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Last reviewed: 28 Oct 2023
Last updated: 07 Aug 2020



History and exam

Key diagnostic factors

  • pain
  • edema or swelling
  • skin discoloration
  • crepitus (gas gangrene)
More key diagnostic factors

Other diagnostic factors

  • diminished pedal pulses and ankle-brachial index (ischemic gangrene)
  • low-grade fever and chills (infectious gangrene)
Other diagnostic factors

Risk factors

  • diabetes mellitus
  • atherosclerosis (ischemic gangrene)
  • smoking (ischemic gangrene)
  • renal disease
  • drug and alcohol abuse
  • malignancy
  • trauma or abdominal surgery (infectious gangrene)
  • contaminated wounds (infectious gangrene)
  • immunosuppression (infectious gangrene)
  • malnutrition (infectious gangrene)
  • hypercoagulable states (ischemic gangrene)
  • prolonged application of tourniquets (ischemic gangrene)
  • community-acquired MRSA
More risk factors

Diagnostic investigations

1st investigations to order

  • CBC
  • comprehensive metabolic panel
  • serum LDH
  • coagulation panel
  • blood cultures
  • serum CRP
  • plain x-rays
  • CT of affected site
  • MRI of affected site
  • Doppler ultrasonography
More 1st investigations to order

Investigations to consider

  • surgical exploration and skin biopsy
  • CT angiography
  • magnetic resonance angiography (MRA)
  • CT chest and abdomen
  • antinuclear antibodies (ANA), lupus anticoagulant, anticardiolipin, and anti beta2 glycoprotein-1 antibodies
  • serum cold agglutinins
  • serum cryofibrinogens
  • plasma cryoglobulin
More investigations to consider

Treatment algorithm


necrotizing fasciitis awaiting confirmation of microbial culture and sensitivity results


confirmed type I necrotizing fasciitis (polymicrobial)

confirmed type II necrotizing fasciitis (monomicrobial)

gas gangrene

ischemic gangrene



Jason Jacob, MD

Attending Physician

Assistant Director

Department of Medicine

Hartford Hospital




JJ declares that he has no competing interests.

Robert J. Gionfriddo, DO

Assistant Director

Department of Medicine

Hartford Hospital




RJG declares that he has no competing interests.


Dr Jason Jacob and Dr Robert J. Gionfriddo would like to gratefully acknowledge Dr William Tennant, Dr Badr Aljabri, Dr Mohammed Al-Omran, Dr Jose Contreras-Ruiz, and Dr Iris Galvan-Martinez, the previous contributors to this topic.


WT, BA, MA, JC, and IG declare that they have no competing interests.

Peer reviewers

Meryl Davis, MD

Consultant Vascular Surgeon

Royal Free Hampstead




MD declares that she has no competing interests.

Charles Fox, MD

Vascular Surgeon

Department of Surgery

Walter Reed Army Medical Center




CF declares that he has no competing interests.

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