Clin Mol Allergy 2017 7;15. Epub 2017 Mar 7.
Division of Sub Acute Care, Sesto San Giovanni Hospital, ASST Nord Milano, Sesto San Giovanni, Italy.
Hypersensitivity pneumonitis (HP), also called extrinsic allergic alveolitis, is a respiratory syndrome involving the lung parenchyma and specifically the alveoli, terminal bronchioli, and alveolar interstitium, due to a delayed allergic reaction. Such reaction is secondary to a repeated and prolonged inhalation of different types of organic dusts or other substances to which the patient is sensitized and hyper responsive, primarily consisting of organic dusts of animal or vegetable origin, more rarely from chemicals. The prevalence of HP is difficult to evaluate because of uncertainties in detection and misdiagnosis and lacking of widely accepted diagnostic criteria, and varies considerably depending on disease definition, diagnostic methods, exposure modalities, geographical conditions, agricultural and industrial practices, and host risk factors. Read More