The Problem of Selecting Antimicrobial Agents Before (or Without) the Results of Susceptibility Testing

Abstract

A recent article in this section reviewed some problem areas of susceptibility testing. In particular, the “myth” of susceptibility testing being predictive of clinical outcome was discussed. The realization of this myth often leaves clinicians less comfortable when selecting antimicrobial agents. The question they often ask is, “How does one select antibiotics?” This question has always been important for empiric therapy of the septic patient. It has become even more important in the cost containment era. The introduction of new antimicrobial agents that are very costly when compared with older agents has greatly complicated antimicrobial therapy. It is now possible to use antibiotics correctly in a therapeutic sense, but to misuse them in an economic sense. Nonetheless, recognition of new pathogens, increasing resistance of pathogens to older antimicrobial agents and more complicated clinical problems have increased the need for these new agents. The following discussion will focus on those factors upon which the selection of a specific antimicrobial agent (or combination of agents) is based, the least of which should be the results of susceptibility tests.