Clinical Diagnosis of Pleuroparenchymal Fibroelastosis

Pleuroparenchymal fibroelastosis (PPFE) is an extremely rare interstitial lung disease (ILD) characterised by fibroelastotic changes predominating in the subpleural lung parenchyma with visceral pleural fibrosis involving the upper lobes. It has distinctive clinical, radiological, and pathological manifestations. Diagnosis constitutes literally a stalemate because of its rarity, unavailability of an agreed diagnostic consensus, and requirement of tissue biopsy for an accurate final diagnosis that can not be performed in most of the patients owing to the comorbid complications of the disease itself. Identification of PPFE may also pose great difficulties due to the coexistence of other interstitial lung diseases. PPFE usually exhibits a persistently deteriorating prognostic course culminating in fatal complications including respiratory failure, pulmonary hypertension, cor pulmonale, or pneumothorax. Presence of disease relevant complications frequently preclude invasive tissue biopsy interventions in these patients leading to a diagnostic challenge for clinicians. This review aims to provide a definitive diagnosis based on entirely the clinical manifestatins of PPFE by shedding light on the pathogenesis, clinical, and radiologic findings of the disease. Histopathological tissue evaluation was also included in the diagnostic approach for patients whose condition was suitable for an invasive biopsy intervention. With this review, it is concluded that an approach consisting of exclusively clinical manifestations will ensure adequate support for an accurate PPFE diagnosis without any requirement for histopathological tissue examination.