Breakpoints in brackets in EUCAST tables

Recently, EUCAST introduced the concept of “breakpoints in brackets” to warn against the use of specific agents without the use of additional therapeutic measures. For these agents, clinical evidence as monotherapy is usually lacking, but they may still be used for a specific indication or in combination with another active agent or measure.

Breakpoints in brackets are in essence ECOFFs that distinguish between isolates with and without acquired resistance. Because they sometimes serve more than a single species, they may represent a “best fit” ECOFF. When in doubt as to the validity of the bracketed breakpoint, go to www.mic.eucast.org to find the precise ECOFF for a specific species.