Practical 4: Inflammation

Question 1

What is inflammation

Answer 1

A process by which the body attempts to deal with injury to the tissues

Such damage may be caused by a variety of physical, chemical or biological agents

In the inflammatory response the body attempts to eliminate or neutralise injurious agents and repair the tissues

Question 2

What are three diseases whereby acute inflammation takes place

Answer 2

Gastric ulcer

Bacterial pneumonia

Appendix with acute inflammation

Question 3

What is acute inflammation

Answer 3

The initial series of events following injury to a tissue, directed towards neutralizing the injurious agents and restoring the tissues to useful function

Cells involved are the neutrophil

Question 4

What does the outcome of acute inflammation depend on?
(3)

Answer 4

The degree of tissue damage
The nature of the injurious agent
The type of tissue involved

Question 5

What are three tissue responses to acute inflammation

Answer 5

Resolution

Organisation and repair

Inflammatory exudate

Question 6

What is resolution

Answer 6

When tissue damage is minimal, the exudate is reabsorbed into local vessels and no evidence of injury remains

Question 7

What is organisation and repair

Answer 7

Where tissue damage is more extensive.

In this process the dead tissue is phagocytosed and the necrotic area is replaced with granulation tissue composed of a vascularised connective tissue laid down by fibroblasts

The capillaries disappear when fibrous repair is complete with the formation of scar tissue at the site of the original tissue destruction

Question 8

What is organisation and repair

Answer 8

Where tissue damage is more extensive.

In this process the dead tissue is phagocytosed and the necrotic area is replaced with granulation tissue composed of a vascularised connective tissue laid down by fibroblasts

The capillaries disappear when fibrous repair is complete with the formation of scar tissue at the site of the original tissue destruction

Question 9

What is inflammatory exudate

Answer 9

Composed of serum, leucocytes (mostly PMLs? and fibrin

Question 10

What is chronic inflammation
(3)

Answer 10

Results from persistence of injurious stimulus over a long period of time causing continuing tissue damage

It most commonly follows acute inflammation where the process has failed to eradicate the causative agent

Areas of acute inflammation may persist in chronic inflammation

Question 11

What is chronic inflammation
(3)

Answer 11

Results from persistence of injurious stimulus over a long period of time causing continuing tissue damage

It most commonly follows acute inflammation where the process has failed to eradicate the causative agent

Areas of acute inflammation may persist in chronic inflammation

Question 12

What are some features of chronic inflammation

Answer 12

Change in cellular infiltrate: to consist of lymphocytes and plasma cells

Stromal changes: due to deposition of connective tissue components (scar formation)

Formation of granulomas

Question 13

What are granulomas
(2)

Answer 13

An organised collection of inflammatory cells including activated macrophages (epitheliod histiocytes), Langhand’s giant cells (multinucleated macrophages) and lymphocytes

Granulomas are associated with M. tuberculosis infections where organism is resistant to destruction by neutrophils and fail to excite a strong acute reaction

Question 14

Define exudate

Answer 14

Acute inflammation exudate can be:
- purulent: Neutrophils dominate
- Fibrinous: fibrin abundant
- Serous: fluid is major component

Question 15

Define granulation tissue
(2)

Answer 15

When tissue damage is extensive, the exudate undergoes a process called organisation and repair

In this process the dead tissue is phagocytosed and the necrotic area is replaced with granulation tissue composed of a vascularised connective tissue laid down by fibroblasts

Question 16

Define hyperaemia

Answer 16

An increase in the amount of blood in the tissue

Typically seen in acute inflammation due to the release of histamine which stimulated blood flow to the area

Question 17

Define granuloma

Answer 17

Some microorganisms are resistant to destruction by neutrophils and
fail to excite a strong acute reaction. The initial neutrophil response is usually sparse
and is quickly followed by a macrophage response. This local accumulation of
macrophages produces a discrete lesion called a granuloma

Question 18

Define giant cell
(2)

Answer 18

Activated macrophages enlarge and sometimes fuse to form multinucleated giant cells (Langhan’s giant cells)

Seen at the edge of the granuloma

Question 19

Write about the normal mucosa of the stomach
(3)

Answer 19

Simple columnar cells -> a single layer of columnar cells attached to the basement membrane, with oval-shaped nuclei located in the basal region

Epithelium is towards the top of the mucosal layer of the stomach

Mucosa of the stomach contains many other types of secretory cells

Question 20

Write about the normal mucosa of the stomach
(3)

Answer 20

Simple columnar cells -> a single layer of columnar cells attached to the basement membrane, with oval-shaped nuclei located in the basal region

Epithelium is towards the top of the mucosal layer of the stomach

Mucosa of the stomach contains many other types of secretory cells

Question 21

Write about gastric ulcers

Answer 21

Acute inflammation

Granulation tissue, fibrous area, cellular exudate all seen

Area closest to lumen affected first

May be able to see some blood

Should be able to see some neutrophils

Blue staining fibrous layer

May see granulation tissue/scarring

Gastric flare up is acute

Striated bands = scarring tissue

May be able to see neutrophil migration in the capillaries

Question 22

What may cause ulcers?
(7)

Answer 22

Smoking
Bad diet
Alcohol
Hereditary causes

High acid erodes mucosa to form ulcers

NSAIs -> non-steroidal anti-inflammatory drugs also causes ulcers

It may heal, could become chronic, could form a perforation which is life threatening -> cause must be treated in order to heal

Question 23

Write about pneumonia
(3)

Answer 23

Hyperaemia -> blood in alveolar wall

Thickened alveolar walls

Usually sick for three weeks but inflammation is always neutrophilic/acute. This is strange for disease

Should still be able to tell its lung tissue

Question 24

Give three examples of acute infections which last longer than 3 days

Answer 24

Ulcerative colitis and gastric ulcers also remain as acute inflammation

Pneumonia

Question 25

Write about the appendix
(9)

Answer 25

Start of large intestine
Part of lymphoid system
Can become inflamed in some people
Inflammatory cells are found in normal tissue
Screens samples of matter from intestine
Appendicitis is a neutrophilic response
Architecture is destroyed
Appendix can’t recover
Usually bacteria causes an infection
If chronically inflammed it is at risk of bursting -> usually doesn’t get the chance to do this

Question 26

What are four examples of chronic inflammation

Answer 26

PCP pneumonia

Hashimoto’s thyroiditis

Cervicitis

Tuberculosis in the lung

Question 27

What is PCP pneumonia
(3)

Answer 27

Fungal pneumonia caused by pneumocystis jirovecii

Only seen in immunocompromised patients e.g. HIV patients or cancer patients or those on immunosuppressents

Life threatening infection -> immediate hospitalisation

Forms foamy mass in airspace

Grocotts methenamine silver

Question 28

What is cervicitis?
(6)

Answer 28

Stratified squamous epithelium in normal

Disease = blue staining lymphocytes

Mucosa changes to glandular

Groups of lymphocytes will be seen

Caused by infections (Not HPV) but could be candida infection that hasn’t cleared

Will see lots of plasma cells

Question 29

What is TB?

Answer 29

Destroys normal lung tissue

Round structures form granulomas

Doesn’t look like lung tissue

Casesous necrosis

Granulomas called tubercles

Langhan’s Giant cells

Flat macrophages at outside of granuloma (pathognomic cells)

ZN stain for TB