Gas gangrene
Alternative names:
tissue infection - clostridial; gangrene - gas; clostridial
myonecrosis; clostridial infection of tissues
Definition:
A severe form of gangrene (tissue death) caused by Clostridium
perfringes (see also necrotizing
subcutaneous infection).
Causes, incidence, and risk factors:
Gas gangrene occurs as a result of infection by Clostridium
bacteria that, under anaerobic
(low oxygen) conditions, produce toxins
that cause the tissue death and associated symptoms. Gas gangrene
is rare, with only 1,000 to 3,000 cases occurring in the United
States annually.
Gas gangrene generally occurs at the site of trauma or a recent
surgical wound. About
a third of cases occur spontaneously. Patients who develop
this disease spontaneously often have underlying vascular
disease (atherosclerosis or hardening of the arteries), diabetes,
or colon cancer. The onset of gas gangrene is sudden and dramatic.
Inflammation begins at the site of infection as pale
to brownish-red extremely painful tissue swelling.
Gas may be felt in the tissue as a crackly sensation when
the swollen area is pressed with the fingers. The margins
of the infected area expand so rapidly that changes are visible
over a few minutes of time. The involved tissue is completely
destroyed.
Clostridium bacteria produce many different toxins, four of
which (alpha, beta, epsilon, iota) can cause potentially fatal
syndromes. In addition they cause tissue death (necrosis),
destruction of blood (hemolysis),
local decrease in circulation (vasoconstriction),
and leaking on the blood vessels (increased vascular permeability).
These toxins are responsible for both the local tissue destruction
and the systemic symptoms
(the other symptoms throughout the body).
Systemic symptoms develop early in the infection. These consist
of sweating, fever,
and anxiety. If untreated
the individual develops a shock
- like syndrome with decreased blood
pressure (hypotension),
renal failure, coma,
and finally death.
Update Date: 02/09/00
Updated by: J. Gordon Lambert, MD, Associate Medical Director,
Utah Health Informatics and adam.com
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