Pneumonitis (noo-moe-NIE-tis) is a general term that refers to inflammation of lung tissue. Although pneumonia is technically a type of pneumonitis because the infection causes inflammation, most doctors are referring to other causes of lung inflammation when they use the term "pneumonitis."
Factors that can cause pneumonitis include exposure to airborne irritants at your job or while you participate in your hobbies. Some types of cancer treatments as well a dozens of drugs also can cause pneumonitis.
Difficulty breathing — often accompanied by a cough — is the most common symptom of pneumonitis. Specialized tests are necessary to make a diagnosis. Treatment focuses on avoiding irritants and reducing inflammation.
The most common sign of pneumonitis is shortness of breath, which may be accompanied by a dry cough. If pneumonitis is undetected or left untreated, you may gradually develop chronic pneumonitis. This is especially common in cases of hypersensitivity pneumonitis, in which you may be continually exposed to a lung irritant without realizing it. Signs and symptoms of chronic pneumonitis include:
When to call a doctor
Pneumonitis occurs when some irritating substance causes the tiny air sacs (alveoli) in your lungs to become inflamed. This inflammation can interfere with the delivery of oxygen to your bloodstream.
A variety of irritants, ranging from airborne molds to chemotherapy drugs, have been linked to pneumonitis. But for most people, the specific substance causing the inflammation is never identified. Pneumonitis causes may include:
Airways and air sacs of the lungs
Your bronchioles are some of the smallest airways in your lungs. Inhaled air passes through tiny ducts from the bronchioles into elastic air sacs (alveoli). The alveoli are surrounded by the alveolar-...
Occupations or hobbies
Pneumonitis that goes unnoticed or untreated can cause irreversible lung damage. Normally, air sacs within your lungs stretch and relax with each breath. Chronic inflammation of the thin tissue lining each air sac can make the air sacs scar and become inflexible — stiff like a dried sponge. This is called pulmonary fibrosis. In severe cases, pulmonary fibrosis can cause heart failure, respiratory failure and death.
Preparing for your appointment
While you may initially consult your family physician, he or she may refer you to a pulmonologist — a doctor who specializes in lung disorders.
What you can do
What to expect from your doctor
Tests and diagnosis
To distinguish pneumonitis from other lung disorders, you'll likely have one or more of the following tests.
Pulmonary function tests
Another way to assess the efficiency of your lungs is to measure the oxygen saturation in your blood with an oximeter — a device that painlessly clamps on your finger.
Surgical lung biopsy
A spirometer is a diagnostic device that measures the amount of air you're able to breathe in and out and the time it takes you to exhale completely after you take a deep breath. ...
Treatments and drugs
If you have hypersensitivity or chemical pneumonitis, avoiding allergens is a common-sense approach to treatment. By eliminating exposure to the allergen or chemical irritating your lungs, you'll likely notice that your symptoms lessen.
In severe cases of pneumonitis, treatment may include:
Lifestyle and home remedies
A diagnosis of pneumonitis may mean that you'll have to make changes to your lifestyle in order to improve your health.
For example, if your job duties expose you to substances that irritate your lungs, talk to your doctor and supervisor at work about options to protect yourself, such as wearing a pollen mask or personal dust respirator. If a hobby, such as owning birds, is causing the problem, you'll have to consider giving it up altogether.
Last Updated: 2011-06-03
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