In the context of histology, IPF is marked by several key features:
1. Fibroblastic Foci: These are clusters of proliferating fibroblasts and myofibroblasts within the interstitial spaces of the lung. They are indicative of ongoing fibrotic activity. 2. Honeycombing: This refers to the cystic spaces lined by bronchiolar epithelium, typically found in the subpleural and paraseptal regions. These cysts are a result of the destruction of the lung architecture. 3. Interstitial Inflammation: Mild to moderate chronic inflammation can be observed, featuring lymphocytes, plasma cells, and occasional eosinophils. 4. Dense Collagen Deposition: There is significant deposition of dense fibrous connective tissue, leading to the thickening of the alveolar walls.
