Computed tomography of infectious bronchiolitis

(A and B) Axial images from a patient with infectious bronchiolitis. Images show diffuse centrilobular nodules, tree-in-bud pattern, and mild bilateral lower lobe cylindrical bronchiectases. A mosaic pattern of attenuation is seen in both lungs, more conspicuous on the right than on the left. (C) Axial image from a patient with influenza-related bronchiolitis. Bilateral lower lobe predominant centrilobular nodules are seen with a tree-in-bud pattern, mucoid impaction of segmental lower lobe bronchi, and bronchial wall thickening.