Mycobacterium immunogenum isolated from a metal worker in Japan

In the United States and European countries, Mycobacterium immunogenum has been identified in metal working 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.immuno genum 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.