Abstract
A laboratory-developed test (Lab Assay), combining enrichment broth and real-time polymerase chain reaction (PCR) for vancomycin-resistant enterococci (VRE) screening, was developed and evaluated in this study. A total of 1,765 faecal or rectal swabs sent to the laboratory for VRE screening were investigated in parallel by Lab Assay and the Roche LightCycler VRE detection kit-based method. The diagnostic values for Lab Assay were as follows: 100% sensitivity, 79.92% specificity, 1.94% positive predictive value and 100% negative predictive value, which were comparable to the results from the LightCycler kit-based assay. The detection limit of Lab Assay was 100 to 101 colony-forming units (CFU)/ml of inoculum in broth for both VanA-type and VanB-type VRE. The PCR method developed in this study was approved to be applicable on both the Applied Biosystems 7500 Fast Real-Time PCR System and the LightCycler® 480 Real-Time PCR System. The flexibility in choosing PCR systems makes it possible that the PCR assay could be fully compatible with the DNA extraction’s platform, providing an integrated workflow. Furthermore, the material cost is saved at 7EUR per sample when Lab Assay replaces the commercial kit-based method in our routine screening for VRE. Therefore, the laboratory-developed broth–PCR method is an efficient and economical assay for VRE screening.
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References
Deshpande LM, Fritsche TR, Moet GJ, Biedenbach DJ, Jones RN (2007) Antimicrobial resistance and molecular epidemiology of vancomycin-resistant enterococci from North America and Europe: a report from the SENTRY antimicrobial surveillance program. Diagn Microbiol Infect Dis 58(2):163–170
Fang H, Nord CE, Ullberg M (2010) Screening for vancomycin-resistant enterococci: results of a survey in Stockholm. APMIS 118(5):413–417
Hidron AI, Edwards JR, Patel J, Horan TC, Sievert DM, Pollock DA, Fridkin SK (2008) NHSN annual update: antimicrobial-resistant pathogens associated with healthcare-associated infections: annual summary of data reported to the National Healthcare Safety Network at the Centers for Disease Control and Prevention, 2006–2007. Infect Control Hosp Epidemiol 29(11):996–1011
Zhu X, Zheng B, Wang S, Willems RJ, Xue F, Cao X, Li Y, Bo S, Liu J (2009) Molecular characterisation of outbreak-related strains of vancomycin-resistant Enterococcus faecium from an intensive care unit in Beijing, China. J Hosp Infect 72(2):147–154
Willems RJ, Top J, van Santen M, Robinson DA, Coque TM, Baquero F, Grundmann H, Bonten MJ (2005) Global spread of vancomycin-resistant Enterococcus faecium from distinct nosocomial genetic complex. Emerg Infect Dis 11(6):821–828
Hsieh YC, Lee WS, Ou TY, Hsueh PR (2010) Clonal spread of CC17 vancomycin-resistant Enterococcus faecium with multilocus sequence type 78 (ST78) and a novel ST444 in Taiwan. Eur J Clin Microbiol Infect Dis 29(1):25–30
Ostrowsky BE, Trick WE, Sohn AH, Quirk SB, Holt S, Carson LA, Hill BC, Arduino MJ, Kuehnert MJ, Jarvis WR (2001) Control of vancomycin-resistant enterococcus in health care facilities in a region. N Engl J Med 344(19):1427–1433
Palladino S, Kay ID, Flexman JP, Boehm I, Costa AM, Lambert EJ, Christiansen KJ (2003) Rapid detection of vanA and vanB genes directly from clinical specimens and enrichment broths by real-time multiplex PCR assay. J Clin Microbiol 41(6):2483–2486
Arthur M, Molinas C, Depardieu F, Courvalin P (1993) Characterization of Tn1546, a Tn3-related transposon conferring glycopeptide resistance by synthesis of depsipeptide peptidoglycan precursors in Enterococcus faecium BM4147. J Bacteriol 175(1):117–127
Evers S, Courvalin P (1996) Regulation of VanB-type vancomycin resistance gene expression by the VanS(B)–VanR (B) two-component regulatory system in Enterococcus faecalis V583. J Bacteriol 178(5):1302–1309
Lorenzo-Díaz F, Delgado T, Reyes-Darias JA, Flores C, Méndez-Alvarez S, Villar J, Sierra A, Claverie-Martín F (2004) Characterization of the first VanB vancomycin-resistant Enterococcus faecium isolated in a Spanish hospital. Curr Microbiol 48(3):199–203
Kawalec M, Gniadkowski M, Kedzierska J, Skotnicki A, Fiett J, Hryniewicz W (2001) Selection of a teicoplanin-resistant Enterococcus faecium mutant during an outbreak caused by vancomycin-resistant enterococci with the vanB phenotype. J Clin Microbiol 39(12):4274–4282
Lu JJ, Perng CL, Ho MF, Chiueh TS, Lee WH (2001) High prevalence of VanB2 vancomycin-resistant Enterococcus faecium in Taiwan. J Clin Microbiol 39(6):2140–2145
Dutka-Malen S, Evers S, Courvalin P (1995) Detection of glycopeptide resistance genotypes and identification to the species level of clinically relevant enterococci by PCR. J Clin Microbiol 33(1):24–27
Ballard SA, Grabsch EA, Johnson PD, Grayson ML (2005) Comparison of three PCR primer sets for identification of vanB gene carriage in feces and correlation with carriage of vancomycin-resistant enterococci: interference by vanB-containing anaerobic bacilli. Antimicrob Agents Chemother 49(1):77–81
Hawkins RC (2007) Laboratory turnaround time. Clin Biochem Rev 28(4):179–194
Woodford N, Johnson AP, Morrison D, Chin AT, Stephenson JR, George RC (1990) Two distinct forms of vancomycin resistance amongst enterococci in the UK. Lancet 335(8683):226
Pendle S, Jelfs P, Olma T, Su Y, Gilroy N, Gilbert GL (2008) Difficulties in detection and identification of Enterococcus faecium with low-level inducible resistance to vancomycin, during a hospital outbreak. Clin Microbiol Infect 14(9):853–857
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Fang, H., Ohlsson, AK., Jiang, GX. et al. Screening for vancomycin-resistant enterococci: an efficient and economical laboratory-developed test. Eur J Clin Microbiol Infect Dis 31, 261–265 (2012). https://doi.org/10.1007/s10096-011-1304-0
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DOI: https://doi.org/10.1007/s10096-011-1304-0