hypersensitivity pneumonitis
Hypersensitivity pneumonitis (extrinsic allergic alveolitis) caused by inhaled allergens can progress to disabling or even fatal end-stage lung disease. The only truly effective treatment is early recognition and control of exposure.
Synopsis
CD8(+) cytotoxic lymphocytes infiltration
multinucleate giant cell granulomas
pulmonary interstitial fibrosis
small airways disease with obstruction
Etiology
occupational dusts or mists
residential exposure
- pet birds (pigeons and parakeets)
- contaminated humidifiers
- indoor molds
serum IgG containing high titers of specific antibody to the offending antigen elevated
pulmonary function tests: restrictive and diffusion defects with hypoxemia, especially after exercise
References
Patel AM, Ryu JH, Reed CE. Hypersensitivity pneumonitis: current concepts and future questions. J Allergy Clin Immunol. 2001 Nov;108(5):661-70. PMID: 11692086