Performance of commercial methods for linezolid susceptibility testing of Enterococcus faecium and Enterococcus faecalis

Autor: Ronan Le Guen, Vincent Cattoir, V. Fihman, Hervé Jacquier, Gauthier Péan de Ponfilly, Loren Dejoies, Sophie Potrel, Anaïs Collet, Sarrah Boukthir, Laurent Dortet, Gabriel Auger, Asma Zouari
Přispěvatelé: CHU Pontchaillou [Rennes], ARN régulateurs bactériens et médecine (BRM), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Structure Fédérative de Recherche en Biologie et Santé de Rennes ( Biosit : Biologie - Santé - Innovation Technologique ), Hôpital Lariboisière-Fernand-Widal [APHP], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP), Dynamic Microbiology - EA 7380 (DYNAMIC), École nationale vétérinaire d'Alfort (ENVA)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12), Santé Publique France, French National Public Health Agency, Université de Rennes (UR)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Structure Fédérative de Recherche en Biologie et Santé de Rennes ( Biosit : Biologie - Santé - Innovation Technologique ), École nationale vétérinaire - Alfort (ENVA)-Agence nationale de sécurité sanitaire de l'alimentation, de l'environnement et du travail (ANSES)-Université Paris-Est (UPE)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)
Rok vydání: 2020
Předmět:
Zdroj: Journal of Antimicrobial Chemotherapy
Journal of Antimicrobial Chemotherapy, Oxford University Press (OUP), 2020, 75 (9), pp.2587-2593. ⟨10.1093/jac/dkaa180⟩
Journal of Antimicrobial Chemotherapy, 2020, 75 (9), pp.2587-2593. ⟨10.1093/jac/dkaa180⟩
ISSN: 1460-2091
0305-7453
DOI: 10.1093/jac/dkaa180
Popis: Background Linezolid-resistant enterococci (LRE) causing infections that are challenging to treat are rising, highlighting the need for reliable screening of LRE clinical isolates. Objectives To evaluate the ability of the broth microdilution (BMD) method for LRE detection and to assess the performance of seven commercially available techniques for linezolid susceptibility testing. Methods A collection of 100 clinical isolates (80 Enterococcus faecium and 20 Enterococcus faecalis), including 20 optrA-positive isolates, 17 poxtA-positive isolates and 1 optrA/poxtA-positive E. faecium isolate, were studied. MICs were determined after 18 h [Day 1 (D1)] and 42 h [Day 2 (D2)] of incubation and interpreted following EUCAST and CLSI guidelines, which currently provide different interpretative breakpoints. Performance of commercial techniques was compared with BMD results. Results MIC50/D1 and MIC50/D2 were both 8 mg/L, while MIC90/D1 and MIC90/D2 were 16 and 32 mg/L, respectively. MICD1 values for poxtA-positive isolates were lower than those for optrA-positive isolates. Proportions of susceptible isolates at D1 and D2 were 48% and 41%, respectively, according to EUCAST breakpoints and 35% and 13%, respectively, according to CLSI criteria (the proportions of isolates categorized as intermediate following CLSI recommendations were 13% and 28% at D1 and D2, respectively). Percentage susceptibility assessed by the commercially available techniques was always higher. The four commercial methods allowing MIC determination provided an overall essential agreement of ≥90% at D1. Categorical agreement and error rates were generally improved at D2. Conclusions Non-automated methods (Sensititre and UMIC) and, to a lesser extent, gradient strip Etest appear to show an acceptable correlation with the BMD reference method for the detection of isolates with low MICs of linezolid after prolonged incubation.
Databáze: OpenAIRE
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