Antimicrobial susceptibility testing breakpoints and methods from BSAC to EUCAST

Area of Science:

• Microbiology
• Clinical Pharmacology
• Infectious Diseases

Background:

• European national committees, including the BSAC, initiated harmonization of antimicrobial susceptibility testing (AST) clinical MIC breakpoints in 2002.
• The European Committee on Antimicrobial Susceptibility Testing (EUCAST) has since established breakpoints for new antimicrobial agents following EMA guidelines.
• EUCAST breakpoints are now widely adopted by European laboratories.

Purpose of the Study:

• To describe the harmonization of clinical MIC breakpoints for antimicrobial susceptibility testing in Europe.
• To highlight the adoption and implementation of EUCAST breakpoints by national committees and laboratories.
• To emphasize the benefits of harmonized breakpoints for international surveillance and reporting.

Main Methods:

• Harmonization of clinical MIC breakpoints for commonly used and new antimicrobial agents.
• Adoption and implementation of EUCAST breakpoints by the BSAC into its disc diffusion susceptibility testing method.
• Transition from national disc diffusion methods to the standardized EUCAST disc diffusion method.

Main Results:

• Harmonization of breakpoints is complete for common agents and ongoing for new agents.
• The BSAC has implemented EUCAST breakpoints and will phase out support for its own disc diffusion method by January 2016.
• EUCAST breakpoints are accessible through automated systems, facilitating widespread use.

Conclusions:

• Harmonized antimicrobial susceptibility testing breakpoints and methods prevent discrepancies in susceptibility reporting across different countries.
• Standardization enhances the reliability of antimicrobial resistance rate comparisons in international surveillance studies.
• The adoption of EUCAST breakpoints promotes consistent patient management and public health strategies regarding antimicrobial resistance.