Necrotizing Fasciitis

Necrotizing fasciitis left leg[1]

Necrotizing fasciitis is a rare, severe soft tissue infection typically by Group A streptococci, marked by necrosis of subcutaneous tissues with involvement of the fascia.


During the first 2 days, the following clinical features are present:

Over the next 2 to 3 days, the clinical features include:

  • Edema
  • Formation of hemorrhagic bullae (fluid filled thin walled blisters)
  • Grey discoloration of the skin, indicating necrosis
  • Hardening of the subcutaneous tissues in the fascial planes
  • Crepitus due to production of gas in the tissues.
  • Gangrene
  • Intense pain that disappears soon due to destruction of pain nerve endings

After another 2 days, the following grave complications are seen:


The following investigations are helpful in diagnosing necrotizing fasciitis.

  • Blood tests for white blood cell count, serum sodium levels, C-reactive protein and creatine kinase.
  • Blood urea nitrogen (BUN)
  • Arterial blood gas measurement
  • Bedside finger test: If the skin is open, the index finger can easily pass through the skin layers or if the skin is not broken, a scalpel can be used to perform this test.
  • Blood culture
  • Urinalysis
  • Wound swab culture
  • Tissue biopsy
  • Frozen tissue biopsy
  • Gram staining of the cultures

Imaging techniques for the investigation of necrotizing fasciitis include the following.

  • Soft tissue radiograph
  • Computerized tomography (CT) scan
  • Magnetic resonance imaging (MRI)
  • Ultrasound
  • Infrared spectroscopy for measuring the tissues oxygen saturation


The treatment of necrotizing fasciitis consists of the following.

  • Management of symptoms of shock (by the administration of intravenous fluids and provision of intensive care)
  • Intravenous wide-spectrum antibiotics are given. These include benzyl penicillin with clindamycin and gentamicin, or meropenem and clindamycin, or clindamycin, ciprofloxacin and metronidazole, or tetracycline and third-generation cephalosporins ( such as doxycycline, ceftazidime) or piperacillin/tazobactam.
  • Intravenous Immunoglobulins can also be given in these patients. [6]
  • Surgical debridement or in extreme cases, amputation of the affected part may also be required.
  • VAC (Vacuum Assisted Closure) is currently a popular option for the treatment of necrotizing fasciitis [7] [8].
  • Hyperbaric oxygen therapy has also shown good results in the management of necrotizing fasciitis [9] [10].
  • Skin grafts may be required for surgical or cosmetic benefit in these patients.


The morbidity and mortality rates associated with necrotizing fasciitis are high. If prompt treatment is not given, limb amputation will be required. A mortality rate of 20% to 75% has been found. Permanent disfigurement is the commonest complication of majority of the cases. Average life span of these patients has been found to be 38 to 44 years.


Necrotizing fasciitis is common in cases of chronic infections (chronic liver disease, chronic renal disease) or in immunocompromised individuals, for example, in diabetics, HIV patients, those undergoing cancer chemotherapy or organ transplant patients. Bacteria enter the body through a break in the skin like cuts, abrasions, lacerations or surgical wounds.

The disease is caused by certain bacteria including the following [1] [2]:

It may also be due to opportunistic fungal infections inclding:

Based on etiology, necrotizing fasciitis is classified into following categories:

  • Type I (polymicrobial, more than one type of bacteria are involved, may be aerobic or anaerobic)
  • Type II (monomicrobial, Group A streptococcal infection, occasionally, staphylococci are involved)
  • Type III (monomicrobial, gram negative bacteria are involved).
  • Type IV (fungal infection)


The incidence of the disease is 1:10,000. It is more common in Asian and African countries. A male dominance with a 2-3:1 ratio has been recorded. The disease is rare in children.

The incidence is higher in immunocompromised patients, patients with neutropenia, individuals harboring open wounds, in the elderly, pregnant women and in obese people.

Sex distribution
Age distribution


The toxins (most commonly those released by group A beta hemolytic Streptococci (GABS) and Streptococcal pyrogenic exotoxins (SPEs) A, B, and C) released by the aerobic bacteria breakdown the skin and subcutaneous tissues, invading the deeper structures [3]. They cause the inhibition of immune response of the host and also cause tissue hypoxia, causing the gram negative bacteria to grow into the infected tissues [4]. Vascular occlusion and ischemia follow. The infected tissue eventually begins to die (necrosis) [5]. The bacteria enter the blood stream eventually, causing sepsis and shock.


The following preventive measures are effective in reducing the occurrence of necrotizing fasciitis.

  • Proper tending of open cuts or wounds.
  • Washing hands regularly with soap and plenty of water.
  • Avoiding swimming or other such activities in case of a wound or infection till it heals.
  • Aseptic techniques should be used during surgeries to prevent infection of the wounds
  • Post-op care should be provided to the patients to avoid secondary MRSA infections.


Necrotizing fasciitis refers to the acute infection and necrosis of the fascia, the layer of connective tissue that surrounds most of the body tissues, like muscles, vessels and nerves. The infection is caused by certain bacteria that seem to “eat” the skin and subcutaneous structures of the body, resulting in a grotesque appearance, hence the name “flesh eating disease”.

Patient Information

Necrotizing fasciitis, commonly known as “flesh eating disease” is the disorder in which bacteria enter the body through open wounds. Individuals, in whom the immune defense mechanisms are low, are particularly susceptible to the disease. The bacteria “eat” the skin and the underlying tissues. The structures underneath are exposed.

If infection spreads to a large area and prompt medical care is not provided to the patient, amputation of the affected organ may be required. The patient may even die if not given adequate treatment. As bacteria enter through the breaks in the skin, it is vital to keep all sorts of wounds, cuts and abrasions clean. With proper care, the disease can be prevented.


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  1. Nakamura S, Nakayama K, Mikami H, Imai T. Multiple necrotizing fasciitis: its etiology and histopathological features. The Journal of dermatology. Dec 1987;14(6):604-608.
  2. Galosi A, Luttiken R, Enderer K. [Etiology and diagnosis of necrotizing fasciitis (author's transl)]. Zeitschrift fur Hautkrankheiten. Jan 15 1981;56(2):118-125.
  3. Fink A, DeLuca G. Necrotizing fasciitis: pathophysiology and treatment. Medsurg nursing : official journal of the Academy of Medical-Surgical Nurses. Feb 2002;11(1):33-36.
  4. Young MH, Aronoff DM, Engleberg NC. Necrotizing fasciitis: pathogenesis and treatment. Expert review of anti-infective therapy. Apr 2005;3(2):279-294.
  5. McGee EJ. Necrotizing fasciitis: review of pathophysiology, diagnosis, and treatment. Critical care nursing quarterly. Jan-Mar 2005;28(1):80-84.
  6. Cawley MJ, Briggs M, Haith LR, Jr., et al. Intravenous immunoglobulin as adjunctive treatment for streptococcal toxic shock syndrome associated with necrotizing fasciitis: case report and review. Pharmacotherapy. Sep 1999;19(9):1094-1098.
  7. Novelli G, Catanzaro S, Canzi G, Sozzi D, Bozzetti A. Vacuum assisted closure therapy in the management of cervico-facial necrotizing fasciitis: a case report and review of the literature. Minerva stomatologica. Apr 2014;63(4):135-144.
  8. de Geus HR, van der Klooster JM. Vacuum-assisted closure in the treatment of large skin defects due to necrotizing fasciitis. Intensive care medicine. Apr 2005;31(4):601.
  9. Hirn M. Hyperbaric oxygen in the treatment of gas gangrene and perineal necrotizing fasciitis. A clinical and experimental study. The European journal of surgery. Supplement. : = Acta chirurgica. Supplement. 1993(570):1-36.
  10. Krasova Z, Matusek A, Chmelar D. [Hyperbaric oxygenation in the treatment of necrotizing fasciitis]. Vnitrni lekarstvi. Jul 1992;38(7):640-644.

Media References

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