A doctor showing a patient a CT scan of pulmonary fibrosis.

What is Pulmonary Fibrosis?

In its simplest meaning, pulmonary fibrosis means
lung scarring; it is a build-up of scar tissue in the lung,
making breathing more difficult.

Key facts

  • Interstitial lung disease (ILD) is a term that covers many different conditions of the lung, 
    some of which can be associated with scarring of the lung tissue
  • Pulmonary fibrosis is the scarring of the lungs, which can be progressive
  • In some patients, the cause of fibrosis is not identified

Pulmonary fibrosis is also a term that’s used to refer to a disease that is found in the interstitium of the lungs. It falls into an even larger group of diseases called ILDs. Why? Because the scarring is found in the interstitium of the lungs; that is, the network of tissue that supports the air sacs of your lungs. 

There are hundreds of different interstitial lung diseases or ILDs. Some ILDs cause mostly scarring; other ILDs cause mostly inflammation. Others cause a mix of both. If you have pulmonary fibrosis, it means that you have a type of ILD that causes lung scarring.

An inside look: what happens to lungs affected by pulmonary fibrosis

Tiny air sacs (known as alveoli) and blood vessels of the lungs are responsible for providing oxygen to all parts of the body. As scarring of the lung tissue and air sacs develops, it becomes harder for oxygen to pass through the lungs and into the bloodstream. The symptoms of pulmonary fibrosis vary from person to person, but in some people, progression of lung damage can result in shortness of breath and eventually lead to the body’s organs not getting enough oxygen to work properly. It's important to be aware of all the common symptoms of pulmonary fibrosis.

How did I get pulmonary fibrosis?

Pulmonary fibrosis can be caused by various environmental factors as well as certain diseases or chronic conditions. For example, people with interstitial lung disease may also have pulmonary fibrosis. ILDs with pulmonary fibrosis are a challenging group of diseases that affect the interstitium of the lung (the space between the air sacs in the lung) and lead to the formation of scar tissue.

Conditions or diseases that can involve pulmonary fibrosis include:

  • Idiopathic pulmonary fibrosis

  • Scleroderma with ILD

  • Sarcoidosis with ILD

  • Rheumatoid arthritis with ILD

  • Hypersensitivity pneumonitis

  • Sjögren's syndrome with ILD

Find out more about the different conditions associated with pulmonary fibrosis.

When the cause of a person’s pulmonary fibrosis is unknown, the condition is referred to as Idiopathic Pulmonary Fibrosis. 

Because there are so many conditions associated with pulmonary fibrosis, the causes, treatments, and how it affects someone can be different from person to person. 

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