necrosis

Question 1

necrotic cells

Answer 1

increased eosinophilia in H and E staining. loss of cytoplasmic RNA (binds H). denatured cytoplasmic proteins (binds E)

glassy homogeneous appearance (loss of glycogen)

digestion of cytoplasmic organelles (vacuolated cytoplasm (moth eaten)

Question 2

dead cells

Answer 2

replaced by large, whorled phospholipid masses

Question 3

nuclear changes of necrotic cells

Answer 3

non-specific breakdown of DNA

karyolysis- fading of chromatin basophilia, loss of DNA endonucleases

pyknosis-nuclear shrinkage, increased basophilia, chromatin condensed into solid, shrunken mass

karyorrhexis-pyknotic nucleus fragments, nucleus disappears

Question 4

coagulative necrosis

Answer 4

architecture of dead tissues

displays firm texture

eosinophilic, anucleated cells persist for days or weeks.
removed by phagocytosis of the cellular debris by infiltrating leukocytes.
digestion if the dead cells by the action of lysosomal enzymes of the leukocytes

ischemia caused by obstruction in a vessel may lead to coagulative necrosis of the supplied tissue

Question 5

liquefactive necrosis

Answer 5

characterized by digestion of the dead cells (turns tissue into liquid viscous mass)

seen in focal bacterial infections

occasionally seen in fungals infections

creamy yellow (dead leukocytes, purulent matter)

hypoxic death of cells in the CNS

Question 6

gangrenous necrosis

Answer 6

not specific pattern of cell death

commonly used in clinical practice

applied to a limb (lost its blood supply and has undergone necrosis kind of coagulative)

add in a bacterial infection (more liquefactive, wet gangrene)

Question 7

caseous necrosis

Answer 7

encountered most often in foci of tuberculous infection

cheese-like-friable white appearance of the area of necrosis

microscopic examination (collection of fragmented or lysed cells, amorphous granular debris enclosed with a distinctive inflammatory border)

TB

Question 8

fat necrosis

Answer 8

does not denote a specific pattern of necrosis

focal areas of fat destruction-released of activated pancreatic lipases into the substance of the pancreas and the peritoneal cavity

Question 9

fibrinoid necorsis

Answer 9

special form of necrosis

seen in immune reactions involving blood vessels

complexes of Ag and Ab