Susceptibility Test Methods: Mycobacteria, Nocardia , and Other Actinomycetes

This chapter has four major sections. First is a brief review of antimicrobial agents used to treat mycobacterial infections. This is followed by a discussion of methods used to test susceptibility of Mycobacterium tuberculosis complex to first- and second-line agents. Methods described are agar proportion, rapid broth systems, broth microdilution, and molecular techniques, which are being used with increasing frequency. The next topic is susceptibility testing of nontuberculous mycobacteria by broth microdilution, focusing on Mycobacterium avium complex, Mycobacterium kansasii, Mycobacterium marinum, and the rapidly growing mycobacteria. The last section covers susceptibility testing of Nocardia species by broth microdilution and includes a brief discussion of other aerobic actinomycetes.