UNE-EN ISO 20776-1:2021

This part of ISO 20776 describes one reference method, broth micro-dilution, for determination of MICs.

The MIC may be a guide for the clinician, and reflects the activity of the drug under the described test

conditions, by taking into account other factors, such as drug pharmacology, pharmacokinetics, or

bacterial resistance mechanisms. This allows categorisation of bacteria as susceptible (S),

intermediate (I), or resistant (R). In addition, MIC distributions can be used to define wild type or non119

wild type bacterial populations. Although clinical interpretation of the MIC value is beyond the scope of

this part of ISO 20776, modifications of the basic method are required for certain antimicrobial agent -

bacteria combinations to facilitate clinical interpretation. These modifications are included in a separate

Annex of this document. It is necessary to compare other susceptibility testing methods (e.g. disc diffusion

or diagnostic test devices) with this reference method for validation, in order to ensure comparable and

reliable results.