Idiopathic pleuroparenchymal fibroelastosis (PPFE) is a rare condition that is classified as an idiopathic interstitial pneumonia (1). It involves upper lobe fibrosis of the pleura and subpleural lung parenchyma.
1. Travis WD, Costabel U, Hansell DM, et al: An Official American Thoracic Society/European Respiratory Society Statement: Update of the International Multidisciplinary Classification of the Idiopathic Interstitial Pneumonias. Am J Respir Crit Care Med 188 (6):733–748, 2013.
The median age of presentation is around 57 years, with no sex predilection. Most patients with idiopathic pleuroparenchymal fibroelastosis are nonsmokers. Patients often report a history of recurrent infections, shortness of breath, and dry cough. Pneumothorax is common during the course of the disease.
The imaging findings in idiopathic pleuroparenchymal fibroelastosis include upper lobe thickening of the pleura and subpleural regions. Patients can have co-existing findings of other interstitial pneumonias, including usual interstitial pneumonia and nonspecific interstitial pneumonia pattern. Patients can also have areas of consolidation and bronchiectasis.
The pathology is characterized by intra-alveolar fibrosis with the alveolar walls in these areas showing prominent elastosis and dense fibrous thickening of the visceral pleura. In some patients, there is co-existent interstitial pneumonia in the lower lobes.
Surgical lung biopsy is required for confirmation of the diagnosis.