Last reviewed: July 2020
Last updated: July  2020

Summary

Definition

History and exam

Key diagnostic factors

  • dyspnoea
  • cough
  • increased sputum purulence and volume
  • wheeze
  • chest tightness/chest pain
  • tachypnoea
  • tachycardia
  • risk factors
  • cor pulmonale

Other diagnostic factors

  • signs of respiratory failure
  • fever
  • gastro-oesophageal reflux and/or swallowing dysfunction

Risk factors

  • bacterial infection
  • gastro-oesophageal reflux and/or swallowing dysfunction
  • viral infection
  • pollutants
  • atypical bacterial infection
  • change in weather

Diagnostic investigations

1st investigations to order

  • arterial blood gas (in hospital)
  • pulse oximetry (in hospital and in the community) 
  • ECG (in hospital and in the community if available)
  • FBC with platelets (in hospital)
  • urea, electrolytes, and creatinine (in hospital)
  • CRP (in hospital)
  • CXR (in hospital)
  • sputum microscopy, culture, and Gram stain (in hospital)
  • vitamin D (in hospital or in the community)
Full details

Investigations to consider

  • blood cultures
  • respiratory virus diagnostics
  • cardiac troponin
  • serum theophylline level
  • pro-brain natriuretic peptide (BNP)
  • CT scan of chest
  • spirometry
Full details

Treatment algorithm

Contributors

Expert advisersVIEW ALL

Honorary Professor of Respiratory Sciences

University of Leicester

Respiratory Consultant

Glenfield Hospital

Leicester

UK

Biography

JB is Chair of the British Thoracic Society.

Disclosures

JB declares that he has no competing interests.

Specialty Registrar in Respiratory Medicine

Glenfield Hospital

Leicester

UK

Disclosures

RJR received sponsorship from AstraZeneca to attend a conference, May 2018 (covering travel, accommodation, and conference fee).

BMJ Best Practice would like to gratefully acknowledge the previous team of expert contributors, whose work has been retained in parts of the content:

Carolyn L. Rochester MD

Associate Professor

Yale University School of Medicine

New Haven

VA Connecticut Healthcare System

West Haven

CT 

Richard A. Martinello MD

Associate Professor

Yale University School of Medicine

New Haven

Veterans Health Administration

Office of Public Health

West Haven

CT 

Disclosures

CLR serves on the COPD scientific advisory board for GlaxoSmithKline Pharmaceuticals but has no competing interests pertaining to this publication. RAM declares that he has no competing interests. 

Peer reviewersVIEW ALL

Consultant Respiratory Physician

Royal Victoria Infirmary

Newcastle upon Tyne

UK

Disclosures

CE declares that he has no competing interests.

Section Editor, BMJ Best Practice 

Disclosures

EQ declares that she has no competing interests.

Lead Section Editor, BMJ Best Practice

Disclosures

TAO declares that she has no competing interests.

Comorbidities Editor, BMJ Best Practice

Disclosures

JC declares that she has no competing interests.

Drug Editor, BMJ Best Practice

Disclosures

AM declares that he has no competing interests.

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