Figure 4.

A 22-year-old female patient with a history of environmental exposure to ducks. A,B: Axial high-resolution computed tomography scans of the chest showing ground-glass opacities and centrilobular micronodules (arrowheads), in addition to incipient reticular opacities (in A), indicating initial fibrosis, and basal, in some cases lobular, air trapping (arrows in B). C: Papanicolaou-stained bronchoalveolar lavage fluid sample, showing a multinucleated giant cell (arrow), foamy histiocytes (arrowheads), and lymphocytes.