Antimicrobial susceptibility tests and their role in therapeutic drug monitoring.

Principles and techniques of routine and special in vitro antimicrobial susceptibility testing of bacteria are reviewed with emphasis on the advantages, limitations, and potential problems of each method. The utilities of MBC testing and of serum bactericidal titer determination are discussed in the clinical context. The use of testing for possible antibiotic interactions is examined in light of potential benefits and risks of combination antimicrobial therapy.