Molecular Typing of Enterococci/Vre

Abstract

With their increased frequency of occurrence as a nosocomial pathogen and thus their elevated overall medical importance, the demand to characterize and differentiate strains of Enterococcus faecalis and E. faecium has risen. Available techniques vary in ease of use, demands in costs, manpower and time, inter- and intra-laboratory comparability and reproducibility of results, portability of data and discriminatory power. Analysing outbreaks by sophisticated molecular techniques requires methods with a different discrimination than methods to detect and follow transmission of epidemic strains over longer time periods. The latter is especially critical for bacteria showing a rather flexible genome such as Enterococcus. The value and application for commonly used techniques for typing (vancomycinresistant) enterococci is discussed including ribotyping, PCR-based typing, macrorestriction analysis in Pulsed-Field Gel Electrophoresis (PFGE), Amplified Fragment Length Polymorphism (AFLP), Multiple Locus Variable Number of Tandem Repeat Analyses (MLVA), Multi-Locus Sequence Typing (MLST) and some specialist approaches (resistance cluster typing, plasmid typing, next generation sequencing).