Primary isolation of Mycobacterium chelonei subspecies abscessus from pus inoculated into peptone broth.

We have described the isolation of Mycobacterium chelonei subspecies abscessus which on two occasions grew out within 4 days in routine cultures after inoculation with purulent material from injection abscesses in a patient with diabetes mellitus. Media isolation and culture characteristics of this organism in comparison to others in the Mycobacterium fortuitum complex are described. Mycobacteria in routine laboratory media can be mistaken for diphtheroids or other "contaminants" or can be overlooked entirely. The possibility of clinical infection of mycobacterial species should be kept in mind when confronted with "sterile" abscesses at injection sites.