Etiology. Hereditary disease with autosomal dominant type of inheritance.
Pathogenesis. Previously in the development of syndrome there was attached importance of auto-sensitization in connection with which diseases was entered to a group of connective tissue disease. Now there is considered that the syndrome occurs as the result of repeated inflammatory bronchopulmonary diseases. Morphological substrate is perialveolar fibrosis, which reduces the elasticity and pliability of lung tissue and thus worsens the excursion of the lungs. Due to the thickening of the interalveolar septa diffusion of gases in the blood is damaged, which leads to hypoxemia and hypoxia, hypercapnia.
Representative CT scan image from a person with
idiopathic pulmonary fibrosis.
Idiopathic fibrosing alveolitis.
Detail of chest radiograph with interstitial pneumosclerosis with a primary lesion of the alveolar connective tissue (fibrosing alveolitis): small meshy pattern of lung.
Micropreparations of lung at diffuse interstitial pneumosclerosis: interseptums are extremely thickened and sclerotic; coloured by Van Gieson; × 24.
A. Lung showing extensive interstitial and alveolar fibrosis.
Note the increased interstitial cellularity with numerous fibroblasts.
B. Patchy areas of alveolar septal thickening and prominent hyaline membranes.
C. Higher magnification showing typical dense laminated hyaline membranes.
D. Alveolar septum showing prominent type II pneumocyte proliferation.
E. Abundant polymorphonuclear leukocytes fill alveolar spaces with focal destruction of alveolar septa.
F. Higher power magnification showing the antraalveolar exudate
composed mainly of polymorphonuclear leukocytes, red blood cells, and fibrin.
Original magnifications: A & B, x 50; C, x 100; D, x 158; E, x 50; F, x 158.
Electron-microscopic picture of fibrosed alveoli.
CT-image of meshy lung
Vacuolization of macrophages in amiodarone alveolitis. Materials obtained through bronchoalveolar lavage.
Diagnostic criteria of IFA
Treatment.Prognosis is unfavorable.