In the Runyon classification, both bacteria are nonchromogens. They can be differentiated from M. tuberculosis and each other by commercially available DNA probes. They are characterized as Gram-positive, nonmotile, acid-fast, short to long rods. Colony characteristics *Usually, colonies are smooth, rarely rough, and not pigmented colonies. Older colonies may become yellow. Physiology *Growth on Löwenstein-Jensen medium and Middlebrook 7H10 agar occurs at 37°C after seven or more days. *The<unk>  can be (but is not often) resistant to isoniazid, ethambutol, rifampin, and streptomycin. Differential characteristics *M. intracellulare and M.<unk>  form the<unk>  <unk> . *Remarkable ITS heterogeneity is seen within different M. intracellulare isolates.
Mycobacterium avium complex
Mycobacterium tuberculosis
Mycobacterium kansasii
Mycoplasma
Mycobacterium haemophilum
Mycobacterium canetti
Mycoplasma pneumonia
Mycobacterium africanum