Decide whether the disease is ACTIVE (cavitation, tree-in-bud, consolidation, new nodules) or sequelae (fibrosis, calcified granuloma, bronchiectasis), because that is the question the physician is asking.
Orient first
- Primary tuberculosis (children, immunocompromised) shows lymphadenopathy, consolidation in any lobe and pleural effusion; post-primary (reactivation) favours the apical and posterior upper lobe segments and the superior lower-lobe segments.
- Activity is shown by cavitation, tree-in-bud centrilobular nodules (endobronchial spread), consolidation and miliary nodules — calcification and fibrotic volume loss are signs of old disease.
- Imaging cannot prove or exclude activity on its own; sputum microbiology decides. The report says "features favouring active disease" or "likely sequelae", not "healed".
Acquire the study
- PA erect radiograph; apical lordotic view is rarely needed now that CT is available.
The manoeuvre
- Upper zones and apices first: patchy consolidation, cavitation (air inside an opacity), and volume loss with hilar elevation.
- Miliary pattern: innumerable 1–3 mm nodules evenly distributed — compare with the lung bases on a well-penetrated radiograph.
- Hila and paratracheal stripe: lymphadenopathy (primary disease, children, HIV).
- Pleura: effusion (often unilateral), pleural thickening or calcification from old disease.
- Compare with any previous radiograph — change over time is the strongest radiographic clue to activity.
What confirms it
- Cavitation or tree-in-bud nodules in a typical distribution, supporting — not proving — active disease.
What licenses you to exclude it
- A normal radiograph lowers the likelihood of active pulmonary tuberculosis but does not exclude it, especially in HIV or early miliary disease.
The classic misread
- Calling apical fibrosis and calcified nodules "active tuberculosis" without a previous film for comparison.