Antimicrobial Susceptibility Testing of Anaerobic Bacteria: A Mini-Review

Obligate anaerobic bacteria have pivotal roles in the microbiota of humans and they are significant
infectious agents involved in many pathological processes, both in immunocompetent and
immunocompromised individuals. Their isolation, cultivation and correct identification differs
significantly from the workup of aerobic species, although the use of new technologies (e.g., matrixassisted
laser desorption/ionization time-of-flight mass spectrometry, whole genome sequencing)
changed anaerobic diagnostics dramatically. For these reasons, antimicrobial susceptibility testing of
anaerobic isolates for surveillance purposes or otherwise is of paramount importance but the
availability of these testing methods is usually limited. In this chapter, our aim was to give an overview
of the methods currently available for the antimicrobial susceptibility testing (agar dilution, broth
microdilution, disk diffusion, gradient tests, automated systems, phenotypic and molecular resistance
detection techniques) of anaerobes, when should these methods be used and what are the recent
developments in resistance patterns of anaerobic bacteria.