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Last reviewed: 16 Mar 2025
Last updated: 10 Dec 2024

Summary

Definition

History and exam

Key diagnostic factors

  • congestive heart failure, pneumonia, and malignancy
  • dyspnea
  • dullness to percussion

Other diagnostic factors

  • pleuritic chest pain
  • cough
  • absent or decreased breath sounds
  • decreased or absent tactile fremitus

Risk factors

  • congestive heart failure
  • pneumonia
  • malignancy
  • pulmonary embolism
  • recent coronary artery bypass graft surgery
  • recent myocardial infarction
  • occupational lung disease
  • rheumatoid arthritis
  • systemic lupus erythematosus
  • renal failure
  • drug-induced pleural effusion
  • recent ovarian stimulation treatment
  • chylothorax

Diagnostic tests

1st tests to order

  • posteroanterior and lateral chest x-ray
  • pleural ultrasound
  • LDH and protein in pleural fluid and serum
  • red blood cell count in pleural fluid
  • WBC count and differential of pleural fluid
  • cytology of pleural fluid
  • culture of pleural fluid
  • pH of pleural fluid
  • glucose in pleural fluid
  • protein gradient
  • CBC
  • CRP
  • blood culture
  • sputum Gram stain and culture
  • N-terminal pro-brain natriuretic peptide (NT-pro-BNP) in pleural fluid

Tests to consider

  • pleural fluid cholesterol level
  • thoracic CT scan
  • thoracic MRI
  • helical CT scan
  • amylase in pleural fluid
  • adenosine deaminase (ADA) level in pleural fluid
  • lipid analysis of pleural fluid
  • antinuclear antibody (ANA) analysis of pleural fluid
  • thoracoscopy
  • bronchoscopy
  • pleural biopsy
  • interferon-gamma in pleural fluid and real-time polymerase chain reaction of pleural fluid
  • procalcitonin

Emerging tests

  • tumor markers in pleural fluid

Treatment algorithm

Contributors

Authors

Orhan Orhan, MBBS, BSc, FRCP, SFHEA, MSc

Consultant Respiratory Physician

Chelsea and Westminster Hospital NHS Foundation Trust

London

UK

Disclosures

OO declares that he has no competing interests.

Acknowledgements

Dr Orhan Orhan would like to gratefully acknowledge Drs Clare Ross, Philip W. Ind, Anob M. Chakrabarti, Richard Light, Amber Degryse, Rachel J. Davies, and Peter M. George, previous contributors to this topic.

Disclosures

RL received speaking fees provided by Cardinal Health; owned stock in Denver Biomaterials until it was purchased by Cardinal Health; received fees for consulting from Denver Biomaterials; and is an author of references cited in this topic. CR, PWI, AMC, AD, RJD, and PMG declare that they have no competing interests.

Peer reviewers

Y.C. Gary Lee, MBChB, PhD, FCCP, FRACP

Consultant Chest Physician and Senior Lecturer

Oxford Centre for Respiratory Medicine and University of Oxford Churchill Hospital

Oxford

UK

Disclosures

YCGL declares that he has no competing interests.

Clare Hooper, MBBS

Pleural Research Registrar

North Bristol Lung Centre

Southmead Hospital

Westbury on Trym

Bristol

UK

Disclosures

CH declares that she has no competing interests.

Steven Sahn, MD

Professor of Medicine and Director

Division of Pulmonary/Critical Care/Allergy/Sleep Medicine

Medical University of South Carolina

Charleston

SC

Disclosures

SS declares that he has no competing interests.

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