Pleuroparenchymal Fibroelastosis: Associations and Underlying Conditions

Pleuroparenchymal fibroelastosis (PPFE) is a clinicopathologic entity characterized by clinical presentation suggestive of a chronic idiopathic interstitial pneumonia, radiologic features of pleural and parenchymal involvement accentuated in the upper lobes, and a constellation of histologic findings including visceral pleural fibrosis and prominent fibroelastosis of the subpleural lung parenchyma. While the large majority of cases of PPFE have been considered idiopathic, development of PPFE in post-bone marrow transplant patients and in lung transplant recipients has recently been reported. Further, with the growing number of idiopathic PPFE cases reported in the literature, interesting patterns of association between PPFE and various clinical conditions – including prior treatment for malignancy, autoimmunity, recurrent infections, and vascular compromise/ischemia – are beginning to emerge. These associations, reviewed here, may offer clues into the pathogenesis of this rare condition.