ABSTRACT
The agar dilution susceptibility-testing method is utilized for the determination of the minimal inhibitory concentration (MIC) of an antimicrobial agent required to inhibit the growth of a microorganism. As with broth dilution susceptibility tests, the agar dilution method provides a quantitative result in the form of an MIC, in contrast to disk diffusion susceptibility tests that result in an indirect measure of susceptibility and provide a qualitative interpretative result. The agar dilution method is the most well-established method for determining antimicrobial susceptibility and is commonly used as the standard or reference method for evaluation of new antimicrobial agents and susceptibility test methods [1-10]. In addition, it offers the convenience of simultaneously testing a number of isolates (32-36), being able to detect mixed cultures or heterogeneous populations, and flexibility in antibiotic selection and concentration range to be tested.
