Last reviewed: 5 Nov 2021
Last updated: 03 Dec 2020



History and exam

Key diagnostic factors

  • high (>101°F [>38°C]) or low (<96.8°F [<36°C]) temperature
  • tachycardia
  • tachypnea
  • acutely altered mental status
  • poor capillary refill, mottling of the skin, or ashen appearance
  • signs associated with specific source of infection
  • low oxygen saturation
  • arterial hypotension
  • decreased urine output
  • cyanosis

Risk factors

  • underlying malignancy
  • age >65 years
  • immunocompromise
  • hemodialysis
  • alcoholism
  • diabetes mellitus
  • recent surgery or other invasive procedures
  • breached skin integrity
  • indwelling intravenous or urinary catheters
  • intravenous drug use
  • pregnancy
  • urban residence
  • lung disease
  • male sex
  • non-white ancestry
  • winter season

Diagnostic investigations

1st investigations to order

  • CBC with differential
  • BUN and serum electrolytes
  • serum creatinine
  • liver function tests
  • coagulation studies (INR, activated PTT)
  • serum glucose
  • lactate levels
  • CRP
  • blood culture
  • other cultures (e.g., of sputum, stool, urine, wounds, catheters, prosthetic implants, epidural sites, pleural or peritoneal fluid)
  • arterial blood gas (ABG) or venous blood gas (VBG)
  • chest x-ray
  • ECG

Investigations to consider

  • lumbar puncture
  • echocardiogram (transthoracic or transesophageal)
  • ultrasound scan
  • CT chest or abdomen
  • serum procalcitonin

Treatment algorithm



Andre C. Kalil, MD, MPH, FACP, FIDSA, FCCM


Department of Internal Medicine

Division of Infectious Diseases

University of Nebraska Medical Center




ACK declares that he has no competing interests. ACK is an author of references cited in this topic.

Kelly Cawcutt, MD

Assistant Professor

Department of Internal Medicine

Division of Pulmonary, Critical Care, Sleep & Allergy

University of Nebraska Medical Center




KC declares that she has no competing interests.


Professor Andre Kalil and Dr Kelly Cawcutt would like to gratefully acknowledge Dr Ron Daniels, Dr Matt Inada-Kim, Dr Aamir Saifuddin, Dr Tim Nutbeam, Dr Edward Berry, Dr Lewys Richmond, and Dr Paul Kempen, previous contributors to this topic.


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, LR, and PK declare that they have no competing interests.

Peer reviewers

Steven M. Opal, MD, FIDSA

Professor of Medicine

Infectious Disease Division

Rhode Island Hospital

Alpert Medical School of Brown University




SMO declares that he has no competing interests.

Laura Evans, MD, MSc, FCCP, FCCM

Associate Professor

NYU School of Medicine

Medical Director of Critical Care

Bellevue Hospital Center

New York



LE serves as the guidelines co-chair and on the steering committee of the Surviving Sepsis Campaign.

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