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Last reviewed: 9 Mar 2025
Last updated: 01 Apr 2025

Summary

Definition

History and exam

Key diagnostic factors

  • presence of risk factors
  • dyspnoea
  • cough
  • crackles

Other diagnostic factors

  • weight loss, fatigue, and malaise
  • clubbing

Risk factors

  • advanced age
  • male sex
  • family history
  • gene mutations and nucleotide polymorphisms
  • cigarette smoking
  • occupational and environmental exposures
  • gastro-oesophageal reflux
  • viral infection
  • bacterial infection
  • diabetes

Diagnostic investigations

1st investigations to order

  • CXR
  • high-resolution CT (HRCT) chest
  • pulmonary function tests

Investigations to consider

  • surgical lung biopsy
  • bronchoalveolar lavage (BAL)
  • trans-bronchial lung biopsy and cryobiopsy
  • CRP
  • erythrocyte sedimentation rate (ESR)
  • anti-nuclear antibody immunofluorescence
  • rheumatoid factor
  • anti-cyclic citrullinated peptide
  • myositis panel

Treatment algorithm

Contributors

Authors

Mary Elizabeth Kreider, MD, MS

Associate Professor of Clinical Medicine

Pulmonary, Allergy, and Critical Care Division

Perelman School of Medicine

University of Pennsylvania

Philadelphia

PA

Disclosures

MEK is serving as site principal investigator for Bellerophon and United Therapeutics for interstitial lung disease (ILD) studies. Her institution receives payments for those trials.

Jake G. Natalini, MD, MS

Assistant Professor of Medicine

Pulmonary, Critical Care, and Sleep Division

NYU Grossman School of Medicine

New York University

New York

NY

Disclosures

JGN is serving as site principal investigator for a CareDx clinical diagnostics study in lung transplantation. His institution receives payments for this trial. He has also previously provided consulting services to CareDx.

Acknowledgements

Dr Mary Elizabeth Kreider and Dr Jake G. Natalini would like to gratefully acknowledge Dr Judd David Flesch, Dr Gregory Tino, and Dr Jeffrey C. Munson, previous contributors to this topic.

Disclosures

GT has served as a consultant for InterMune. GT has served as a principal investigator for clinical trials in idiopathic pulmonary fibrosis. JCM and JDF declare that they have no competing interests.

Peer reviewers

Stephen Nathan, MD

Medical Director

Lung Transplant & Advanced Lung Disease Program

Inova Fairfax Hospital

Falls Church

VA

Disclosures

SN is an author of a reference cited in this monograph.

Athol Wells, MD, FRCP

Professor of Respiratory Medicine

Interstitial Lung Disease Unit

Royal Brompton Hospital

London

UK

Disclosures

AW declares that he has no competing interests.

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