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Idiopathic pulmonary fibrosis

Abstract

Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive lung disease characterized by progressive lung scarring and the histological picture of usual interstitial pneumonia (UIP). It is associated with increasing cough and dyspnoea and impaired quality of life. IPF affects 3 million people worldwide, with incidence increasing dramatically with age. The diagnostic approach includes the exclusion of other interstitial lung diseases or overlapping conditions and depends on the identification of the UIP pattern, usually with high-resolution CT; lung biopsy might be required in some patients. The UIP pattern is predominantly bilateral, peripheral and with a basal distribution of reticular changes associated with traction bronchiectasis and clusters of subpleural cystic airspaces. The biological processes underlying IPF are thought to reflect an aberrant reparative response to repetitive alveolar epithelial injury in a genetically susceptible ageing individual, although many questions remain on how to define susceptibility. Substantial progress has been made in the understanding of the clinical management of IPF, with the availability of two pharmacotherapeutic agents, pirfenidone and nintedanib, that decrease physiological progression and likely improve progression-free survival. Current efforts are directed at identifying IPF early, potentially relying on combinations of biomarkers that include circulating factors, demographics and imaging data.

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Figure 1: Alveolar damage in idiopathic pulmonary fibrosis.
Figure 2: A proposed pathogenetic model of idiopathic pulmonary fibrosis.
Figure 3: Suggested approach for the diagnosis of IPF.
Figure 4: HRCT images from two patients with IPF.
Figure 5: Honeycombing typical in UIP.
Figure 6: Idiopathic pulmonary fibrosis and emphysema.
Figure 7: Idiopathic pulmonary fibrosis and lung cancer.
Figure 8: Emerging biomarkers in IPF.

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Acknowledgements

F.J.M. has been supported by grants from the National Heart, Lung and Blood Institute. The authors thank W.D. Travis (Memorial Sloan Kettering Cancer Center) and N. Narula (Weill Cornell Medicine) for assistance in preparing Figure 5.

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Introduction (F.J.M.); Epidemiology (H.R.C.); Mechanisms/pathophysiology (A.P. and M.S.); Diagnosis, screening and prevention (L.R. and F.J.M); Management (G.R., H.T. and F.J.M.); Quality of life (J.J.S.); Outlook (A.U.W.); Overview of the Primer (F.J.M.).

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Correspondence to Fernando J. Martinez.

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Competing interests

F.J.M. has received personal fees from the American College of Chest Physicians, American Thoracic Society, Astra Zeneca, Boehringer Ingelheim, Genentech/Roche, GlaxoSmithKline, Novartis, Patara and Pearl; he has made continuing medical education presentations to AstraZeneca, Boehringer Ingelheim, Miller Communications, the National Association for Continuing Education, Prime, the University of Alabama at Birmingham and UpToDate; he has served on steering committees for studies supported by Afferent, Astra Zeneca, Bayer, Boehringer Ingelheim, Gilead and GlaxoSmithKline; and he has served on the data and safety monitoring board for studies supported by Biogen, Boehringer Ingelheim, Genentech and GlaxoSmithKline. H.R.C. has received personal fees from aTyr Pharmaceuticals, Bayer, Blood Therapeutics, Boehringer Ingelheim, Bristol-Myers Squibb, Genoa, ImmuneWorks, Moerae Matrix, Navitor, Parexel, Patara, PharmAkea, Prometic, Takeda and Toray. G.R. has received personal fees and other fees from Boehringer Ingelheim, Bristol-Myers Squibb, FibroGen, Gilead, Patara, Promedior, Roche/Genentech, Sanofi, United Therapeutics, UCB and Veracyte outside the submitted work. L.R. has received grants and personal fees from InterMune, and he has received personal fees from Asahi Kasei, Bayer, Biogen, Boehringer Ingelheim, Celgene, FibroGen, Global Blood Therapeutics, ImmuneWorks, Promedior, Pliant Therapeutics, Roche and Sanofi Aventis. M.S. is contributing to the adjudication committee for a clinical trial conducted by Celgene. J.J.S. reports consulting for Global Blood Therapeutics and serving on the unbranded speaker's bureau for Boehringer Ingelheim and Genentech. H.T. has received personal fees from Abbott, Actelion Pharmaceuticals, Astellas Pharma, AstraZeneca, Bayer, Eli Lilly, Fukuda Denshi, GlaxoSmithKline, KYORIN Pharmaceutical, Meiji Seika Pharma, Novartis, Ono Pharmaceutical, Pfizer, Philips Respironics GK, Taiho Phamaceutical, Teijin Pharma and Terumo; he has received personal fees and other fees from Asahi Kasei Pharma, Boehringer Ingelheim, Chugai Pharmaceutical and Shionogi & Co outside the submitted work. A.U.W. has received personal fees from Actelion, Bayer, Boehringer Ingelheim, Chiesi and InterMune/Roche. A.P. declares no competing interests.

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‘Velcro-like’ sounds in idiopathic pulmonary fibrosis. Fine, high-pitched bibasilar inspiratory crackles are the most specific among the physical signs of idiopathic pulmonary fibrosis at presentation. (WAV 78 kb)

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Martinez, F., Collard, H., Pardo, A. et al. Idiopathic pulmonary fibrosis. Nat Rev Dis Primers 3, 17074 (2017). https://doi.org/10.1038/nrdp.2017.74

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