What necrosis looks like?

Necrotizing soft tissue infection

Necrotizing soft tissue infection is a rare but very severe type of bacterial infection. It can destroy the muscles, skin, and underlying tissue. The word «necrotizing» refers to something that causes body tissue to die.

Causes

Many different types of bacteria can cause this infection. A very severe and usually deadly form of necrotizing soft tissue infection is due to the bacteria Streptococcus pyogenes, which is sometimes called «flesh-eating bacteria» or strep.

Necrotizing soft tissue infection develops when the bacteria enters the body, usually through a minor cut or scrape. The bacteria begin to grow and release harmful substances (toxins) that kill tissue and affect blood flow to the area. With flesh-eating strep, the bacteria also make chemicals that block the body’s ability to respond to the organism. As the tissue dies, the bacteria enters the blood and rapidly spreads throughout the body.

Symptoms

Symptoms may include:

• Small, red, painful lump or bump on the skin that spreads
• A very painful bruise-like area then develops and grows rapidly, sometimes in less than an hour
• The center becomes dark and dusky and then turns black and the tissue dies
• The skin may break open and ooze fluid

Other symptoms may include:

• Feeling ill
• Fever
• Sweating
• Chills
• Nausea
• Dizziness
• Weakness
• Shock

Exams and Tests

The health care provider may be able to diagnose this condition by looking at your skin. Or, the condition may be diagnosed in an operating room by a surgeon.

Tests that may be done include:

• Ultrasound
• X-ray or CT scan
• Blood tests
• Blood culture to check for bacteria
• An incision of the skin to see if pus is present
• Skin tissue biopsy and culture

Treatment

Treatment is needed right away to prevent death. You’ll likely need to stay in the hospital. Treatment includes:

• Powerful antibiotics are given through a vein (IV)
• Surgery to drain the sore and remove dead tissue
• Special medicines called donor immunoglobulins (antibodies) to help fight the infection in some cases

Other treatments may include:

• Skin grafts after the infection goes away to help your skin heal and look better
• Amputation if the disease spreads through an arm or leg
• Hundred percent oxygen at high pressure (hyperbaric oxygen therapy) for certain types of bacterial infections

Outlook (Prognosis)

How well you do depends on:

• Your overall health (especially if you have diabetes)
• How fast you were diagnosed and how quickly you received treatment
• The type of bacteria causing the infection
• How quickly the infection spreads
• How well treatment works

This disease commonly causes scarring and skin deformity.

Death can occur rapidly without proper treatment.

Possible Complications

Complications that may result from this condition include:

• Infection spreads throughout body, causing a blood infection (sepsis), which can be deadly
• Scarring and disfigurement
• Loss of your ability to use an arm or leg
• Death

When to Contact a Medical Professional

This disorder is severe and may be life threatening. Contact your provider right away if symptoms of infection occur around a skin injury, including:

• Drainage of pus or blood
• Fever
• Pain
• Redness
• Swelling

Prevention

Always clean the skin thoroughly after a cut, scrape, or other skin injury.

Alternative Names

Necrotizing fasciitis; Fasciitis — necrotizing; Flesh-eating bacteria; Soft tissue gangrene; Gangrene — soft tissue

References

Abbas M, Uçkay I, Ferry T, Hakko E, Pittet D. Severe soft-tissue infections. In: Bersten AD, Handy JM, eds. Oh’s Intensive Care Manual. 8th ed. Philadelphia, PA: Elsevier; 2019:chap 72.

Fitzpatrick JE, High WA, Kyle WL. Necrotic and ulcerative skin disorders. In: Fitzpatrick JE, High WA, Kyle WL, eds. Urgent Care Dermatology: Symptom-Based Diagnosis. Philadelphia, PA: Elsevier; 2018:chap 14.

Pasternack MS, Swartz MN. Cellulitis, necrotizing fasciitis, and subcutaneous tissue infections. In: Bennett JE, Dolin R, Blaser MJ, eds. Mandell, Douglas, and Bennett’s Principles and Practice of Infectious Diseases. 9th ed. Philadelphia, PA: Elsevier; 2020:chap 93.

Review Date 12/14/2021

Updated by: Ramin Fathi, MD, FAAD, Director, Phoenix Surgical Dermatology Group, Phoenix, AZ. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.

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Necrotising fasciitis

Symptoms of necrotising fasciitis can develop quickly within hours or over a few days.

At first you may have:

• intense pain or loss of feeling near to a cut or wound – the pain may seem much worse than you would usually expect from a cut or wound
• swelling of the skin around the affected area
• flu-like symptoms, such as a high temperature, headache and tiredness

Later symptoms can include:

• being sick (vomiting) and diarrhoea
• confusion
• black, purple or grey blotches and blisters on the skin (these may be less obvious on black or brown skin)

Information:

Necrotising fasciitis is very rare. The symptoms are similar to more common skin infections like cellulitis.

Immediate action required: Call 999 or go to A&E if:

• you have a cut or wound that is much more painful than you would expect,
• you have a cut or wound and get symptoms like a high temperature, headache, tiredness and muscle aches
• you have sudden confusion
• you have black, purple or grey blotches or blisters near a cut or wound

Important: Help from NHS 111

If you are not sure what to do, call 111 or get help from 111 online.

NHS 111 can tell you the right place to get help.

Treatments for necrotising fasciitis

Necrotising fasciitis gets worse quickly and can be fatal. It must be treated in hospital as soon as possible.

Treatment will usually include:

• antibiotics
• surgery to remove the affected area

Even after successful treatment, there may be long-term changes in how your body looks and how you move or use the affected part of your body. Sometimes amputation of affected limbs is needed.

You may need further surgery and physiotherapy to help you recover.

Causes of necrotising fasciitis

Necrotising fasciitis is an infection that can happen after getting a wound. It causes damage to the deep layers of your skin.

The infection may get into the body through:

• cuts and scratches
• burns and scalds
• insect bites
• surgery
• injecting drugs

You may be more at risk from developing necrotising fasciitis if you have diabetes or a weakened immune system.

Page last reviewed: 20 June 2022
Next review due: 20 June 2025

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necrosis

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necrosis
Related Topics: gangrene lung infarction lesion osteonecrosis infarction . (Show more)

necrosis, death of a circumscribed area of plant or animal tissue as a result of disease or injury. Necrosis is a form of premature tissue death, as opposed to the spontaneous natural death or wearing out of tissue, which is known as necrobiosis. Necrosis is further distinguished from apoptosis, or programmed cell death, which is internally regulated by cells, plays a critical role in embryonic development, and serves as a protective mechanism against disease and other factors.

Necrosis may follow a wide variety of injuries, both physical and biological in nature. Examples of physical injuries include cuts, burns, bruises, oxygen deprivation (anoxia), and hyperthermia. Biological injuries can include immunological attack and the effects of disease-causing agents. Notable conditions involving necrotic tissue death include avascular necrosis and gangrene, which result from a lack of blood supply to the affected area; necrotizing fasciitis, which is caused by a rapidly spreading bacterial infection; and loxoscelism, in which venom in a bite from a recluse spider (Loxosceles) produces a gangrenous wound. Such injuries and diseases inhibit crucial intracellular metabolic processes, in which intracellular enzymes become activated upon injury and destroy damaged cells. Lesions caused by necrosis often are of diagnostic value.

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Early cellular signs of necrosis include swelling of the mitochondria, a process that impairs intracellular oxidative metabolism. Later, localized densities appear, with condensation of genetic material. Cytoplasmic organelles are disrupted, and affected cells separate from neighbouring cells. The dissolution of lysosomes, which normally house hydrolytic enzymes, leads to intracellular acidosis. The nucleus swells and darkens (pyknosis) and eventually ruptures (karyolysis). The outer membrane of the cell also ruptures, resulting in a loss of ion-pumping capacity and a rapid flow of sodium and calcium ions into the intracellular environment, resulting in osmotic shock (a sudden shift in intracellular and extracellular solute concentrations).

This article was most recently revised and updated by Kara Rogers.