From the Guidelines
Interstitial lung disease (ILD) is primarily caused by autoimmune disorders, environmental exposures, and certain medications, with the most significant causes including rheumatoid arthritis, systemic lupus erythematosus, scleroderma, and Sjögren's syndrome, as well as exposures to silica dust, asbestos, and coal dust 1. The causes of ILD can be broadly categorized into several groups, including:
- Autoimmune disorders, such as rheumatoid arthritis, systemic lupus erythematosus, scleroderma, and Sjögren's syndrome, which are frequently associated with lung inflammation 1
- Environmental exposures, including silica dust, asbestos, coal dust, and other occupational irritants that damage lung tissue over time 1
- Medications, particularly chemotherapy drugs like bleomycin, methotrexate, and certain antibiotics such as nitrofurantoin, which can trigger ILD 1
- Genetic factors, with familial pulmonary fibrosis showing inheritance patterns in certain families 1
- Radiation therapy to the chest area, which can cause radiation pneumonitis that may progress to fibrosis 1
- Infections, particularly certain viral and bacterial pneumonias, which can lead to interstitial changes 1 The underlying mechanism of ILD typically involves repeated injury to lung cells, leading to abnormal healing responses, inflammation, and progressive scarring that reduces lung elasticity and impairs oxygen transfer 1. It is essential to note that the causes of ILD can be complex and multifactorial, and a comprehensive approach to diagnosis and management is necessary to improve patient outcomes 1.
From the Research
Causes of Interstitial Lung Disease
The causes of interstitial lung disease (ILD) can be diverse and complex. Some of the known causes include:
- Genetic predispositions 2
- Environmental exposures, such as allergens, toxins, and air pollution 2, 3, 4
- Underlying autoimmune diseases, such as rheumatoid arthritis 5
- Use of certain medications 2
- Occupational exposures, such as inhalation of dust and chemicals 3, 4
Environmental and Occupational Exposures
Environmental and occupational exposures can play a significant role in the development of ILD. These exposures can be directly causal or contribute to the disease in combination with other factors. Examples of such exposures include:
- Smoking 3
- Inhalation of materials in the environment, such as dust and chemicals 3, 4
- Domestic and occupational exposures, such as exposure to mold and birds 4
Autoimmune Diseases
Autoimmune diseases, such as rheumatoid arthritis, can also increase the risk of developing ILD. The usual interstitial pneumonia (UIP) subtype of RA-related ILD shares similar clinical and histopathologic features with idiopathic pulmonary fibrosis, suggesting common mechanistic pathways and potential therapeutic targets 5
Other Factors
Other factors, such as age, sex, and seropositivity for rheumatoid factor and anti-cyclic citrullinated peptide, can also increase the risk of developing ILD 5