Hypersensitivity pneumonitis is inflammation of the lungs caused by inhaling dust, mold or mildew, especially among groups working in areas exposed to these substances. But also it occurs as a result of exposure to heating, air conditioning, and some chemicals. A typical case of neumotitis is lung disease that often affects people who work with poultry and are exposed to the protein found in their feathers and droppings, and farmers, in constant contact with dust, hay, straw or grains. This condition can become, over time, a lasting or chronic lung disease. The most common symptoms are chills, cough, fever, malaise and difficulty breathing. In the most extreme cases there may be cough, shortness of breath, loss of appetite and unintended weight loss. If the underlying cause pneumonitis (eg, where the contact with some substances in the workplace) the solution is to avoid such contact and establish a medical treatment, usually with glucocorticoids known.