Antimicrobial Susceptibility Testing: An Updated Primer and Clinical Implications for Pediatricians

Deniz GÜRa

aHacettepe University Faculty of Medicine, Department of Medical Microbiology, Retired Faculty Member, Ankara, Türkiye

ABSTRACT

Antimicrobial susceptibility tests (AST) guide the clinicians for choosing the optimal therapy. There are many conventional phenotypic methods that can be used routinely to determine antibiotic susceptibility and among these, the ”microbroth dilution test” is considered the gold standard. Quantitative tests which give minimum inhibitory concentration (MIC) of the antibiotic should be preferred in serious infections. Antibiotic susceptibility test results do not always guarantee success in therapy and results should always be analyzed with pharmacokinetic (PK) parameters. Conventional phenotypic antibiotic susceptibility test procedures and interpretation of test results will be summarized in this review.

Keywords: Microbial sensitivity tests; minimum inhibitory concentration; disk diffusion antimicrobial tests; serum bactericidal test; etest

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