Idiopathic pleuroparenchymal fibroelastosis: an unrecognized or misdiagnosed entity?

Idiopathic pleuroparenchymal fibroelastosis is a rare recently described entity likely to be under- and misdiagnosed, as awareness of this entity is not yet widespread. We report two cases that show the need to include this disease in the differential diagnosis of patients with predominantly pleural and subpleural fibrotic processes. The condition is a fibrotic thickening of the pleura and subpleural parenchyma due to elastic fiber proliferation predominantly in the upper lobes. Performing elastic fiber stains routinely in patients with fibrosis of this distribution may, therefore, aid in establishing the diagnosis and differentiating it from usual interstitial pneumonia/idiopathic pulmonary fibrosis. These patients may be prone to the development of secondary spontaneous pneumothoraces and persistent postoperative bronchopleural fistulae. Continued study of newly diagnosed cases may uncover shared characteristics or features helpful in generating an etiologic hypothesis. Only with better understanding of this disease can we hope in the future to be able to offer treatments other than supportive care and ultimately lung transplantation, which are the only therapeutic options available today.