Organizing pneumonia histopathology

Photomicrograph shows organizing pneumonia with intraluminal plugs of pale-staining fibroblastic tissue. The configuration of the intraluminal plugs reflects the dichotomously branching architecture of distal airways and alveolar ducts.

Low-power photomicrograph of normal lung tissue shows open alveoli with thin, capillary-containing interstitial spaces. An artery (A) is identifiable by its thick, muscular wall; the accompanying bronchus (B) contains mucoid material and is lined by columnar respiratory epithelial cells.