An official ATS/IDSA statement: Diagnosis, treatment, and prevention of nontuberculous mycobacterial diseases

The minimum evaluation of a patient suspected of nontuberculous mycobacterial (NTM) lung disease should include the following: (I) chest radiograph or, in the absence of cavitation, chest high-resolution computed tomography (HRCT) scan; (2) three or more sputum specimens for acid-fast bacilli (AFB) analysis; and (3) exclusion of other disorders, such as tuberculosis (TB). Clinical, radiographic, and microbiologic criteria are equally important and all must be met to make a diagnosis of NTM lung disease. The following criteria apply to symptomatic patients with radiographic opacities, nodular or cavitary, or an HRCT scan that shows multifocal bronchiectasis with multiple small nodules. These criteria fit best with Mycobacterium avium complex (MAC), M. kansasii, and M. abscessus. There is not enough known about most other NTM to be certain that these diagnostic criteria are universally applicable for all NTM respiratory pathogens.