See Appendix for the members of ESBL national surveillance working group.
Multi-centre evaluation of a phenotypic extended spectrum β-lactamase detection guideline in the routine setting
Version of Record online: 23 JAN 2012
© 2011 The Authors. Clinical Microbiology and Infection © 2011 European Society of Clinical Microbiology and Infectious Diseases
Clinical Microbiology and Infection
Volume 19, Issue 1, pages 70–76, January 2013
How to Cite
Platteel, T. N., Cohen Stuart, J. W., de Neeling, A. J., Voets, G. M., Scharringa, J., van de Sande, N., Fluit, A. C., Bonten, M. J. M., Leverstein-van Hall, M. A. and on behalf of the ESBL national surveillance working group (2013), Multi-centre evaluation of a phenotypic extended spectrum β-lactamase detection guideline in the routine setting. Clinical Microbiology and Infection, 19: 70–76. doi: 10.1111/j.1469-0691.2011.03739.x
- Issue online: 21 DEC 2012
- Version of Record online: 23 JAN 2012
- Accepted manuscript online: 26 NOV 2011 01:26AM EST
- Original Submission: 15 July 2011; Revised Submission: 4 November 2011; Accepted: 19 November 2011 Editor: R. Cantón
This study aimed to evaluate the routine setting performance of a guideline for phenotypic detection of extended spectrum β-lactamases (ESBLs) in Enterobacteriaceae, recommending ESBL confirmation with Etest or combination disc for isolates with a positive ESBL screen test (i.e. cefotaxime and/or ceftazidime MIC >1 mg/L or an automated system ESBL warning). Twenty laboratories submitted 443 Enterobacteriaceae with a positive ESBL screen test and their confirmation test result (74%Escherichia coli, 12%Enterobacter cloacae, 8%Klebsiella pneumoniae, 3%Proteus mirabilis, 2%Klebsiella oxytoca). Presence of ESBL genes was used as reference test. Accuracy of local phenotypic ESBL detection was 88%. The positive predictive value (PPV) of local screen tests was 70%, and differed per method (Vitek-2: 69%, Phoenix: 68%, disc diffusion: 92%), and species (95%K. pneumoniae-27%K. oxytoca). A low PPV (3%) was observed for isolates with automated system alarm but third-generation cephalosporin MICs <2 mg/L. Local ESBL confirmation had a PPV and negative predictive value (NPV) of 93% and 90%, respectively. Compared with centrally performed confirmation tests, 7% of local tests were misinterpreted. Combination disc was more specific than Etest (91% versus 61%). Confirmation tests were not reliable for P. mirabilis and K. oxytoca (PPV 33% and 38%, respectively, although NPVs were 100%). In conclusion, performance of Etests could be enhanced by education of technicians to improve their interpretation, by genotypic ESBL confirmation of P. mirabilis and K. oxytoca isolates with positive phenotypic ESBL confirmation, and by interpreting isolates with a positive ESBL alarm but an MIC <2 mg/L for cefotaxime and ceftazidime as ESBL-negative.