Cell Injury

Question 1

Types of Cellular Adaptation

Answer 1

Hypertrophy, Hyperplasia, Atrophy, Metaplasia

Question 2

Hypertrophy, hyperplasia. Caused by?

Answer 2

Increase in cell size, increase in cell number. Caused by increased functional demand, increased endocrine stimulation, increased nutrition

Question 3

Atrophy, caused by?

Answer 3

Decrease in size and function of a cell. Can be caused by physiologic functions like withdrawal of hormones, or pathologic, like decreased functional demand or starvation.

Question 4

Metaplasia, caused by?

Answer 4

Replacement of one type of differentiated tissue by another type of differentiated tissue. Caused by reprogramming of stem cells. For example, switch to stratified squamous epithelium.

Question 5

Lipofuscin

Answer 5

Wear and tear pigment. Accumulates from normal metabolism.

Question 6

Hemosiderin

Answer 6

In small amounts is innocuous, but can cause injury in high amounts. Comes from iron digestion by macrophages.

Question 7

Niemann-Pick Disease

Answer 7

Caused by failure to break down sphingomyelin.

Question 8

Alpha-1-Antitrypsin Deficiency

Answer 8

A1A is a protease inhibitor of elastase. Deficiency of A1A causes accumulation of misfolded proteins and cause ER stress.

Question 9

Hydropic change

Answer 9

A reversible form of injury where the cells swell due to damage.

Question 10

Increasing or decreasing in severity? Swelling of organelles, disaggregation of ribosomes, cytoplasmic blebs, calcium deposits in mitochondria, disrupted plasma membrane and organelles.

Answer 10

Increasing in severity!

Question 11

Ischemia

Answer 11

Decreased blood flow resulting in hypoxia and hypoglycemia

Question 12

Dystrophic Calcification vs Metastatic Calcification

Answer 12

Both irreversible!
Dystrophic occurs in injured tissues under normal calcium conditions. Can occur in heart valves, atherosclerotic blood vessels, neoplasms. Metastatic calcification occurs in healthy tissues as a result of increased serum calcium levels and abnormal calcium metabolism (hyperparathyroidism, renal failure).

Question 13

How does calcification appear histologically?

Answer 13

Fuzzy, deep purple in lumen.

Question 14

Coagulative Necrosis

Answer 14

Due to ischemic injury. Cells appear more eosinophilic.

Question 15

Pyknosis, Karyorrhexis, Karyolysis

Answer 15

Condensed, broken, missing nuclei. Classic necrosis signs.

Question 16

Liquefactive Necrosis

Answer 16

Usually caused by bacterial or fungal infections. All necrosis in brain. Structure breaks down with neutrophilic infiltrates.

Question 17

Caseous Necrosis

Answer 17

Usually following TB. Structure breakdown. Very pink

Question 18

Fat Necrosis

Answer 18

Due to release of digestive enzymes. Very blobby, calcification occurs.

Question 19

Fibrinoid Necrosis

Answer 19

Usually seen in injured blood vessels. Generally walled off and very collagenous.

Question 20

Apoptotic Cell Appearance

Answer 20

Cell membrane intact, appears very multinucleated.