Bronchitis

Question 1

Chronic bronchitis criteria:

Answer 1

Persistent cough for 3 months in 2 consecutive years without identifiable cause.

Question 2

3 types of chronic bronchitis:

Answer 2

1. Simple: productive cough without evidence of airflow obstruction.
2. Asthmatic: hyperreactive airways with intermittent bronchospasms and wheezing.
3. Obstructive: emphysema (smokers)

Question 3

Chronic bronchitis pathogenesis:

Answer 3

1. Hypersecretion of mucous in large airways (neutrophil proteases).
2. Increase of goblet cells
3. Other EGF pathways (MUC 5AC)
4. Leads to sputum overproduction.
5. Bronchiolitis: small airways (bronchi, bronchioles)–> goblet cell metaplasia, pigmented alveolar mac’s, inflammatory infiltrate, fibrosis of bronchiolar wall

Question 4

Pathogenesis of chronic bronchitis due to smoking:

Answer 4

1. Impaired ciliary escalator
2. Direct epithelial damage
3. Inhibits leukocyte clearing.

Question 5

What is the gross appearance of chronic bronchitis?

Answer 5

Hyperemia
Swelling
Edema
Mucopurulent secretions
Casts of secretions and pus in bronchi and bronchioles.

Question 6

Microscopic/histologic changes seen in chronic bronchitis

Answer 6

1. Chronic inflammation
2. Enlargement of the mucous glands of trachea and bronchi.
3. Increased goblet cells
4. Increased size of mucous glands (reid index): normal is 0.4; relates to severity and duration of disease
5. Squamous metaplasia and dysplasia.
6. Bronchiole narrowing and luminal fibrosis.

Question 7

Clinical progression of chronic bronchitis:

Answer 7

Takes years
Hypercapnia
Hypoxemia
Mild Cyanosis
Cor PUlmonale
Death

Question 8

What is Asthma?

Answer 8

1. Chronic inflammatory disorder.
2. Wheezing, breathlessness, chest tightness, cough.
3. Worst at night/early morning
4. Diffuse bronchoconstriction
5. Airflow limitation
6. Inflammation predisposes to responsiveness (bronchospasm)

Question 9

What can cause an asthma attack?

Answer 9

Cold
Exercise
Allergen (pre-sensitized)
Increasing in Western culture for no known reason.

Question 10

What is extrinsic asthma?

Answer 10

Type I hypersensitivity reaction to an extrinsic antigen

Question 11

What is intrinsic asthma?

Answer 11

A response to nonimmune mechanisms: cold, stress, etc.

Question 12

Pathogenesis of asthma

Answer 12

Poorly understood:
T2 helper cells (CD4) secrete IL’s
Stimulate B cells to produce IgE
T1 helper cells (CD4) produce INF gamma and IL-2 (initiates viral/intracellular killing via macs and cytotoxic t-cells).
Create loop (with different inciting agents).

Question 13

What is atopic asthma?

Answer 13

Most common type
Begins in childhood
Due to environmental stimuli (extrinsi or intrinsic)

Question 14

What is non-atopic asthma?

Answer 14

Triggered by respiratory tract infection (viral»bacterial)
Normal IgE serology
Negative skin test

Question 15

Drug induced asthma is?

Answer 15

Uncommon
Aspirin induced w/urticarial
COX- pathway of arachidonic acid inhibited while lipoxygenase is unaffected

Question 16

What is the morphology of asthma?

Answer 16

Overdistended lungs.
Small foci of atelectasis.
Mucous plugs
Shed epithelium: curshmann spirals, eosinophils, charcot-leyden crystals.
Thickening of bronchial epithelium BM. 
Edema and inflammatory infiltrate (eosinophils and mast cells)
Increase in size of submucosal glands
Bronchial wall muscular hypertrophy