Hypersensitivity pneumonitis (Extrinsic allergic alveolitis)

Question 1

What is another name for hypersensitivity pneumonitis?

Answer 1

Extrinsic allergic alveolitis

Question 2

What is hypersensitivity pneumonitis?

Answer 2

Hypersensitivity induced lung damage due to a variety of inhaled organic particles

Question 3

What is hypersensitivity pneumonitis mainly due to?

Answer 3

Immune-complex mediated tissue damage (type III hypersensitivity)

Question 4

What type of reaction is hypersensitivity pneumonitis?

Answer 4

Widespread inflammatory reaction

Question 5

What are the main causes of hypersensitivity pneumonitis?

Answer 5

Bird fanciers’ lung
Farmers lung
Malt workers’ lung
Mushroom workers’ lung

Question 6

What is the cause of bird fancier’s lung?

Answer 6

Avian proteins from bird droppings

Question 7

What is the main cause of farmers’ lung?

Answer 7

Spores of Saccharopolyspora rectivirgula from wet hay

Question 8

What is the cause of malt workers’ lung?

Answer 8

Aspergillus clavatus

Question 9

What is the main cause of Mushroom workers’ lung?

Answer 9

Thermophilic actinomycetes

Question 10

What are the phases of hypersensitivity pneumonitis?

Answer 10

Acute and Chronic

Question 11

When does the acute phase of extrinsic allergic alveolitis occur?

Answer 11

4- 8 hours post exposure

Question 12

How does the acute phase of hypersensitivity pneumonitis present?

Answer 12

dyspnoea
dry cough
fever

Question 13

How does the chronic phase of extrinsic allergic alveolitis present?

Answer 13

lethargy
dyspnoea
productive cough
anorexia and weight loss

Question 14

When does the chronic phase of extrinsic allergic alveolitis occur?

Answer 14

Weeks to months post exposure

Question 15

How would you diagnose hypersensitivity pneumonitis?

Answer 15

Chest x-ray

Question 16

What would you see on a chest x-ray of someone with extrinsic allergic alveolitis?

Answer 16

Upper to mid zone fibrosis

Question 17

What other investigations might you do for someone presenting with hypersensitivity pneumonitis?

Answer 17

Bronchoalveolar lavage
serologic assays
Blood test

Question 18

What might you see on bronchoalveolar lavage in someone with extrinsic allergic alveolitis?

Answer 18

Lymphocytosis

Question 19

What might you see on a serological assay in someone with hypersensitivity pneumonitis?

Answer 19

Specific IgG antibodies

Question 20

What would you not see in the blood of someone with hypersensitivity pneumonitis?

Answer 20

Eosinophilia

Question 21

What is the conservative management of extrinsic allergic alveolitis?

Answer 21

Avoid precipitating factors

Question 22

What is the medical management of hypersensitivity pneumonitis?

Answer 22

Oral glucocorticoids (40mg prednisolone)