Development of the EUCAST disk diffusion antimicrobial susceptibility testing method and its implementation in routine microbiology laboratories

Matuschek, Erika; Brown, Derek F. J.; Kahlmeter, Gunnar

doi:10.1111/1469-0691.12373

Cited by 601 publications

(479 citation statements)

References 9 publications

Supporting

Mentioning

430

Contrasting

Unclassified

Order By: Relevance

“…A numerical definition of enhancement was not specified in their study. Many factors affect the zone of inhibition during disk diffusion studies, including variations in the culture media; the preparation and handling of inoculum suspensions, inoculated plates, and antimicrobial disks; the duration of incubation of the plates; and the reading of zones (19). A natural variation of 1 to 2.4 mm was described in previous studies (19,20).…”

Section: Discussionmentioning

confidence: 99%

Synergy of β-Lactams with Vancomycin against Methicillin-Resistant Staphylococcus aureus: Correlation of Disk Diffusion and Checkerboard Methods

Huang

Chen

et al. 2016

J Clin Microbiol

View full text Add to dashboard Cite

Modified disk diffusion (MDD) and checkerboard tests were employed to assess the synergy of combinations of vancomycin and ␤-lactam antibiotics for 59 clinical isolates of methicillin-resistant Staphylococcus aureus (MRSA) and Mu50 (ATCC 700699).Bacterial inocula equivalent to 0.5 and 2.0 McFarland standard were inoculated on agar plates containing 0, 0.5, 1, and 2 g/ml of vancomycin. Oxacillin-, cefazolin-, and cefoxitin-impregnated disks were applied to the surface, and the zones of inhibition were measured at 24 h. The CLSI-recommended checkerboard method was used as a reference to detect synergy. The MICs for vancomycin were determined using the Etest method, broth microdilution, and the Vitek 2 automated system. Synergy was observed with the checkerboard method in 51% to 60% of the isolates when vancomycin was combined with any ␤-lactam. The fractional inhibitory concentration indices were significantly lower in MRSA isolates with higher vancomycin MIC combinations (P < 0.05). The overall agreement between the MDD and checkerboard methods to detect synergy in MRSA isolates with bacterial inocula equivalent to McFarland standard 0.5 were 33.0% and 62.5% for oxacillin, 45.1% and 52.4% for cefazolin, and 43.1% and 52.4% for cefoxitin when combined with 0.5 and 2 g/ml of vancomycin, respectively. Based on our study, the simple MDD method is not recommended as a replacement for the checkerboard method to detect synergy. However, it may serve as an initial screening method for the detection of potential synergy when it is not feasible to perform other labor-intensive synergy tests.V ancomycin and other glycopeptide antibiotics are currently the standard treatment for methicillin-resistant Staphylococcus aureus (MRSA) (1). The emergence of MRSA with reduced vancomycin susceptibility (SA-RVS) raises concerns about the reliability of vancomycin for the treatment of MRSA (2). Resistance during treatment with daptomycin has raised similar concerns about its effectiveness for life-threatening MRSA infections (3). Low serum levels and the bacteriostatic activity of tigecycline against MRSA limit its use for the treatment of MRSA bacteremia (4).The combination of vancomycin and ␤-lactam antibiotics offers a potential option for management of MRSA infections (5). This concept is based on several in vitro and animal studies that demonstrated a synergistic effect of vancomycin-␤-lactam combinations against MRSA (6-11).The current study was designed to determine the utility of a modified disk diffusion (MDD) test to assess synergy and antagonism for combinations of vancomycin and ␤-lactam antibiotics among clinical isolates of MRSA (8, 12). The CLSI checkerboard method was used as the reference for the determination of synergy. We determined the vancomycin MIC breakpoint where synergy is most commonly observed in MRSA isolates. MATERIALS AND METHODSBacterial isolates. Fifty-nine unique clinical isolates of MRSA with vancomycin MICs of Ն0.5 g/ml were obtained from patients at the Kaohsiung Veterans General Hospital in Taiwan ...

show abstract

Section: Discussionmentioning

confidence: 99%

Synergy of β-Lactams with Vancomycin against Methicillin-Resistant Staphylococcus aureus: Correlation of Disk Diffusion and Checkerboard Methods

Huang

Chen

et al. 2016

J Clin Microbiol

View full text Add to dashboard Cite

show abstract

“…Phenotypic antibiotic susceptibility tests (ASTs) are typically based on the detection of differential bacterial growth with and without antibiotics in liquid cultures or on solid agar plates (4). In liquid tests, detection is based on the change in OD, whereas the disk diffusion method is used on solid agar plates to identify inhibition zones (5). These methods are generally reliable for detecting resistance and determining the antibiotic concentration that prevents bacterial growth, making them predictive of the therapeutic utility of different antibiotics.…”

mentioning

confidence: 99%

Antibiotic susceptibility testing in less than 30 min using direct single-cell imaging

Baltekin

Boucharin

Tano

et al. 2017

Proc. Natl. Acad. Sci. U.S.A.

324

344

View full text Add to dashboard Cite

The emergence and spread of antibiotic-resistant bacteria are aggravated by incorrect prescription and use of antibiotics. A core problem is that there is no sufficiently fast diagnostic test to guide correct antibiotic prescription at the point of care. Here, we investigate if it is possible to develop a point-of-care susceptibility test for urinary tract infection, a disease that 100 million women suffer from annually and that exhibits widespread antibiotic resistance. We capture bacterial cells directly from samples with low bacterial counts (10 4 cfu/mL) using a custom-designed microfluidic chip and monitor their individual growth rates using microscopy. By averaging the growth rate response to an antibiotic over many individual cells, we can push the detection time to the biological response time of the bacteria. We find that it is possible to detect changes in growth rate in response to each of nine antibiotics that are used to treat urinary tract infections in minutes. In a test of 49 clinical uropathogenic Escherichia coli (UPEC) isolates, all were correctly classified as susceptible or resistant to ciprofloxacin in less than 10 min. The total time for antibiotic susceptibility testing, from loading of sample to diagnostic readout, is less than 30 min, which allows the development of a point-of-care test that can guide correct treatment of urinary tract infection.point of care | UTI | AST | antibiotic | resistance | microfluidic

show abstract

“…Kekeruhan yang diperoleh kemudian disetarakan dengan larutan standar Mc Farland 0,5 yaitu setara dengan jumlah pertumbuhan 1-2 10 8 CFU/mL (Matuschek et al, 2013).…”

Section: Pembuatan Inokulum Bakteri S Aureusunclassified

Determination of FICI of Ethanolic Extract of Aloe Vera Skin Leaves (Aloe vera (L.) Burm.f.) and Gentamicin Sulphate againts Staphylococcus aureus

2017

View full text Add to dashboard Cite

show abstract

Development of the EUCAST disk diffusion antimicrobial susceptibility testing method and its implementation in routine microbiology laboratories

Cited by 601 publications

References 9 publications

Synergy of β-Lactams with Vancomycin against Methicillin-Resistant Staphylococcus aureus: Correlation of Disk Diffusion and Checkerboard Methods

Synergy of β-Lactams with Vancomycin against Methicillin-Resistant Staphylococcus aureus: Correlation of Disk Diffusion and Checkerboard Methods

Antibiotic susceptibility testing in less than 30 min using direct single-cell imaging

Determination of FICI of Ethanolic Extract of Aloe Vera Skin Leaves (Aloe vera (L.) Burm.f.) and Gentamicin Sulphate againts Staphylococcus aureus

Contact Info

Product

Resources

About