify polymyxin resistance and at the same time differentiate between chromosome- and plasmid-encoded resistances. Methods: We developed a MALDI-TOF MS-based method, named the MALDIxin test, which allows the detection of polymyxin resistance-related modifications to lipid A (i.e. pETN addition), on intact bacteria, in <15 min. Results: Using a characterized collection of polymyxin-susceptible and -resistant Escherichia coli, we demonstrated that our method is able to identify polymyxin-resistant isolates in 15 min whilst simultaneously discriminating between chromosome- and plasmid-encoded resistance. We validated the MALDIxin test on different media, using fresh and aged colonies and show that it successfully detects all MCR-1 producers in a blindly analysed set of carbapenemase-producing E. coli strains. Conclusions: The MALDIxin test is an accurate, rapid, cost-effective and scalable method that represents a major advance in the diagnosis of polymyxin resistance by directly assessing lipid A modifications in intact bacteria.
Background: Polymyxins are currently considered a last-resort treatment for infections caused by MDR Gram-negative bacteria. Recently, the emergence of carbapenemase-producing Enterobacteriaceae has accelerated the use of polymyxins in the clinic, resulting in an increase in polymyxin-resistant bacteria. Polymyxin resistance arises through modification of lipid A, such as the addition of phosphoethanolamine (pETN). The underlying mechanisms involve numerous chromosome-encoded genes or, more worryingly, a plasmid-encoded pETN transferase named MCR. Currently, detection of polymyxin resistance is difficult and time consuming. Objectives: To develop a rapid diagnostic test that can identify polymyxin resistance and at the same time differentiate between chromosome- and plasmid-encoded resistances. Methods: We developed a MALDI-TOF MS-based method, named the MALDIxin test, which allows the detection of polymyxin resistance-related modifications to lipid A (i.e. pETN addition), on intact bacteria, in <15 min. Results: Using a characterized collection of polymyxin-susceptible and -resistant Escherichia coli, we demonstrated that our method is able to identify polymyxin-resistant isolates in 15 min whilst simultaneously discriminating between chromosome- and plasmid-encoded resistance. We validated the MALDIxin test on different media, using fresh and aged colonies and show that it successfully detects all MCR-1 producers in a blindly analysed set of carbapenemase-producing E. coli strains. Conclusions: The MALDIxin test is an accurate, rapid, cost-effective and scalable method that represents a major advance in the diagnosis of polymyxin resistance by directly assessing lipid A modifications in intact bacteria.
Authors: R Christopher D Furniss; Nikol Kaderabkova; Declan Barker; Patricia Bernal; Evgenia Maslova; Amanda A A Antwi; Helen E McNeil; Hannah L Pugh; Laurent Dortet; Jessica M A Blair; Gerald Larrouy-Maumus; Ronan R McCarthy; Diego Gonzalez; Despoina A I Mavridou Journal: Elife Date: 2022-01-13 Impact factor: 8.713
Authors: Laurent Dortet; Rémy A Bonnin; Simon Le Hello; Laetitia Fabre; Richard Bonnet; Markus Kostrzewa; Alain Filloux; Gerald Larrouy-Maumus Journal: Front Microbiol Date: 2020-06-03 Impact factor: 5.640
Authors: R Christopher D Furniss; Laurent Dortet; William Bolland; Oliver Drews; Katrin Sparbier; Rémy A Bonnin; Alain Filloux; Markus Kostrzewa; Despoina A I Mavridou; Gerald Larrouy-Maumus Journal: J Clin Microbiol Date: 2019-11-22 Impact factor: 5.948