hypersensitivity pneumonitis

pathology

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Last updated

June 17, 2026

Quick Summary

Hypersensitivity pneumonitis is a group of lung conditions caused by an allergic reaction to inhaled organic dusts. These dusts can come from sources like moldy hay (farmer's lung), bird droppings (pigeon breeder's lung), or contaminated humidifiers.12

When re-exposed, the lungs become inflamed, leading to symptoms such as shortness of breath, fever, cough, and general illness. In chronic cases, this inflammation can cause permanent lung damage, including pulmonary fibrosis. The primary treatment involves avoiding the offending dusts.21

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farmer’s lung
…diseases that are categorized as hypersensitivity pneumonitis; these include pigeon breeder’s lung (also called bird fancier’s, or bird breeder’s, lung), mushroom worker’s lung, cheesewasher’s lung, and coffee worker’s lung.
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…diseases that are categorized as hypersensitivity pneumonitis; these include pigeon breeder’s lung (also called bird fancier’s, or bird breeder’s, lung), mushroom worker’s lung, cheesewasher’s lung, and coffee worker’s lung.
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respiratory disease
Hypersensitivity pneumonitis
Hypersensitivity pneumonitis is an important group of conditions in which the lung is sensitized by contact with a variety of agents and in which the response to reexposure consists of an acute pneumonitis, with inflammation of the smaller bronchioles, alveolar wall edema, and a…
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Hypersensitivity pneumonitis is an important group of conditions in which the lung is sensitized by contact with a variety of agents and in which the response to reexposure consists of an acute pneumonitis, with inflammation of the smaller bronchioles, alveolar wall edema, and a…
Read More