Carbapenem-resistant Klebsiella pneumoniae infections in a Greek intensive care unit: Molecular characterisation and treatment challenges

Acquisition of carbapenemase-producing Klebsiella pneumoniae (CP-Kp) strains poses a major threat to critically ill patients. The objectives of this study were to describe the epidemiology of CP-Kp isolates as well as the clinical outcome associated with the corresponding infections and to identify risk factors for mortality of intensive care unit (ICU) patients in a Greek hospital. A prospective, observational study was conducted in a nine-bed general ICU over a 2-year period (April 2010-March 2012). Imipenem-resistant K. pneumoniae isolates recovered from clinical samples of ICU patients were prospectively collected and studied for the presence of carbapenemases. Isolates were submitted to molecular typing using pulsed-field gel electrophoresis (PFGE). In total, 61 CP-Kp isolates (48 KPC-producers and 13 VIM-producers) were recovered from 58 ICU patients. The majority of KPC-producers were classified into a single PFGE type, indicating potent clonal dissemination. Among the 32 infected patients, bacteraemia was diagnosed in 16. Tigecycline + colistin was the most common combination antimicrobial regimen. Infection-attributable mortality was 43.8%. Regarding mortality risk factors, non-survivors were older (P = 0.080), all of them presented with septic shock (P = 0.010) and they had higher Sepsis-related rim Failure Assessment (SOFA) scores at infection onset (P = 0.004) compared with survivors. Appropriate definitive treatment and combination regimens were not associated with patient survival. In conclusion, CP-Kp infections are associated with limited treatment options and high in-hospital mortality. Effective measures for preventing dissemination of respective isolates in the hospital setting are required. (C) 2015 International Society for Chemotherapy of Infection and Cancer. Published by Elsevier Ltd. All rights reserved.