Definition of the pathology

Pulmonary fibrosis is a diffuse interstitial disease caused by damage to and scarring of lung tissue. Pulmonary fibrosis causes scarring and 'thickening' of the tissue surrounding the air sacs (alveoli) of the lungs, which affects lung function by preventing the normal passage of oxygen into the bloodstream. As pulmonary fibrosis progresses, lung function becomes increasingly impaired and the patient experiences increasing shortness of breath (dyspnoea).