6.10 Intro to Pathology Necrosis, Apoptosis

Question 1

What is Necrosis?

Answer 1

The death of cells or groups of cells within a living organism.

Question 2

What is the difference between Necrosis and Autolysis?

Answer 2

Necrosis is seen in the living (with inflammation) and autolysis is seen in tissues after death.

Question 3

Define coagulative necrosis

Answer 3

• The most common form of necrosis.
• Occurs when cell proteins are altered or denatured, similar to coagulation that occurs when cooking eggs. histologically, the cell outline are preserved ad the cytoplasm appears finely granular.

Question 4

What type of organ does coagulative necrosis normally occur in?

Answer 4

Solid internal organs.

Question 5

What is the best example of coagulative necrosis?

Answer 5

Heart tissue undergoing myocardial infarction.

Question 6

What is the hallmark cell of inflammation?

Answer 6

The neutrophils are always involved in necrosis, no neutrophil it is autolysis.

Question 7

What is liquefactive necrosis?

Answer 7

Referes to a process by which dead cells liquefy under the influence of certain cell enzymes. The tissue becomes soft and gel-like.

Question 8

What is the best and second best example of liquefactive necrosis?

Answer 8

1) brain infarcts

2) Abscesses in the lung/

Question 9

What is caseous necrosis?

Answer 9

A form of coagulative necrosis which a thick, yellowish, cheesy substance forms.

Question 10

What is the best example of caseous necrosis?

Answer 10

TB forms lung granulomas, which inside can be found caseous necrosis, this is called a Ghon Complex.

Question 11

What is the second best example of caseous necrosis?

Answer 11

Valley fever fungus.

Question 12

What is Fat necrosis?

Answer 12

A specialized form of liquefaction necrosis caused by the action of lipolytic enzymes.

Question 13

What is the best example of Fat necrosis?

Answer 13

Is limited to fat tissue, usually around the pancreas, where enzymes are released into the adjacent fat tissue, usually after rupture of the pancreas, causing degradation of fat into glycerol and free fatty acids. The free fatty acids rapidly bind with calcium form in saps, and causing whit calcified specks.

Question 14

What is the difference between Coagulative and liquefactive Necrosis?

Answer 14

Liquefactive turns to liquid, where as coagulative turns more solid jelly like.

Question 15

What is the difference between Liquefactive and fat necrosis?

Answer 15

Fat necrosis is a type of liquefaction necrosis, but can only occur in fat tissue.

Question 16

What is the difference between Wet and Dry Gangrene?

Answer 16

Necrotic tissue can provide a good medium for infection by bacteria. The bacterial infection of coagulated tissue leads to inflammation and secondary liquefaction clinically known as wet gangrene. If the necrotic tissue dries out, it becomes black and mummified or dry gangrene. Such infections frequently occur after an infarction of the intestine or in a limb and are usually caused by atherosclerosis or diabetes.

Question 17

What is a Dystrophic Calcification?

Answer 17

Necrotic tissue attracts calcium salts and frequently undergoes calcification. Refers ti the macroscopic deposition of calcium in injured or dead tissues. Represents an extracellular deposition of calcium from the circulation into dead or ting necrotic tissue often visible to the naked eye, and range from gritty, sand-like grains to firm, rock hard material.

Question 18

What is metastatic calcification?

Answer 18

Reflects deranged calcium metabolism (not cell injury), usually associated with increased serum calcium levels, leading to deposition of calcium in other locations.

Question 19

Examples of Dystrophic Calcifications

Answer 19

1) Calcifications in Atherosclerotic Cornary arteries
2) Calcifications of the Mitral or Aortic valves
3) Calcifications seen around breast cancer
4) Infant periventricular calcifications seen in congenital Toxoplasmosis

Question 20

Example of Metastatic calcifications

Answer 20

Seen in various disorder including Hyperparathryroidism, Vitamin D toxicity, and Chronic Renal Failure, can also be seen in formations of Calcium Carbonate stones in sties such as the gallbladder, kidney, and bladder are due to precipitation of the salts from solution into tissues.

Question 21

Define Apoptosis

Answer 21

Is a form of programed cell death (no inflammation) that is an energy dependent process designed to switch cells off and eliminate them. It is usually a physiological process occurring normally during development, but can be caused by radiation, chemotherapeutic drugs, or tumors causing the death of normal cells.

Question 22

Where is the most common place for apoptosis to occur?

Answer 22

The brain

Question 23

How are apoptotic cells identified?

Answer 23

• Apoptotic cells are recognized by nuclear fragmentation and pyknosis of individual cells or small groups of cells.
• Inflammation and necrosis are generally not present.
• Appear shrunken with round or oval masses of bright pink or orang in the cytoplasm (apoptotic bodies), cytoplasmic blebs, and nuclear fragments.