Evaluation of metallo-b-lactamase producing Klebsiella pneumoniae epidemiology in a Greek hospital (2004–2006)

Abstract number: 1733_857

Moraitou H., Kentrou N., Galani I., Tsagarakis N., Makarona M., Gioga A., Kanavaki S.

Objectives: Nosocomial infections due to the dissemination of multi-resistant metallo-b-lactamase producing K. pneumoniae within the hospital setting are of growing concern worldwide. The aim of this study was to retrospectively analyse all MBL-positive K. pneumoniae strains isolated in our laboratory, from 2004 (first isolation) to 2006.

Methods: A total of 52 carbapenem resistant K. pneumoniae strains were isolated and collected since March 2004 to September 2006. 39/52 (75.0%) derived from ICU patients and the rest 13/52 (25.0%) from patients in different wards of our Hospital. 18/52 (34.6%) strains were isolated in 2004, 23/52 (44.2%) in 2005 and 11/52 (21.2%) in 2006. All isolates were tested for imipenem resistance by E-test, and for MBL production by imipenem/EDTA disk synergy test and PCR. Molecular typing was performed by REP-PCR.

Results: All isolates showed reduced susceptibility (MIC > 0.25) or resistance to imipenem (MIC > 8) as well as resistance to all cephalosporins. In addition, all strains were positive for MBL production by EDTA synergy test and PCR experiments detected blaVIM gene. Molecular typing by REP-PCR revealed 14 K. pneumoniae clones (A-N), with predominant the clone A (17/52, 32.7%) throughout the period studied. It is interesting that clusters of the same or related clones were noted in ICU, being responsible for infections appeared in March 2004 (7 strains, clone A), March 2005 (6 strains, clone B), and May 2005 (6 strains, clone J). In addition, the Oncology Unit revealed one small cluster of infections in July 2006 (2 strains, clone F).

Conclusions: All carbapenem-resistant K. pneumoniae isolated in our laboratory were blaVIM positive. We observed three clusters of clonal K. pneumoniae infections as well as six single unrelated clones throughout the study period. The emergence of MBL-producing K. pneumoniae is of great concern and measures should be taken in order to avoid dissemination of highly resistant strains within hospital setting.

Session Details

Date: 31/03/2007
Time: 00:00-00:00
Session name: European Society of Clinical Microbiology and Infectious Diseases
Location: ICC, Munich, Germany
Presentation type:
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