Gangrene is the term used by the clinician to describe local death of tissue (necrosis) occurring in the living body. Gangrene implies a fairly rapid process (developing in days) extending over a large visible area (a few to many centimeters) with an obvious inability of the tissues to repair or replace the gangrenous part. Although gangrene can occur in internal organs (e.g., large intestine), it generally refers to a process occurring on the surface of the body. It may involve only the skin, or it may extend into deeper tissues such as muscle or nerves.

Gangrene may be either dry or moist. Dry gangrene describes necrosis of the tissues of the extremities resulting from vascular occlusion, such as occurs in severe arteriosclerosis of the legs. Wet or moist gangrene occurs when bacteria invades dead tissue, producing putrefaction. When the gas-forming group of bacteria is involved, gas gangrene occurs. A gangrene may be dry at first, and be converted to the moist type by invading bacteria.

Clinical Manifestations

In dry gangrene, the arterial supply is gradually cut off and a drying or mummification of the tissues results. There is frequently an absence of inflammation, but pain of varying degree may precede the color changes. The soft tissue slowly and progressively shrinks and the color gradually deepens until the whole area is coal black. Constitutional symptoms may occur but are less severe than in moist gangrene.