Best Practices for Management.

For decades, antimicrobial therapy for infection has been given empirically, and the results of therapy (success or failure) have either not been confirmed or when confirmed have not been used to modify prescribing behavior. These practices coupled with increasing antibiotic resistance have resulted in low cure rates overall. Susceptibility testing for has increasingly become available, especially in the United States. Availability of susceptibility-based therapy has encouraged adoption of the principles of antimicrobial stewardship for infection (eg, limiting antibiotic choice to antibiotics for which the infection is susceptible given at optimal doses, formulations, frequency of administration, and duration). Antimicrobial regimens can now be classified as empiric therapies, susceptibility-based therapies, potentially effective therapies requiring optimization, and therapies containing unneeded antibiotics that should not be used. This article describes current best practices and recommendations for integrating culture-based and molecular-based susceptibility testing into therapy.