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Last reviewed: 9 Mar 2025
Last updated: 12 Jun 2024

Summary

Definition

History and exam

Key diagnostic factors

  • risk factors
  • signs associated with specific source of infection
  • high early warning score (e.g., NEWS2 5 or more)
  • tachypnoea (NEWS2)
  • high or low temperature, sometimes with rigors (NEWS2)
  • tachycardia (NEWS2)
  • acutely altered mental status (NEWS2)
  • low oxygen saturation (NEWS2)
  • hypotension (NEWS2)
  • oliguria
  • poor capillary refill, mottling of the skin, or ashen appearance
  • cyanosis

Other diagnostic factors

  • malaise/lethargy
  • nausea/vomiting/diarrhoea
  • purpura fulminans
  • ileus
  • jaundice

Risk factors

  • age >65 years
  • immunocompromise
  • indwelling lines or catheters
  • recent surgery or other invasive procedures
  • haemodialysis
  • diabetes mellitus
  • intravenous drug misuse
  • alcohol dependency
  • pregnancy
  • breached skin integrity
  • urban residence
  • lung disease
  • male sex
  • non-white ancestry
  • winter season

Diagnostic investigations

1st investigations to order

  • blood cultures
  • serum lactate
  • hourly urine output
  • full blood count
  • urea and electrolytes (including creatinine)
  • serum glucose
  • C-reactive protein
  • serum procalcitonin
  • clotting screen
  • liver function tests
  • blood gas
  • ECG

Investigations to consider

  • urine analysis
  • chest x-ray
  • cultures from multiple sources
  • lumbar puncture
  • computed tomography
  • ultrasound
  • urine antigen testing
  • viral swabs
  • HIV screen
  • echocardiogram

Treatment algorithm

Contributors

Expert advisers

Alexander Alexiou, MB, BS, BSc, DCH, FRCEM, Dip IMC RCSEd

Emergency Medicine Consultant

Physician Response Unit Consultant

Barts Health NHS Trust

London’s Air Ambulance

Royal London Hospital

London

UK

Disclosures

AA declares that he has no competing interests.

Clovis Rau, MBBS, BSc, FRCEM, DipIMC

Specialty Registrar Emergency Medicine (ST6)

Barnet Hospital

Royal Free NHS Foundation Trust

London

UK

Disclosures

CR declares that he has no competing interests.

Acknowledgements

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

Ron Daniels MBChB, FRCA

Chief Executive

United Kingdom Sepsis Trust

Chief Executive

Global Sepsis Alliance

Programme Director

Survive Sepsis

Consultant in Critical Care and Anaesthesia

Heart of England NHS Foundation Trust

Birmingham

UK

Matt Inada-Kim MBBS, FRCP

Consultant Acute Physician & Sepsis Lead

Department of Acute Medicine

Royal Hampshire County Hospital

Hampshire Hospitals NHS Foundation Trust

Winchester

UK

Aamir Saifuddin BMBCh, BA, MRCP, AFFMLM

Specialty Registrar in Gastroenterology and General Medicine

Maidstone and Tunbridge Wells NHS Trust

UK

Tim Nutbeam MSc, Dip IMC FRCEM

Consultant in Emergency Medicine

Clinical Academic

University of Plymouth

Lead Doctor

Devon Air Ambulance Trust

Derriford Hospital

Plymouth

UK

Edward Berry MBChB, MCEM

Specialty Registrar in Emergency Medicine

Derriford Hospital

Plymouth

UK

Disclosures

RD has received payment for consultancy on sepsis from Kimal Plc, manufacturers of vascular access devices, from the Northumbria Partnership, a patient safety collaborative, and, where annual leave or other income was compromised in fulfilling his charity duties, from the UK Sepsis Trust. RD has received sponsorship to attend and speak at one meeting from Abbott Diagnostics. He is CEO of the UK Sepsis Trust and Global Sepsis Alliance, and advises HM Government, the World Health Organization, and NHS England on sepsis. Each of these positions demands that he express opinion on strategies around the recognition and management of sepsis. MIK is a national clinical advisor on sepsis to NHS England and a national clinical advisor on deterioration to NHS Improvement. He was reimbursed for a slide set by Relias Learning. AS is the clinical fellow to the National Medical Director at NHS Improvement. AS has been sponsored on two occasions by Dr Falk Pharma UK to attend specialist gastroenterology conferences abroad; there was no contractual obligation to disseminate product information. TN is a clinical adviser to the UK Sepsis Trust. EB declares that he has no competing interests.

Peer reviewers

Matt Inada-Kim, MBBS, FRCP

Consultant Acute Physician & Sepsis Lead

Department of Acute Medicine

Royal Hampshire County Hospital

Hampshire Hospitals NHS Foundation Trust

Winchester

UK

Disclosures

MIK is a national clinical advisor on sepsis to NHS England and a national clinical advisor on deterioration to NHS Improvement. He was reimbursed for a slide set by Relias Learning.

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