EUCAST is defining breakpoints in antimicrobial resistance

The European Society of Clinical Microbiology and Infectious Disease (ESCMID) is currently researching the new breakpoints for antimicrobial agents in clinical development through its European Committee on Antimicrobial Susceptibility Testing (EUCAST)

An antimicrobial breakpoint is an agreed concentration to identify at what point the growth of bacterium is inhibited – the minimum inhibitory concentration (MIC) – which essentially defines at what dose each bacteria is considered susceptible or resistant to antimicrobial therapy.  

Breakpoints of new agents are needed to standardise a global definition of resistance and the point at which increased dosages are needed.

Having a common system to determine the defining and measuring of resistance is the ultimate goal of EUCAST and its members according to ESCMID.

Gunnar Kahlmeter, past president and communications officer for ESCMID and the past chairman of EUCAST, said: “There are a great and increasing number of people and groups around the world trying to prevent the development of antimicrobial resistance.

90% of countries are now following the EUCAST categorisation of bacteria as susceptible and resistant to new and existing antimicrobial agents – rising from around 20-30% in 2008.

Jointly funded by ESCMID and the European Centre for Disease Prevention and Control (ECDC), EUCAST has been entrusted by the European Medicines Agency (EMA) for more than 10 years to determine the breakpoints for new antimicrobial agents.

Kahlmeter said: “This work is either aided by the fact that we unite behind one definition of antimicrobial resistance or hampered by our inability to do so.

“Without a harmonised opinion on where to draw the line between which microorganisms can be treated and which can not, we’re unable to efficiently measure the development of resistance and unable to measure the rate at which resistance develops.

“In creating unified values, breakpoints and definitions, it will defer people from inappropriate antibiotic use and encourage the right use of antibiotics along with the right dose when necessary. This is one of the most important tools in defending ourselves against antimicrobial resistance.”