Wk 2 Path Lab Flashcards
4 common causes of cellular injury
- inflammation
- nutritional deficiency or excess
- hypoxia
- trauma
- genetic mutation
3 causes of hypoxia
- ischemia
- hypoxemia
- decreased O2-carrying capacity of blood
4.
What is the consequence of decreased oxygen?
Impaired oxidative phosphorylation -> decreased ATP production
Lack of ATP -> cellular injury
4 causes of hypoxemia
- high altitude
- hypoventilation
- diffusion defect
- V/Q mismastch
What is the hallmark of reversible injury?
cellular swelling
What does cellular swelling lead to?
loss of microvilli
membrane blebbing
swelling of RER
What is the hallmark of irreversible injury?
Cellular membrane damage
What 3 membranes can be damaged to -> irreversible damage?
- cell membrane
- mitochondrial membrane
- lysosome membrane
What 2 things does plasma membrane damage result in?
- cytosolic enzymes leaking into the serum (cardiac troponin)
- additional calcium entering the cell
What does mitochondrial membrane damage lead to?
- loss of electron transport chain (inner mito membrane)
- Cytochrome C leaking into cytosol (activates apoptosis)
What is the end result of irreversible injury?
cell death
What is the morphologic hallmark of cell death?
Loss of nucleus
How does loss of cell death occur?
- pyknosis (= nuclear condensation)
- karyorrhexis (=fragmentation)
- karyolysis (=dissolution)
What is necrosis?
= death of a large group of cells followed by acute inflammation
-divided into types based on gross features
6 types of necrosis
- coagulative necrosis
- liquefactive necrosis
- gangrenous necrosis
- caseous
- fat
- fibrinoid
6 types of necrosis
- coagulative necrosis
- liquefactive necrosis
- gangrenous necrosis
- caseous
- fat
- fibrinoid
What is coagulative necrosis?
- tissue remains firm
- cell shape and organ structure preserved
- nucleus disappears
- characteristic of ischemic infarction of any organ except the brain
Which one is necrosis and what is it of?
L is necrosis - no nuclei in glomerulus or tubules
-often pale and wedge-shaped, pointing toward area of occlusion