Inflammation

Question 1

Tuberculosis is a disease that produces foci of chronic inflammation in the
lung. If a biopsy of tissue from such a focus were examined, immune cells of
which of the following types would you expect?

Answer 1

Macrophages, monocytes and lymphocytes are expected in chronic granuloma inflammation.

Question 2

What are some things that can trigger a mast cell as an inflammatory mediator?

Answer 2

1. IgE release
2. C3a/ C5a
3. allergens

Question 3

What 3 events occur as mast cells are being activated by IgE?

Answer 3

Crosslinking of IgE to mast cell receptors stimulates:

1. Degranulation of histamine
2. Cytokines
3. Eicosanoids (prostaglandings, leukotrienes)

Question 4

Histamine causes the leakage of what type of circulatory vessels?

Answer 4

Leakage is confined to post-capillary venules.

Question 5

Define histamine’s biggest change on the blood vessel wall.

Answer 5

Opening of inter-endothelial junctions to allow leakage as contents of blood are exposed to the basement membrane.

Question 6

During local inflammation, describe what occurs in the process of stasis.

Answer 6

Blood viscosity increases with local hematocrit to slow down local blood flow just before WBCs migrate to site.

Question 7

What are the 2 cell adhesion molecules that interact with WBCs during leukocyte migration?

Answer 7

1. ICAM-1 interacts with CD11/CD18 of WBC

2. VCAM interacts with VLA-4 on WBC

Question 8

When a bacteria is engulfed, what metabolic pathway increases in rate?

Answer 8

HMP Pathway increases NADPH and NADH needed for phagocytosis. This increases overall metabolic function of the phagocyte.

Question 9

What is NADPH needed to make to help phagocytes kill engulfed pathogens? What is the significance of this?

Answer 9

NADPH helps make O2 radicals and H2O2 for bacterial killing, in a process known as oxidative burst. The reactive H2O2 is broken down by catalase, but lack of it in a phagocyte accounts for the short lifetime.

Question 10

Describe Chronic Granulomatous Disease (inheritance pattern, leukocyte defect, symptoms).

Answer 10

CGD is an autosomal recessive disease that usually affects males. A lack of NADH/NADPH activity (from decreased oxidative burst) has affected children suffer with recurrent infections of the skin, lymph nodes, lung and bone. Common findings include granulomas or lipid-filled abscesses.

Question 11

Describe what occurs in Chediak-Higashi Syndrome (inheritance pattern, leukocyte defect, symptoms).

Answer 11

CH is an autosomal recessive disorder in which leukocytes don’t function as well since mutations affect proteins for lysosomal membrane trafficking. Symptoms include hypo-pigmentation, recurrent lung and viral infections and increased azurophilic granules in neutrophils.

Question 12

What complements serve as chemotactic agents for leukocyte activation and migration?

Answer 12

Complements C3a and C5a are chemotactic.

Question 13

How does chronic inflammation differ from that of acute?

Answer 13

Irreversible changes occur in the tissue in which new blood vessels are formed and CT appears as scars from granulation by fibroblasts.

Question 14

Angiogenesis can be stimulated by _____ and _____. Describe the significance of one of these stimulants.

Answer 14

Inflammatory chemokines and hypoxia. Chemokines act indirectly by attracting leukocytes that secrete pro-angiogenic factors such as VEGF.

Question 15

What role does the cytokine TGF-beta have in inflammation?

Answer 15

In chronic inflammation, TGF-beta is important for fibrosis (avascular scar-formation).

Question 16

What are some features in Interstitial pulmonary fibrosis?

Answer 16

• Honey-combed appearance of the lung from loss of alveoli

- enormous increase in fibrous tissue (pulmonary fibrosis) and air space

Question 17

Define what an abscess is in context of inflammation.

Answer 17

Abscess is a pus-filled granuloma that’s avascular in the interior. This destroys surrounding tissue.

Question 18

Define empyema.

Answer 18

Build up of pus in an “existing” body cavity such as the pericardial sac of pleural space.

Question 19

What is the key feature of Granulomatous inflammation?

Answer 19

Appearance of multinucleated giant cells and lesions that form because the many macrophages are unable to clear the offending agent. This is the last mode of protection.

Question 20

Describe the key features of Tuberculosis.

Answer 20

• Ghon complex in which calcified granuloma are present in lung tissue (looks like cottage cheese = “Caseation”)
• secondary TB features disseminated lung granulomas
• mycobacterium stained pink with acid fast stain

Question 21

What does a peripheral smear with band cells indicate?

Answer 21

Immature neutrophils (band cells) in a peripheral blood smear indicates an acute infection.

Question 22

Silicon breast augmentation after a mastectomy puts a patient at risk for developing what type of inflammatory response?

Answer 22

Chronic granulomatous inflammation: in which silicon that’s seen as foreign material can result in dense fibrosis from TGF-beta cytokines.

Question 23

List the 5 steps that occurs for neutrophil infiltration into a tissue during inflammation.

Answer 23

1. Margination
2. Rolling via selectins
3. Adhesion via integrins
4. Migration across the vessel wall
5. Migration through tissues.

Question 24

Describe 3 features that may appear in a patient with Acute Pyelonephritis.

Answer 24

1. Renal scarring showing protein in the urine
2. Sepsis as indicated by bacteria (i.e. E. coli) in the urine
3. loci of acute inflammation (necrosis and hemorrhage) with indicated PMNs in a renal biopsy.

Question 25

What type of inflammation is a blister from a skin burn?

Answer 25

Serous inflammation that may develop pus underneath.