Interstitial lung disease or Diffuse Parenchymal lung disease is a large group of disorders that affects the interstitium (the tissue that surrounds and separates the air sac). It causes inflammation and progressive lung tissue scarring or Pulmonary Fibrosis.
Other parts of the lungs may also be affected, including: alveoli, trachea, bronchi, bronchioles, blood vessels and pleura. This kind of damage in the lungs is generally permanent and irreversible. As a result, it affects a person’s ability to breathe and lowers the amount of oxygen in the bloodstream.
ILD is a rare disease, but nowadays it has become more common. In the United States, a study reported that 80.9 per 100.000 men and 67.2 per 100,000 women suffer from interstitial lung disease. It is most common among adults between the ages of 40 and 70, but it also occurs in children (Childhood Interstitial Disease).
Studies have found that ILD had spread throughout the world, in many different racial and ethnic groups. People with autoimmune disease like lupus, rheumatoid arthritis and scleroderma are more often seen to have interstitial lung disease.
Interstitial Pneumonia – caused by bacteria, fungi or viruses that infect the interstitium. The most common agent is mycoplasma pneumonia.
- Idiopathic Pulmonary Fibrosis- is severe, progressive scarring of the interstitium. The cause is unknown.
- Nonspecific interstitial pneumonitis- common to patients with autoimmune disease.
- Cryptogenic organizing pneumonia (COP)- ILD with pneumonia-like symptoms, but without presence of infection.
- Hypersensitivity pneumonitis- caused by exposure to different type of irritants, dust or molds.
- Acute interstitial pneumonitis- chronic but sudden type of ILD.
- Desquamative interstitial pneumonitis- most common among smokers and those with a history of smoking.
- Sarcoidosis- inflammation affects organs of the body. Usually the lymph nodes and the lungs. Granuloma (abnormal masses) alters the function of the affected organs.
- Asbetosis- caused by inhalation of asbestos.
Interstitial Lung Disease is caused by number of factors, including:
Environmental toxins and pollutants
Long term exposure to substances such as asbestos, silica dust, grain dust, gases, fumes, tobacco smoke, bird and animal droppings cannot be easily eliminated from the body and causes direct injury to the lungs.
Cancer patients undergoing long-term radiation therapy show symptoms of lung damage some years after the start of treatment.
Autoimmune disorders like Systemic lupus erythematosus, Rheumatoid arthritis, Sarcoidosis and Scleroderma.
Some medicines are known to damage the lungs. Some drugs used for chemotherapy, heart diseases and antibiotics can also cause it.
Rare, about 8% of people suffering ILD get it genetically.
Idiopathic or unknown cause
Has been also associated with the disease development.
Interstitial Lung Disease involves inflammation and scarring of interstitial tissue. Tissues become thick and as a result, lungs can no longer function well.
Interstitial Lung Disease- Acute
Primary Symptoms includes:
- Shortness of breathing, is a result of reduced breathing capacity
- Non productive cough
- Crackles (abnormal chest sound)
- Cyanosis- this is a result of decreased oxygen levels in the blood, and may result in a bluish discoloration of the skin.
Interstitial Lung Disease- Chronic
In most cases, these symptoms become chronic. Signs are:
- Clubbing of the fingers
- Enlargement of the heart.
In some cases these symptoms are also involved:
- Weight loss
- Muscle pain
- Joint pain
In most cases, a number of diagnostic tests are used, since medical history and physical examination are not enough to confirm the disease. They are tools used by doctors to rule out interstitial lung disease. The following tests are necessary:
Most of the time a chest x-ray is used as the first diagnostic step, and also used to detect the progression of disease.
Computerized Tomography (CT)
Images are taken from different angles to visualize cross sectional images of the lungs, including their internal structure. A CT scan determines the severity of lung damage. It also distinguishes if fibrosis or active inflammation has already taken place.
It measures the oxygen level of the blood.
Is done to visualize the heart’s structure and to show heart function. It is also used to determine if the disease has affected the heart.
Is to test pulmonary function. It measures the amount of air your lungs can hold, and the airflow in and out of the lungs.
This procedure is non-invasive. The doctor will introduce a solution into an area of your lung and create suction. The collected output contains cells from the air sacs. It identifies the causes of interstitial lung diseases (infection, auto immune).
Is a procedure where lung tissue samples are removed and sent to laboratory to be examined by a pathologist. For accurate diagnosis, large amounts of lung tissue are collected.
Treatment for Interstital Lung Disease depends on what causes the disease and the overall health status of the patient. The scarring of interstitial tissues (Pulmonary Fibrosis) is irreversible, and at this time no treatment has been proven effective to stop the progression of the disease. The intent of this treatment is to prolong life, temporarily improve symptoms and slows the progression of the disease.
Patients with Interstitial Lung Disease are treated immediately, however, potential side effects of medications are also observed. Take these medications under your doctor’s supervision.
- Corticosteroid, like Prednisone, to reduced inflammation.
- Immune suppressing drugs- sometimes a combination of these drugs are also given to suppress the immune system. Some medications are used to decrease fibrosis and prolong survival.
- Antibiotics- your physician may prescribe antibiotics for infection.
Aids the client to have an easier time breathing and to prevent complications from Hypoxemia (lower level of oxygen in blood).
Is a program with the purpose of improving daily function and well-being of patients with Interstitial Lung Disease. This therapy also teaches proper breathing techniques for lung efficiency and to relieve breathing problems. It also provides lessons on lung disease, and nutritional and psychological counseling.
Usually with a single lung, a lung transplant is considered as a last option for a patient with severe Interstitial Lung Disease and has not recovered after medical treatment. It is possible for patients under the age of 65 years and for those without other significant medical conditions.
Interstitial lung disease has a high rate of morbidity and mortality due to lung injury and fibrosis. Patients usually live for less than 3 years after being diagnosed. Since it is irreversible and fibrosis causes permanent structural damage to the lungs, medications cannot actually treat the disease, but only slow down the symptoms. This disease is most often fatal.