The Epidemiological Study of Vancomycin Resistant Enterococci by Pulsed Field Gel Electrophoresis

Abstract

Vancomycin resistant enterococci (VRE) has been isolated in many hospitals in Korea and other countries. For the epidemiological investigation of the VRE, pulsed-field gel electrophoresis (PFGE) was employed in this study. Among the available techniques, pulsed-field gel electrophoresis (PFGE) has gained wide acceptance as an excellent method for the typing of bacteria at the subspecies level in terms of discriminatory power and reproducibility. Twenty-five isolates of Enterococcus faecium with the VanA gene were used As the controls, five isolates from Kuro hospital were also applied to this PFGE. We used the rapid method by Turabelidze, D et al. Isolateswere grouped into 5 major phylogenetic divisions (A,B,C,D and E) and subsequently to 11 PFGE groups. The five isolates that were referred as the controls belonged to division C, while 3, 8, 4 and 10 isolates to divisions A, B, D and E, respectively. According to the results, it isdifficult to confirm exactly if VRE infection in hospital E comes from the hospital infection or the outbreak. However, 5 isolates from hospital K tested for the control are considerably differentiated from the other 25 isolates from hospital E and highly correlated with one another. Also, it can be said that this correlation indicates the possibility of hospital infection.