Investigation of the introduction and dissemination of vanB Enterococcus faecium in the Capital Region of Denmark and development of a rapid and accurate clone-specific vanB E. faecium PCR. (21st June 2021)

• Record Type: Journal Article
• Authors: Pinholt, Mette; Mollerup, Sarah; Boye, Kit; Worning, Peder; Holzknecht, Barbara Juliane; Nygaard, Sanne; Nielsen, Karen Leth; Hasman, Henrik; Roer, Louise; Hammerum, Anette M.; Westh, Henrik; Schønning, Kristian
• Is Part Of: Journal of antimicrobial chemotherapy. Volume 76:Number 9(2021)
• Page Start: 2260
• Page End: 2267
• Publication Date: 2021-06-21
• Subjects: Anti-infective agents -- Periodicals; Chemotherapy -- Periodicals; 615.58
• DOI: 10.1093/jac/dkab198
• Languages: English
• ISSNs: 0305-7453

Abstract

Abstract: Background: During 2018–19, an increase of vanB vancomycin-resistant Enterococcus faecium (VREfm) was observed in the Capital Region of Denmark. vanA/vanB PCR performed directly on rectal swabs is accurate in detection of vanA ; however, the positive predictive value for vanB -positive samples is low because of the presence of vanB in non-enterococcal gut commensals. Objectives: We investigated the epidemiology and clonal relatedness of vanB VREfm from the period 2015–19 and describe the application of a clone-specific vanB VREfm PCR assay for rapid and accurate detection of vanB VREfm in rectal screening samples. Methods: vanB VREfm were investigated using epidemiological data and WGS data. The SeqSphere+ software was used to analyse MLST and cgMLST, and de novo assemblies were annotated to determine insertion sites for the vanB transposon (Tn 1549 ). A clone-specific vanB VREfm PCR assay was designed to detect the sequence bridging Tn 1549 and the E. faecium chromosome ( araA2 ) in the dominant cluster. Results: Two hundred and seventy-five vanB VREfm isolates were identified, of which 76% were identified in 2019. A dominant cluster (Cluster 1, n = 204, 74%), six minor clusters and 15 singletons were identified. All Cluster 1 isolates and six non-Cluster 1 isolates had Tn 1549 integrated into araA2. In 2019, the PCR assay would have detected 92% of all rectal screening samples containing vanB VREfm. Conclusions: vanB VREfm increased due to the introduction and nosocomial transmission of the successful Cluster 1. The clone-specific PCR assay detected vanB VREfm outbreak isolates in rectal screening samples rapidly and accurately.