title: Rapid Detection of Polymyxin Resistance in Enterobacteriaceae.
abstract: For identification of polymyxin resistance in Enterobacteriaceae, we developed a rapid test that detects glucose metabolization associated with bacterial growth in the presence of a defined concentration of colistin or polymyxin B. Formation of acid metabolites is evidenced by a color change (orange to yellow) of a pH indicator (red phenol). To evaluate the test, we used bacterial colonies of 135 isolates expressing various mechanisms of colistin resistance (intrinsic, chromosomally encoded, and plasmid-mediated MCR-1) and 65 colistin-susceptible isolates. Sensitivity and specificity were 99.3% and 95.4%, respectively, compared with the standard broth microdilution method. This new test is inexpensive, easy to perform, sensitive, specific, and can be completed in <2 hours. It could be useful in countries facing endemic spread of carbapenemase producers and for which polymyxins are last-resort drugs.
authors.forename: Patrice
authors.initials: P
authors.lastname: Nordmann
authors.forename: Aurélie
authors.initials: A
authors.lastname: Jayol
authors.forename: Laurent
authors.initials: L
authors.lastname: Poirel
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D024881:Drug Resistance, Bacterial; D004755:Enterobacteriaceae / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification; D004756:Enterobacteriaceae Infections / Q000175:diagnosis* / Q000382:microbiology*; D005798:Genes, Bacterial; D005838:Genotype; D006801:Humans; D008826:Microbial Sensitivity Tests; D011113:Polymyxins / Q000494:pharmacology*
chemical_list: D000900:Anti-Bacterial Agents; D011113:Polymyxins
keywords: Enterobacteriaceae; MCR-1; antibiotic; antimicrobial resistance; colistin; polymyxin B; rapid diagnostic test; resistance; susceptibility testing