Necrosis vs Gangrene: What's the Difference Quiz and Flashcards

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What is the consequence of severe injury?

Inflammation

A pathologic process (correct)

Hypertrophy

Apoptosis

Which type of necrosis is most commonly seen in hypoxic death of all tissues except the brain?

Coagulative necrosis (correct)

Liquefactive necrosis

Fat necrosis

Caseous necrosis

What is the characteristic of affected cells in coagulative necrosis?

Eosinophilic, granular mass with fragmented nucleus

Neutrophilic, vacuolated mass with intact nucleus

Basophilic, transparent mass with presence of nucleus

Acidophilic, opaque mass with loss of nucleus (correct)

What is the result of microbial stimulation in liquefactive necrosis?

Accumulation of leucocytes and liberation of enzymes Signup and view all the answers

What is the gross morphology of affected area in liquefactive necrosis?

Affected area is soft, liquid, viscous mass Signup and view all the answers

What is the difference between coagulative necrosis and liquefactive necrosis?

Coagulative necrosis affects all tissues except brain, while liquefactive necrosis affects brain tissue Signup and view all the answers

What is the appearance of the affected area in caseous necrosis?

Soft, friable white cheesy material Signup and view all the answers

What is the cause of fat necrosis in acute haemorrhagic pancreatitis?

Release of activated pancreatic lipases Signup and view all the answers

What type of necrosis is characterized by complete destruction of cells and is amorphous acidophilic fluid?

Gangrenous necrosis Signup and view all the answers

What is the result of the combination of fatty acids with calcium in fat necrosis?

Visible chalky white areas Signup and view all the answers

What is the predominant type of necrosis in dry gangrene?

Coagulative necrosis Signup and view all the answers

What is the cause of liquefactive necrosis in gangrenous necrosis?

Bacteria and the attracted leucocytes Signup and view all the answers

What is the characteristic histological feature of fibrinoid necrosis?

Bright pink and amorphous appearances in H&E stains Signup and view all the answers

What is the primary cause of dry gangrene?

Arterial occlusion Signup and view all the answers

What is the characteristic difference in the distribution of dry and wet gangrene?

Dry gangrene affects only limbs, while wet gangrene affects limbs and bowel Signup and view all the answers

What is the characteristic gross appearance of wet gangrene?

Moist, soft, and swollen Signup and view all the answers

What is the primary difference in the presence of bacteria between dry and wet gangrene?

Bacteria are present in wet gangrene but absent in dry gangrene Signup and view all the answers

What is the characteristic feature of traumatic fat necrosis?

Due to trauma to superficial adipose tissue Signup and view all the answers

Study Notes

Necrosis

Necrosis is a pathologic process that occurs as a consequence of severe injury.
It is characterized by the death of cells or tissues, leading to a range of effects depending on the type of necrosis.

Types of Necrosis

Coagulative necrosis:
- Most commonly seen in hypoxic death of tissues except the brain (e.g., kidney, heart, and adrenal glands).
- Characterized by preservation of basic structural outline and tissue architecture.
- Gross: Affected area is pale and firm, with a rim of hyperemia.
- Histology: Affected cells are acidophilic, opaque, and lack a nucleus.
Liquefactive necrosis:
- Typically seen in hypoxic death of brain tissue or focal bacterial/fungal lesions.
- Characterized by digestion of dead cells, resulting in a liquid, viscous mass.
- Gross: Affected area is soft, liquid, and viscous, potentially with a creamy yellow appearance due to pus.
- Histology: Amorphous acidophilic fluid with complete destruction of cells.
Gangrenous necrosis:
- A combination of coagulative and liquefactive necrosis caused by bacteria and attracted leucocytes.
- Can be classified as dry or wet gangrene, depending on the predominance of coagulative or liquefactive necrosis.
Caseous necrosis:
- Seen in foci of tuberculous infection.
- Characterized by a hypersensitivity reaction to lipopolysaccharide in the cell wall of tubercle bacilli.
- Gross: Affected area appears soft, friable, and white, with a cheesy material.
- Histology: Pink, amorphous, granular debris enclosed within a granulomatous reaction.
Fat necrosis:
- Focal area of fat destruction seen in acute hemorrhagic pancreatitis.
- Characterized by the release of activated pancreatic lipases, leading to fat saponification.
- Gross: Variegated appearance, with gray-white necrotic areas, black hemorrhage areas, and amorphous opaque chalky white deposits.
- Histology: Amorphous granular deposits on the shadowy outline of necrotic fat cells, surrounded by inflammatory reaction.
Fibrinoid necrosis:
- A special form of necrosis seen in immune reactions involving blood vessels (immunologically mediated vasculitis).
- Characterized by the deposition of immune complexes and fibrin in the wall of arteries.
- Histology: Bright pink and amorphous appearances in H&E stains.

Gangrene

Dry gangrene:
- Mainly caused by arterial occlusion, resulting in coagulative necrosis.
- Typically seen in limbs.
- Gross: Organ is dry, shrunken, and black.
- Line of demarcation: Present at junction between healthy and gangrenous parts.
- Putrefaction: Limited, with little or no septicaemia.
Wet gangrene:
- Caused by venous occlusion followed by secondary bacterial infection, resulting in liquefactive necrosis.
- Typically seen in limbs and bowel.
- Gross: Organ is moist, soft, and swollen.
- Line of demarcation: Not clear.
- Putrefaction: Marked, with overwhelming septicaemia present.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

Assess your understanding of necrosis and gangrene, including their definitions, types, and clinical examples. This quiz covers coagulative, liquefactive, caseous, fat, and fibrinoid necrosis, as well as dry and wet gangrene.