Lecture 57 - Gen Path Cell Injury Flashcards
What is reversible cell injury defined as
altered state which will revert to normal upon the removal of the stimulus
What are two categories of Hallmark changes in reversible cell injury
- cell swelling
- clumped chromatin
cell swelling is caused by
altered sodium-potassium ion concentration which cause water influx
clumped chromatin is caused by
low oxygen environments that decrease cellular pH
What is another term for cell swelling
hydropic degeneration
On histology, how is cell swelling illustrated?
pallor without inflammation
T/F: fatty change is a reversible cell injury
TRUE
what is fatty change
accumulation of triglycerides in organs
what is the gross anatomy of fatty change
enlarged, pale, greasy
what are microscopic changes of fatty change
discrete, clear cytoplasmic vacuoles
What is considered irreversible cell injury? what are examples?
anything resulting in cell death
- necrosis
- apoptosis
what are the hallmark changes of irreversible cell death
- pyknosis (condensed chromatin)
- karyorrhexis (nuclear fragmentation)
- karyolysis (nuclear dissolution)
- hypereosinophilia
T/F: inflammation is a feature of reversible cell injury
FALSE
what two changes are specific to necrosis
- mineralization (calcium influx)
- inflammation
what are the types of necrosis
- Coagulative
- Lytic/Liquefactive
- Caseous
- Fat
- Gangrenous
Describe coagulative necrosis
- pallor +/- hemorrhagic ring
- hypereosinophilia
- cellular outlines
Describe Zenker’s necrosis (include common causes)
- coagulative specific to skeletal mm.
- Vitamin E/Se deficiency (white mm. disease)
- capture myopathy
- compartment syndrome
Describe Lytic/Liquefactive necrosis
- neutrophilic breakdown of tissue
- cellular debris
- pale, softened tissue
Describe liquefactive necrosis in the CNS (-malacia)
- macrophages play role
- cavitation
- ischemia or vascular event
Describe caseous necrosis
- white, soft, friable
- granulomas present
- common in heterophils and mycobacterium
Describe fat necrosis
- acute inflammation near/within adipose
- white, chalky calcium soaps
- basophilia
Describe gangrenous necrosis
- necrosis of extremities
- black skin (dry)
- w/ putrefaction (wet)
- vascular disruption
what are the physiologic causes of apoptosis
- immune surveillance (self-reactive T cells die in the thymus)
- Hormonal involution
- Embryologic reduction in cells
what are the pathologic causes of apoptosis
- atrophy
- cell death in tumors/virus-mediated
- DNA damage
- accumulation of misfolded proteins
what are the two pathways of apoptosis are there
- intrinsic (mitochondrial)
- extrinsic (death receptor-initiated)
what changes are seen with apoptosis
- cell shrinkage
- hypereosinophilia
- chromatin clumping
- no inflammation
- reduction in organ/tissue size
what adaptations are reversible
- hypertrophy
- hyperplasia
- metaplasia
Hypertrophy
increased cell size
in striated/smooth mm.
Hyperplasia
increased cell number
readily dividable tissues
normal or excessive hormone stimulation
Metaplasia
one cell type converts to another
chronic irritation or hormonal factors
atrophy
decrease in cell size or number
hypoplasia
failure of tissue/organ to reach mature/adult size
distinguish by age and microscopic changes
