Quick Review Cards for Medical Laboratory Science

Classification of Nontuberculous

Mycobacteria Based on Physiology

Clinical Microbiology Review 211

RUNYOUN GROUP CHARACTERISTICS EXAMPLES

Photochromogens

Scotochromogens

Nonphotochromogens

Rapid growers

M. marinum, M. kansasii

M. gordonae

M. avium complex, M. ulcerans

M. smegmatis

Yellow pigment when exposed to light after being grown in dark.

>7 days to appear on solid media.

Yellow pigment when grown in light or dark.

>7 days to appear on solid media.

No pigment produced in light or dark.

>7 days to appear on solid media.

<7 days to appear on solid media.