Comparison of Multilocus Variable-Number Tandem-Repeat Analysis with Multilocus Sequence Typing and Pulsed-Field Gel Electrophoresis for Enterococcus faecalis

Abstract

A b s t r a c tEnterococcus faecalis represents recently an important etiological agent of health care-associated infections (HAIs) and there is a need for evaluation and comparison of typing methods available for this microorganism. We tested multilocus VNTR (variable-number tandem repeats) analysis (MLVA) on a well-characterized collection of 153 clinical isolates of E. faecalis, corresponding to 52 multilocus sequence types and 67 pulsed-field gel electrophoresis (PFGE) profiles. MLVA showed high discriminatory power, discerning 111 di erent types (diversity index equal 98.9%). e concordance MLVA/MLST and MLVA/PFGE was 0.95 and 0.74, respectively. High discriminatory power of MLVA indicates its utility for local epidemiology such as outbreak investigation, and for di erentiation of clones defined by other methods. K e y w o r d s: E. faecalis clones, MLST, PFGE, VNTR

Molecular Typing of Enterococci/Vre

“…In the initial study this scheme was comparably discriminatory as PFGE typing for the set of investigated E. faecalis strains (VRE and VSE). The E. faecalis MLVA scheme has only scarcely been used since its introduction and thus its general usefulness for typing E. faecalis strains cannot be properly assessed [36,37].…”

“…mlst.net/; managed by: Rob Willems and Janetta Top (UMC Utrecht, NL, hosted by the Imperial College London and funded by the Wellcome Trust, UK). Consequently, most of the recent papers using MLST for E. faecalis rely on the scheme of Ruiz-Garbajosa et al [37,45,49,51,52]. Population structure of E. faecalis appears somehow different from that of E. faecium.…”