Intraluminal fibrosis in interstitial lung disorders. Academic Article uri icon

Overview

MeSH

  • Alveolitis, Extrinsic Allergic
  • Connective Tissue
  • Exudates and Transudates
  • Humans
  • Microscopy, Electron
  • Pulmonary Alveoli
  • Time Factors

MeSH Major

  • Lung Diseases
  • Pulmonary Fibrosis

abstract

  • The histopathologic and ultrastructural features of intraluminal organizing and fibrotic changes were studied in open lung biopsies and autopsy specimens from 373 patients with interstitial lung disorders, including hypersensitivity pneumonitis (n = 44), idiopathic pulmonary fibrosis (n = 92), collagen-vascular diseases (n = 20), chronic eosinophilic pneumonia (n = 10), pulmonary histiocytosis X (n-90), pulmonary sarcoidosis (n = 62), pneumoconioses (n = 25), Legionnaire's disease (n = 5), drug- and toxin-induced pneumonitis (n = 4), radiation-induced pneumonitis (n = 2), lymphangioleiomyomatosis (n = 11), and chronic organizing pneumonia of unknown cause (n = 8). Three patterns of intraluminal organization and fibrosis were recognized: 1) intraluminal buds, which partially filled the alveoli, alveolar ducts and/or distal bronchioles; 2) obliterative changes, in which loose connective tissue masses obliterated the lumens of alveoli, alveolar ducts or distal bronchioles, and 3) mural incorporation of previously intraluminal connective tissue masses, which fused with alveolar, alveolar ductal, or bronchiolar structures and frequently became reepithelialized. All three patterns had common morphologic features, suggesting that, regardless of their severity, they resulted from a common pathogenetic mechanism, ie, the migration of activated connective tissue cells, through defects in the epithelial lining and its basement membrane, from the interstitial into the intraluminal compartment. Intraluminal buds were observed most frequently in hypersensitivity pneumonitis, chronic eosinophilic pneumonia, and organizing pneumonia of unknown cause. Mural incorporation and, to a lesser extent, obliterative changes were observed in most interstitial disorders and were very prominent in idiopathic pulmonary fibrosis. Mural incorporation and obliterative changes play an important role in pulmonary remodeling, especially when several adjacent alveoli and/or other air spaces are involved. Under these circumstances, intraluminal organization can mediate the fusion of adjacent alveolar structures by intraluminal connective tissue.

publication date

  • March 1986

has subject area

  • Alveolitis, Extrinsic Allergic
  • Connective Tissue
  • Exudates and Transudates
  • Humans
  • Lung Diseases
  • Microscopy, Electron
  • Pulmonary Alveoli
  • Pulmonary Fibrosis
  • Time Factors

Research

keywords

  • Journal Article

Identity

Language

  • eng

PubMed Central ID

  • PMC1888228

PubMed ID

  • 3953768

Additional Document Info

start page

  • 443

end page

  • 461

volume

  • 122

number

  • 3