A Simple and Rapid Low-Cost Procedure for Detection of Vancomycin-Resistance Genes in Enterococci Reveals an Outbreak of Vancomycin-Variable <i>Enterococcus faecium</i>

oleh: Hozan Muhammed Abdullah, Lis Høy Marbjerg, Lise Andersen, Silje Vermedal Hoegh, Michael Kemp

Format: Article
Diterbitkan: MDPI AG 2022-08-01

Deskripsi

The detection of resistance to vancomycin in enterococci cultured from patients is important for the treatment of individual patients and for the prevention of hospital transmission. Phenotypic antimicrobial resistance tests may fail to detect potential vancomycin-resistant enterococci. We have developed and tested a PCR based procedure for routine screening for vancomycin-resistance genes in clinical samples with enterococci. Primary cultures from diagnostic samples reported with growth of <i>Enterococcus faecium</i> or <i>E. facalis</i> were tested for <i>vanA</i> and <i>vanB</i> genes by real-time PCR without the isolation of specific bacteria. Up to ten samples were pooled and tested in each real-time PCR reaction, with subsequent individual testing of cultures from positive pools. In a one-month test period in 2017 <i>vanA</i> gene was detected in one out of 340 urine samples with vancomycin-susceptible enterococci reported from diagnostic culture. A second test period in 2018 included 357 urine samples, and <i>vanA</i> gene was detected in samples from eight patients. Subsequently, all urine samples reported with growth of <i>E. faecium</i> during a period of one year were tested. Fifty-eight individuals were identified with enterococci, carrying the <i>vanA</i> gene not previously detected. Routine molecular testing of primary culture material from patient samples may improve the detection of hospitalized patients carrying <i>E. faecium</i> with resistance genes to vancomycin.