Clinical History
A 37-year-old man with a history of dyspnea, dry cough and weight loss, significantly worsen in years. Similarly, the restrictive ventilatory defect and impairment of DLco got worse during our observation. Besides, lung CT examinations were carried out at diagnosis and during the follow-up period.
Imaging Findings
At diagnosis, in upper and middle zones, CT showed focal irregular pleural thickenings, some thickened interlobular septa and bilateral bronchiectasis, the main airways were slightly dilated and distorted. The inferior zones were relatively spared (Fig. 1).
After a short follow-up period, due to clinical and functional progressive worsening and impairment of CT findings, a surgical biopsy was performed.
On follow-up CT four year later pleural thickenings and subpleural consolidations are markedly increased in extension, and in addition interlobular septa and peribronchovascular bundle are progressively involved in all lung regions, leading to an important architectural distortion (Fig. 2). These lesions involve the upper, middle and lower zones of both lungs, with a predominance of the upper zones (Fig. 3). Additional features include traction bronchiectasis, further luminal enlargement of trachea and bronchi, dilation of oesophagus, and bilateral lung volume loss.
The histopathological result documented findings consistent with pleuroparenchymal fibroelastosis (PPFE).
Discussion
PPFE is a disease that was first described in the English literature by Frankel et al. in 2004, and was recently added to the new classification of IIPs as a rare form.
PPFE comprises dense established intra-alveolar fibrosis, with the alveolar walls in these areas showing prominent elastosis, and dense fibrous thickening of the visceral subpleura; these changes have a striking upper-zone predominance [1].
Clinically, the patients presented with the most frequently described “triad”: dyspnoea, dry cough and weight loss. The annual impairment in the respiratory function is marked, and is similar to or more rapid than that observed for chronic fibrosing interstitial pneumonias such as UIP and fibrotic nonspecific interstitial pneumonia. The clinical course of this disease is progressive and almost all patients clinically and functionally deteriorate even over a relatively short follow-up period. Moreover, the prognosis of PPFE patients has been reported to be poor [1].
Histophathological findings are thickened visceral pleura and subpleural fibrosis consisting of dense collagen and elastin. Transition from pathological to normal parenchyma is abrupt. Fibroblast foci and lymphocytic inflammation is variably observed [2]. Aetiology is unknown but recurrent infections (in particular by aspergillus species), autoimmune diseases and genetic predisposition seem to be linked. Several case reports of patients who developed PPFE after they underwent bone marrow transplantation have been published [2, 3]. It is interesting to underline that the previous medical history of our patient was unremarkable, and no risk factor for PPFE was identified. Moreover, during the last year of observation, the patient developed dyspnoea on exertion and eventually at rest, due to progressive worsening of respiratory failure with CO2 retention. Currently, he is on treatment with high flow nasal cannula oxygen therapy (HFNCO), and is listed for lung transplantation.
HRCT studies of PPFE show subpleural reticular opacities initially favouring the upper zones with pleural fibrosis and linear or wedge-shaped extensions down secondary lobular septa. The mid- and lower zones are initially spared but are progressively enveloped with time. Additional features include volume loss, traction bronchiectasis and honeycomb, moreover pneumothorax (uni- or bilateral) and pneumomediastinum may be present [3, 4].
Finally, there are no established therapeutic options available for PPFE except for supportive care and lung transplantation.
Differential Diagnosis List
Pleuroparenchymal fibroelastosis
Chronic hypersensitivity pneumonia
Asbestosis
Final Diagnosis
Pleuroparenchymal fibroelastosis
