Cellular Injury, Adaptations, Necrosis And Pathological Calcification

Question 1

Atrophy

Answer 1

Decrease in size of a tissue or organ due to a decrease in size of composite cells.
Physiologic can be before birth. Pathologic can include Alzheimers, muscular dystrophy etc.

Question 2

Development of pathologic atrophy

Answer 2

Reduced nutrition
Reduced blood supply 
Lack of innervation 
Lack of mechanical use
Reduced hormonal stimulation 
Pressure from other structures (eg tumours)
Aging 
Genetics

Question 3

Hyperplasia

Answer 3

Increase in size of a tissue or organ due to an increase in NUMBER of composite cells
Only occurs in cells that divide (cannot occur in neurones, cardiac muscle cells or skeletal muscles)
Physiologic: kidney regeneration, breast development etc
Pathologic: hyperplasia of prostate

Question 4

Metaplasia

Answer 4

The changing of one fully differentiated cell type into another. Cells change by adapting to their environment.
Pathologic example: squamous cell carcinoma

Question 5

Coagulative necrosis

Answer 5

Death of cells, dead tissue appears as a solid, pale yellow, coagulated mass.
Generally occurs to most solid organs: heart, liver, lung, spleen etc.

Question 6

Liquefactive necrosis

Answer 6

Neural tissue is the only tissue which liquifies.
Bacteria can also cause liquefaction necrosis of tissue and bacterial instigated liquefactive necrosis can occur in tissue that normally would undergo coagulative necrosis eg in the lungs.

Question 7

Caseous necrosis

Answer 7

Typically seen in TB and the dead tissue takes on a cottage cheese appearance and hence the name caseous

Question 8

Gangrenous necrosis

Answer 8

Superimposed bacterial infection on already dead tissue (usually as a result of Ischaemia) and presents with blackening of the tissue. Common in poorly treated diabetic individuals.

Question 9

Dystrophic pathological calcification

Answer 9

Most common type.
Occurs in tissues that have cell necrosis and lipid accumulation, as these are good attractors of calcium ions and subsequent calcification, which is mainly calcium phosphate mineral.
Results in stiffer arteries and subsequent issues, generally in elderly.
Mainly occurs in heart valves and arteries.

Question 10

Metastatic pathological calcification

Answer 10

Tissues calcify because the individual usually has chronic hypercalcaemia (high blood calcium levels).
Can occur in many areas such as arteries and heart valves, skin, skeletal muscle, ligaments etc.
people with renal disease, certain cancers or diseases of the parathyroid gland are most common recipients.

Question 11

Hypertrophy

Answer 11

Increase in size of a tissue or organ due to an increase in size of composite cells.
If enlargement results in dysfunction than it is pathologic.
Occurs in cells that do not divide (cardiac muscle and skeletal muscle) but can also occur in some smooth muscle and some epithelial cells.