American Thoracic Society diagnostic criteria for pulmonary NTM disease*
| Category | Criteria |
|---|---|
| NTM, non-tuberculous mycobacteria. | |
| *A patient must meet clinical, radiographic and microbiological criteria to be classified as having pulmonary NTM disease according to American Thoracic Society guidelines. | |
| Clinical | Compatible signs/symptoms (cough, fatigue, fever, weight loss, haemoptysis, dyspnoea), documented deterioration in clinical status and reasonable exclusion of other disease |
| Radiographic | On chest radiograph, any of: |
| infiltrates (progressive or persistent ⩾2 months) | |
| cavitation | |
| multiple nodules | |
| On high resolution computed tomographic scan, any of: | |
| multiple small nodules | |
| multifocal bronchiectasis | |
| (if baseline films >1 year old, there should be evidence of progression) | |
| Microbiological | With at least three available sputum/bronchial wash samples in 1 year, any of: |
| three positive cultures | |
| two positive cultures with any acid-fast bacilli seen on at least one smear | |
| With only one available bronchial wash and inability to obtain sputum, any of: | |
| positive culture with 2+, 3+ or 4+ growth | |
| positive culture with more than rare acid-fast bacilli seen on smear assessment | |
| With a tissue biopsy: | |
| any growth on bronchopulmonary tissue biopsy | |
| granuloma and/or acid-fast bacilli on lung biopsy with at least 1+ growth from sputum/bronchial wash | |