Emergence of Vancomycin-Resistant Enterococci at a University Hospital in Taiwan: Persistence of Multiple Species and Multiple Clones

Abstract

AbstractObjectives:To describe the epidemiology of vancomycin-resistant enterococci (VRE) in a university hospital in Taipei, Taiwan.Design:Retrospective review over a 27-month period, from March 1996 to May 1998.Setting:A tertiary-care teaching hospital in Taiwan.Participants:Patients with VRE isolated from any body site.Methods:Patients were identified through hospital microbiology and infection control records. Patient charts were reviewed for clinical and epidemiology data, including age, gender, previous hospital admissions, underlying diseases, types of infection, and recent antibiotic use. VRE isolates were characterized by their typical biochemical reactions, cellular fatty acid profiles, and the presence ofvangenes. Antibiotypes using the E-test and randomly amplified polymorphic DNA (RAPD) patterns of these isolates were used to determine the clonality.Results:Twenty-five isolates of VRE recovered from 12 patients were identified. One patient with a perianal abscess had 12 isolates of VRE (4Enterococcus faecalis, 7Enterococcus faecium, and 1Enterococcus casseliflavus) recovered from perianal lesions. Among 3 patients who were hospitalized in the same room, 1 had a community-acquired cellulitis over the left leg caused byE faecalis, and the other 2 patients both had anal colonization with 2 isolates ofE faecalis. The other 8 patients had 1E faecalisisolate each from various clinical specimens. All isolates possessed vanA resistance phenotype andvanAgenes. Different antibiotypes and RAPD patterns of the isolates from different patients excluded the possibility of nosocomial spread at the hospital.Conclusions:Multiple species of VRE (E faecalis, E faecium, andE casseliflavus) and multiple clones ofE faeciumcould colonize or infect hospitalized patients. In addition, clones of VRE can persist long-term in patients' lower gastrointestinal tracts. These results extend our knowledge of the coexistence and the persistence of multiple species and multiple clones of VRE in hospitalized patients.