1887

Abstract

AmpC β-lactamases (Bla) are an emerging group of antimicrobial resistance determinants. The lack of an agreed Bla detection method hinders investigation of their epidemiology and understanding of their clinical significance. This study compared the sensitivity and specificity of phenotypic methods of Bla detection in a collection of 246 with a diverse range of β-lactam resistance profiles. The Bla screening methods evaluated were based on cephamycin, ceftazidime and cefepime susceptibility. These were compared with Bla screening using conventional ESBL detection methods. The confirmatory methods evaluated were biologically based assays, inhibitor-based assays, an AmpC Etest and a rapid chromogenic assay. A multiplex nucleic acid amplification test and the three-dimensional enzyme extraction assay were used as reference methods. Bla activity was present in 74 isolates. The majority of the enzymes were plasmid-encoded and belonged to the CMY, DHA and EBC families. The screening methods had sensitivities between 47 and 99 % and specificities of 45–95 %. The performance of confirmatory tests varied widely, ranging in sensitivity from 19 % to 97 % and in specificity from 88 % to 100 %. Only the Tris-EDTA and MAST ID D68C disc tests had a sensitivity and a specificity above 90 %. Further investigation is needed to establish the most suitable enzyme substrates, inhibitor types, inhibitor concentrations and interpretative cut-offs in order to refine the inhibitor-based methods. A simple disc-based protocol using cefoxitin non-susceptibility as a screening tool, followed by the Tris-EDTA method for confirmation, detects Bla activity with 95 % sensitivity and 98 % specificity.

Loading

Article metrics loading...

/content/journal/jmm/10.1099/jmm.0.029140-0
2011-06-01
2024-04-18
Loading full text...

Full text loading...

/deliver/fulltext/jmm/60/6/715.html?itemId=/content/journal/jmm/10.1099/jmm.0.029140-0&mimeType=html&fmt=ahah

References

  1. Alvarez M., Tran J. H., Chow N., Jacoby G. A. 2004; Epidemiology of conjugative plasmid-mediated AmpC beta-lactamases in the United States. Antimicrob Agents Chemother 48:533–537 [View Article][PubMed]
    [Google Scholar]
  2. Black J. A., Moland E. S., Thomson K. S. 2005a; AmpC disk test for detection of plasmid-mediated AmpC beta-lactamases in Enterobacteriaceae lacking chromosomal AmpC beta-lactamases. J Clin Microbiol 43:3110–3113 [View Article][PubMed]
    [Google Scholar]
  3. Black J. A., Thomson K. S., Buynak J. D., Pitout J. D. 2005b; Evaluation of beta-lactamase inhibitors in disk tests for detection of plasmid-mediated AmpC beta-lactamases in well-characterized clinical strains of Klebsiella spp. J Clin Microbiol 43:4168–4171 [View Article][PubMed]
    [Google Scholar]
  4. Brenwald N. P., Jevons G., Andrews J., Ang L., Fraise A. P. 2005; Disc methods for detecting AmpC β-lactamase-producing clinical isolates of Escherichia coli and Klebsiella pneumoniae. J Antimicrob Chemother 56:600–601 [View Article][PubMed]
    [Google Scholar]
  5. CLSI (2009). Methods for Dilution Antimicrobial Susceptibility Tests for Bacteria that Grow Aerobically, M7-A8. Wayne, PA: Clinical Laboratory Standards Institute
  6. CLSI (2010). Performance Standards for Antimicrobial Susceptibility Testing, M100-S20. Wayne, PA: Clinical and Laboratory Standards Institute
  7. Coudron P. E. 2005; Inhibitor-based methods for detection of plasmid-mediated AmpC beta-lactamases in Klebsiella spp., Escherichia coli, and Proteus mirabilis. J Clin Microbiol 43:4163–4167 [View Article][PubMed]
    [Google Scholar]
  8. Coudron P. E., Moland E. S., Thomson K. S. 2000; Occurrence and detection of AmpC β-lactamases among Escherichia coli, Klebsiella pneumoniae, and Proteus mirabilis isolates at a veterans medical center. J Clin Microbiol 38:1791–1796[PubMed]
    [Google Scholar]
  9. Ding H., Yang Y., Lu Q., Wang Y., Chen Y., Deng L., Wang A., Deng Q., Zhang H. et al. 2008; The prevalence of plasmid-mediated AmpC beta-lactamases among clinical isolates of Escherichia coli and Klebsiella pneumoniae from five children’s hospitals in China. Eur J Clin Microbiol Infect Dis 27:915–921 [View Article][PubMed]
    [Google Scholar]
  10. Doi Y., Paterson D. L. 2007; Detection of plasmid-mediated class C beta-lactamases. Int J Infect Dis 11:191–197 [View Article][PubMed]
    [Google Scholar]
  11. Ellem J., Thomas L., Olma T., Iredell J. 2009a; Comparison and evaluation of a newly developed Mast 4-Disc test for the detection of plasmid-mediated AmpC beta-lactamases. In Australian Society for Antimicrobials Conference, Sydney, Australia Abstract no. P2.3
    [Google Scholar]
  12. Ellem J., Thomas L., Olma T., Iredell J. 2009b; Rapid detection of AmpC beta-lactamases by multiplex real-time PCR and melt curve analysis. In Australian Society for Antimicrobials Conference, Sydney, Australia Abstract no. P2.4
    [Google Scholar]
  13. Giske C. G., Sundsfjord A. S., Kahlmeter G., Woodford N., Nordmann P., Paterson D. L., Cantón R., Walsh T. R. 2009; Redefining extended-spectrum beta-lactamases: balancing science and clinical need. J Antimicrob Chemother 63:1–4 [View Article][PubMed]
    [Google Scholar]
  14. Hope R., Warner M., Livermore D. M. 2008; Phenotypic AmpC detection – which inhibitor is best?. In 18th European Congresses of Clinical Microbiology and Infectious Diseases Conference, Barcelona, Spain Abstract no. P876
    [Google Scholar]
  15. Jacoby G. A. 2009; AmpC beta-lactamases. Clin Microbiol Rev 22:161–182 [View Article][PubMed]
    [Google Scholar]
  16. Kohner P. C., Robberts F. J., Cockerill F. R. III, Patel R. 2009; Cephalosporin MIC distribution of extended-spectrum-beta-lactamase- and pAmpC-producing Escherichia coli and Klebsiella species. J Clin Microbiol 47:2419–2425 [View Article][PubMed]
    [Google Scholar]
  17. Livermore D. M. 1995; β-Lactamases in laboratory and clinical resistance. Clin Microbiol Rev 8:557–584[PubMed]
    [Google Scholar]
  18. Livermore D. M., Warner M., Mushtaq S. 2007; Evaluation of the chromogenic Cica-β-Test for detecting extended-spectrum, AmpC and metallo-β-lactamases. J Antimicrob Chemother 60:1375–1379 [View Article][PubMed]
    [Google Scholar]
  19. Moland E. S., Black J. A., Ourada J., Reisbig M. D., Hanson N. D., Thomson K. S. 2002; Occurrence of newer beta-lactamases in Klebsiella pneumoniae isolates from 24 U.S. hospitals. Antimicrob Agents Chemother 46:3837–3842 [View Article][PubMed]
    [Google Scholar]
  20. Montgomery J., Nakos J., Gurtler V. 2008; Comparison of phenotypic tests for detection of plasmid-mediated AmpC beta-lactamases. In Australian Society for Antimicrobials Conference, Sydney, Australia Abstract no. P2.2
    [Google Scholar]
  21. Mulvey M. R., Bryce E., Boyd D. A., Ofner-Agostini M., Land A. M., Simor A. E., Paton S. 2005; Molecular characterization of cefoxitin-resistant Escherichia coli from Canadian hospitals. Antimicrob Agents Chemother 49:358–365 [View Article][PubMed]
    [Google Scholar]
  22. Munier G. K., Johnson C. L., Snyder J. W., Moland E. S., Hanson N. D., Thomson K. S. 2010; Positive extended-spectrum-beta-lactamase (ESBL) screening results may be due to AmpC beta-lactamases more often than to ESBLs. J Clin Microbiol 48:673–674 [View Article][PubMed]
    [Google Scholar]
  23. Nakano R., Okamoto R., Nakano Y., Kaneko K., Okitsu N., Hosaka Y., Inoue M. 2004; CFE-1, a novel plasmid-encoded AmpC β-lactamase with an ampR gene originating from Citrobacter freundii. Antimicrob Agents Chemother 48:1151–1158 [View Article][PubMed]
    [Google Scholar]
  24. Pérez-Pérez F. J., Hanson N. D. 2002; Detection of plasmid-mediated AmpC beta-lactamase genes in clinical isolates by using multiplex PCR. J Clin Microbiol 40:2153–2162 [View Article][PubMed]
    [Google Scholar]
  25. Philippon A., Arlet G., Jacoby G. A. 2002; Plasmid-determined AmpC-type beta-lactamases. Antimicrob Agents Chemother 46:1–11 [View Article][PubMed]
    [Google Scholar]
  26. Robberts F. J. L., Kohner P. C., Patel R. 2009; Unreliable extended-spectrum β-lactamase detection in the presence of plasmid-mediated AmpC in Escherichia coli clinical isolates. J Clin Microbiol 47:358–361 [View Article][PubMed]
    [Google Scholar]
  27. Senda K., Arakawa Y., Ichiyama S., Nakashima K., Ito H., Ohsuka S., Shimokata K., Kato N., Ohta M. 1996; PCR detection of metallo-β-lactamase gene (blaIMP) in gram-negative rods resistant to broad-spectrum β-lactams. J Clin Microbiol 34:2909–2913[PubMed]
    [Google Scholar]
  28. Sidjabat H. E., Paterson D. L., Qureshi Z. A., Adams-Haduch J. M., O’Keefe A., Pascual A., Rodríguez-Baño J., Doi Y. 2009; Clinical features and molecular epidemiology of CMY-type beta-lactamase-producing Escherichia coli. Clin Infect Dis 48:739–744 [View Article][PubMed]
    [Google Scholar]
  29. Singhal S., Mathur T., Khan S., Upadhyay D. J., Chugh S., Gaind R., Rattan A. 2005; Evaluation of methods for AmpC beta-lactamase in gram negative clinical isolates from tertiary care hospitals. Indian J Med Microbiol 23:120–124 [View Article][PubMed]
    [Google Scholar]
  30. Tan T. Y., Ng S. Y., Teo L., Koh Y., Teok C. H. 2008; Detection of plasmid-mediated AmpC in Escherichia coli, Klebsiella pneumoniae and Proteus mirabilis. J Clin Pathol 61:642–644 [View Article][PubMed]
    [Google Scholar]
  31. Tan T. Y., Ng L. S., He J., Koh T. H., Hsu L. Y. 2009; Evaluation of screening methods to detect plasmid-mediated AmpC in Escherichia coli, Klebsiella pneumoniae, and Proteus mirabilis. Antimicrob Agents Chemother 53:146–149 [View Article][PubMed]
    [Google Scholar]
  32. Tenover F. C., Emery S. L., Spiegel C. A., Bradford P. A., Eells S., Endimiani A., Bonomo R. A., McGowan J. E. Jr 2009; Identification of plasmid-mediated AmpC beta-lactamases in Escherichia coli, Klebsiella spp., and Proteus species can potentially improve reporting of cephalosporin susceptibility testing results. J Clin Microbiol 47:294–299 [View Article][PubMed]
    [Google Scholar]
  33. Thomson K. S. 2010; Extended-spectrum-beta-lactamase, AmpC, and carbapenemase issues. J Clin Microbiol 48:1019–1025 [View Article][PubMed]
    [Google Scholar]
  34. Yagi T., Wachino J., Kurokawa H., Suzuki S., Yamane K., Doi Y., Shibata N., Kato H., Shibayama K., Arakawa Y. 2005; Practical methods using boronic acid compounds for identification of class C beta-lactamase-producing Klebsiella pneumoniae and Escherichia coli. J Clin Microbiol 43:2551–2558 [View Article][PubMed]
    [Google Scholar]
  35. Yong D., Park R., Yum J. H., Lee K., Choi E. C., Chong Y. 2002; Further modification of the Hodge test to screen AmpC beta-lactamase (CMY-1)-producing strains of Escherichia coli and Klebsiella pneumoniae. J Microbiol Methods 51:407–410 [View Article][PubMed]
    [Google Scholar]
http://instance.metastore.ingenta.com/content/journal/jmm/10.1099/jmm.0.029140-0
Loading
/content/journal/jmm/10.1099/jmm.0.029140-0
Loading

Data & Media loading...

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error