Chronic Inflammation

Question 1

prolonged duration (weeks to months to years) in which active inflammation, tissue injury, and healing proceed simultaneously.
?

Answer 1

Chronic inflammation

Question 2

Chronic inflammation Characterized by ?

Answer 2

1. Infiltration with macrophages, lymphocytes, and
   plasma cells
   2.Tissue destruction, induced by the products of the
   inflammatory cells.
2. Repair, involving new vessel proliferation (angiogenesis)
   and fibrosis.

Question 3

Causes of chronic inflammation?

Answer 3

1. Primary chronic inflammation 2. Progression from acute inflammation: • The persistence of the injurious agent or • Interference with the normal process of
   healing.

Question 4

Causes of Primary Chronic inflammation ( i.e no initial phase of acute inflammation)?

Answer 4

1. Persistent infections by
   microbes that are difficult to
   eradicate.
2. 2- Immune-mediated
3. 3- Prolonged exposure to
   potentially toxic agents.
   Eg:

Question 5

Chronic Inflammatory Cells

Answer 5

Macrophages, 2.Lymphocytes, 3.Eosinophils

Question 6

Two major pathways of macrophage activation ?

Answer 6

1. Classical pathway 2. Alternative pathway

Question 7

Classical macrophage activation induced by

Answer 7

Induced by: 1. microbial products such as endotoxin, 2. T cell–derived signals, the cytokine IFN-γ, and 3. by foreign substances including crystals and particulate matter.

Question 8

Classically activated macrophages produce : ?

Answer 8

1. lysosomal enzymes, 2. NO, and 3. ROS,

Question 9

Classical macrophage activation

Work on ?

Answer 9

Ros and no and lysosome = Phagocytosis and killing of many bacteria / inflammation = iil 1 12 23 Chemokines

All of which enhance their ability to kill ingested organisms, and
secrete cytokines that stimulate inflammation.

• These macrophages are important in host defense against ingested
microbes and in many chronic inflammatory reactions.

Question 10

Alternative macrophage activation

Induced by?

Answer 10

Cytokines (IL-4 and IL-13, produced by T lymphocytes and other
cells, including mast cells and eosinophils.

Question 11

Alternative macrophage activation

Role ?

Answer 11

tissue repair. They secrete growth factors that promote 1. angiogenesis, 2. activate fibroblasts and 3. stimulate collagen synthesis.

Il 10 =anti inflammatory

Question 12

induce macrophages to fuse into large,

multinucleate giant cells?

Answer 12

IFN-γ

Question 13

Initiate the process of tissue repair and are involved in scar
formation and fibrosis.

Role of ?

Answer 13

Macrophages

Question 14

Display antigens to T lymphocytes and respond to signals from T
cells.
Role of ?

Answer 14

Macrophages

Question 15

2.Lymphocytes properties?

Answer 15

Two types: T and B lymphocytes which migrate into

inflammatory sites by action of chemokines. Lymphocytes interact with macrophages to kill the organism .

Question 16

3.Eosinophils properties?

Answer 16

Found in inflammatory sites around parasitic infections or as
part of immune reactions associated with allergies.

Question 17

The commonest appearances of chronic inflammation are?

Answer 17

1. Chronic ulcer, 2. Chronic abscess cavity, 3. Thickening of the wall of a hollow viscus by fibrous tissue 4. Granulomatous inflammation,

Question 18

granuloma microscopically characterized by ?

Answer 18

aggregation of
macrophages that are transformed into epithelium-like cell
(epithelioid appearance) surrounded by a collar of mononuclear
leukocytes, principally lymphocytes and occasionally plasma
cells.
• Older granulomas develop an enclosing rim of fibroblasts and
connective tissue .

Question 19

Granulomas can form under three settings:

?

Answer 19

1- With persistent T-cell responses to certain microbes (such as Mycobacterium tuberculosis, T. pallidum, or fungi), in which T cell–derived cytokines are responsible for chronic macrophage activation.
2- In a disease of unknown etiology called sarcoidosis
3- Granulomas may develop in some immune mediated inflammatory diseases, notably Crohn disease. 4- They develop in response to relatively inert foreign bodies (e.g., suture or splinter), forming so-called foreign body granulomas

Question 20

tubercle bacillus grossly ?

Answer 20

granular, cheesy appearance called caseous necrosis.

Question 21

tubercle bacillus microscopy?

Answer 21

Necrotic material appears as amorphous, structure less,
granular debris. • Focus of activated macrophages (epithelioid cells),
rimmed by fibroblasts, lymphocytes, histiocytes,
occasional Langhans giant cells. • Central necrosis with amorphous granular debris; acid-
fast bacilli • (ziehl Neelsen stain for acid fast bacilli)

Question 22

Types of giant cells ?

Answer 22

= Langhans’ giant cells Langhans’ giant cells have a horseshoe arrangement of peripheral nuclei at one pole of the cell and are characteristically seen in tuberculosis, although they may be seen in other granulomatous conditions
= Foreign body giant cells Foreign body giant cells’ are large cells with nuclei randomly scattered throughout their cytoplasm. They are characteristically seen in relation to particulate foreign body material.

Question 23

most important

mediators of the acute-phase reaction ?

Answer 23

cytokines TNF, IL-1, and IL-6 = plasma proteins

Question 24

The acute-phase response consists of ?

Answer 24

1. Fever:
2. Elevated plasma levels of acute-phase proteins:
3. Leukocytosis
4. Other manifestations of the acute-phase response include:
5. Chronic inflammation
6. In severe bacterial infections (sepsis),

Question 25

High levels of TNF cause ?

Answer 25

disseminated intravascular

coagulation (DIC), hypoglycemia, and hypotensive shock.

Question 26

wasting
syndrome called cachexia, which is mainly the result of TNF
-mediated appetite suppression and mobilization of fat stores.?

Answer 26

5.Chronic inflammation is