Plasmid DNA and Random Amplified Polymorphic DNA (RAPD) Analyses of Vancomycin-Resistant Enterococcus faecium Isolates / 대한임상병리학회지

ABSTRACT

BACKGROUND: Vancomycin-resistant enterococci (VRE) have been increasingly reported worldwide. The understanding of VRE dissemination in the hospital requires a molecular typing of the strains. VRE appeared recently in Chonnam University Hospital. The purpose of this study is to analyse the strains for their genetic relatedness. METHODS: Nine vancomycin-resistant E. faecium isolates, collected from six patients during 1995-1996 in Chonnam University Hospital, were typed using plasmid DNA and RAPD analyses. The plasmid DNA of the isolates was obtained by a alkaline lysis method. For RAPD, eight random primers were used. The cluster analysis was performed by NTSYS-pc (numerical taxonomy system and multivariate analysis system, version 1.50, Applied Biostatistics Inc., CA). RESULTS: Nine VRE isolates were separated into two different molecular types (group A and B) by the plasmid DNA patterns, which were agreed with the RAPD results: the isolates of each group showed the same plasmid DNA patterns and high similarity values in the RAPD analysis. Group A was consisted of two strains isolated from two patients who were admitted at the same room in May 1995. Seven strains of group B were isolated from four patients in the different wards during June 1995 to June 1996. CONCLUSIONS: Nine VRE isolates from six patients were typed to two groups by plasmid DNA or RAPD analysis. These results suggested the intrahospital spread of two clonal strains of vancomycin-resistant E. faecium.