Cell death and inflammation

Question 1

Describe the nuclear changes seen in necrosis?

Answer 1

Pyknosis - DNA condenses
Karyorrhexis - Nuclear membrane ruptures and contents fragment
Karyolysis - Enzymes break down nuclear material

Question 2

Describe the microscopic appearance of coagulative necrosis?

Answer 2

The genetic material is broken down but the tissue retains much of its cellular structure

Question 3

What are the causes of coagulative necrosis?

Answer 3

Ischaemia and haemorrhage

Question 4

What is a possible complication of coagulative necrosis?

Answer 4

Gangrene

Question 5

Describe gangrene

Answer 5

Bacteria invade the necrotic tissue and degrade via proteolysis. The tissue becomes black/green due to haemoglobin breakdown and smells foul.

Question 6

Describe the appearance of colliquative necrosis

Answer 6

Tissue appears as a liquid mass of dead cells

Question 7

What are the causes of colliquative necrosis?

Answer 7

• Cerebral infarction

- Infection from pyogenic bacteria (abscess)

Question 8

Describe the appearance of caseous necrosis

Answer 8

Tissue resembles cream cheese - structure unrecognisable

Question 9

What condition is caseous necrosis typically seen?

Answer 9

Tuberculosis

Question 10

What is amyloidosis?

Answer 10

When insoluble beta-sheets of proitein accumulate and aggregate within a tissue causing damage and impaired function.

Question 11

What is the pathophysiology of AL amyloidosis?

Answer 11

Primary amyloidosis

• Mutations cause accumulation of immunuglobin light chains
• e.g. multiple myeloma

Question 12

What is the pathophysiology of AA amyloidosis?

Answer 12

Secondary amyloidosis

• Caused by chronic inflammation
• Aggregation of amyloid pre-cursor protein

Question 13

What is dystrophic calcification?

Answer 13

• Calcification of necrotic or fibrotic tissue
• Otherwise normal calcium metabolism

e.g. atheroma of arteries

Question 14

What is metastatic calcification>

Answer 14

Calcification of normal healthy tissue due to increased calcium levels and impaired metabolism

Question 15

What is the production and role of histamine in the inflammatory response?

Answer 15

Produced by mast cells

• Causes vasodilation
• increases vascular permeability

Question 16

What is the production and function of inflammaatory cytokines?

Answer 16

Mast cells and macrophages

• Causes vascular endothelium to express adhesion molecules
• Systemically causes a fever

Question 17

How do leukocytes reach the affected area in acute inflammation?

Answer 17

• Adhere to the vascular wall via adhesion molecules (caused by inflammatory cytokines)
• Migrate through vascular wall which is permeable due to histamine

Question 18

Summarise the process of phagocytosis

Answer 18

• Leukocyte recognise and bind the foreign agent via receptors.
• Agent engulfed
• Degraded via free radicals produced by lysosome enzymes

Question 19

Describe the histopathological appearance of a granuloma/granulomatous inflammation

Answer 19

Activation and fusion of macrophages to form multinucleate giant cells

• Strong T-lymphocyte activation and presence
• May be central necrosis

Question 20

What conditions can cause granulomatous inflammation?

Answer 20

Tuberculosis, sarcoidosis

Question 21

What is the pathophysiology of Rheumatoid Arthritis?

Answer 21

• Chronic inflammation of the synovium between joints

Question 22

What is the pathophysiology of atherosclerosis

Answer 22

• Repeated injury to the vascular endothelium due to smoking/hypertension
• Recruited macrophages become mast cells due to accumulation of lipoproteins
• Plaque formation