| Infections |
| Bacterial |
| Pneumocystis jiroveci |
| Viral pneumonia |
| Vasculitis |
| Diffuse alveolar haemorrhage |
| Non-specific interstitial pneumonia |
| Desquamative interstitial pneumonia |
| Organising pneumonia |
| Eosinophilic pneumonia |
| Pulmonary alveolar proteinosis |
| Pulmonary oedema |