Mycobacterium chelonei.

Mycobacterium chelonei is the more important of the two rapidly growing pathogenic mycobacteria; the other being M. fortuitum with which the former has frequently been confused. There are two major variants: M. chelonei chelonei, found mainly in Europe and M. chelonei abscessus, the predominant type in Africa and America. These variants are easily distinguished from M. fortuitum and all other rapidly growing mycobacteria. The species has had a confusing taxonomic history and contains entities known as M. abscessus, M. borstelense, M. friedmannii, M. runyonii and M. salmoniphilum.