title: Prospective evaluation of the OKN K-SeT assay, a new multiplex immunochromatographic test for the rapid detection of OXA-48-like, KPC and NDM carbapenemases.
abstract: There is an urgent need for accurate and fast diagnostic tests capable of identifying carbapenemase producers. Here, we assessed the performance of a new multiplex lateral flow assay (OKN K -SeT) for the rapid detection of OXA-48-like, KPC and NDM carbapenemase-producing Enterobacteriaceae from culture colonies.
  
  
  
  Two hundred collection isolates with characterized β-lactamase content and 183 non-duplicate consecutive isolates referred to two National Reference Centres over a 2 month period in 2016 were used to evaluate the OKN K -SeT assay.
  
  
  
  The assay correctly detected all 42 OXA-48-like-, 27 KPC- and 30 NDM-producing isolates from the collection panel, including 7 isolates that co-produced NDM and OXA-181 carbapenemases. No cross-reactivity was observed with non-targeted carbapenemases ( n  =   41) or with non-carbapenemase producers ( n  =   60). Prospectively, all OXA-48-like ( n  =   69), KPC ( n  =   9) and NDM ( n  =   19) carbapenemase-producing Enterobacteriaceae isolates were correctly detected, while 11 carbapenemase producers not targeted by the assay went undetected [VIM ( n  =   8) and OXA-23/OXA-58-like ( n  =   3)]. Overall, the sensitivity and specificity of the assay were 100%.
  
  
  
  The OKN assay is efficient, rapid and easy to implement in the workflow of a clinical microbiology laboratory for the confirmation of OXA-48, NDM and KPC carbapenemases. This test represents a powerful diagnostic tool as it enables the rapid detection of the most clinically important carbapenemases without the need for more costly and less frequently available molecular assays.
authors.affiliation: Laboratory of Clinical Microbiology, National Reference Centre for Monitoring Antimicrobial Resistance in Gram-Negative Bacteria, CHU UCL Namur, Yvoir, Belgium.
authors.forename: Youri
authors.initials: Y
authors.lastname: Glupczynski
authors.forename: Agnès
authors.initials: A
authors.lastname: Jousset
authors.affiliation: Laboratory of Clinical Microbiology, National Reference Centre for Monitoring Antimicrobial Resistance in Gram-Negative Bacteria, CHU UCL Namur, Yvoir, Belgium.
authors.forename: Stéphanie
authors.initials: S
authors.lastname: Evrard
authors.forename: Rémy A
authors.initials: RA
authors.lastname: Bonnin
authors.affiliation: Laboratory of Clinical Microbiology, National Reference Centre for Monitoring Antimicrobial Resistance in Gram-Negative Bacteria, CHU UCL Namur, Yvoir, Belgium.
authors.forename: Te-Din
authors.initials: TD
authors.lastname: Huang
authors.forename: Laurent
authors.initials: L
authors.lastname: Dortet
authors.affiliation: Laboratory of Clinical Microbiology, National Reference Centre for Monitoring Antimicrobial Resistance in Gram-Negative Bacteria, CHU UCL Namur, Yvoir, Belgium.
authors.forename: Pierre
authors.initials: P
authors.lastname: Bogaerts
authors.forename: Thierry
authors.initials: T
authors.lastname: Naas
mesh_terms: D001426:Bacterial Proteins / Q000032:analysis / Q000096:biosynthesis* / Q000276:immunology; D001431:Bacteriological Techniques; D000073182:Carbapenem-Resistant Enterobacteriaceae / Q000201:enzymology / Q000276:immunology / Q000302:isolation & purification* / Q000378:metabolism; D002846:Chromatography, Affinity / Q000379:methods*; D004756:Enterobacteriaceae Infections / Q000175:diagnosis* / Q000382:microbiology; D006801:Humans; D008826:Microbial Sensitivity Tests; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D001618:beta-Lactamases / Q000032:analysis / Q000096:biosynthesis* / Q000276:immunology
chemical_list: D001426:Bacterial Proteins; D001618:beta-Lactamases; C063912:carbapenemase