Temporal heterogeneity of UIP
Temporal heterogeneity of UIP

Asbestosis-related UIP: This low magnification photo demonstrates the temporal heterogeneity of UIP with areas of uninvolved alveolar parenchyma (nl) adjacent to areas of advanced fibrosis (F). Microscopic honeycombing and fibroblast foci were present (not shown). In asbestosis, much of the fibrosis is centered on the small airways. In more advanced disease, bridging to the periphery of lobules occurs producing a UIP pattern. (Hematoxylin and eosin stain, 12.5 x original magnification).