Idiopathic pleuroparenchymal fibroelastosis (PPFE) was initially described in 2004 as a form of idiopathic interstitial pneumonia characterized by predominantly upper lobe subpleural scarring with elastosis.¹ Recently, it was recognized as a rare form of idiopathic interstitial pneumonia by the American Thoracic Society/European Society of Respiratory Diseases.^2,3 It has also been described as “idiopathic pulmonary upper lobe fibrosis.”⁴ A related, if not identical, disease was previously described as idiopathic progressive pulmonary fibrosis⁵ or “Amitani disease” in the Japanese literature. Although initially described in native lungs in patients with normal immune function, PPFE has also been reported in bone marrow transplant recipients^6,7 and in lung allografts as a manifestation of restrictive allograft syndrome.^8,9

PPFE has no gender predilection. It has been described in several patients with prior chemotherapy, including cyclophosphamide,^1,10 and has been reported in twins.¹ There is no clear association with smoking.^4,11 Symptoms include dyspnea, shortness of breath, and nonproductive cough.¹¹ A history of recurrent infections is common. Pneumothorax and pneumomediastinum occur spontaneously or as a complication of treatment and appear more common in PPFE in the setting of bone marrow transplantation.^4,7,11 Some patients have incidental pleural thickening noted on chest radiograph years prior to disease manifestation.¹⁰ Pulmonary function tests show restrictive ventilatory impairment and decrease diffusion capacity.