What is pulmonary fibrosis?

Pulmonary fibrosis is a significant threat across a broad range of ILDs1–4

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Pulmonary fibrosis occurs commonly in a wide range of interstitial lung diseases (ILDs), it can cause irreversible lung damage and is associated with increased mortality.1,3,5,6


In healthy lungs, oxygen is efficiently transferred from alveoli (air sacs) into the bloodstream.2

Pulmonary fibrosis is the build up of scar tissue in the lungs, leading to stiffness, as well as loss of function of alveolar (air sac) tissue, impairing gas exchange and making it difficult for your patients to breathe.2,7

Pulmonary fibrosis causes irreversible lung damage and sustained fibrosis leads to early mortality.3,5


Reprinted from Nature Reviews Disease Primers, 3, Martinez FJ, Collard HR, Pardo A, et al. idiopathic pulmonary fibrosis, 17074, 2017, with permission from Springer Nature.


Pulmonary fibrosis occurs in a wide range of ILDs8

Idiopathic pulmonary fibrosis (IPF)
  • IPF is one of the most common fibrotic ILDs with an estimated prevalence at 8.2–60 cases per 100,000 people.2,6 It is characterized by the presence of continued progression of pulmonary fibrosis1

Help your patients learn about their IPF with our IPF infographic
Download IPF infographic
Connective tissue disease-associated interstitial lung diseases (CTD-ILDs)
  • ILD occurs in ~15% of all patients with connective tissue diseases (CTDs), with higher rates in certain conditions such as systemic sclerosis (>70%) and rheumatoid arthritis (10–20%)1,9
  • Fibrotic ILD often develops early in the course of a CTD and may be the first manifestation of the disease9
Help your patients learn about their systemic sclerosis-associated ILD (SSc-ILD) and rheumatoid arthritis-associated ILD (RA-ILD) with our infographics

Download SSc-ILD infographic     Download RA-ILD infographic

Hypersensitivity pneumonitis (HP)
  • Hypersensitivity pneumonitis is a rare ILD that occurs in people when the body’s immune system overreacts and develops an allergic reaction after breathing in allergens from the environment10
  • The prevalence of ILD associated with HP is ~2.3 cases per 100,000 people11
Help your patients learn about their HP with our infographic below

Download HP infographic

  • Sarcoidosis is a disease of unknown cause that can affect different organs, including the lungs12
  • It is one of the most common fibrotic ILDs, with an estimated prevalence of 30.2 cases per 100,000 people11
Unclassifiable idiopathic interstitial pneumonias (IIP)
  • Unclassifiable ILD is a heterogeneous, poorly defined category of ILD, with clinical features that are intermediate between IPF and non-IPF ILDs13
  • Unclassifiable ILD should prompt regular re-evaluation and search for new information that might increase the confidence in a specific ILD diagnosis,13 as a specific ILD diagnosis may have implication for the prognosis and treatment14
Idiopathic nonspecific interstitial pneumonia (iNSIP)
  • Similar to unclassifiable ILD, the clinical entity iNSIP should be a provisional diagnosis and should prompt further study15

Support your patients by knowing that pulmonary fibrosis occurs in a wide range of ILDs and is associated with an increased mortality1,3,5,6


While each patient with ILD is unique, common pathogenic pathways to pulmonary fibrosis are shared.1,3,7,19

Patients with ILDs develop pulmonary fibrosis via common pathogenic pathways, irrespective of the underlying diagnosis or trigger.1,3,7,19,20

In the early stages of ILD pathogenesis, inflammation and fibrosis can coexist and lead to the development of pulmonary fibrosis.1,7,18,20–22

As ILD progresses, it may develop into progressive pulmonary fibrosis (PPF), leading to increased, self-sustaining fibrosis.7,18,22–24

Pulmonary fibrosis in ILD is driven by inflammation and fibrosis18,22,25,26



Patients should be made aware that the disease course of ILD can be unpredictable, dependent on the ILD diagnosis and disease severity.1,7,33 ILD may become progressive despite standard of care, known as progressive pulmonary fibrosis (PPF) or progressive fibrosing ILD.7,8,19,33–35

Importantly, patients should understand that pulmonary fibrosis causes irreversible lung damage and sustained fibrosis may lead to early mortality.3,5

Nurses may also better educate caregivers as patients may struggle to explain their disease themselves.27

One of the important roles that nurses provide is patient education – be prepared to discuss difficult subjects like the impact of patients' disease and prognosis28,30

What other resources can help you support your patients in their journey with fibrotic ILD?

  • CO2, carbon dioxide; CTD, connective tissue disease; CTD-ILD, connective tissue disease-associated interstitial lung disease; HP, hypersensitivity pneumonitis; IIP, idiopathic interstitial pneumonia; ILD, interstitial lung disease; iNSIP, idiopathic non-specific interstitial pneumonia; IPF, idiopathic pulmonary fibrosis; O2, oxygen; PPF, progressive pulmonary fibrosis; RA-ILD, rheumatoid arthritis-associated interstitial lung disease; SSc-ILD, systemic sclerosis-associated interstitial lung disease.

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