Cell Injury

Question 1

What is hyperplasia?

Answer 1

Increase in the number of cells

Question 2

What is hypertrophy?

Answer 2

Increase in the size of cells

Question 3

What is atrophy?

Answer 3

Decrease in the size of cells

Question 4

What is metaplasia?

Answer 4

Substitution of a different adult cell type

Question 5

What is the first change with cell injury?

Answer 5

Cell function

Question 6

What is hypoxic cell injury?

Answer 6

Ischemia causes decreased mitochondrial output due to lack of O2 which leads to decreased ATP which lead to decreased Na/K Pump activity.

This leads to increased intracellular Ca2+, Na+ and H2O which causes cellular swelling.

Question 7

What is free radical injury?

Answer 7

Caused by free radicals such as ROS which come from cellular respiration can damage cells.

Question 8

What can reperfusion cause?

Answer 8

Reperfusion injury which is caused by free radical injury with the return of blood/O2 to ischemic tissue that leads to the production of free radicals

Question 9

What are some features of reversible cell injury?

Answer 9

1. Cellular swelling
2. Steatosis (fatty change)
3. Myelin figures
4. ER swelling
5. Membrane blebs

Question 10

What are the features of irreversible cell injury?

Answer 10

Cell death via necrosis or apoptosis

Question 11

What is the main difference between necrosis and apoptosis?

Answer 11

Necrosis is characterized by an inflammatory response which will recruit neutrophils.

Question 12

What is coagulation necrosis?

Answer 12

Associated with severe ischemia and is seen in the heart and kidney

Question 13

What is liquefactive necrosis?

Answer 13

Associated with bacterial infections and brain infarct/hypoxia.

Bacteria release enzymes causinga rapid loss of cellular structure and a collection of liquid, amorphous debris

Question 14

What is caseous necrosis?

Answer 14

Associated with inflammatory granulomas and the necrotic tissue is soft, white and friable.

Question 15

What is enzymatic fat necrosis?

Answer 15

Cell death in the pancreas leads to the release of lipases that digest lipids that mix with Ca into yellow soaps

Question 16

What is gangrene?

Answer 16

It represents coagulation (ischemic) necrosis, usually of an extremity, bowel or gallbladder

Question 17

Ischemic injury to the central nervous system from right internal carotid arterial occlusion suffered by a 72 year old man will result in what pattern of necrosis?

Answer 17

Liquefactive

Question 18

Which are the major mechanisms which result in membrane damage typical for a reperfusion injury following myocardial ischemia in a 68 year old woman?

Answer 18

Reactive O2 Species

Question 19

Scattered acidophilic bodies are found in the liver of a 57 year old man who has recently developed nausea, vomiting, and scleral icterus. His serologic test for viral hepatitis A is positive. What is the most likely pattern of tissue alteration?

Answer 19

Apoptosis

Question 20

An endocervical biopsy in a 23 year old woman demonstrates the presence of squamous epithelium. What process has occurred? Why?

Answer 20

Metaplasia

Question 21

What is karyolysis?

Answer 21

The basophilia of the chromatin may fade, a change that reflects loss of DNA because of enzymatic degradation by endonucleases.

Question 22

What is pyknosis?

Answer 22

Characterized by nuclear shrinkage and increased basophilia. The chromatin condenses into a solid, shrunken basophilic mass (also seen in apoptosis)

Question 23

What is karyorrhexis?

Answer 23

The pyknotic nucleus undergoes fragmentation. In a day or two, the nucleus in the necrotic cell totally disappears.

Question 24

What is a type of hyperplasia that is unrelated to cancer?

Answer 24

Benign Prostatic Hyperplasia