Prevalence and determinants of fecal colonization with vancomycin-resistant Enterococcus in hospitalized patients in The Netherlands.
OBJECTIVE
To determine the prevalence and determinants of fecal carriage of vancomycin-resistant enterococci (VRE) in intensive care unit (ICU), hematology-oncology, and hemodialysis patients in The Netherlands.


METHODS
Descriptive, multicenter study, with yearly 1-week point-prevalence assessments between 1995 and 1998.


METHODS
All patients hospitalized on the testing days in ICUs and hematology-oncology wards in nine hospitals in The Netherlands were included.


METHODS
Rectal swabs obtained from 1,112 patients were screened for enterococci in a selective broth and subcultured on selective media with and without 6 mg/L vancomycin. Resistance genotypes were determined by polymerase chain reaction. Further characterization of VRE strains was done by pulsed-field gel electrophoresis (PFGE). We studied possible determinants of VRE colonization with a logistic regression analysis model. Determinants analyzed included gender, age, and log-transformed length of prior hospital stay.


RESULTS
The results showed that 614 (55%) of 1,112 patients were colonized with vancomycin-sensitive enterococci, and 15 (1.4%) of 1,112 carried VRE. No increase in VRE colonization was observed from 1995 to 1998. Eleven strains were identified as Enterococcus faecium and four as Enterococcus faecalis. All E faecium and one E faecalis carried the vanA gene; the other E faecalis strains harbored the vanB gene. PFGE revealed that three vanB VRE isolated from patients hospitalized in one single ICU were related, suggesting nosocomial transmission. Though higher age seemed associated with VRE colonization, exclusion of patients with the nosocomial strain from the regression analysis decreased this relation to nonsignificant. Duration of hospital stay was not associated with VRE colonization.


CONCLUSIONS
VRE colonization in Dutch hospitals is an infrequent phenomenon. Although nosocomial spread occurs, most observed cases were unrelated, which suggests the possibility of VRE acquisition from outside the hospital. Prolonged hospital stay, age, and gender proved unrelated to VRE colonization.
van den Braak
N
N
Department of Medical Microbiology and Infectious Diseases, Erasmus University Rotterdam, The Netherlands.
Ott
A
A
van Belkum
A
A
Kluytmans
J A
JA
Koeleman
J G
JG
Spanjaard
L
L
Voss
A
A
Weersink
A J
AJ
Vandenbroucke-Grauls
C M
CM
Buiting
A G
AG
Verbrugh
H A
HA
Endtz
H P
HP
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D002675:Child, Preschool; D003428:Cross Infection / Q000635:transmission*; D004269:DNA, Bacterial / Q000032:analysis; D013293:Enterococcus faecalis / Q000187:drug effects* / Q000472:pathogenicity; D016984:Enterococcus faecium / Q000187:drug effects* / Q000472:pathogenicity; D005243:Feces / Q000382:microbiology; D005260:Female; D005838:Genotype; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007362:Intensive Care Units; D008297:Male; D008875:Middle Aged; D009426:Netherlands / Q000453:epidemiology; D016133:Polymerase Chain Reaction; D015995:Prevalence; D020713:Vancomycin Resistance
D004269:DNA, Bacterial