Table 1.
HRCT patterns and differential diagnosis of interstitial lung diseases
| HRCT PATTERN | DIFFERENTIAL DIAGNOSIS OF DISEASES | ||
|---|---|---|---|
| Septal | Hydrostatic pulmonary oedema, lymphangitic carcinomatosis, sarcoidosis, Niemann-Pick disease, Erdheim-Chester disease, cystic lymphangiectasia, pulmonary lymphangiomatosis | ||
| Reticular | IPF, NSIP, asbestosis, chronic HP, rheumatoid arthritis, DIP, end-stage sarcoidosis | ||
| GGO | Subacute HP, RBILD, DIP, Pneumocystis pneumonia | ||
| Crazy paving pattern | Alveolar proteinosis, Pneumocystis pneumonia, exogenous lipoid pneumonia, sarcoidosis, diffuse alveolar haemorrhage, viral/opportunistic infection, invasive mucinous adenocarcinoma | ||
| Mixed GGO and reticular | NSIP, scleroderma, IPF, DIP | ||
| Nodular | Random | Haematogenous metastases, miliary infection | |
| Perilymphatic | Sarcoidosis, silicosis, coal workers pneumoconiosis | ||
| Centrilobular | without tree-in-bud | silicosis, coal workers pneumoconiosis | |
| with tree-in-bud | Panbronchiolitis, tuberculosis, atypical mycobecteria infection, metastatic tumour emboli | ||
| ill-defined | Subacute HP, RBILD, cryptogenic organising pneumonia, lymphocytic interstitial pneumonia, follicular bronchiolitis | ||
| Reticulonodular | Sarcoidosis, berylliosis, lymphangitic carcinomatosis | ||
| Cystic | Lymphangioleiomyomatosis, pulmonary histiocytosis, lymphocytic interstitial pneumonia, centrilobular emphysema | ||
| Mixed Cystic and GGO | Pneumocystis pneumonia, lymphocytic interstitial pneumonia, subacute HP, DIP | ||
| Decreased attenuation | Obliterative bronchiolitis, panlobular emphysema | ||
| Mosaic attenuation | Obliterative bronchiolitis, chronic thromboembolic pulmonary hypertension, subacute HP, RBILD | ||
DIP desquamative interstitial pneumonia, GGO ground-glass opacity, HP hypersensitivity pneumonitis, IPF idiopathic pulmonary fibrosis, NSIP non-specific interstitial pneumonia, RBILD respiratory bronchiolitis–associated with interstitial lung disease