[Mycobacterium immunogenum isolated from a metal worker in Japan]

In the United States and European countries, Mycobacterium immunogenum has been identified in metalworking fluids and is reported to be a causative agent of metalworking fluid-associated hypersensitivity pneumonitis. However, in Japan, there has been no reports of M. immunogenum isolated from metalworking fluids. This is the first report of isolation of the microorganism from the sputum of a metal-grinding machine worker in Japan. We should consider the possibility of M. immunogenum infection in case of non-tuberculosis mycobacteriosis and hypersensitivity pneumonitis in metalworkers.