Inflammation

Question 1

What cell type is this

Answer 1

Neutrophil

Question 4

Exudate

Answer 4

Fluid released by an organism through pores or wound

Question 5

Transudate

Answer 5

Fluid accumulation but low/no protein and no cells. Often due to alterations in pressure rather than inflammation.

Question 6

Effusion

Answer 6

Fluid moving out of blood vessel into the extracellular space

Non-specific term

Question 7

What are the five categories of effusion?

Answer 7

-Serous
-Catarrhal
-Fibrinous
-Suppurative or Purulent
-Haemorrhagic

Question 8

What are the features of serous exudate?

Answer 8

Hallmark of early inflammation*
Accumulation of fluid with a low [plasma protein] and no to low numbers of leukocytes

Histology: hyperaemia (vessels filled with blood), increased clear space between tissues and dilated lymphatics

Question 9

Gross morphology of serous effusion?

Answer 9

Clear fluid exudation, swelling, vesicles, redness.

Question 10

Examples of serous exudate?

Answer 10

Thermal injury (burn)

Allergies (type I hypersensitivity)

Question 11

Catarrhal exudate features

Answer 11

Accumulation of a thick gelatinous fluid material containing abundant mucus and mucin from a mucous membrane

-occurs when there is stimulation of mucous production (GIT and respiratory tract)

Question 12

Catarrhal exudate gross morphology:

Answer 12

Clear to slightly opaque
Thick fluid

-can sometimes have neutrophils depending on severity

Question 13

Catarrhal exudate- examples

Answer 13

Chronic allergies, autoimmune diseases, infections in regions with lots of mucin producing cells (colon)

Question 14

Fibrinous inflammation and exudate

Answer 14

• accumulation of fluid with a high concentration of plasma protein and no to low numbers of leukocytes

Question 15

Fibrinous exudate gross morphology

Answer 15

Affected tissues are red (active hyperaemia) and covered with a thick, stringy, elastic, white-gray to yellow exudate that can be removed from the surface of the tissue.

Question 16

What is an example where you would see Fibrinous exudate?

Answer 16

Suggestive of more severe endothelial cell injury that allows leakage of large molecular weight proteins such as fibrinogen into the ECF- often caused by microbial infections

Question 17

Intravascular vs. Extravascular Fibrinous inflammation

Answer 17

Question 18

Suppurative/purulent exudate features

Answer 18

Accumulation of fluid with a high concentration of plasma protein and high numbers of leukocytes, predominately neutrophils

Question 19

Gross morphology of purulent exudate

Answer 19

Surfaces and/or connective tissues of the affected organs are hyperemic and covered by or contain, respectively and thick white-grey to yellow exudate (pus)

Ex. Commonly caused by bacterial infection, Suppurative mastitis

Question 20

When is Suppurative exudate classified as an acute inflammatory process?

Answer 20

If the yellow, creamy fluid is predominately composed of neutrophils and therefore this is classified as an acute inflammatory process

Question 21

Give a morphological diagnosis

Answer 21

Mammary gland; severe, diffuse, acute to subacute suppurative mastitis.

Question 22

What is the function of exudation of neutrophils?

Answer 22

• exudation of neutrophils is designed to dilute or wall off an insult
• neutrophils contain a range of substances such as reactive oxygen septics and proteolytic enzymes like myeloperozidase
  -these are antimicrobial agents designed to kill bacteria but when released into the tissues they are cytotoxic and can cause significant injury to the resident cell population contributing to tissue damage and necrosis

Question 23

Haemorrhagic exudates features

Answer 23

-accumulation of fluid containing a lot of erythrocytes

Question 24

Hemorrhagic exudates gross morphology

Answer 24

Tissues have large areas of red discolouration and fluid is opaque and red/brown

Question 25

What type of scenario would you see a hemorrhagic exudate?

Answer 25

Inflammation damaging blood vessels or a traumatic lesion

Question 26

What is the difference between Vesicles vs. Bullae

Answer 26

Vesicles: -small -fluid filled blister -formed under the epidermis -usually less than 0.5cm IF larger than 0.5cm it is considered a bullae