Common causes of bronchiectasis and chronic rhinosinusitis
| Disorder | Examples | Prevalence of chronic rhinosinusitis | References |
| Idiopathic | 45–84% | 11, 12 | |
| Abnormal mucociliary clearance | PCD | Up to 100% | 13 |
| CF | 14 | ||
| Young’s syndrome | 15 | ||
| Immunocompromise | HIV | Up to100% | 16 |
| Common variable hypogammaglobulinaemia | |||
| Postinfective | Tuberculosis | 50% | 11 |
| Non-tuberculous mycobacteria (eg, MAC) | |||
| Whooping cough | |||
| Measles | |||
| Excessive immune response | ABPA | 40–90% | 17 |
| GvHD | Depends on severity of bronchiectasis | ||
| Inflammatory bowel disease | |||
| Mechanical obstruction | Tumour | Infrequent | |
| Foreign body | |||
| Lymphadenopathy |
ABPA, allergic bronchopulmonary aspergillosis; CF, cystic fibrosis; GvHD, graft versus host disease; HIV, human immunodeficiency virus; MAC, mycobacterium avium complex; PCD, primary ciliary dyskinesia.