cell injury and death (3) Flashcards
necrosis
cell death
most common cause of cell injury>
hypoxia
what is hypoxia?
low oxygen delivery to tissues resulting in low ATP production which disrupts key cellular function such as Na/K pump, Ca pump, aerobic respiration (lactic acid buildup)
most common cause of hypoxia
Ischemia
what is ischemia
low blood flow to an organ
arterial perfusion
atherosclerosis
venous drainage
(Budd-Chiari syndrome)
hypoxemia
low partial pressure of oxygen in blood
reversable injury: Generalized swelling of the cell
failure of energy-dependent-ion pumps- in CM.
It is usually the first manifestation.
plasma membrane alterations (reversable injury)
blebs, blunting or loss of villi.n
loosening of intercellular attachments.
nuclear alterations (reversable injury)
nuclear chromatin clumping
morphological features for irreversible injury (necrosis):
Loss of membrane integrity & Damage to nuclear material.
inflammatory response.
Karyolysis (nuclear changes in necrosis)
loss of DNA, fade of basophilia
pyknosis (nuclear changes in necrosis)
nuclear shrinkage and increased basophilia → Disappearance of the nucleus.
Karyorhexis: (nuclear changes in necrosis)
fragmentation of the pyknotic nucleus
coagulative necrosis (distinctive pattern)
preservation of the architecture of dead tissue
Eosinophilic anucleated cells.
Ischemia in any organ except the brain may lead to coagulative necrosis.
liquefactive necrosis (distinctive pattern)
Digestion of dead cells resulting into a liquid viscous mass.
In focal bacterial or fungal infections & in hypoxic death in CNS.
Creamy yellow: accumulation of dead leukocytes (pus).
Gangrenous necrosis (Not a distinctive pattern)
Used clinically in describing lower limb coagulative necrosis
secondary to ischemia.
