Gas gangrene | |
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Photograph before right leg amputation (hemipelvectomy) of a patient with gas gangrene. The right thigh is edematous (swollen) and discoloured with necrotic bullae (large blisters). Crepitation is detected on deep palpation. At this juncture, the patient is in shock. | |
Classification and external resources | |
Specialty | Infectious disease |
ICD-10 | A48.0 |
ICD-9-CM | 040.0 |
DiseasesDB | 31141 |
MedlinePlus | 000620 |
eMedicine | article/217943 article/782709 article/214992 |
MeSH | D005738 |
Gas gangrene (also known as clostridial myonecrosis and myonecrosis) is a bacterial infection that produces gas in tissues in gangrene. This deadly form of gangrene usually is caused by Clostridium perfringens bacteria. It is a medical emergency. About 1000 cases of gas gangrene occur yearly in the United States.
Myonecrosis is a condition of necrotic damage, specific to muscle tissue. It is often seen in infections with C. perfringens or any of myriad soil-borne anaerobic bacteria. Bacteria cause myonecrosis by specific exotoxins. These microorganisms are opportunistic and, in general, enter the body through significant skin breakage. Gangrenous infection by soil-borne bacteria was common in the combat injuries of soldiers well into the 20th century, because of nonsterile field surgery and the basic nature of care for severe projectile wounds.
Other causes of myonecrosis include envenomation by snakes of the Bothrops genus (family Viperidae), ischemic necrosis, caused by vascular blockage (e.g., diabetes type II), tumours that block or hoard blood supply, and disseminated intravascular coagulation or other thromboses.
Gas gangrene can cause myonecrosis (muscle tissue death), gas production, and sepsis. Progression to toxemia and shock is often very rapid. It can easily be noticed by the large, blackened sores that form, as well as a degree of loud and distinctive crepitus caused by gas escaping the necrotic tissue.