Hypersensitivity pneumonitis is a lung condition where the air sacs and airways in and around your lungs become inflamed because of an allergic reaction. Hypersensitivity pneumonitis can be either chronic or acute, but it’s most common as an acute ailment. The allergic reaction that causes hypersensitivity pneumonitis is always the result of inhaling something in the environment, such as dirt, pollen, dust, mould, or others.
Hypersensitivity pneumonitis can also happen when you inhale animal products such as feed, seed, or faeces. Additionally, just because you are allergic to something in the environment does not mean a person will develop hypersensitivity pneumonitis when its inhaled. Instead, it takes exposure to large amounts of the material to cause hypersensitivity pneumonitis.
While usually minor, this condition can turn serious if your immune system reacts aggressively to the allergy, resulting in lung damage.
Because hypersensitivity pneumonitis affects the lungs, most of the symptoms you’ll experience will have to do with your breathing and lung capacity. However, because your immune system is also involved, you’ll also experience flu-like symptoms. Here are the most common signs and symptoms of hypersensitivity pneumonitis.
With acute hypersensitivity pneumonitis, your symptoms will usually start within 4-6 hours of exposure to the allergen. Symptoms will get gradually worse until they go away after 12 to 48 hours. However, it could take several weeks to fully recover and get back to your normal self. If your reaction is too severe or you struggle with chronic hypersensitivity pneumonitis, symptoms can be much worse and lead to lung scarring, aka fibrosis.
Hypersensitivity pneumonitis is caused by your immune system having an overly aggressive reaction to something that you inhaled. In most cases, your immune system gets activated because you’re allergic to whatever you inhaled. The result is that your immune system attacks the lungs, resulting in inflammation and swelling of the air sacs and airways in and around the lungs.
There are more than 300 allergens that can cause hypersensitivity pneumonitis, and here are some of the most common.
Essentially, anything harmful that can be inhaled has the potential to lead to hypersensitivity pneumonitis.
While there’s no single test to confirm hypersensitivity pneumonitis, it isn’t an overly difficult condition to diagnose. Your doctor will likely start with an examination of your symptoms and a health history. From there, they can perform the following tests.
Blood Tests to check for elevated white blood cell and antibody counts.
Chest X-rays to check for lung damage, inflammation, or scarring.
Listening to your lungs for abnormal breathing sounds.
Spirometry and other lung functioning tests to see if your lungs are functioning properly and at full capacity.
If your doctor still isn’t sure if you have hypersensitivity pneumonitis, they may perform a lung biopsy to know for sure.
As long as your hypersensitivity pneumonitis has not caused permanent lung damage, the best course of treatment is to stay away from whatever is causing your outbreaks. If your lungs are currently inflamed, your doctor will prescribe steroids to reduce inflammation and restore normal airflow.
Lung and breathing exercises are also a good way to restore your lung capacity. In serious cases, however, where you have suffered permanent lung damage and are on the verge of lung failure, you will require a lung transplant. This is necessary because there’s no way to reverse lung scarring once it has occurred.