Lower-lobe predominant pleuroparenchymal fibroelastosis

Upper-lobe predominance of elastofibrosis is agreed upon for the diagnosis of clinical pleuroparenchymal fibroelastosis (PPFE). We herein describe a patient with dermatomyositis-related interstitial pneumonia with a histology of lower-lobe predominant PPFE. A 71-year-old woman who had been diagnosed with dermatomyositis-related interstitial pneumonia died of respiratory failure. The computed tomography patterns of the lower lobes showed reticular and ground-glass opacities with traction bronchiectasis. An autopsy revealed that the bilateral lower lobes were sclerotic with decreased air volume. A microscopic examination of the lower lobes showed pleural fibrosis and subpleural elastofibrosis without the structural destruction, indicative of histological PPFE. PPFE histology was also evident in the upper lobes but relatively modest compared to that of the lower lobes. In addition, because the computed tomography images of the patient were suggestive of non-PPFE-type fibrosis, lower-lobe dominant PPFE might be overlooked in daily practice.