Types of Pulmonary Fibrosis

Pulmonary fibrosis (PF) is characterized by scarring, or fibrosis, in the lungs. Scar tissue development can interfere with the lungs’ ability to deliver oxygen to the bloodstream, as well as with their capacity to inflate and deflate.

Pulmonary fibrosis can be divided into several types, depending on its cause.

Idiopathic PF

Idiopathic pulmonary fibrosis, or IPF, is the most common form of PF. It is estimated to affect as many as one in every 5,000 people worldwide, with approximately 50,000 cases being diagnosed every year.

In this specific type of PF, the underlying cause of lung tissue scarring is not known, hence the designation idiopathic, which means “of unknown origin.” IPF tends to develop in people ages 50 and older, and it is more common in males than females. Other risk factors for IPF include genetics, acid reflux, and cigarette smoking.

Familial PF

In some cases, there is a tendency for PF to run in certain families. Such a pattern suggests that genetics are a cause of fibrosis in these cases, which are referred to as familial pulmonary fibrosis.

This familial form of the disease, which generally is considered when two people in the same biological family develop IPF and/or any other form of idiopathic interstitial pneumonia, is much less common than IPF. To date, only about 100 families have been confirmed to be affected by this specific form of the disease.

Symptoms and treatment of familial PF are similar to those of IPF. Notably, because of increased awareness, people with a family history of the disease may be able to be diagnosed earlier, which is beneficial to more favorable outcomes.

PF associated with other diseases

PF can also develop in association with other disorders, including several autoimmune diseases — conditions where the body’s immune system mistakenly attacks its own tissues — like rheumatoid arthritis and scleroderma. Some infections, such as COVID-19, can also lead to the onset of PF.


Last updated: Sept. 17, 2021


Pulmonary Fibrosis News is strictly a news and information website about the disease. It does not provide medical advice, diagnosis, or treatment. This content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website.

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