Susceptibility of Klebsiella pneumoniae Isolates from Intra-Abdominal Infections, and Molecular Characterization of Ertapenem-Resistant Isolates
ABSTRACT 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 - 2009. Overall, 22.4% of isolates had extended-spectrum beta-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 compared with ESBL-negative isolates. Globally, 6.5% of isolates were ertapenem-resistant based upon the June 2010 clinical breakpoints published by the Clinical and Laboratory Standards Institute, with MICs >/=1mug/ml. Molecular characterization of 43 isolates with ertapenem MICs >/= 4 mug/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 is needed.
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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). · 0.92 Impact Factor
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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; 11:103. · 2.11 Impact Factor
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ABSTRACT: Few reports about the prevalence and genetic basis of extended spectrum beta-lactamases (ESBLs) are available from Saudi Arabia. We sought to determine the prevalence of ESBL-producing Enterobacteriaceae in a university hospital in eastern Saudi Arabia and to characterize the ESBLs produced by these isolates at the molecular level. All clinical isolates of Escherichia coli, Klebsiella spp., and Proteus spp. collected over two years were evaluated for susceptibility to a panel of antimicrobials and were analyzed for the ESBL phenotype using screening and confirmatory tests. ESBL-positive isolates were then screened for the presence of genes encoding CTX-M, SHV, and TEM beta-lactamases by PCR. The overall prevalence of ESBL-producing isolates was 4.8% (253/5256). Most isolates (80%) were from the inpatient department. The ESBL phenotype was more frequently detected in K. pneumonia. CTX-M genes were the most prevalent ESBL genes, detected in 82% of the studied isolates. The ESBL producers demonstrated a high multidrug resistance rate (96.6%). In transconjugation assay, the same ESBL gene pattern was transmitted from 29.7% of K. pneumoniae donors to the recipient strain, and the latter exhibited concomitant decreased aminoglycosides and co-trimoxazole susceptibility. We observed the presence of ESBL screen-positive but confirmatory-negative isolates (8.9%). Phenotypic tests for the production of AmpC β-lactamase tested positive in 52% of these isolates. Further studies are needed for appropriate detection of concomitant ESBL and AmpC enzyme production among such isolates. Continued surveillance and judicious antibiotic usage together with the implementation of efficient infection control measures are absolutely required.The Journal of Infection in Developing Countries 01/2013; 7(8):618-29. · 1.00 Impact Factor