Occurrence and antimicrobial susceptibility of Mycobacterium peregrinum in ornamental fish

Systemic mycobacteriosis was diagnosed in a group of ornamental fish. Although a large number of acid-fast bacterial rods were identified in the kidneys, liver, and muscles of each fish, no granulomas were observed in internal organs. Mycobacterium peregrinum was identified using the GenoType Mycobacterium CM assay. This study illustrates a considerable risk of atypical mycobacteriosis in humans.