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DictionarySeegangreneFournier's gangrene
gangrene [gang´grēn] the death of body tissue, generally in considerable mass, usually associated with loss of vascular (nutritive) supply, and followed by bacterial invasion and putrefaction. Although it usually affects the extremities, gangrene sometimes may involve the internal organs. Symptoms depend on the site and include fever, pain, darkening of the skin, and an unpleasant odor. If the condition involves an internal organ, it is generally attended by pain and collapse. Treatment includes correcting the causes and is frequently successful with modern medications and surgery.Types of Gangrene. The three major types are moist, dry, and gas gangrene. Moist and dry gangrene result from loss of blood circulation due to various causes; gas gangrene occurs in wounds infected by anaerobic bacteria, among which are various species of Clostridium, which break down tissue by gas production and by toxins. Moist gangrene is caused by sudden stoppage of blood, resulting from burning by heat or acid, severe freezing, physical accident that destroys the tissue, a tourniquet that has been left on too long, or a clot or other embolism. At first, tissue affected by moist gangrene has the color of a bad bruise, is swollen, and often blistered. The gangrene is likely to spread with great speed. Toxins are formed in the affected tissues and absorbed. Dry gangrene occurs gradually and results from slow reduction of the blood flow in the arteries. There is no subsequent bacterial decomposition; the tissues become dry and shriveled. It occurs only in the extremities, and can occur with arteriosclerosis, in old age, or in advanced stages of diabetes mellitus. buerger's disease can also sometimes cause dry gangrene. Symptoms include gradual shrinking of the tissue, which becomes cold and lacking in pulse, and turns first brown and then black. Usually a line of demarcation is formed where the gangrene stops, owing to the fact that the tissue above this line continues to receive an adequate supply of blood. Gas gangrene results from dirty lacerated wounds infected by anaerobic bacteria, especially species of Clostridium. It is an acute, severe, painful condition in which muscles and subcutaneous tissues become filled with gas and a serosanguineous exudate.Internal Gangrene. In hernia" >strangulated hernia, a loop of intestine is caught in the bulge and its blood supply is cut off; gangrene may occur in that section of tissue. In acute appendicitis, areas of gangrene may occur in the walls of the appendix with consequent rupture through a gangrenous area. In severe cases of cholecystitis, which is usually associated with gallstones, gangrene may develop where the stones compress the mucous membrane. Thrombosis of the mesenteric artery may result in gangrene. Gangrene can be a rare complication of lung abscess in pneumonia; a symptom is brown sputum with a foul smell. Prevention. To prevent gangrene in an open wound, the wound should be kept as clean as possible. Special wound care is particularly important in patients with diabetes mellitus, malnutrition, and immunodeficiency. frostbite is especially dangerous, for the freezing impedes circulation, skin becomes tender and easily broken, and underlying cells are destroyed.Fournier's gangrene an acute gangrenous infection of the scrotum, penis, or perineum following local trauma, operative procedures, an underlying urinary tract disease, or a distant acute inflammatory process. Called also Fournier's disease.gas gangrene a condition often resulting from dirty, lacerated wounds in which the muscles and subcutaneous tissue become filled with gas and a serosanguineous exudate. It is due to species of Clostridium that break down tissue by gas production and by toxins. |