Susceptibility of Klebsiella pneumoniae Isolates from Intra-Abdominal Infections, and Molecular Characterization of Ertapenem-Resistant Isolates

IHMA Europe Sàrl, 1066 Epalinges, Switzerland.
Antimicrobial Agents and Chemotherapy (Impact Factor: 4.48). 07/2011; 55(8). DOI: 10.1128/AAC.00070-11


A total of 2,841 clinical isolates of Klebsiella pneumoniae from intra-abdominal infections worldwide were collected in the Study for Monitoring Antimicrobial Resistance Trends (SMART)
during 2008 and 2009. Overall, 22.4% of isolates had extended-spectrum β-lactamases (ESBLs). The most active antibiotics among
the 11 tested were imipenem, amikacin, and ertapenem, though even these, like all other comparators, were less consistently
active against ESBL-positive isolates than against ESBL-negative isolates. Globally, 6.5% of isolates were ertapenem resistant
based on the June 2010 clinical breakpoints published by the Clinical and Laboratory Standards Institute, with MICs of ≥1
μg/ml. Molecular characterization of 43 isolates with ertapenem MICs of ≥4 μg/ml showed that they variously produced CTX-M
or SHV ESBLs combined with altered impermeability and/or had KPC (n = 28), OXA-48 (n = 3), or VIM (n = 1) carbapenemases. Further monitoring of ertapenem susceptibility and molecular characterization of ertapenem-resistant
isolates are needed.

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Available from: Neil Woodford, Jun 21, 2014
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    • "The recent and rapid spread of serine carbapenemases in Klebsiella pneumoniae (KPC) has become an important concern when administering antimicrobial therapy in hospitals worldwide [14]. "
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    ABSTRACT: Despite advances in diagnosis, surgery, and antimicrobial therapy, mortality rates associated with complicated intra-abdominal infections remain exceedingly high. The World Society of Emergency Surgery (WSES) has designed the CIAOW study in order to describe the clinical, microbiological, and management-related profiles of both community- and healthcare-acquired complicated intra-abdominal infections in a worldwide context. The CIAOW study (Complicated Intra-Abdominal infection Observational Worldwide Study) is a multicenter observational study currently underway in 57 medical institutions worldwide. The study includes patients undergoing surgery or interventional drainage to address complicated intra-abdominal infections. This preliminary report includes all data from almost the first two months of the six-month study period. Patients who met inclusion criteria with either community-acquired or healthcare-associated complicated intra-abdominal infections (IAIs) were included in the study. 702 patients with a mean age of 49.2 years (range 18–98) were enrolled in the study. 272 patients (38.7%) were women and 430 (62.3%) were men. Among these patients, 615 (87.6%) were affected by community-acquired IAIs while the remaining 87 (12.4%) suffered from healthcare-associated infections. Generalized peritonitis was observed in 304 patients (43.3%), whereas localized peritonitis or abscesses was registered in 398 (57.7%) patients. The overall mortality rate was 10.1% (71/702). The final results of the CIAOW Study will be published following the conclusion of the study period in March 2013.
    World Journal of Emergency Surgery 01/2013; 8(1). DOI:10.1186/1749-7922-8-1 · 1.47 Impact Factor
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    • "Different surgical approaches have recently been suggested in patients with monomicrobial K. pneumoniae liver abscess (e.g. ultrasonography-guided percutaneous liver aspiration with retained catheter), whereas antimicrobial therapy strictly depends upon monitoring in vitro antimicrobial susceptibility using the clinical breakpoints defined by the European Committee on Antimicrobial Susceptibility Testing (EUCAST) [23,24]. "
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    ABSTRACT: Knowledge of the etiology of pyogenic liver and pancreatic abscesses is an important factor in determining the success of combined surgical and antibiotic treatment. Literature shows geographical variations in the prevalence and distribution of causative organisms, and the spread of Klebsiella pneumoniae carbapenemase-producing bacteria is an emerging cause of abdominal infections. We herein describe two cases of intra-abdominal abscesses due to monomicrobial infection by Klebsiella pneumoniae Sequence Type 258 producing K. pneumoniae carbapenemase 3 (KPC-Kp). In case 1, a 50-year-old HIV-negative Italian woman with chronic pancreatitis showed infection of a pancreatic pseudocystic lesion caused by KPC-Kp. In case 2, a 64-year-old HIV-negative Italian woman with pancreatic neoplasm and liver metastases developed a liver abscess due to KPC after surgery. Both women were admitted to our hospital but to different surgical units. The clonal relationship between the two isolates was investigated by pulsed-field gel electrophoresis (PFGE). In case 2, the patient was already colonized at admission and inter-hospital transmission of the pathogen was presumed. A long-term combination regimen of colistin with tigecycline and percutaneous drainage resulted in full recovery and clearance of the multidrug-resistant (MDR) pathogen. Timely microbiological diagnosis, the combined use of new and old antibiotics and radiological intervention appeared to be valuable in managing these serious conditions. The emergence and dissemination of MDR organisms is posing an increasing challenge for physicians to develop new therapeutic strategies and control and prevention frameworks.
    BMC Gastroenterology 09/2011; 11(1):103. DOI:10.1186/1471-230X-11-103 · 2.37 Impact Factor
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    ABSTRACT: To investigate the in vitro susceptibility of ertapenem-non-susceptible Enterobacteriaceae (ENSE) isolates to cefotaxime, ceftazidime, cefepime and aztreonam. Clinical isolates of ENSE tested in this study were obtained from 10 major teaching hospitals in Taiwan during the period January 2008 to October 2010. MICs of ertapenem, cefotaxime, ceftazidime, cefepime and aztreonam were determined by the agar dilution method and were interpreted based on 2011 MIC interpretive criteria recommended by the CLSI and EUCAST. A total of 412 non-duplicate ENSE isolates (with ertapenem MIC values ≥ 0.5 mg/L) were tested. These comprised 72 isolates of Escherichia coli [28 (38.9%) were extended-spectrum β-lactamase (ESBL)-producing isolates], 167 isolates of Klebsiella pneumoniae [74 (44.3%) were ESBL-producing isolates], 115 isolates of Enterobacter cloacae, 13 isolates of Enterobacter aerogenes, 20 isolates of Citrobacter freundii and 25 isolates of Serratia marcescens. According to 2011 CLSI (EUCAST) MIC interpretive breakpoints for Enterobacteriaceae, 64% (31%) of all ENSE isolates, 45.8% (16.7%) of E. coli isolates, 53% (29.3%) of K. pneumoniae isolates and 86.1% (35.7%) of E. cloacae isolates were susceptible to cefepime. As for ESBL-producing ENSE isolates, 25% and 14.3% of E. coli isolates and 36.5% and 10.8% of K. pneumoniae isolates were susceptible to cefepime based on CLSI and EUCAST criteria, respectively. Cefepime exerts in vitro antimicrobial activity against a significant portion of clinical isolates of ENSE, although there are discrepancies between results obtained using the CLSI-2011 and EUCAST-2011 guidelines.
    Journal of Antimicrobial Chemotherapy 02/2012; 67(6):1413-21. DOI:10.1093/jac/dks042 · 5.31 Impact Factor
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