1. Development and validation of a lateral flow immunoassay for rapid detection of VanA-producing enterococci.
- Author
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Oueslati S, Volland H, Cattoir V, Bernabeu S, Girlich D, Dulac D, Plaisance M, Laroche M, Dortet L, Simon S, and Naas T
- Subjects
- Bacterial Proteins genetics, Carbon-Oxygen Ligases genetics, Humans, Immunoassay, Vancomycin, Vancomycin Resistance, Enterococcus, Gram-Positive Bacterial Infections
- Abstract
Background: VRE are nosocomial pathogens with an increasing incidence in recent decades. Rapid detection is crucial to reduce their spread and prevent infections and outbreaks., Objectives: To evaluate a lateral flow immunoassay (LFIA) (called NG-Test VanA) for the rapid and reliable detection of VanA-producing VRE (VanA-VRE) from colonies and broth., Methods: NG-Test VanA was validated on 135 well-characterized enterococcal isolates grown on Mueller-Hinton (MH) agar (including 40 VanA-VRE). Different agar plates and culture broths widely used in routine laboratories for culture of enterococci were tested., Results: All 40 VanA-VRE clinical isolates were correctly detected in less than 15 min irrespective of the species expressing the VanA ligase and the medium used for bacterial growth. No cross-reaction was observed with any other clinically relevant ligases (VanB, C1, C2, D, E, G, L, M and N). Overall, the sensitivity and specificity of the assay were 100% for VanA-VRE grown on MH agar plates. NG-Test VanA accurately detects VanA-VRE irrespective of the culture medium (agar and broth). Band intensity was increased when using bacteria grown on vancomycin-containing culture media or on MH close to the vancomycin disc as a consequence of VanA induction. The limit of detection of the assay was 6.3 × 106 cfu per test with bacteria grown on MH plates and 4.9 × 105 cfu per test with bacteria grown on ChromID® VRE plates., Conclusions: NG-Test VanA is efficient, rapid and easy to implement in the routine workflow of a clinical microbiology laboratory for the confirmation of VanA-VRE., (© The Author(s) 2020. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For permissions, please email: journals.permissions@oup.com.)
- Published
- 2021
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