Extrinsic Allergic Alveolitis

Question 1

what is extrinsic allergic alveolitis (EAA) or hypersensitivity pneumonitis?

Answer 1

condition caused by hypersensitivity induced lung damage due to a variety of inhaled organic particles

Question 2

what is extrinsic allergic alveolitis caused by?

Answer 2

• immune-complex mediated tissue damage (type III)
• delayed hypersensitivity (type IV) is thought to play a role in EAA, especially in the chronic phase

Question 3

name some examples of extrinsic allergic alveolitis

Answer 3

• bird fanciers lung
• farmers lung
• malt workers lung
• mushroom workers lung

Question 4

what is bird fanciers lung caused by?

Answer 4

avian proteins from bird droppings

Question 5

what is farmers lung caused by?

Answer 5

spores of saccharopolyspora rectivirgula from wet hay

Question 6

what is malt workers lung caused by?

Answer 6

aspergillus clavatus

Question 7

what is mushroom workers lung caused by?

Answer 7

thermophilic actinomycetes

Question 8

how does acute extrinsic allergic alveolitis present?

Answer 8

• dyspnoea
• dry cough
• fever

Question 9

when does acute extrinsic allergic alveolitis present?

Answer 9

4-8 hours after exposure

Question 10

how does chronic extrinsic allergic alveolitis present?

Answer 10

• lethargy
• dyspnoea
• productive cough
• anorexia and weight loss

Question 11

when does chronic extrinsic allergic alveolitis present?

Answer 11

occurs weeks-months after exposure

Question 12

what x-ray findings are seen in extrinsic allergic alveolitis?

Answer 12

upper/mid-zone fibrosis

Question 13

what is the management of extrinsic allergic alveolitis?

Answer 13

• avoid precipitating factors
• oral glucocorticoids