Last reviewed: 25 Oct 2020
Last updated: 09 Jan 2020



History and exam

Key diagnostic factors

  • fever or low body temperature
  • tachypnea
  • tachycardia
  • bradycardia (neonates and infants)
  • altered mental state or behavior
  • decreased peripheral perfusion
  • change in usual pattern of activity or feeding in a neonate
  • dry diapers/decreased urine output
  • mottling of the skin, ashen appearance, cyanosis
  • low oxygen saturation
  • vasoplegia
  • nonblanching purpuric rash

Other diagnostic factors

  • hypotension
  • specific focal signs and symptoms reflecting underlying pathology

Risk factors

  • immunodeficiency
  • comorbidities
  • male sex
  • younger age (especially neonates)
  • perinatal risk factors for infection (neonates)
  • healthcare-associated factors (neonates)
  • recent surgery or other invasive procedures
  • breached skin integrity

Diagnostic investigations

1st investigations to order

  • CBC with differential
  • serum glucose
  • blood culture
  • urinalysis
  • urine culture
  • blood gases
  • serum lactate
  • serum electrolytes
  • serum creatinine
  • LFTs
  • coagulation studies
  • CRP
  • CXR
More 1st investigations to order

Investigations to consider

  • lumbar puncture
  • meningococcal polymerase chain reaction analysis
  • bronchoalveolar lavage culture
  • herpes simplex virus (HSV) polymerase chain reaction (blood and cerebrospinal fluid)
More investigations to consider

Emerging tests

  • serum procalcitonin
  • emerging biomarkers
  • PhenoTest™ BC Kit
More emerging tests

Treatment algorithm



Paediatric Intensive Care Unit

King’s College Hospital




AD declares that he has no competing interests.

Dr Akash Deep would like to gratefully acknowledge Dr Jeremy Tong and Dr Adrian Plunkett, previous contributors to this topic.


JT and AP are authors involved in the Pediatric Sepsis Six initiative, cited in this topic.

Peer reviewersVIEW ALL

Professor of Paediatric Immunology & Infectious Diseases

Director, NIHR Wellcome Trust Clinical Research Facility

University of Southampton




SNF declares that he has no competing interests.

Assistant Professor

Texas Children's Hospital and Baylor College of Medicine




MP declares that he has no competing interests.

Faculty, Pediatric Critical Care Medicine

Seattle Children's Hospital

University of Washington School of Medicine




JJZ receives research grant support from NIH/NICHD and ImmuneXpress; travel reimbursement from the Society of Critical Care Medicine to attend board meetings; and royalties from Elsevier for action as a co-editor for the textbook Pediatric Critical Care.

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