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.
Article: Two cases of monomicrobial intraabdominal abscesses due to KPC--3 Klebsiella pneumoniae ST258 clone.[show abstract] [hide abstract]
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. · 2.42 Impact Factor