Non-tuberculous mycobacteria (NTM) are a group of bacteria that are capable of causing opportunistic lung infections and the development of NTM pulmonary disease (NTM-PD). They are distinct from Mycobacterium tuberculosis (TB) and Mycobacterium leprae and are found in the natural environment and water supplies such as taps and shower heads.

Nearly 200 different species of NTM have been identified; Mycobacterium avium complex (MAC) is the commonest to cause infections in the UK. NTM can be inhaled into the lungs via aerosols and pulmonary disease accounts for the majority of infections caused by NTM. For healthy people they rarely cause a problem; however, in immunocompromised patients or those with underlying lung disease they can lead to serious lung infections.

This article outlines how NTM-PD affects the lungs, the investigations required for diagnosis and the treatment for NTM-PD.