Broth dilution minimum inhibitory concentrations: rationale for use of selected antimicrobial concentrations

A microdilution susceptibility testing procedure utilizing selected, clinically relevant concentrations of a large number of antimicrobial agents is described. A qualitative code designed to facilitate interpretation of quantitative results is coupled with each antimicrobial concentration. Both the antimicrobial concentrations selected for testing and the assigned codes are based on published data regardling attainable antimicrobial levels in serum and urine.