Opportunistic bacterial infection Nontuberculous mycobacterial pulmonary infection 2019-01-27T18:38:45Z An infection of the lung caused by environmental mycobacteria. Such infections can occur in individuals with predisposing lung disease or immune disease. Historically, human infections due to Mycobacterium were due almost exclusively to Mycobacterium tuberculosis (TB); the extensive societal impact of this infection is legendary. More recently, other species of mycobacterium causing clinical disease have been identified and, in many geographical regions, cause greater disease burden than TB. These organisms are referred to by a variety of collective names such as anonymous or atypical mycobacteria, mycobacteria other than tuberculosis (MOTT) and nontuberculous mycobacteria (NTM).