Idiopathic Interstitial Pneumonias

Diffuse parenchymal lung diseases (DPLDs) are a group of disorders that involve the space between the epithelial and endothelial basement membranes. Recent guidelines for the classification of DPLDs recommended separating patients into several categories, including (1) DPLDs of known cause, (2) granulomatous DPLDs, (3) rare DPLDs with well-defined clinicopathologic features, and (4) the idiopathic interstitial pneumonias (IIPs). The IIPs are further subdivided into categories that include usual interstitial pneumonia (idiopathic pulmonary fibrosis [IPF] if the usual interstitial pneumonia is idiopathic in origin) and nonspecific interstitial pneumonia. In numerous cohorts, IPF has been associated with impaired prognosis compared with nonspecific interstitial pneumonia, except in the setting of markedly impaired physiology at presentation. It is therefore imperative for the health care provider to rapidly assess the likelihood of a patient having IPF. The diagnostic approach has been refined over the past ...