Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2014 Sep 3:7:603.
doi: 10.1186/1756-0500-7-603.

Impact of minimal inhibitory concentration breakpoints on local cumulative bacterial susceptibility data and antibiotic consumption

Sofia Stokkou, Ina Tammer, Stefanie Zibolka, Christina Grabau, Gernot Geginat  1
Affiliations

Impact of minimal inhibitory concentration breakpoints on local cumulative bacterial susceptibility data and antibiotic consumption

Sofia Stokkou et al. BMC Res Notes. .

Abstract

Background: The phenotypic antimicrobial susceptibility testing (AST) of bacteria depends on minimal inhibitory concentration breakpoints issued by national and international breakpoint committees. The current study was performed in order to test the influence of different AST standards on local cumulative AST data and on antibiotic consumption.

Methods: Automated AST was performed with clinical isolates of Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Staphylococcus aureus, coagulase-negative staphylococci, Enterococcus faecalis, and E. faecium. From each species 100 prospectively collected non-duplicate clinical isolates were tested and MIC data were interpreted according to the interpretation standards issued by DIN and EUCAST, respectively. In addition cumulative AST data from clinical isolates and antibiotic consumption were monitored before and after implementation of new EUCAST MIC breakpoints.

Results: The susceptibility rate of P. aeruginosa against piperacillin and gentamicin, and of C. freundii against piperacillin/tazobactam increased significantly, whereas the susceptibility rates of E. cloacae, S. marcescens, and M. morganii against ciprofloxacin decreased significantly after switching from DIN to EUCAST MIC breakpoints. These changes in the cumulative antibiotic resistance pattern were reflected by enhanced consumption of piperacillin/tazobactam after implementation of EUCAST MIC breakpoints.

Conclusions: These data show that changes of AST breakpoints have a significant influence on local cumulative AST data and on antibiotic consumption.

PubMed Disclaimer

Figures

Figure 1
Figure 1
Antibiotic consumption of selected antibiotics before and after implementation of EUCAST MIC breakpoints. The prescribed defined daily doses per 1000 patient days was calculated for the study periods of 12 month before (open bars) and 12 month after (closed bars) implementation of EUCAST MIC breakpoints. Indicated are the means and standard deviations of the 4 quarters before and the 4 quarters after implementation of EUCAST MIC breakpoints. The asterisk indicates a statistically significant (p < 0.05) change of antibiotic consumption.
See this image and copyright information in PMC

References

    1. Normensausschuss Medizin im DIN . Teil 4: Bewertungsstufen für die Minimale Hemmkonzentration; MHK-Grenzwerte von Antibakteriellen Wirkstoffen. In: Normung DDIf., editor. Medizinische Mikrobiologie- Empfindlichkeitsprüfung von Mikrobiellen Krankheitserregern Gegen Chemotherapeutika. Berlin, Germany: Beuth Verlag GmbH; 2004.
    1. Breakpoint tables for interpretation of MICs and zone diameters, version 2.0http://www.eucast.org/fileadmin/src/media/PDFs/EUCAST_files/Breakpoint_t...
    1. Clinical and Laboratory Standards Institute . Performance Standards for Antimicrobial Susceptibility Testing: Twentieth Informational Supplement. M100-S20. Wayne, PA, USA: CLSI; 2010.
    1. Dellit TH, Owens RC, McGowan JE, Jr, Gerding DN, Weinstein RA, Burke JP, Huskins WC, Paterson DL, Fishman NO, Carpenter CF, Brennan PJ, Billeter M, Hooton TM. Infectious diseases society of America and the society for healthcare epidemiology of America guidelines for developing an institutional program to enhance antimicrobial stewardship. Clin Infect Dis. 2007;44(2):159–177. doi: 10.1086/510393. - DOI - PubMed
    1. Magiorakos AP, Srinivasan A, Carey RB, Carmeli Y, Falagas ME, Giske CG, Harbarth S, Hindler JF, Kahlmeter G, Olsson-Liljequist B, Paterson DL, Rice LB, Stelling J, Struelens MJ, Vatopoulos A, Weber JT, Monnet DL. Multidrug-resistant, extensively drug-resistant and pandrug-resistant bacteria: an international expert proposal for interim standard definitions for acquired resistance. Clin Microbiol Infect. 2012;18(3):268–281. doi: 10.1111/j.1469-0691.2011.03570.x. - DOI - PubMed

MeSH terms

Substances