What is it?  

Hypersensitivity pneumonitis is a lung inflammation due to breathing in dust, fungus, or mould, especially among people who are exposed to these substances on a daily basis. It can also be caused by being exposed to heating, air conditioning, and some chemical substances.

Pneumopathy often affects people who work with birds and are exposed to the proteins in their feathers and droppings. It also affects farmers who are in constant contact with dust, hay, straw, or grains. Over time, this condition can become a chronic or long-lasting lung condition.    

Prognosis

Symptoms may disappear with no treatment when the trigger is avoided. As with most allergic reactions, prevention is better than the cure. If steps are taken in the early stages, prognosis is better.

What are the symptoms?

Symptoms tend to appear between four to six hours after exposure to the trigger. This makes it more difficult to make a connection.

Some of the most common symptoms are:

• chills
• cough
• fever / high temperature
• general malaise and difficulty breathing

In more extreme cases, along with shortness of breath, there is a lack of appetite and weight loss.    

Medical tests

The specialist may carry out physical examinations, as well as blood tests to find the cause for the reaction.

A chest X-ray is often done. Other tests include:  

• bronchoscopy, to examine the airways
• chest CT scan
• blood test for antibodies
• pulmonary function tests
• lung biopsy

What causes it?

Hypersensitivity pneumonitis tends to affect people who are exposed to high levels of dust, fungi, or mould. It is sometimes also triggered by being exposed to certain chemical substances or being in places with humidifiers, air conditioning, or heating at home or at work.      

How can it be prevented?    

If the cause for the hypersensitivity is known, for example certain substances at work, the specialist will recommend avoiding it and starting treatment. Glucocorticoids are commonly used to treat it.  

What is the treatment?    

The most important thing is to identify what is causing the hypersensitivity and avoid it. If the reaction is serious, asthma treatments may be used.   

What specialist should I see?

Allergists and immunologists can diagnose and treat immune system reactions, and pulmonologists or respiratory specialists diagnose and treat conditions related to the respiratory system. It is important for the specialist to check if there are any allergies to be able to identify the trigger and be able to treat the reaction.