Breakpoints to determine whether clinical isolates of M. avium or M. intracellulare are susceptible or resistant to azithromycin have not been established.The clinical relevance of azithromycin in vitro susceptibility test results for other mycobacterial species, including Mycobacterium tuberculosis, using any susceptibility testing method has not been determined.13 NONCLINICAL TOXICOLOGY13.1 Carc