Interstitial Lung Disease (ILD): Symptoms, Causes, Types, and Cure Options
April 8, 2025

Interstitial lung disease (ILD) is another name for pulmonary fibrosis, a condition characterized by scarring and inflammation of the interstitium. This scar can stiffen lung tissue and cause respiratory distress, leading to various symptoms like shortness of breath and a persistent dry cough. ILD may be confined to the lungs or associated with conditions affecting other body parts, such as rheumatoid arthritis and sarcoidosis.
These illnesses share common signs, including a dry cough and shortness of breath. Although they may look similar radiographically (on chest X-rays or CT scans of the chest), ILDs of different causes and conditions have different treatments and outlooks. ILD occurs more commonly in adults, but it is rare in children.
Types
The interstitium thickens in all types of interstitial lung disease. This may result from swelling, scarring, or a fluid buildup. Some ILD types are transient (acute), while others are persistent (chronic).
The following are a few forms of interstitial lung disease:
- Pneumonia with interstices: The interstitium can get infected by bacteria, viruses, or fungi. The leading cause is a bacterium called Mycoplasma pneumonia.
- Idiopathic pulmonary fibrosis: The interstitium begins to produce scar tissue. However, experts are uncertain about its underlying cause.
- Nonspecific interstitial pneumonia: It is a lung condition not specifically linked to a particular bacterium or virus. It is mainly seen in individuals with autoimmune diseases like scleroderma or rheumatoid arthritis.
- Hypersensitivity pneumonitis: This disorder occurs when prolonged exposure to dust, mold, or other airborne irritants leads to inflammation in the lungs.
- Genetic ILD: When an illness is passed down through the family, it is called a genetic ILD. These illnesses include Gaucher’s disease and neurofibromatosis, where tumors develop on nerves.
- Cryptogenic organising pneumonia (COP): COP is an interstitial lung illness that resembles pneumonia but isn’t infectious. Your doctor may diagnose this as organized pneumonia and bronchiolitis obliterans (BOOP).
- Acute interstitial pneumonitis: It is a lung infection that can be life-threatening. This is a severe lung disease that can occur suddenly. People with lung disease often need to be connected to a machine called a ventilator that helps them breathe.
- Sarcoidosis: This condition can lead to interstitial lung disease and swollen lymph nodes. Consequently, it can affect the heart, skin, nerves, and eyes.
- Asbestosis: It is an interstitial lung disorder caused by inhaling asbestos fibers, commonly found in building materials.
Signs
Most ILD sufferers experience symptoms that make breathing challenging, such as:
- Breathing difficulty
- Coughing, usually ineffective
- Reduced capacity for exercise
- Fatigue
- Loss of weight
Symptoms
Breathlessness is the most typical symptom of all interstitial lung diseases. It is also a common symptom of ILD and can worsen over time.
The following are other signs of interstitial lung disease:
- Coughing rarely produces mucus and is often dry.
- Loss of weight, most frequently in those with COP or BOOP.
- The majority of ILDs cause slow-moving development of breathlessness (over months). If you have acute interstitial pneumonitis (in hours or days), your symptoms will appear fast.
Stages
Understanding how ILD progresses is key to managing treatment and anticipating outcomes. Although the disease affects individuals differently, it typically advances through the following stages:
- Early Stage: Individuals may experience mild symptoms that barely affect daily life. Lung function tests might show only slight impairment.
- Moderate Stage: Symptoms like a persistent cough, fatigue, and shortness of breath become more noticeable. Lung function tests usually reveal moderate declines.
- Advanced Stage: Symptoms intensify, making everyday tasks difficult. Lung function significantly drops, and oxygen levels in the blood decrease.
Risk Factors
The cause of most interstitial lung diseases is unknown. Bacteria, viruses, and fungi can cause pneumonia, which is a type of lung infection. You may also get ILD if you regularly inhale something that bothers your lungs. These include:
- Asbestos
- Bird proteins (such as those from exotic birds, chickens, or pigeons)
- Coal dust or other various metal specks of dust from mining operations
- Grain dust from agriculture
- Silica dust
- Talc
Diagnosis
Common symptoms of interstitial lung disease include coughing and shortness of breath. Your doctor usually does imaging tests on your lungs to diagnose the issue.
- A Chest X-ray is a common initial examination for individuals with respiratory issues. In cases of interstitial lung disease, thin lines may be visible in the lungs on the X-ray.
- CT scan produces clear images of the lungs and surrounding structures by taking many chest X-rays. Usually, these tests can detect interstitial lung disease.
- A high-resolution CT scan can provide a clearer view of the interstitium, especially if your doctor suspects interstitial lung disease.
- A lung function test is a way to check how well your lungs are working. You sit inside a sealed plastic booth and breathe through a tube to measure how much air your lungs can inhale and exhale. If you have ILD, your lung capacity might be reduced. As a result, you might be less able to supply oxygen from your lungs into your blood.
- A high-definition CT scan, with specific settings, can provide a clearer view of the interstitium if interstitial lung disease is suspected, aiding in diagnosis.
Complications
Severe interstitial lung disease can lead to serious complications such as high blood pressure in the lungs, respiratory failure, and right-sided heart failure.
Frequently Asked Questions
1. What is the life expectancy of a person with interstitial lung disease?
The current average lifespan for those with this type is 3 to 5 years. With some medicines, depending on how they progress, they may last longer. Other interstitial lung diseases, such as sarcoidosis, can cause patients to live significantly longer.
2. How serious is interstitial lung disease?
Interstitial lung disease (ILD) varies in severity from mild to life-threatening. It damages the lungs permanently, making breathing difficult and lowering oxygen levels, greatly affecting quality of life.