Clinical and microbiological criteria for diagnosis of nontuberculous mycobacterial lung diseasea

Criterion typeDescription
Clinical(i) Pulmonary symptoms, nodular or cavitary opacities on chest radiograph, or a high-resolution computed tomography scan that shows multifocal bronchiectasis with multiple small nodules and (ii) appropriate exclusion of other diagnoses
Microbiological(i) Positive culture results from at least 2 separate expectorated sputum samples, and if the results from 2 sputum samples are nondiagnostic (i.e., culture negative), consider repeat sputum AFB smears and cultures; (ii) positive culture result from at least 1 bronchial wash or lavage specimen; or (iii) transbronchial or other lung biopsy specimen with mycobacterial histopathological features (granulomatous inflammation or AFB) and positive culture for NTM or biopsy specimen showing mycobacterial histopathological features (granulomatous inflammation or AFB) and 1 or more sputum or bronchial wash specimens that are culture positive for NTM
Patient management(i) Expert consultation should be obtained when NTM that either are infrequently encountered or usually represent environmental contamination are recovered; (ii) patients who are suspected of having NTM lung disease but do not meet the diagnostic criteria should be monitored until the diagnosis is firmly established or excluded; and (iii) making the diagnosis of NTM lung disease does not, per se, necessitate the institution of therapy, which is a decision based on potential risks and benefits of therapy for individual patients
  • a Adapted from reference 52 with permission of the American Thoracic Society (copyright © 2007 American Thoracic Society).