Obstructive Lung Disease - Pathology

Question 1

At what anatomic levels does obstructive lung disease typically occur? (3 places)

Answer 1

Bronchi.
Small airways (bronchioles).
Acini (respiratory bronchioles and alveolated parenchyma).

Question 2

Obstructive lung disease has increased resistance to airflow. How does this resistance happen? (2 types of cause)

Answer 2

Physical obstruction: mucus, inflammation, bronchospasm, fibrosis.
Destruction of airspaces -> premature closure of airways.

Question 3

What causes the airflow obstruction in bronchial asthma?

Answer 3

Constriction by bronchospasm.

Thickening of airways (edema / inflammation/ mucus and debris in lumen)

Question 4

Some histology buzzwords for bronchial asthma?

Answer 4

Sloughed off epithelium.
Edema and chronic inflammation and in bronchial walls. 
Thickened basement membrane.
Many eosinophils.
Excess asthma. *rather, "mucus"*

Question 5

What can happen to submucosal glands in asthma?

Answer 5

Hypertrophy -> increased mucus production.

Question 6

How does the basement membrane change in asthma?

How about smooth muscle?

Answer 6

They both thicken - subepithelial fibrosis, smooth muscle hypertrophy.

Question 7

What happens to goblet cells in asthma?

Answer 7

They go from “inconspicuous” to plentiful.

goblet cell metaplasia

Question 8

2 changes shown in the gross picture of fatal asthma?

Answer 8

Areas of hyperinflation, areas of atelectasis (alveolar collapse).

Question 9

How does the cellular infiltrate vary between asthma and chronic bronchitis?

Answer 9

Asthma - many eosinophils.

Chronic bronchitis - chronic inflammatory infiltrate.

Question 10

Does the submucosal glands hypertrophy in chronic bronchitis?

Answer 10

Yes they do.

Question 11

What can happen to the bronchial epithelium in chronic bronchitis?

Answer 11

Squamous metaplasia.

Question 12

When there’s fatal chronic bronchitis, what causes death?

Answer 12

Mucus plugging.

Question 13

What’s an anatomical-ish reason for why bronchiectasis develops?

Answer 13

Bronchiectasis often develops after an obstruction.
(Though… as per the bronchiectasis lecture, there are many other etiologies.. such as CF and primary cilia dysfunction.)

Question 14

3 kinds of obstruction that can lead to bronchiectasis?

Answer 14

Tumor.
Foreign body.
Mucus oversecretion (chronic bronchitis/asthma).

Question 15

Why might you confuse bronchiectasis for an abscess on histology?

Answer 15

The lumen will be filled with a purulent exudate.

though the examples we’ve seen still have the bronchiolar epithelium intact

Question 16

There’s often squamous metaplasia in bronchiectasis, too.

Answer 16

Okay.

Question 17

In emphysema, what part of the bronchial tree?

Answer 17

Airspaces distal to terminal (nonrespiratory) bronchioles are permenantly enlarged / alveoli are damaged.

Question 18

3 variants of emphysema, based on location within the lobule?

Answer 18

Centrilobular (aka. centriacinar)
Panlobular
Paraseptal

Question 19

With what major risk factor is centrilobular emphysema associated?
What area of the lungs does it most affect?

Answer 19

Associated with smoking.

Affects the apices.

Question 20

Histologic buzzwords for centrilobular emphysema?

Answer 20

“holes in the lung” - damaged areas surrounded by relatively normal alveoli.
Damage areas are “likely areas of particle/toxin deposition.”

Question 21

With what disease is panlobular (panacinar) emphysema associated?
What area of the lungs does it most affect?

Answer 21

Alpha-1 antitrypsin deficiency.

Most affects the lower lobes.

Question 22

Histologic buzzwords for panlobular emphysema

Answer 22

More uniform “hole” distribution in parenchyma - damaged areas aren’t surrounded by normal tissue.

Question 23

What’s paraseptal emphysema?

What’s a common complication of it?

Answer 23

Damage happens at most distal portions of the lung - near the pleura.
It’s creates a high risk for spontaneous pneumothorax / bulla formation.