tree-in-bud appearance

tree-in-bud appearance

A fanciful term for HRCT (thin-slice CT) changes in the lung, consisting of centrilobular opacities/nodules that correspond to luminal impaction of bronchioles focally dilated with mucus, pus or fluid, and accompanied by bronchial wall thickening and peribronchiolar inflammation, highlighting the normally invisible branching course of the peripheral airways.

Tree-in-bud appearance
(1) Endobronchial spread of infection (Mycobacterium tuberculosis, M avium-intercellulare, M kansasii, human T-lymphotropic virus type 1, Mycoplasma pneumoniae or any bacterial bronchopneumonia);
(2) Airway disease associated with infection (cystic fibrosis, bronchiectasis); or
(3) Airway disease associated primarily with mucus retention (allergic bronchopulmonary aspergillosis, asthma, diffuse panbronchiolitis and diffuse aspiration bronchiolitis).