The Open Infectious Diseases Journal

2009, 3 : 55-60
Published online 2009 June 23. DOI: 10.2174/1874279300903010055
Publisher ID: TOIDJ-3-55

RESEARCH ARTICLE
 A Large Hospital Outbreak of Klebsiella pneumoniae (DHA-1 and SHV-11 Positive): Importance of Detection and Treatment of ampC β-Lactamases

Timothy Vanwynsberghe1 , Katia Verhamme2 , Marijke Raymaekers3 , Reinoud Cartuyvels3 , Kristien Van Vaerenbergh1 , An Boel1 and Hans de Beenhouwer, *,1
1 Clinical Microbiology, OLV Hospital, Aalst
2 Infection control and epidemiology OLV Hospital, Aalst
3 Clinical Microbiology, Virga-Jesse Hospital, Hasselt, Belgium

* Address correspondence to this author at the OLV hospital, Moorselbaan 164, 9300 Aalst, Belgium. E-mail: hans.de.beenhouwer@olvz-aalst.be

ABSTRACT

Plasmid-borne ampC β-lactamases are emerging worldwide. There is no gold standard in detecting them so it is presumed their prevalence is underestimated. They may confer resistance to broad-spectrum cephalosporins. In this paper the first outbreak in Europe of a Klebsiella pneumoniae harbouring a plasmid-borne DHA-1 β-lactamase and a SHV-11 β- lactamase is reported. Following CLSI (Clinical Laboratories Standards Institute) guidelines the majority of isolates would have been reported susceptible to third generation cephalosporines in spite of increased MIC values. No failures were observed in patients treated with cefepime or meropenem. Infections were linked to stay on the intensive care unit and/or urological interventions. The outbreak was stopped after a meeting was organised between the department of infection control of the hospital and the complete ICU and urology staff in which the importance of strict hand hygiene to limit transmission was stressed.

Keywords:

β-lactamases, AmpC, DHA-1.