Extrinsic allergic alveolitis

Question 1

etiology of Extrinsic allergic alveolitis

Answer 1

immune-complex mediated tissue damage (type III hypersensitivity)

Question 2

examples of extrinsic alevolitis ?

Answer 2

bird fanciers’ lung: avian proteins from bird droppings

farmers lung: spores of Saccharopolyspora rectivirgula from wet hay (formerly Micropolyspora faeni)

malt workers’ lung: Aspergillus clavatus
mushroom workers’ lung: thermophilic actinomycetes*

Question 3

presentation of extrinsic alevolitis ?

Answer 3

acute (occurs 4-8 hrs after exposure)
dyspnoea
dry cough
fever

Question 4

chronic (occurs weeks-months after exposure)

Answer 4

lethargy
dyspnoea
productive cough
anorexia and weight loss

Question 5

cxr in Extrinsic allergic alveolitis

Answer 5

imaging: upper/mid-zone fibrosis

bronchoalveolar lavage: lymphocytosis

serologic assays for specific IgG antibodies

blood: NO eosinophilia!!!!!!

Question 6

Mx of extrinsic allergic alveoli’s ?

Answer 6

precipitating factors
oral glucocorticoids