Outbreak of hospital-adapted clonal complex-17 vancomycin-resistant Enterococcus faecium strain in a haematology unit: role of rapid typing for early control.
OBJECTIVE
To describe the investigation and molecular characterization of a vancomycin-resistant Enterococcus faecium (VREF) strain responsible for a nosocomial outbreak in the haematology unit of a tertiary-care university hospital.


METHODS
Two patients admitted to the haematology unit developed infection/colonization with VREF over a 3 month period when compared with none in the 2 previous years. On the basis of the identification of a clonal link between these two strains, weekly rectal screening was implemented for all patients in the haematology unit and contact precautions were extended to VREF carriers. In the following 6 month period, 11 patients colonized with VREF were detected. No further case was detected in the following 1 year period.


RESULTS
VREF isolates from the haematology unit carried the vanA gene and were multiresistant to antimicrobial agents, including high-level resistance to vancomycin, teicoplanin and ampicillin. This resistance profile restricted the choice of antimicrobial therapy to linezolid or investigational drugs such as tigecycline. Molecular analysis showed that 11 of 13 (85%) VREF isolates belonged to pandemic clonal complex-17 carrying the esp and hyl virulence genes.


CONCLUSIONS
Rapid typing and infection control measures, including early reinforcement of barrier precautions combined with weekly rectal surveillance cultures, were followed by control of nosocomial spread of this VREF clone.
Deplano
A
A
Department of Microbiology, Erasme Hospital, Université Libre de Bruxelles, Brussels, Belgium. ariane.deplano@ulb.ac.be
Denis
O
O
Nonhoff
C
C
Rost
F
F
Byl
B
B
Jacobs
F
F
Vankerckhoven
V
V
Goossens
H
H
Struelens
M J
MJ
D000900:Anti-Bacterial Agents / Q000494:pharmacology* / Q000627:therapeutic use; D001426:Bacterial Proteins / Q000235:genetics; D015373:Bacterial Typing Techniques; D001530:Belgium / Q000453:epidemiology; D019729:Carbon-Oxygen Ligases / Q000235:genetics; D003428:Cross Infection / Q000188:drug therapy / Q000453:epidemiology / Q000382:microbiology*; D016172:DNA Fingerprinting; D004196:Disease Outbreaks; D024901:Drug Resistance, Multiple, Bacterial; D016521:Electrophoresis, Gel, Pulsed-Field; D016984:Enterococcus faecium / Q000145:classification* / Q000187:drug effects / Q000302:isolation & purification; D005243:Feces / Q000382:microbiology; D005838:Genotype; D016908:Gram-Positive Bacterial Infections / Q000188:drug therapy / Q000453:epidemiology / Q000382:microbiology*; D006785:Hospitals, University; D006801:Humans; D008826:Microbial Sensitivity Tests; D010641:Phenotype; D020713:Vancomycin Resistance; D037521:Virulence Factors / Q000235:genetics
D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; C071437:VanA ligase, Bacteria; D037521:Virulence Factors; D019729:Carbon-Oxygen Ligases