fat necrosis

necrosis /ne·cro·sis/ (nĕ-kro´sis) pl. necro´ses   [Gr.] the morphological changes indicative of cell death caused by progressive enzymatic degradation; it may affect groups of cells or part of a structure or an organ.

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aseptic necrosis  necrosis without infection, usually in the head of the femur after traumatic hip dislocation.

Balser's fatty necrosis  gangrenous pancreatitis with omental bursitis and disseminated patches of necrosis of fatty tissues.

caseous necrosis  cheesy n.

central necrosis  that affecting the central portion of an affected bone, cell, or lobule of the liver.

cheesy necrosis  that in which the tissue is soft, dry, and cottage cheese–like; most often seen in tuberculosis and syphilis.

coagulation necrosis  necrosis of a portion of some organ or tissue, with formation of fibrous infarcts, the protoplasm of the cells becoming fixed and opaque by coagulation of the protein elements, the cellular outline persisting for a long time.

colliquative necrosis  that in which the necrotic material becomes softened and liquefied.

contraction band necrosis  a cardiac lesion characterized by hypercontracted myofibrils and contraction bands and mitochondrial damage, caused by calcium influx into dying cells resulting in arrest of the cells in the contracted state.

fat necrosis  that in which the neutral fats in adipose tissue are split into fatty acids and glycerol, usually affecting the pancreas and peripancreatic fat in acute hemorrhagic pancreatitis.

liquefaction necrosis  colliquative n.

phosphorus necrosis  necrosis of the jaw bone due to exposure to phosphorus.

postpartum pituitary necrosis  necrosis of the pituitary during the postpartum period, often associated with shock and excessive uterine bleeding during delivery, and leading to variable patterns of hypopituitarism.

subcutaneous fat necrosis  induration of the subcutaneous fat in newborn and young infants.

necrosis ustilagi´nea  dry gangrene due to ergotism.

Zenker's necrosis  see under degeneration.

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fat necrosis

n.

Necrosis of adipose tissue, characterized by the formation of small quantities of calcium soaps when fat is hydrolyzed into glycerol and fatty acids. Also called steatonecrosis.

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fat necrosis

Etymology: AS, faett + Gk, nekros, dead, osis, condition

a condition caused by trauma or infection in which neutral tissue fats are broken down into fatty acids and glycerol. Fat necrosis occurs most commonly in the breasts and subcutaneous areas. It also may develop in the abdominal cavity after an episode of pancreatitis causes a release of enzymes from the pancreas.

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necrosis [nĕ-kro´sis, ne-kro´sis] (Gr.)

the morphological changes indicative of cell death caused by enzymatic degradation.

aseptic necrosis necrosis without infection or inflammation.

acute tubular necrosis acute renal failure with mild to severe damage or necrosis of tubule cells, usually secondary to either nephrotoxicity, ischemia after major surgery, trauma (see crush syndrome), severe hypovolemia, sepsis, or burns. See also lower nephron nephrosis.

Balser's fatty necrosis gangrenous pancreatitis with omental bursitis and disseminated patches of necrosis of fatty tissues.

bridging necrosis septa of confluent necrosis bridging adjacent central veins of hepatic lobules and portal triads characteristic of subacute hepatic necrosis.

caseous necrosis caseation (def. 2).

central necrosis necrosis affecting the central portion of an affected bone, cell, or lobule of the liver.

cheesy necrosis caseation (def. 2).

coagulation necrosis death of cells, the protoplasm of the cells becoming fixed and opaque by coagulation of the protein elements, the cellular outline persisting for a long time.

colliquative necrosis liquefactive necrosis.

fat necrosis necrosis in which fat is broken down into fatty acids and glycerol, usually occurring in subcutaneous tissue as a result of trauma.

liquefactive necrosis necrosis in which the necrotic material becomes softened and liquefied.

massive hepatic necrosis massive, usually fatal, necrosis of the liver, a rare complication of viral hepatitis (fulminant hepatitis) that may also result from exposure to hepatotoxins or from drug hypersensitivity.

moist necrosis necrosis in which the dead tissue is wet and soft.

postpartum pituitary necrosis see postpartum pituitary necrosis.

selective myocardial cell necrosis myofibrillar degeneration.

subcutaneous fat necrosis of newborn a benign, self-limited disease affecting term newborns and young infants, characterized by circumscribed, indurated, nodular areas of fat necrosis. It is thought to be related to trauma on bony prominences during delivery, hypothermia, asphyxia, or maternal diabetes; it usually resolves spontaneously by 2 to 4 weeks with no scarring. Called also adiponecrosis neonatorum or subcutanea.

Zenker's necrosis hyaline degeneration and necrosis of striated muscle; called also Zenker's degeneration.

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fat

1. the adipose or fatty tissue of the body.

2. neutral fat; a triglyceride (or triacylglycerol), which is an ester of fatty acids and glycerol (a trihydric alcohol). Each fat molecule contains one glycerol residue connected by ester linkages to three fatty acid residues, which may be the same or different. The fatty acids may have no double bonds in the carbon chain (saturated fatty acids), one double bond (monounsaturated), or two or more double bonds (polyunsaturated).

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fat absorption test

assesses the absorptive capacity of the small intestine, quantitatively by measuring serum lipid levels or qualitatively by plasma turbidity, at timed intervals after the oral administration of fats.

animal fat

a most important abattoir by-product providing edible fat for the human food chain. Products include oleo oil and oleo stearin used in margarine manufacture and dripping for commercial baking. Nonedible fats go to leather dressings, glycerol manufacture and lubricants. Beef and pork fat are the valuable ones, mutton fat having too strong a flavor for edible fat.

boiling (burning) fat

see acrolein poisoning.

fat cattle

a class of beef cattle of any age but usually greater than one year, well-covered and judged ready for slaughter to provide prime cuts of beef.

fat cow syndrome

a syndrome of anorexia and ketonuria that occurs in overfat cows at calving. Precipitated by events that interfere with the cow's feed intake for even short periods. A poor response to treatment and many cows die.

Fatty liver in fat cow syndrome. By permission from Blowey RW, Weaver AD, Diseases and Disorders of Cattle, Mosby, 1997

crude fat

that part of a feed that is extractable by ether. Includes fat, oil, wax, resin and some pigments.

dietary fat

a rich source of energy for carnivores and omnivores and to a limited extent ruminants. Are usually too expensive for widespread use other than as excipients. They aid in the formation of pellets and in reducing dustiness. Their problem is a tendency to rancidification unless an antioxidant is added.

fat embolism

lesion created by a fat embolus.

fat embolus

globules of fat, sufficient to act as emboli occur usually after trauma or surgery, but can also occur in hyperlipemia, myositis and atherosclerosis.

fat ewe pregnancy toxemia

occurs when there is a voluntary restriction of food intake in late pregnancy associated with lack of ruminal expansion potential caused by excess abdominal fat and multiple fetuses. It is common in hobby sheep farms where it is thought that ewes should lamb with body condition scores greater than 4 rather than less than 3.5.

leaf fat

the best edible fat from a pig carcass, from under the peritoneum.

fat marbling

deposition of fat between muscle fibers. A highly desirable characteristic in beef. Is a guarantee of a carcass from a young animal.

fat necrosis

necrosis in which fat is broken down into fatty acids and glycerol, usually occurring in subcutaneous tissue as a result of trauma. See also lipomatosis.

orbital fat

fat located deep to the eyeball; substantial amounts provide good shock-absorbent surroundings.

perivaginal fat prolapse

during a difficult parturition in a fat cow or heifer perivaginal fat is pushed caudally and bursts through the vaginal wall into the vagina.

fat phanaerosis

conversion in the tissues of invisible fatty substances into fat which can be stained and thus become visible.

fat prolapse

see perivaginal fat prolapse (above).

fat sheep

a class of meat sheep of any age but usually greater than one year, well-covered and judged ready for slaughter to provide prime cuts of mutton.

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fat necrosis

Liquefactive necrosis initiated by trauma and effected by lipolytic enzymes. See Calcium soap, Necrosis.