Pleural effusion

Last reviewed: 7 May 2023
Last updated: 25 May 2021

Summary

Definition

History and exam

Key diagnostic factors

  • presence of risk factors
  • dyspnoea
  • dullness to percussion
More key diagnostic factors

Other diagnostic factors

  • pleuritic chest pain
  • cough
  • quieter breath sounds
  • decreased or absent tactile fremitus
Other diagnostic factors

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
More risk factors

Diagnostic investigations

1st investigations to order

  • postero-anterior 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
  • FBC
  • CRP
  • blood culture
  • sputum Gram stain and culture
  • N-terminal pro-brain natriuretic peptide (NT-pro-BNP) in pleural fluid
More 1st investigations to order

Investigations 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
  • thoracoscopy
  • bronchoscopy
  • pleural biopsy
  • interferon-gamma in pleural fluid and real-time polymerase chain reaction of pleural fluid
More investigations to consider

Emerging tests

  • tumour markers in pleural fluid
  • procalcitonin

Treatment algorithm

ACUTE

congestive heart failure

infective

malignant: poor performance status or limited lifespan (Karnofsky score ≤30% or ECOG score of ≥2)

malignant: good performance status (Karnofsky score >30% or ECOG score of 0 or 1)

ONGOING

persistent empyema despite chest tube

recurrent symptomatic malignant effusions

recurrent benign effusion

Contributors

Authors

Orhan Orhan, MBBS BSc MRCP FHEA 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 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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