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Medical Author:

George Schiffman, MD, FCCP

George Schiffman, MD, FCCP

Dr. Schiffman received his B.S. degree with High Honors in biology from Hobart College in 1976. He then moved to Chicago where he studied biochemistry at the University of Illinois, Chicago Circle. He attended Rush Medical College where he received his M.D. degree in 1982 and was elected to the Alpha Omega Alpha Medical Honor Society. He completed his Internal Medicine internship and residency at the University of California, Irvine.

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Medical Editor:

Melissa Conrad Stöppler, MD

Melissa Conrad Stöppler, MD

Melissa Conrad Stöppler, MD, is a U.S. board-certified Anatomic Pathologist with subspecialty training in the fields of Experimental and Molecular Pathology. Dr. Stöppler's educational background includes a BA with Highest Distinction from the University of Virginia and an MD from the University of North Carolina. She completed residency training in Anatomic Pathology at Georgetown University followed by subspecialty fellowship training in molecular diagnostics and experimental pathology.

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In this Article

• What is hypersensitivity pneumonitis and what are its causes?
• What is acute hypersensitivity pneumonitis?
• What are the symptoms of acute hypersensitivity pneumonitis?
• What is chronic hypersensitivity pneumonitis?
• What are the symptoms of chronic hypersensitivity pneumonitis?
• What are examples of hypersensitivity pneumonitis?
• How is hypersensitivity pneumonitis diagnosed?
• What is the treatment for hypersensitivity pneumonitis?
• Find a local Pulmonologist in your town
• Hypersensitivity Pneumonitis Index

Chronic (long-term) hypersensitivity pneumonitis causes lung scarring (fibrosis).

Symptoms of chronic hypersensitivity pneumonitis include:

• Shortness of breath
• Cough

Chronic disease is believed to occur after prolonged low grade exposure to the offending particles. It is sometimes quite surprising that individuals with a passion for their hobbies or occupation will continue to allow exposure to lung damage (if the offending particles are related to the hobby or job) despite the knowledge that it is harmful.

Examples of hypersensitivity pneumonitis include:

• Farmer's lung disease from exposure to mold spores in hay
• Pigeon breeder's disease from exposure to protein particles in pigeon droppings
• Sauna takers' disease from exposure to mold growing in wet containers
• Mushroom workers' disease from exposure to moldy compost
• Bagassosis from exposure to moldy sugar cane
• Winemaker's lung from exposure to a fungus on grapes called Botrytis cinerea
• An unusual case was published involving a case of hypersensitivity to Canadian goose droppings. The individual was a physician who was exposed to both indoor and outdoor antigens while living in a suburban Illinois community. One can only imagine the tremendous detective work necessary to make this diagnosis.

A more detailed analysis is listed in the table, which includes the types of compounds, bacteria, and molds known to cause hypersensitivity pneumonitis.