An outbreak of infection due to beta-Lactamase Klebsiella pneumoniae Carbapenemase 2-producing K. pneumoniae in a Greek University Hospital: molecular characterization, epidemiology, and outcomes

Clin Infect Dis. 2010 Feb 1;50(3):364-73. doi: 10.1086/649865.


Background: We describe the emergence and spread of Klebsiella pneumoniae carbapenemase 2 (KPC-2)-producing K. pneumoniae at a Greek University hospital.

Methods: Isolates with a carbapenem minimum inhibitory concentration >1 microg/mL and a negative EDTA-imipenem disk synergy test result were submitted to boronic acid disk test and to polymerase chain reaction (PCR) for KPC gene and sequencing. Records from patients who had KPC-2-producing K. pneumoniae isolated were retrospectively reviewed. Clinical isolates were submitted to molecular typing using pulsed-field gel electrophoresis, and the beta-lactamase content was studied using isoelectric focusing and PCR.

Results: From January 2007 through December 2008, 50 patients (34 in the intensive care unit [ICU]) were colonized (n = 32) or infected (n = 18) by KPC-2-producing K. pneumoniae. Increasing prevalence of KPC-2-producing K. pneumoniae coincided with decreasing prevalence of metallo-beta lactamase-producing isolates in our ICU. Multidrug resistance characterized the studied isolates, with colistin, gentamicin, and fosfomycin being the most active agents. Besides KPC-2, clinical isolates encoded TEM-1-like, SHV-11, SHV-12, CTX-M-15, and LEN-19 enzymes. Four different clonal types were detected; the predominant one comprised 41 single patient isolates (82%). Sporadic multiclonal cases of KPC-2-producing K. pneumoniae infection were identified from September 2007 through May 2008. The outbreak strain was introduced in February 2008 and disseminated rapidly by cross-transmission; 38 patients (76%) were identified after August 2008. Fourteen cases of bacteremia, 2 surgical site infections, 2 lower respiratory tract infections (1 bacteremic), and 1 urinary tract infection were identified. Most patients received a colistin-containing combination treatment. Crude mortality was 58.8% among ICU patients and 37.5% among non-ICU patients, but attributable mortality was 22.2% and 33.3%, respectively.

Conclusions: The emergence of KPC-2-producing K. pneumoniae in Greek hospitals creates an important challenge for clinicians and hospital epidemiologists, because it is added to the already high burden of antimicrobial resistance.

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Anti-Bacterial Agents / therapeutic use*
  • Bacterial Proteins / biosynthesis*
  • Bacterial Typing Techniques*
  • DNA Fingerprinting
  • Disease Outbreaks*
  • Electrophoresis, Gel, Pulsed-Field
  • Female
  • Greece / epidemiology
  • Hospitals, University
  • Humans
  • Intensive Care Units
  • Klebsiella Infections / drug therapy
  • Klebsiella Infections / epidemiology*
  • Klebsiella Infections / microbiology
  • Klebsiella pneumoniae / classification
  • Klebsiella pneumoniae / enzymology*
  • Klebsiella pneumoniae / isolation & purification
  • Male
  • Microbial Sensitivity Tests
  • Middle Aged
  • Molecular Epidemiology
  • Treatment Outcome
  • beta-Lactam Resistance*
  • beta-Lactamases / biosynthesis*


  • Anti-Bacterial Agents
  • Bacterial Proteins
  • beta-Lactamases
  • carbapenemase-2, Klebsiella pneumoniae