Fig. 2

Illustrations of radiological patterns caused by intrathoracic TB in children. Panel a. Primary Ghon focus with uncomplicated lymph node disease. Hilar and mediastinal lymphadenopathy associated with an ipsilateral peripheral nodule, or “Ghon focus” (right lung); these nodules are often subpleural with an overlying pleural reaction. Panel b. Progressive Ghon focus with uncomplicated lymph node disease. A Ghon focus with cavitation (right lung), which is seen almost exclusively in infants and immunocompromised children; other elements of the Ghon complex are also visible. Panel c. Complicated lymph node disease with bronchial compression. Enlarged lymph nodes compressing the airway, causing either complete obstruction with lobar collapse (right middle and lower lobes), or partial obstruction with a ball-valve effect leading to hyperinflation (left upper and lower lobes). Panel d. Complicated lymph node disease with bronchopneumonia. Necrotic lymph nodes erupting into bronchus intermedius, with endobronchial spread and patchy consolidation of the middle lobe (right lung). Panel e. Complicated lymph node disease with expansile lobar pneumonia. Necrotic lymph nodes that compress and obstruct the left upper lobe bronchus and may infiltrate a phrenic nerve, causing hemidiaphragmatic palsy (left-sided); endobronchial spread causes dense consolidation of the entire lobe (left upper lobe), with displacement of the trachea and fissures and the formation of focal cavities. Panel f. Miliary (disseminated) disease. Diffuse micronodules in both lungs, which may result from lymphohematogenous spread after recent primary infection or from infiltrating a necrotic lymph node or lung lesion into a blood vessel, leading to hematogenous spread