Overview
Also known as myonecrosis, gas gangrene describes a bacterial infection of muscle tissue from adjacent traumatised tissues, originating in a wound contaminated with Clostridium perfringens. It is rapidly progressive (over hours) and can be life-threatening.
Pathophysiology
Gas gangrene is usually due to muscle injury and contamination. Clostridium perfringens can produce an alpha toxin, which is a lecithinase (a phospholipase), which is capable of breaking cell membranes causing muscle necrosis and haemolysis. It can also cause connective tissue breakdown, resulting in the rapid spread of infection to surrounding tissues and deeper into the muscles.
Presentation
Overview
Features of gas gangrene can progressive over hours and include:
- Acute, severe pain and tenderness in the affected area
- Shock – fever, tachycardia, and hypertension
- Necrosis and black, bubble-like lesions of the skin with foul-smelling discharge
- Crepitus may be felt when pressing on the swollen area
- In some people, oedema and tenderness may be the only signs
Diagnosis
Overview
The diagnosis is usually clinical, however, wound aspirate cultures can confirm the presence of Clostridium perfringens. X-rays may show gas in the affected tissues.
Management
Overview
Initial management involves urgent surgical debridement and intravenous empirical antibiotics (e.g. piperacillin-tazobactam).
Prognosis
- Mortality rates can be as high as 25%
