Gangrene is the death and subsequent decay of body tissues caused by infection. It is most commonly the result of critically insufficient blood supply sometimes caused by an injury and subsequent contamination of the wound with bacteria. This condition is most common in the extremities.
One specific example of gangrene is so called diabetic foot that can be seen in long-standing complicated diabetes. It is caused by a combination of arterial ischemia, injury and poor healing that is rather common in diabetics.
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