What are the causes of Interstitial lung disease (ILD)?
Interstitial lung disease includes a group of diseases that have to thicken of the supporting tissues between the air sacs of the lungs as the common factor. The interstitium is a thin layer of tissue that is normally appears as a fine lace on X-rays or imaging studies (best visualized as the appearance of a sponge). Interstitial lung disease results from a variety of causes that lead to thickening of the supporting tissue around the air sacs rather than the air sacs themselves. Interstitial lung disease usually involves all of the lungs diffusely rather than affecting only one area.
Interstitial lung disease includes a group of diseases that have thickening of the supporting tissues between the air sacs of the lungs. This thickening can be due to a variety of causes such as
1 Associated autoimmune or collagen vascular diseases.
2. Exposure to medications or toxins such as asbestos, tobacco smoke, or environmental toxins.
3. Associated genetic diseases.
4. The cause is not known (idiopathic).
The most common symptom of all forms of interstitial lung disease is shortness of breath. Nearly all people with interstitial lung disease will experience breathlessness, which may get worse over time.
Other symptoms of interstitial lung disease include:
- Cough, which is usually dry and nonproductive.
- Weight loss
The diagnosis of interstitial lung disease typically involves imaging tests (Chest X-ray, Computed tomography (CT scan), High-resolution CT scan, Pulmonary function testing measurement of blood oxygen levels, and sometimes, biopsies or tissue sampling.
Interstitial lung disease has a broad list of causes. The exact cause of interstitial lung disease is not always known (idiopathic). Some of the known common causes include toxins, environmental factors, chronic diseases, cancer, and infections. Depending on the cause, interstitial lung disease can resolve or may lead to irreversible scarring and damage to the lungs.
Known causes of interstitial lung disease include the following:
- Environmental factors, such as toxins like asbestos, mold, certain metals, silica dust, talc, grain dust, or bird droppings; interstitial disease caused by some of these irritants is referred to as “hypersensitivity pneumonitis”
- Radiation therapy to the chest
- Certain medications, including some chemotherapy (cancer-fighting) medications and the heart medication amiodarone (Cordarone)
- Chronic autoimmune diseases like rheumatoid arthritis, scleroderma, and lupus
- Infections: One of the more common infectious cause of interstitial inflammation is the bacterium Mycoplasma pneumoniae. Viruses, bacteria, and fungi can all cause interstitial inflammation.
- Cancer in some cases spreads throughout the lymph system in the lungs and appears as interstitial disease
- Congestive heart failure, renal failure both can present with similar findings due to excess fluid in the spongy tissue of the lung
Examples of idiopathic (unknown causes) forms of interstitial lung disease include:
- Bronchiolitis obliterans with organizing pneumonia (BOOP), sometimes known as cryptogenic organizing pneumonia (COP)
- Usual interstitial pneumonitis (UIP)
- Lymphocytic interstitial pneumonitis (LIP)
- Desquamative interstitial pneumonitis (DIP)
- Langerhans cell histiocytosis
The distinction among these idiopathic conditions is based on the exact pattern of lung damage, severity, and location of the disease.
The treatment of interstitial lung disease depends upon the cause. Definitive diagnosis is often essential since the treatment may involve:
- antimicrobial agents,
- immunosuppressing agents,
- Avoidance behaviour,
- chemotherapy, and
- in some, no therapy is available.
Depending upon the severity of the symptoms, respiratory support, including supplemental oxygen and even ventilator support, may be required. Respiratory therapists may be part of a treatment team with the goal of improving day to day function. Smoking cessation is an essential part of the treatment for anyone with interstitial lung disease.
Stem Cell Treatment has been known to restore respiratory functions and improve Interstitial lung disease (ILD). Response to treatments varies extensively. Some forms of ILD may improve quickly with Stem Cell Treatment, while others may not respond at all. Treatment is regarded successful if it stabilizes the symptoms as well as the physiological and x-ray findings.
Interstitial lung disease can be prevented only to the extent that its individual causes may be prevented. For example, avoidance of known environmental toxins can help prevent lung damage from these exposures.
The lung is a complex organ with limited regenerative capacity and lung injuries are leading causes of morbidity and mortality worldwide. It is believed that stem cells act through the paracrine mechanism. Regeneration of tissue by stem cells from autologous or allogenic sources can be alternative choice for ILD, not responding to conventional therapy. Different studies are conducted to support that bone marrow progenitor cells contribute to repair and remodelling of lung in animal models of progressive pulmonary fibrosis. Recent studies have demonstrated paracrine effects of administered cells, including stimulation of angiogenesis and modulation of local inflammatory and immune responses in model mouse lung disease. Also, some recent studies demonstrate that mesenchymal stem cells (MSCs) can modulate local inflammatory and immune responses in mouse lung disease models. Mesenchymal stem cells are known to home to site of cell injury, inhibit inflammation and hasten cell repair.