Loading...
Publication
Carbapenemase-producing multidrug resistant Enterobacteriaceae in Portugal: class A and B
| Name: | Description: | Size: | Format: | |
|---|---|---|---|---|
| 74.31 KB | Adobe PDF |
Advisor(s)
Abstract(s)
Introduction: Carbapenems are often the antimicrobials of last resort to treat infections due to extended-spectrum β-lactamase (ESBL)- or plasmid-mediated AmpC (PMAβ)-producing Enterobacteriaceae isolates. Unfortunately, carbapenem non-susceptible Enterobacteriaceae have been reported worldwide mainly, because of the acquisition of carbapenemase-encoding genes. A large variety of carbapenemases has increasingly been identified in each of the four Ambler molecular classes. Thus, the main aim of this study was to search and characterize carbapenemase-producing Enterobacteriaceae (CPE) isolates recovered from Portuguese health care institutions.
Methods: This study included 165 clinical isolates of Enterobacteriaceae nonsusceptible to ertapenem, identified among 2105 isolates, all recovered from different Portuguese healthcare institutions, between 2006 and 2013 that were sent to the NIH for antibiotic susceptibility confirmation in the context of its reference function. Screening of antimicrobial susceptibility was performed by disc diffusion method (www.sfm-microbiologie.org/). Clinical isolates with resistance or with decreased susceptibility to ertapenem were considered putative carbapenemase producers. For all CPE isolates and respective transconjugants, MICs of selected antibiotics were determined by the microdilution broth method (http://www.eucast.org/clinical_breakpoints/).
PCR and sequencing were applied to detect and identify the main CPE-encoding genes from class A, B and/or D. The presence of blaESBL, blaPMAβ, and PMQR-encoding genes, were also investigated. Transferability of the carbapenemase genes was attended by broth mating-out assays. The plasmids obtained from transconjugants were characterized by PCR-based replicon typing. Genetic diversity of K. pneumoniae isolates was investigated by multilocus sequence typing (MLST), using the protocol developed by the Institute Pasteur (www.pasteur.fr/mlst/Kpneumoniae.html).
Results:
Thirty-five (21.2%) of the 165 positive isolates were confirmed to be CPE, of which the majority were collected from the urine (54.3%) of elderly (≥65 years old) male patients (54.3%), and admitted at the emergency room/ambulatory (22.9%) or internal medicine (17.1%) wards. All were multidrug-resistant with nonsusceptibility to at least one carbapenem; colistin was the only antibiotic effective against all CPE isolates. Tigecycline and ciprofloxacin were effective against 57.1% and 31.4%, respectively, of carbapenemase-producing isolates. We identify 30 blaKPC-3, 4 blaGES-5 and one blaVIM-2, alone or in combination with other bla and/or PMQR-encoding genes. MLST of the 30 K. pneumoniae isolates showed an important diversity, belonging to distinct STs.
Conclusion: This study provides new data regarding the widespread of CPE in Portugal, which encoding genes are carried by similar plasmids. Overall, our results emphasize the need of a concerted action to manage carbapenem use.
Description
Keywords
Resistência aos Antibióticos CPE Carbapenemases Portugal
Pedagogical Context
Citation
Caniça, M., Manageiro, V., Almeida, J., Barbosa, S., Simões, C., Ferreira, E. 2014. Carbapenemase-producing multidrug resistant Enterobacteriaceae in Portugal: class A and B. 12th β-Lactamase Meeting. Gran Canaria, Canary Islands, Spain.