Lung disease. X-ray of the chest of a 56 year old woman with interstitial lung disease (ILD). ILD is a group of lung diseases that affect the tissue in the alveoli (air sacs) of the lungs. Most of these diseases later develop fibrosis (the formation of thickened scar tissue) in the lungs. ILD results in loss of lung volume, impairing gaseous exchange and causing shortness of breath. In this case, the patient has amyloidosis of the lungs, where amyloid protein deposits have formed nodules (grainy white dots) inside the lungs. ILD can be caused by inhalation of irritants (such as asbestos), connective tissue diseases, lung infections or certain medications. Treatment is aimed at the underlying cause.