Common aetiologies with their clinical features, investigations and specific therapies
| Cause of bronchiectasis | Clinical features | Investigations | Specific treatment |
| Post-infective/tuberculosis | Non-specific | None | None |
| NTM Pulmonary disease | Elderly females, middle lobe nodular bronchiectatic or cavitary disease Weight loss | Sputum culture HRCT appearances may be suggestive | Combination antibiotic treatment for at least 12 months after sputum culture conversion |
| ABPA | Wheezing, mucus production, steroid responsiveness. Central bronchiectasis Staphylococcus aureus infection | Total and specific IgE, eosinophil counts HRCT appearances may be suggestive | Oral corticosteroids Antifungal medication |
| Primary immunodeficiency | Recurrent infections, extrapulmonary infections | Serum immunoglobulins and functional antibodies, e.g. to pneumococcus | Immunoglobulin replacement Prophylactic antibiotics, e.g. macrolides |
| Secondary immunodeficiency | Recurrent infections, extrapulmonary infections, symptoms of the underlying disorder (e.g. haematological malignancy) | Serum immunoglobulins, more detailed immunological investigations | Discontinue immunosuppressive medications Treat underlying disorder Immunoglobulin replacement Prophylactic antibiotics, e.g. macrolides |
| Connective tissue disease | Progressive disease with frequent exacerbations | Clinical history supported by autoantibody measurements | Airway clearance and early introduction of anti-inflammatory treatment with macrolides if frequent exacerbations |
| Inflammatory bowel disease | Sterile bronchorrhoea | Clinical history | Inhaled corticosteroids |
| Alpha-1 antitrypsin deficiency | Basal emphysema Airflow obstruction | Alpha-1 antitrypsin serum level and phenotyping | Smoking cessation Treat airflow obstruction with bronchodilators Supplementation in some countries |
| PCD | Childhood respiratory distress or respiratory symptoms Upper airway symptoms Middle ear infections Cardiac involvement/dextrocardia Early infection with Pseudomonas aeruginosa | Nasal NO High-speed video microscopy Immunofluorescence Electron microscopy Genetics | Airway clearance Genetic counselling Assessment of fertility and cardiac involvement Monitoring and early treatment of P. aeruginosa |
| Cystic fibrosis | Childhood respiratory symptoms Extrapulmonary features Upper airway symptoms Infection with P. aeruginosa or S. aureus | Sweat test Genetics | Airway clearance Multidisciplinary assessment and management within specialist centres Specific therapies not indicated in bronchiectasis, e.g. DNAse CFTR modulators |
| Obstructive | Single lobe involvement | Bronchoscopy | Removal of obstructive lesion if possible |
| Congenital, e.g. tracheobronchomegaly, Williams-Campbell syndrome | Typical radiological appearances Family history | HRCT appearances may be suggestive | None |
| Yellow nail syndrome | Yellow discolouration of fingernails and toenails Lymphoedema Pleural effusions | Clinical features | Treatment of complications, e.g. drainage of pleural effusions |
NTM: nontuberculous mycobacteria; HRCT: high-resolution computed tomography; NO: nitric oxide; CFTR: cystic fibrosis transmembrane conductance regulator.