The emergence and worldwide spread of carbapenemase-producing  Enterobacteriaceae is of great concern to public health services. The aim of this study  was to investigate the occurrence of carbapenemase-producing Enterobacteriaceae in  the community in Switzerland.Findings: One thousand and eighty-six stool samples of  healthy humans (staff members of a food-processing company which were screened  for the occurrence of salmonellae) were collected in September 2014. After an initial  enrichment-step, carbapenemase-producing Enterobacteriaceae were isolated from  the carbapenem-containing selective medium SUPERCARBA II. Grown colonies from  11 samples were screened by PCR for the presence of bla KPC, bla NDM, bla OXA-48  and bla VIM. A single OXA-48-producing Escherichia coli was detected. Phylogenetic  grouping and multi-locus sequence typing (MLST) revealed that this strain belonged to  D:ST38, a type which had been previously reported in the UK, France, Lebanon and  Egypt.Conclusions: The results of this study show that OXA-48-producing  Enterobacteriaceae have started to spread into the community in Switzerland, and a  continuous monitoring is necessary to better understand their dissemination in the  human population as well as in animals and the environment

Hächler, Herbert

Nordmann, Patrice

Nüesch-Inderbinen, Magdalena T

Poirel, Laurent

Stephan, Roger

Zurfluh, Katrin

RERO DOC Digital Library

Zurfluh et al. Antimicrobial Resistance and Infection Control  (2015) 4:9 DOI 10.1186/s13756-015-0051-xSHORT REPORT Open AccessEmergence of Escherichia coli producing OXA-48β-lactamase in the community in SwitzerlandKatrin Zurfluh1, Magdalena T Nüesch-Inderbinen1, Laurent Poirel2, Patrice Nordmann2, Herbert Hächler1and Roger Stephan1*AbstractBackground: The emergence and worldwide spread of carbapenemase-producing Enterobacteriaceae is of greatconcern to public health services. The aim of this study was to investigate the occurrence of carbapenemase-producingEnterobacteriaceae in the community in Switzerland.Findings: One thousand and eighty-six stool samples of healthy humans (staff members of a food-processing companywhich were screened for the occurrence of salmonellae) were collected in September 2014. After an initialenrichment-step, carbapenemase-producing Enterobacteriaceae were isolated from the carbapenem-containingselective medium SUPERCARBA II. Grown colonies from 11 samples were screened by PCR for the presence of blaKPC,blaNDM, blaOXA-48 and blaVIM. A single OXA-48-producing Escherichia coli was detected. Phylogenetic grouping andmulti-locus sequence typing (MLST) revealed that this strain belonged to D:ST38, a type which had been previouslyreported in the UK, France, Lebanon and Egypt.Conclusions: The results of this study show that OXA-48-producing Enterobacteriaceae have started to spread into thecommunity in Switzerland, and a continuous monitoring is necessary to better understand their dissemination in thehuman population as well as in animals and the environment.Keywords: Carbapenemase, Community, Enterobacteriaceae, Dissemination, OXA-48FindingsMost carbapenemases identified in Enterobacteriaceaehydrolyze almost all β-lactam antibiotics, including car-bapenems, with the exception of OXA-48 that weaklyhydrolyses carbapenems but paradoxally spares broad-spectrum cephalosporins. Currently, the most prevalentcarbapenemases found among Enterobacteriaceae world-wide include the Ambler class A carbapenemase KPC,the class B metallo-β-lactamases (MBLs) of the IMP-,NDM- or VIM-type, and the class D OXA-48-like oxa-cillinases [1].Carbapenemase-producing Enterobacteriaceae (mainlyKlebsiella pneumoniae and Escherichia coli) were firstdescribed in Europe in the 1990s, and since then theyhave been increasingly reported especially in clinical set-tings. The emergence of these bacteria is of great con-cern to public health services because they are often also* Correspondence: stephanr@fsafety.uzh.ch1Institute for Food Safety and Hygiene, Vetsuisse Faculty University of Zurich,Winterthurerstrasse 272, 8057 Zurich, SwitzerlandFull list of author information is available at the end of the article© 2015 Zurfluh et al.; licensee BioMed CentralCommons Attribution License (http://creativecreproduction in any medium, provided the orDedication waiver (http://creativecommons.orunless otherwise stated.co-resistant to many other antibiotic classes and thus,only few treatment options remain [2]. Their dissemin-ation into the community and the environment is only amatter of time.Two years ago, we reported that there was no evidencefor the dissemination of carbapenemase-producing En-terobacteriaceae in the community in Switzerland [3].The aim of this study was to survey the current situationfor the presence of carbapenemase-producing Entero-bacteriaceae in healthy humans in Switzerland.In the context of a yearly routine fecal screening forsalmonellae, stool samples were obtained from 3200employees of a meat-processing company. This com-pany consists of eight countrywide processing plantsand employs people from the surrounding urban areas.Each staff member was tested only once. For this study,1086 samples were randomly selected. The samples weretested for the presence of KPC-, NDM-, OXA-48, or VIM-type carbapenemase-producing Enterobacteriaceae. Aloopful of each sample was enriched for 24 hours at 37°Cin 5 mL of Enterobacteriaceae Enrichment (EE) broth. This is an Open Access article distributed under the terms of the Creativeommons.org/licenses/by/4.0), which permits unrestricted use, distribution, andiginal work is properly credited. The Creative Commons Public Domaing/publicdomain/zero/1.0/) applies to the data made available in this article,Zurfluh et al. Antimicrobial Resistance and Infection Control  (2015) 4:9 Page 2 of 3without antibiotic (Oxoid, Ltd, Basingstoke, Hampshire,England). The enrichment culture was thereafter streakedonto a modified SUPERCARBA agar medium selecting forbacteria with reduced susceptibility to ertapenem, which isthe most sensitive marker for carbapenemase production.The SUPERCARBA II medium differs from the previouslypublished SUPERCARBA [4] since its basis is made ofTrypticase Soy agar (rather than Drigalski) and con-tains vancomycin (10 μg/ml) and amphotericin B(5 μg/ml) in order to prevent the growth of Gram pos-itives or fungi. SUPERCARBA, ideally complementedby the RAPIDEC® CARBA NP test (bioMérieux Ltd),has been shown to be most suited to detect carbape-nemase producers, since it exhibits a very high specifi-city and a very high sensitivity even for those OXA-48-producing strains that often exhibit low MICs ofcarbapenems [4].Growth of oxidase negative colonies was obtained foreleven selective plates and those colonies were screenedby PCR for the presence of blaKPC, blaNDM, blaOXA-48and blaVIM using primers described previously [5,6].Species identification using API ID 32 E (bioMérieux,Marcy l’Etoile, France) and multi-locus sequence typing[7] was performed with strains positive for any of theabove listed genes. Phylogenetic classification was per-formed as described previously [8].A single isolate (JU-S-791) was found positive for theblaOXA-48 carbapenemase gene (100% identity after se-quencing), which corresponded to a shedding prevalenceof carbapenemase-producing Enterobacteriaceae in thetested collective of 0.09%. The Oxa-48-positive individ-ual, a Turkish citizen born and raised in Switzerland,had no history of hospital admissions and no history ofrecent antibiotic therapy but reported annual visits toTurkey and a journey to Italy one month prior to sam-pling. The OXA-48 producer was identified as E. coli se-quence type (ST) 38 and belonged to the extraintestinalpathogenic phylogenetic group D.Susceptibility testing was performed by the agar diffu-sion method, using antibiotic disks (Becton Dickinsonand Company, Maryland, USA) according to the manu-facturers' protocols. Minimal inhibitory concentrations(MIC) of imipenem and cefotaxime, ceftazidime, and ce-fepime alone and in combination with clavulanic acidwere determined by Etest strips (bioMérieux, Marcyl’Etoile, France). Results were interpreted according tothe criteria of the Clinical and Laboratory Standards In-stitute (CLSI) [9].The MIC of imipenem was 0.5 μg/ml, which is stillbelow the susceptibility breakpoint defined by CLSI.Class D carbapenem-hydrolyzing β-lactamases possessweak carbapenemase-activity and usually do not confer ahigh-level resistance phenotype unless the strain exhibitsadditional permeability defects [10,11].Although OXA-48-producers only very poorlyhydrolyze expanded-spectrum cephalosporins, the strainJU-S-791 displayed an extended-spectrum β-lactamase(ESBL) phenotype (MIC of cefotaxime >16 μg/ml, andMIC of cefotaxime plus clavulanic acid = 0.5 μg/ml) andadditionally tested resistant in the disk diffusion test togentamicin (zone diameter 10 mm), nalidixic acid,(6.5 mm), sulfamethoxazole (6 mm) and trimethoprim(6 mm). It was susceptible in the disk diffusion test tociprofloxacin (27 mm), tetracycline (19 mm), chloram-phenicol (25 mm) and kanamycin (19 mm). Screeningfor blaCTX-M, blaSHV and blaTEM as described previously[12], revealed that the strain, in addition to the blaOXA-48 gene, co-harbored the ESBL gene blaCTX-M-24 and thenarrow-spectrum β-lactamase gene blaTEM-1. In order toevaluate whether the blaOXA-48 gene could be trans-ferred, conjugation experiments were performed using astandardized method for liquid mating techniques, asdescribed elsewhere [13]. However, they systematicallyfailed, suggesting a chromosomal location of this gene,and no further attempts at plasmid detection wereundertaken.OXA-48 was first described 2001 in a K. pneumoniaeisolate from a patient in Istanbul, Turkey. It is suggestedthat the main reservoirs of OXA-48-harbouring K. pneu-moniae and E. coli are in North African countries andTurkey [11]. Nowadays, OXA-48 producing Enterobacteri-aceae are widely disseminated throughout many Europeancountries and have led to several hospital outbreaks [11].In particular, the spread of the blaOXA-48 gene in commu-nity isolates but also in the environment has been demon-strated in Morocco [14,15]. The successful spread ofblaOXA-48 is linked to a single self-conjugative 62 kb IncL/M plasmid which was so far only identified in Enterobacte-riaceae [16]. More recently, a chromosomal location ofblaOXA-48 was reported from isolates in the UK, France,Egypt, Lebanon and Switzerland [17-19], not only amonghumans but also in fowl [20]. Interestingly, chromosomallocation of blaOXA-48 was mostly associated with E. coli D:ST38 co-harboring blaCTX-M-24 and blaTEM-1—the samestrain type described in this study. Considering these simi-larities, it is highly probable that the strain described in thisstudy also contains a chromosomally encoded blaOXA-48.In conclusion, our study demonstrates that the prevalenceof carbapenemase-producing Enterobacteriaceae in healthyhumans in Switzerland is 0.09% (95% CI = <0.0001-0.0057)and is associated with E. coli D:ST38. This particular strainhas previously been predominantly associated with clinicalsettings [18,19,21]. Our results strongly suggest that thisepidemic clone, harboring a non-transmissible blaOXA-48gene, is currently circulating among healthy humans. Not-ably, this further demonstrates that the problem of the dis-semination of blaOXA-48 positive isolates is not only relatedto the epidemicity of the widely identified plasmid pOXA-Zurfluh et al. Antimicrobial Resistance and Infection Control  (2015) 4:9 Page 3 of 348a [22] among different strain backgrounds, but includesthe dissemination of a single E. coli ST38 strain harboringthe blaOXA-48 gene on its chromosome. It is now even moreimportant that further studies are carried out in order tosurvey the dissemination of carbapenemase-producingenterobacterial strains in the population. As a strategyfor ensuring the detection of strains that exhibit lowMICs of carbapenems such as OXA-48-producers, theuse of the SUPERCARBA II may be considered highlyrecommendable.Competing interestsAn international patent form for the Supercarba medium has been filed onbehalf of INSERM Transfert (Paris, France) involving LP as PN as co-discoverers.Authors’ contributionsRS, LP, HH and MNI designed the study. KZ drafted the manuscript andcarried out the microbiological and molecular biological tests. All authorsread and approved the final manuscript.AcknowledgementsThis project was partially funded by the Swiss Federal Office of Public Health.Author details1Institute for Food Safety and Hygiene, Vetsuisse Faculty University of Zurich,Winterthurerstrasse 272, 8057 Zurich, Switzerland. 2Medical and MolecularMicrobiology Unit “Emerging Antibiotic Resistance”, Dept of Medicine,Faculty of Science, University of Fribourg, Fribourg, Switzerland.Received: 21 January 2015 Accepted: 16 March 2015References1. Cantón R, Akóva M, Carmeli Y, Giske CG, Glupczynski Y, Gniadowski M, et al.Rapid evolution and spread of carbapenemases among Enterobacteriaceaein Europe. Clin Microbiol Infect. 2012;18:413–31.2. Grundmann H, Livermore DM, Giske CG, Canton R, Rossolini GM, Campos J,et al. Carbapenem-non-susceptible Enterobacteriaceae in Europe: conclu-sions from a meeting of national experts. Euro Surveill. 2010;15:1–13.3. Nüesch-Inderbinen M, Zurfluh K, Hächler H, Stephan R. No evidence so farfor the dissemination of carbapenemase-producing Enterobactericeae inthe community in Switzerland. Antimicrob Resist Infect Control. 2013;2:23.4. Nordmann P, Girlich D, Poirel L. Detection of carbapenemase producers inEnterobacteriaceae by use of a novel screening medium. J Clin Microbiol.2012;50:2761–6.5. Ellington MJ, Kistler J, Livermore DM, Woodford N. Multiplex PCR for rapiddetection of genes encoding acquired metallo-beta-lactamases.J Antimicrob Chemother. 2007;59:321–2.6. Poirel L, Walsh TR, Cuvillier V, Nordmann P. Multiplex PCR for detection ofacquired carbapenemase genes. Diagn Microbiol Infect Dis. 2011;70:119–23.7. Wirth T, Falush D, Lan R, Colles F, Mensa P, Wieler LH, et al. Sex andvirulence in Escherichia coli: an evolutionary perspective. Mol Microbiol.2006;60:1136–51.8. Clermont O, Bonacorsi S, Bingen E. Rapid and simple determination of theEscherichia coli phylogenetic group. Appl Env Microbiol. 2000;66:4555–8.9. Clinical and Laboratory Standarts Institute. Performance Standards forAntimicrobial Susceptibility Testing: Twenty-First Informational Supplement.CLSI document M100–S23. Wayne, PA 19087 USA: The Clinical andLaboratory Standarts Institute; 2013.10. Evans BA, Amyes SGB. OXA β-lactamases. Clin Microbiol Rev.2014;27:241–63.11. Nordmann P, Poirel L. The difficult-to-control spread of carbapenemaseproducers among Enterobacteriaceae worldwide. Clin Microbiol Infect.2014;20:821–30.12. Geser N, Stephan R, Hächler H. Occurrence and characteristics ofextended- spectrum β-lactamase (ESBL) producing Enterobacteriaceae infood producing animals, minced meat and raw milk. BMC Vet Res.2012;8:21.13. Zurfluh K, Jakobi G, Stephan R, Hächler H, Nüesch-Inderbinen M. Replicontyping of plasmids carrying blaCTX-M-1 in Enterobacteriaceae of animal,environmental and human origin. Front Microbiol. 2014;5:555.14. Potron A, Poirel L, Bussy F, Nordmann P. Occurrence of thecarbapenem-hydrolyzing β-lactamase gene blaOXA-48 in the environment inMorocco. Antimicrob Agents Chemother. 2011;55:5413–4.15. Girlich D, Bouihat N, Poirel L, Benouda A, Nordmann P. High rate of faecalcarriage of extended-spectrum β-lactamase and OXA-48carbapenemase-producing Enterobacteriaceae at a university hospital inMorocco. Clin Microbiol Infect. 2014;20:350–4.16. Poirel L, Potron A, Nordmann P. OXA-48-like carbapenemases: the phantommenace. J Antimicrob Chemother. 2012;67:1597–606.17. Potron A, Poirel L, Rondinaud E, Nordmann P: Intercontinental spread ofOXA-48 beta-lactamase-producing Enterobacteriaceae over a 11-year period,2001 to 2011. Euro Surveill. 2013;18(31). (http://www.eurosurveillance.org/ViewArticle.aspx?ArticleId=20549)18. Dimou V, Dhanji H, Pike R, Livermore DM, Woodford N. Characterization ofEnterobacteriaceae producing OXA-48-like carbapenemases in the UK. JAntimicrob Chemother. 2012;67:1660–5.19. Beyrouthy R, Robin F, Dabboussi F, Mallat H, Hamzé M, Bonnet R.Carbapenemase and virulence factors of Enterobacteriaceae in NorthLebanon between 2008 and 2012: evolution via endemic spread of OXA-48.J Antimicrob Chemother. 2014;69:2699–705.20. Al Bayssari C, Olaitan AO, Dabboussi F, Hamze M, Rolain JM. Emergence ofOXA-48-producing Escherichia coli clone ST38 in fowl. Antimicrob AgentsChemother. 2015;59:745–6.21. Poirel L, Bernabeu S, Fortineau N, Podglajen I, Lawrence C, Nordmann P.Emergence of OXA-48-producing Escherichia coli clone ST38 in France.Antimicrob Agents Chemother. 2011;55:4937–8.22. Potron A, Poirel L, Nordmann P. Derepressed transfer properties leading tothe efficient spread of the plasmid encoding carbapenemase OXA-48.Antimicrob Agents Chemother. 2014;58:467–71.Submit your next manuscript to BioMed Centraland take full advantage of: • Convenient online submission• Thorough peer review• No space constraints or color ﬁgure charges• Immediate publication on acceptance• Inclusion in PubMed, CAS, Scopus and Google Scholar• Research which is freely available for redistributionSubmit your manuscript at www.biomedcentral.com/submit

Emergence of Escherichia coli producing OXA-48 β-lactamase in the community in Switzerland

Abstract

Similar works

Full text

Available Versions

RERO DOC Digital Library