Extrinsic Allergic Alveolitis (ILD) Flashcards
What is extrinsic allergic alveolitis?
It is a Type 3 hypersensitivity reaction, which means that it is associated with the deposition if IgG and immune complexes. This hypersensitivity occurs in sensitized individuals following inhalation of an allergen.
What causes farmers lung?
Spores from hay
What causes pigeon fanciers lung?
Protein in bird poo
What causes malt workers lung?
Aspergillus from malt
What is the presentation of acute extrinsic allergic alveolitis?
Flu like symptoms, fevers, rigors, myalgia, dry cough, SOB, and crackles but no wheeze 4-6 hours after exposure
What is the presentation of chronic extrinsic allergic alveolitis?
Increasing SOB, exertional SOB, weight loss, type 1 respiratory failure, cor pulmonale
What investigations can be done for acute extrinsic allergic alveolitis?
Bloods, CXR and Spirometry
What investigations can be done for chronic extrinsic allergic alveolitis?
Bloods, CXR, Spirometry and DCLO
What blood results would be indicative of acute extrinsic allergic alveolitis?
Neutrophillia and increased ESR
What CXR results would be indicative of acute extrinsic allergic alveolitis?
Upper zone consolidation
What spirometry results would be indicative of acute extrinsic allergic alveolitis?
Reversible restrictive pattern
What blood results would be indicative of chronic extrinsic allergic alveolitis?
Positive serum precipitans
What CXR results would be indicative of chronic extrinsic allergic alveolitis?
Upper lobe fibrosis (i.e. honeycomb lung)
What spirometry results would be indicative of chronic extrinsic allergic alveolitis?
Restrictive pattern
What DCLO results would be indicative of chronic extrinsic allergic alveolitis?
Reduced
