Original Title: Détection de l’entérocoque résistant à la vancomycine (ERV)

Authors' objectives: Since November 2003, Quebec facilities have been required to report outbreaks of vancomycin-resistant enterococci (VRE). In 2012, the Comité sur les infections nosocomiales du Québec (CINQ) issued recommendations aimed at preventing the transmission of VRE, including early detection of at-risk cases as soon as they are admitted to the hospital to ensure preventive isolation. The use of nucleic acid amplification tests (NAATs) and culture on chromogenic agar is recommended, without specifying which should be preferred. Given the high volume of tests for VRE in Quebec, and the heterogeneity of the methods used, the Ministère de la Santé et des Services sociaux (MSSS) commissioned the Institut national d'excellence en santé et en services sociaux (INESSS) to determine the most efficient strategy for identifying people colonized by VRE.

Authors' results and conclusions: RESULTS : According to the scientific literature, prolonged incubation of chromogenic agars to detect VRE improves sensitivity and negative predictive value, but reduces specificity and positive predictive value. Indeed, over time, non-specific bacterial growth can generate false-positive results. A pre-culture enrichment step would also increase sensitivity, but at the cost of reduced specificity. In general, NAAT kits show a low positive predictive value for the vanB gene, which can be explained by the fact that it is not very prevalent. The guidelines identified do not favor any particular VRE detection method. Clinicians consulted favor VRE detection by NAAT in facilities where preventive isolation is not possible, because of the shorter response time and to limit the risk of transmission. In other facilities, chromogenic agar culture is used in conjunction with preventive isolation. The clinicians consulted stressed the importance of using a detection strategy that minimizes the duration of isolation. CONCLUSION : In conclusion, INESSS suggests that NAAT be preferred to chromogenic agar for VRE testing of patients at risk of colonization when placed in preventive isolation. In a context where private rooms are in short supply, detection by NAAT is the least expensive approach, provided that the response time of the detection test is kept to a minimum. In certain circumstances, chromogenic agar, or a combination of the two methods, may be preferred due to local considerations.

Project Status: Completed

URL for project: https://www.inesss.qc.ca/publications/repertoire-des-publications/publication/detection-de-lenterocoque-resistant-a-la-vancomycine-erv.html

Year Published: 2025

URL for published report: https://www.inesss.qc.ca/publications/repertoire-des-publications/publication/detection-de-lenterocoque-resistant-a-la-vancomycine-erv.html

English language abstract: An English language summary is available

Publication Type: Other

Country: Canada

Province: Quebec

Organisation Name: Institut national d'excellence en sante et en services sociaux

Contact Address: L'Institut national d'excellence en sante et en services sociaux (INESSS) , 2021, avenue Union, bureau 10.083, Montreal, Quebec, Canada, H3A 2S9;Tel: 1+514-873-2563, Fax: 1+514-873-1369

Contact Name: demande@inesss.qc.ca

Contact Email: demande@inesss.qc.ca

Copyright: L'Institut national d'excellence en sante et en services sociaux (INESSS)