New EUCAST criteria and breakpoints, implication for daily practice
(Nuevos criterios y puntos de corte de EUCAST, implicaciones en la práctica clínica diaria)“,
Dr. Rafael Cantón
Servicio de Microbiología. Hospital Universitario Ramón y Cajal. Madrid. Spain.
rafael.canton@salud.madrid.org
The European Committee of Antimicrobial Susceptibility Testing (EUCAST) has recently introduced two relevant modifications in the criteria used to interpret antimicrobial susceptibility testing values. The first one is related to the “intermediate” clinical category when using clinical breakpoints. Now it is referred to category “I” = susceptible increased exposure, avoiding uncertainty in the interpretation of this category. This change improves the use of antimicrobials by adapting doses when the MIC is categorised as “I”. The second modification is the breakpoints in brackets, now for aminoglycosides and their systemic use. They are based on epidemiological cut-off values (ECOFFs) that distinguish between organisms with and without acquired resistance mechanisms. They do not predict clinical susceptibility but in some situations and/or when the agent is combined with another active agent, therapy may be considered. These modifications are included in the EUCAST breakpoint tables thr are annually updated (www.eucast.org)