Pulmonology Quicklinks
ILD PATHOGENESIS
The development of ILD can be of an unknown cause (idiopathic) or due to known underlying condition.1 Among subgroups of idiopathic ILD including desquamative interstitial pneumonia (DIP), lymphoid interstitial pneumonia (LIP), and others, the most common subgroup of idiopathic ILD is idiopathic pulmonary fibrosis (IPF). While secondary ILD can be associated with underlying autoimmune diseases, pneumotoxic drugs, or organic and/or inorganic inhaled substances.1
Although the exact pathogenesis of idiopathic pulmonary fibrosis and the mechanism of initiating and maintaining fibrosis are unknown, it is believed to involve formation of fibroblastic foci, which is a foci of proliferating fibroblasts of pathologic repair mechanism following injury to the alveolar epithelial cells.2,3
The pathologic fibrotic repair pathway, under the presence of transforming growth factor beta (TGF-β), results in the differentiation of fibroblasts into myofibroblasts. Myofibroblasts then secrete collagen and other extracellular matrix proteins at the injury sites, leading to fibrosis.3
Resources
REFERENCES
- Bourke SJ. Interstitial lung disease: progress and problems. Postgrad Med J. 2006;82(970):494-499. doi:10.1136/pgmj.2006.046417.
- Harari S, Caminati A. IPF: new insight on pathogenesis and treatment. Allergy. 2010;65(5):537-553. doi:10.1111/j.1398-9995.2009.02305.x.
- du Bois RM. Fibroblastic foci: time to be counted?. Chest. 2006;130(1):3-5. doi:10.1378/chest.130.1.3.
