Gas gangrene is a potentially deadly form of tissue death (gangrene).

See also: Necrotizing subcutaneous infection

Gas gangrene is rare in the U.S. The condition is most often caused by a bacteria called Clostridium perfringens. However, it also can be caused by Group A streptococcus. Staphylococcus aureus and Vibrio vulnificus can cause similar infections.

Under low-oxygen (anaerobic) conditions, Clostridium produces toxins that cause tissue death and related symptoms.

Gas gangrene generally occurs at the site of trauma or a recent surgical wound. The onset of gas gangrene is sudden and dramatic. About a third of cases occur on their own. Patients who develop this disease in this manner often have underlying blood vessel disease (atherosclerosis or hardening of the arteries), diabetes, or colon cancer.

Clostridium bacteria produce many different toxins, four of which (alpha, beta, epsilon, iota) can cause potentially deadly syndromes. The toxins cause damage to tissues, blood cells, and blood vessels.

The site of infection becomes inflamed with a pale-to-brownish-red and very painful tissue swelling. If you press on the swollen tissue with your fingers, you may feel gas as a crackly sensation. The edges of the infected area expand so quickly that changes are visible over a few minutes. The involved tissue is completely destroyed.

Symptoms include:

• Air under the skin (subcutaneous emphysema)
• Anxiety
• Blisters filled with brown-red fluid
• Drainage from the tissues, foul-smelling brown-red or bloody fluid (serosanguineous discharge)
• Increased heart rate (tachycardia)
• Moderate-to-high fever
• Moderate-to-severe pain around a skin injury
• Pale skin color, later becoming dusky and changing to dark red or purple
• Progressive swelling around a skin injury
• Sweating
• Vesicle formation, combining into large blisters
• Yellow color to the skin (jaundice)

Note: Symptoms usually begin suddenly and quickly worsen.

If the condition is not treated, the person can develop a shock-like syndrome with decreased blood pressure (hypotension), kidney failure, coma, and finally death.

The person may be in shock. A health care professional might feel air in the tissues (crepitus).

• Anaerobic tissue and/or fluid culture may reveal Clostridium species
• Blood culture may grow the bacteria causing the infection
• Gram stain of fluid from the infected area may show gram-positive rods (Clostridium species) or other bacterial types
• X-ray, CT scan, or MRI of the area may show gas in the tissues