Surveillance of Vancomycin-resistant Enterococci colonization with GeneXpert vanA/vanB test and culture method

Objectives: Early detection of vancomycin resistant enterococci (VRE) colonization in hospitalized patients plays an important role in controlling enterococcal infections. For this purpose, the detection of VRE from rectal swab specimens can be performed with various methods. Methods: In this study, VRE colonization in the rectal swab samples of patients from intensive care units, burn unit, and infectious diseases clinic in our hospital were evaluated. In total, 2,394 rectal swab samples from 1,627 patients were collected between January 2012 and 2013. A commercial product (Enterococcosel agar) was used for cultivating, and the growing bacteria were identified with conventional methods and/or the VITEK 2 Compact system (BioMerieux, France). The samples of the patients transferred from another hospital and who had a history of VRE infection or carriage were examined with an automated real-time PCR system (Gene XpertTM vanA/vanB, Cepheid, Sunnyvale, CA). Results: A total of 59 (3.6%) patients were positive for VRE, 25 were diagnosed with PCR, and 34 were diagnosed with culture methods. Among the samples identified by PCR, 19 were only vanA harboring VRE, five were only vanB harboring VRE, and one was both vanA and vanB harboring VRE. All of the VRE isolates were identified as E. faecium. The number of patients administered with vancomycin therapy before being diagnosed with VRE was 11(18.6%). Conclusions: It is important to determine the appropriate surveillance method for the early diagnosis of VRE carriers among patients at risk according to their patient profile, needs, and resources. J Microbiol Infect Dis 2014; 4(3): 97-101