ETEST® Ceftazidime/Avibactam (CZA 256)

Test strip for MIC determination of ceftazidime/avibactam

NEW test strips provide Minimum Inhibitory Concentration (MIC) level for antimicrobial susceptibility of Gram-negative bacteria such as Enterobacteriaceae and P. aeruginosa. This information helps support appropriate antimicrobial therapy decisions for better patient outcomes and contributes to antimicrobial stewardship.

  • Reliably monitor susceptibility to ceftazidime/ avibactam (Avycaz**/ Zavicefta***)
  • Antimicrobial susceptibility determination in as little as 16 hours
  • Determines exact MIC values
Add to your selection

Do you need more information?

Antimicrobial resistance: Why responsible treatment is critical

Antimicrobial resistance is one of today’s top healthcare concerns worldwide. With the development of Multi-drug Resistant Organisms (MDRO), particularly Gram-negative bacteria, even infections that were once easy to treat can be life-threatening1Antimicrobial stewardship – appropriate selection and use of antimicrobials – helps improve patient outcomes, prevent resistance development and preserve the effectiveness of new antimicrobials like the ceftazidime/avibactam combination drug. In this context, it’s important for clinicians to have clear and reliable information to make the best decisions for antibiotic therapy – before, during and after treatment. A key part of this is accurate and rapid antimicrobial susceptibility testing – for ceftazidime/avibactam, there’s now ETEST® Ceftazidime/Avibactam (CZA 256)

How can ETEST® CZA 256 strips help?

ETEST® Ceftazidime/Avibactam (CZA 256) strips determine exact Minimum Inhibitory Concentration (MIC) values to assess susceptibility to ceftazidime/avibactam, a new treatment developed to treat some serious infections for which few effective therapies exist1,2,3. Known by the trade name Avycaz** in the U.S. and Zavicefta*** elsewhere, ceftazidime/avibactam acts on Gram-negative bacteria and is indicated for complicated intra-abdominal infections (cIAI) in combination with metronidazole, as well as for the treatment of complicated urinary tract infections (cUTI), including acute pyelonephritis (AP), in patients over 18.  Zavicefta is also approved for hospital-acquired pneumonia including ventilator associated pneumonia outside of the United States.

Exact MICs: Real precision in ETEST® CZA 256

Thanks to the determination of exact MIC values, ETEST® CZA 256 strips offer greater precision than conventional two-fold dilutions (i.e. half dilutions) with interpretive category (S, I, R). In as little as 16 hours incubation, you can determine how susceptible the organism is, not just if it is susceptible. This information helps clinicians make informed patient-care decisions for ceftazidime/avibactam therapy and reduce the risk of development of drug-resistant bacteria. Epidemiological tracking of evolution of infectious organisms is also possible with MIC values, helping detect emergence of resistance over time.

ETEST®: Easy, effective and precise

The new ETEST® CZA 256 strips are the latest addition to the ETEST® range – the original gradient strips – which are widely documented for their effectiveness and precision.

Comprised of a MIC reading scale and an antibiotic gradient, ETEST® strips are processed in a similar manner to diffusion methods. They differ in that the antimicrobial concentration gradient is preformed, predefined and stable, and not dependent on diffusion. On an inoculated agar surface, the antibiotic gradient forms a stable, continuous and exponential gradient of antibiotic concentration. Bacteria grow under the strip, forming an ellipse on the scale, on which you can read the MIC value. Over 90 antimicrobial references are available in the ETEST® range, for easy, effective and precise testing for antibiotics and antifungals, as well as for antimicrobial resistance detection (ARD).



1. Mosley, J.F. et. al. Ceftazidime-Avibactam (Avycaz) For the Treatment of Complicated Intra-Abdominal and Urinary Tract InfectionsPharmacy & Therapeutics. 41(8): 479–483.  2016 Aug.

2. Nicolau, D.P. Focus on ceftazidime-avibactam for optimizing outcomes in complicated intra-abdominal and urinary tract infections. Expert Opin Investig Drugs. 2015;24(9):1261-73.. Epub 2015 Jul 6.

3. Carmeli, Y. Ceftazidime-avibactam or best available therapy in patients with ceftazidime-resistant Enterobacteriaceae and Pseudomonas aeruginosa complicated urinary tract infections or complicated intra-abdominal infections (REPRISE): a randomised, pathogen-directed, phase 3 study. Lancet Infect Dis. 2016 Jun; Epub 2016 Apr 20.

*CE-IVD marked; FDA pending


***Astra Zeneca/Pfizer

ETEST® Ceftazidime/Avibactam (CZA 256)


Single Pack: 30 test strips

Each strip contains:



  • General microbiology laboratory equipment
  • Sterile saline (0.85% NaCl)
  • Rota-plater: Retro C80 (Ref. 559803)
  • Manual applicator or vaccum pen: Mini Grip-It (Ref. 411200), forceps or Nema C88 (Ref. 559804)
  • 0.5 McFarland turbidity standard (Ref. 70 900)
  • Incubator (35 ± 2 °C)
  • Quality control organisms
  • Storage containers with active desiccant capsules (Ref. 501603, 559900, 559901 or 559902), or pouches and/or sealing clamps (Ref. 559809)

Recommended Culture Media

Use well-defined and high-quality Mueller Hinton medium that supports good growth. The brand chosen should have good batch-to-batch reproducibility to ensure that accurate and reliable MIC values are obtained.

To check the quality of media, test appropriate quality control strains. Please refer to the Package Insert provided by the media manufacturer.

Ensure that the agar plate has a depth of 4.0 ± 0.5 mm and pH 7.3 ± 0.1.


  • For in vitro diagnostic use only.
  • For professional use only.
  • Use aseptic procedures at all times when handling bacterial specimens and established precautions against microbiological hazards strictly adhered to.
  • Sterilize agar plates after use, before discarding.
  • The test device is a disposable; it should not be reused.

Please consult your local bioMérieux representative for product availability in your country

Pioneering diagnostics