An investigation of vancomycin-resistant Enterococcus faecium within the pediatric service of a large urban medical center.
BACKGROUND
Between 1990 to 1992 and 1993 to 1995 there was a >5-fold increase (16.7% to 89.8%) in vancomycin-resistant Enterococcus faecium isolates as a percentage of all isolates of vancomycin-resistant enterococci on the pediatric units of The New York Hospital-Cornell Medical Center (NYH-CMC). A molecular epidemiologic investigation was undertaken to determine the extent to which this increase was associated with the spread of a vanA-containing clone of vancomycin-resistant E. faecium that had been previously defined in adults hospitalized at NYH-CMC or with the spread of another vanA clone that had been defined in children hospitalized on the pediatric service at Memorial Sloan-Kettering Cancer Center, which shares a common pediatric intensive care unit and pediatric house staff with NYH-CMC.


METHODS
Molecular genotyping of vancomycin-resistant E. faecium isolates obtained from pediatric patients from 1993 to 1995 was performed by pulsed field gel electrophoresis of chromosomal SmaI digests. Southern hybridization was performed using vanA- and vanB-specific probes. Medical records of patients were reviewed for pertinent clinical and demographic information.


RESULTS
A single vanB clone of vancomycin-resistant E. faecium was responsible for 17 (77.3%) of 22 isolates in the neonatal intensive care unit (NICU) of NYH-CMC. Two other vanB strains of vancomycin-resistant E. faecium and 2 vanA strains were identified among the 5 remaining NICU isolates. Vancomycin-resistant E. faecium isolates from the other pediatric units represented a heterogeneous population of primarily vanA strains, but vanA clonal strains previously identified from patients on adult services at NYH-CMC and from children hospitalized at Memorial Sloan-Kettering Cancer Center were not detected.


CONCLUSIONS
A newly identified vanB clone was responsible for the increase in vancomycin-resistant E. faecium isolates in the NICU of NYH-CMC. The increase of vancomycin-resistant E. faecium among children hospitalized at NYH-CMC was unrelated to the spread of vancomycin-resistant E. faecium among adults in the same hospital or among children at an affiliated facility cared for by the same house staff and sharing a common pediatric intensive care unit.
McNeeley
D F
DF
Division of Pediatric Infectious Diseases, The New York Hospital-Cornell Medical Center, NY 10021, USA. gjnoel@mail.med.cornell.edu
Brown
A E
AE
Noel
G J
GJ
Chung
M
M
De Lencastre
H
H
D000293:Adolescent; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002648:Child; D002675:Child, Preschool; D003428:Cross Infection / Q000188:drug therapy* / Q000453:epidemiology; D004269:DNA, Bacterial / Q000032:analysis; D004352:Drug Resistance, Microbial; D016521:Electrophoresis, Gel, Pulsed-Field; D016984:Enterococcus faecium / Q000187:drug effects* / Q000235:genetics; D016908:Gram-Positive Bacterial Infections / Q000188:drug therapy* / Q000453:epidemiology; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007363:Intensive Care Units, Neonatal; D015278:Intensive Care Units, Pediatric; D014640:Vancomycin / Q000494:pharmacology*
D000900:Anti-Bacterial Agents; D004269:DNA, Bacterial; D014640:Vancomycin