Interstitial Lung Disease (ILD)

About Interstitial Lung Disease (ILD)

What Is Interstitial Lung Disease?

Interstitial lung disease (ILD) is an umbrella term for a large group of chronic lung disorders that affect the alveoli (air sacs) in the lungs. 

The lining of the alveoli (the interstitium) is where oxygen is absorbed into the bloodstream. Healthy alveoli expand and contract with ease. In patients with ILD, progressive inflammation or scarring (pulmonary fibrosis) make it hard for the alveoli to expand and absorb enough oxygen.

What Are the Symptoms of ILD?

ILD symptoms usually begin with shortness of breath with exertion during tasks like exercise, walking, or climbing stairs. Over time, shortness of breath can occur with minimal activity or at rest. Additional symptoms can include:

  • Dry cough
  • Fatigue
  • Weakness
  • Chest discomfort
  • Shallow/labored/fast breathing
  • Bleeding in lungs
  • Loss of appetite
  • Weight loss

The severity of ILD symptoms can range from very mild symptoms to severe breathing issues. Mild ILD symptoms can also suddenly become much worse.

What Are the Causes of ILD?

There are many known causes of interstitial lung disease:

  • Exposure to environmental hazards in the home or workplace:
    • Asbestos
    • Molds
    • Bird droppings
    • Coal, cotton, or silica dust
  • Connective tissue diseases:
    • Lupus
    • Scleroderma
    • Rheumatoid arthritis
  • Use of certain medications
  • Radiation treatments
  • Smoking
  • GERD
  • Family history

In some cases, the cause is unknown. In these cases, the disease is called idiopathic ILD. There are a number of idiopathic ILDs, though the most common one is idiopathic pulmonary fibrosis (IPF).

How Is ILD Diagnosed?

Because there are many types of ILD, diagnosis can be challenging. Your doctors will perform a thorough evaluation that will include discussing your family history and several diagnostic procedures to help determine the correct diagnosis.

The initial evaluation typically includes: 

  • Physical exam
  • Blood tests
  • Chest X-ray
  • Chest CT scan 
  • Pulmonary function testing


For some diagnoses, a lung biopsy may be necessary. A bipopsy takes a small sample of tissue for study. Lung biopsies can be performed in two ways: 

  • Bronchoscopy: A flexible tube called a bronchoscope is inserted through a nostril and advanced into the lungs to obtain a small sample of lung tissue. The patient receives an anesthetic to maintain comfort during this procedure.
  • Surgical Biopsy: Not all ILD types can be diagnosed using bronchoscopy. In these cases, a surgical lung biopsy may be necessary.

Additional Tests

  • Exercise testing such as a cardiopulmonary exercise test and a six-minute walking test can gauge the severity of the disease.

Once diagnostic testing is complete, each case is presented and discussed at a multidisciplinary ILD conference. A group of expert clinicians and researchers will determine the correct diagnosis and develop an appropriate treatment plan.

Can ILD Be Prevented?

Some types of ILD cannot be prevented, such as genetic types of ILD or idiopathic ILD. But for types of ILD with known causes, there are ways you can reduce your risk, including:

  • Not smoking or quitting smoking
  • Wearing proper protection (like a respirator) when working with harmful substances like asbestos or mold

Can ILD Be Cured?

There is no cure for ILD, so treatment focuses on slowing the progression of the disease while improving overall quality of life.

How Is ILD Treated?

The treatment of ILD depends on the degree of inflammation and scarring.

Inflammation may be reversible or controlled with medical therapies such as: 

  • Steroids (like prednisone) 
  • Immunosuppressive agents
  • Azathioprine
  • Mycophenolate mofetil
  • Cytoxan

The decision to use steroids or immunosuppressive medications depends on each patient's unique situation. An ILD specialist will discuss the risks and benefits of potential treatments with each patient.

For patients with little or no inflammation but with scarring (fibrosis), steroids or immunosuppressive therapy are unlikely to help because lung scarring is usually irreversible. But some new and promising treatments are being explored for the treatment of idiopathic pulmonary fibrosis. Antifibrotic agents may help reduce scarring in patients with IPF.

Supportive therapies for ILD include:

  • Supplemental oxygen
  • Pulmonary rehabilitation
  • Treatment of coexisting pulmonary conditions, such as:
    • Chronic obstructive pulmonary disease (COPD) 
    • Obstructive sleep apnea
    • Complications of ILD (such as pulmonary hypertension)

Lung Transplantation

In severe cases where ILD cannot be managed with medication, lung transplantation may be recommended. 

Columbia Interstitial Lung Disease Program

The Interstitial Lung Disease Program (ILD) at Columbia University Irving Medical Center/NewYork-Presbyterian is a comprehensive multidisciplinary program for patients with many types of interstitial lung disease (ILD). As part of the Price Family Center for Comprehensive Chest Care, we offer world-class diagnosis and care, coordination of care with local providers, and convenient access to important services in one location.

Learn More About the Columbia Interstitial Lung Disease Program