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Signs and symptom vary between acute, subacute, and chronic types of hypersensitivity pneumonitis. If your condition is not diagnosed or well controlled by treatment, it can lead to irreversible lung damage and other potentially fatal complications.
The following are common signs and symptoms of acute, subacute, and chronic hypersensitivity pneumonitis.
While some signs and symptoms occur in several types of hypersensitivity pneumonitis, they may vary in severity. The exact signs and symptoms you experience also may vary.
Learn about how exposure history affects whether you show signs and symptoms of acute, subacute, or chronic hypersensitivity pneumonitis.
Acute hypersensitivity pneumonitis is the most common form of this condition. It is thought to occur as a result of a short period of exposure to a large amount of causative substance. Symptoms usually occur within 9 hours of being exposed again to a substance that triggers your immune system. If an additional exposure does not occur, symptoms usually resolve after a few days. Subacute and chronic forms of hypersensitivity pneumonitis occur after multiple or continuous exposures to small amounts of causative substance. Approximately 5 percent of patients develop chronic disease.
Hypersensitivity pneumonitis may cause the following potentially fatal complications if the condition is not diagnosed or well controlled by treatment.