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Highlights & Basics
- Hypersensitivity pneumonitis (HP) is an inflammation of the alveoli and distal bronchioles caused by an immune response to inhaled allergens.
- Exposure to an antigen is the key epidemiologic factor - most commonly including Actinomycetes bacteria, animal proteins, or reactive chemicals.
- Diagnosis requires a high index of suspicion when evaluating individuals with interstitial lung disease or recurrent flu-like illness.
- Various tests may be used to corroborate a presumptive diagnosis, but no test is pathognomonic.
- Treatment involves avoidance of the causative agent and use of corticosteroids.
Quick Reference
History & Exam
Key Factors
Other Factors
Diagnostics Tests
Treatment Options
Definition
Epidemiology
Etiology
Pathophysiology
Citations
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Quirce S, Vandenplas O, Campo P, et al. Occupational hypersensitivity pneumonitis: an EAACI position paper. Allergy. 2016 Jun;71(6):765-79.[Abstract][Full Text]
Fernández Pérez ER, Travis WD, Lynch DA, et al. Diagnosis and evaluation of hypersensitivity pneumonitis: CHEST guideline and expert panel report. Chest. 2021 Aug;160(2):e97-156.[Abstract][Full Text]
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