Empirical therapy continues to be effective for some bacterial pathogens because resistance mechanisms have not been observed e.g., continued penicillin
Previous SectionNext SectionĮmergence of Antimicrobial Resistance and the Rationale for Performing Susceptibility TestingThe performance of antimicrobial susceptibility testing by the clinical microbiology laboratory is important to confirm susceptibility to chosen empirical antimicrobial agents, or to detect resistance in individual bacterial isolates. However, newer or emerging mechanisms of resistance require constant vigilance regarding the ability of each test method to accurately detect resistance. In general, current testing methods provide accurate detection of common antimicrobial resistance mechanisms. Some methods provide quantitative results (eg, minimum inhibitory concentration), and all provide qualitative assessments using the categories susceptible, intermediate, or resistant. Each method has strengths and weaknesses, including organisms that may be accurately tested by the method.
Manual methods that provide flexibility and possible cost savings include the disk diffusion and gradient diffusion methods. The most widely used testing methods include broth microdilution or rapid automated instrument methods that use commercially marketed materials and devices. The goals of testing are to detect possible drug resistance in common pathogens and to assure susceptibility to drugs of choice for particular infections. Jorgensen, Dept of Pathology, University of Texas Health Science Center, 7703 Floyd Curl Dr, San Antonio, TX 78229-7750 SectionĪbstractAn important task of the clinical microbiology laboratory is the performance of antimicrobial susceptibility testing of significant bacterial isolates. Mary Jane Ferraro2,3 + Author Affiliationsĭepartment of Pathology, The University of Texas Health Science Center, San Antonio Departments of Pathology, Boston 3Departments of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston1 2ġ. Melvin Weinstein, Section Editor + Author Affiliations 1. Susceptibility Testing: A Review of General Principles and Contemporary Practices1.