Inflammation and Pulmonary Fibrosis

The development of pulmonary fibrosis is the end point of a wide range of respiratory diseases including organic and inorganic dust exposure, pulmonary infection, acute lung injury, radiation, the idiopathic interstitial pneumonias (IIP), and connective tissue diseases. The most common fibrotic lung disorder is idiopathic pulmonary fibrosis (IPF), an IIP with the histological appearance of usual interstitial pneumonia (UIP). Formerly also known as cryptogenic fibrosing alveolitis (CFA), the definition of this disease has evolved in recent years to exclude fibrotic non-specific interstitial pneumonia (NSIP), a histological sub-type of IIP with more diffuse interstitial pulmonary fibrosis, a different clinical course and better prognosis than IPF. This change in definition must be considered when looking at historical studies that grouped UIP and NSIP under the same umbrella term.