Idiopathic pleuroparenchymal fibroelastosis (PPFE) - A case study of a rare entity

Overcoming the challenges of a misdiagnosed rare lung disease - idiopathic pleuroparenchymal fibroelastosis

Pleuroparenchymal fibroelastosis (PPFE) is a rare condition characterized by pleural and subpleural lung fibroelastosis with an upper lobe predominance. We present the third case of idiopathic PPFE from India, as well as the second ante-mortem diagnosis. A 27-year-old man presented with a 1-year history of modified Medical Research Council class II shortness of breath and dry cough. He described a 15-kg weight loss. After a clinico-radiological diagnosis, he was given anti-tubercular treatment and referred because he showed no improvement. A high-resolution computed tomography of the chest revealed bilateral upper lobe bullae, parenchymal and subpleural fibrosis, and irregular pleural thickening. PPFE was found in surgical lung and pleural biopsies. He was given systemic glucocorticoids but did not respond clinically or radiologically. Pirfenidone and a lung transplant were out of reach for him. He died 9 months after being diagnosed with his condition. Finally, idiopathic PPFE is an extremely rare entity, with only three cases reported from our subcontinent. As a result, it is easily underdiagnosed or misdiagnosed; clinician awareness of this condition is critical for better diagnosis and management.

Late pulmonary complications related to cancer treatment in children

As the number of childhood cancer survivors increases, a heightened awareness and recognition of therapy-related late effects is becoming more important. Pulmonary complications are the third leading cause of late mortality in cancer survivors. Diagnosis of these complications on chest imaging helps facilitate prompt treatment to mitigate adverse outcomes. In this review, we summarize the imaging of late pulmonary complications of cancer therapy in children and highlight characteristic findings that should be recognized by radiologists.

Pleuroparenchymal fibroelastosis in Korean patients: clinico-radiologic-pathologic features and 2-year follow-up

BACKGROUND/AIMS

Pleuroparenchymal fibroelastosis (PPFE) is a type of rare idiopathic interstitial pneumonia that is characterized by predominantly upper lobe involvement with pleural fibrosis and subjacent parenchymal fibrosis. This study aimed to determine the clinico-radiologic-pathologic features and prognosis of Korean patients with PPFE.

METHODS

A total of 26 patients who were confirmed to have PPFE by lung biopsy, were included, and their clinico-radiologic-pathologic findings were retrospectively analyzed.

RESULTS

The mean follow-up period was 23.8 months, and the mean age of the patients was 62.5 years; 61.5% were men and 50% were smokers. Cough and dyspnea were the most frequent presenting symptoms, and restrictive pattern was the most common observation in lung function. In 84.6% of the subjects, lower lobe involvement was found on chest computed tomography, and the usual interstitial pneumonia (UIP) pattern was the most common (59.1%). Among patients whose lower lobe was biopsied (n = 13), the UIP pattern was the most common (46.2%). Patients with lower lobe involvement were older and walked a shorter distance during the 6-minute walk test, compared to those without. Spontaneous pneumothorax was a common complication (26.9%), and 15.4% of the patients died mostly due to pneumonia (100%). The 1- and 3-year survival rates were 90.2% and 84.5%, respectively.

CONCLUSION

Clinical features of Korean patients with PPFE were similar to those reported previously; however, lower lobe involvement was more frequent. During follow-up, one-fourth of the patients experienced pneumothorax and one-fifth died from pneumonia.

The pathogenesis and pathology of idiopathic pleuroparenchymal fibroelastosis

Idiopathic pleuroparenchymal fibroelastosis (IPPFE) is a rare subtype of idiopathic interstitial pneumonias that consists of elastofibrosis involving the lung parenchyma and pleural collagenous fibrosis predominantly located in the upper lobes. IPPFE has various distinct clinical and physiological characteristics, including platythorax and a marked decrease of forced vital capacity with an increased residual volume on a respiratory function test. The concept of IPPFE is now widely recognized and some diagnostic criteria have been proposed. In addition, the accumulation of cases has revealed the pathological features of IPPFE. However, little is known about the pathogenesis or the process of disease formation in IPPFE. This review article will provide a summary of the pathological features and previously reported hypotheses on disease formation in IPPFE, to discuss the potential etiologies and pathogenesis of IPPFE.

Transbronchial cryobiopsy for diagnosis of pleuroparenchymal fibroelastosis

Rationale

Pleuroparenchymal fibroelastosis (PPFE) is a rare subtype of idiopathic interstitial pneumonias. PPFE mostly affects the upper lung zones and is characterized radiologically by pleural and subpleural fibrotic thickening with a reticular pattern. There is no established treatment for PPFE but lung transplantation can be considered for advanced stage. The gold standard for the diagnosis of PPFE is surgical lung biopsy (SLB) but the bronchoscopic transbronchial cryobiopsy (TBCB) is a less invasive alternative.

Patient concerns

We report here two cases in which the diagnosis of PPFE was established with the help of TBCB.

Diagnosis and interventions

Bronchoscopy with TBCB was performed under sedation with spontaneous ventilation and the help of an uncuffed ET tube.

Outcomes

Histopathology showed intra-alveolar fibroblastic proliferation with elastosis, which confirmed the diagnosis of PPFE.

Lessons

The current report demonstrates that TBCB can be a useful and safe tool to confirm the diagnosis of PPFE. According to our knowledge, this is one of few reports that shows successful diagnosis of PPFE by TBCB.

Remodeling of the pulmonary artery in idiopathic pleuroparenchymal fibroelastosis

Idiopathic pleuroparenchymal fibroelastosis (IPPFE) is a rare subtype of idiopathic interstitial pneumonia that consists of alveolar septal elastosis and intra-alveolar collagenosis, which is predominantly located in the upper lobes. The aim of this study was to examine the remodeling of the pulmonary arteries in patients with IPPFE. This study included 18 patients with IPPFE, 24 patients with idiopathic pulmonary fibrosis (IPF), and 5 patients without pulmonary disease as controls. We selected muscular pulmonary arteries and calculated the percentage of the thickness of each layer of the wall (intima, media, and adventitia) in relation to the external diameter. We also quantified the percentage of areas of elastic fiber in the media divided by the whole area of the media (medial elastic fiber score). The percentage of adventitial thickness in IPPFE was significantly higher than that in IPF and in control lungs. The percentage of medial thickness did not differ statistically between IPPFE and IPF. However, the medial elastic fiber score in IPPFE was also significantly larger than that in IPF and control lungs. These results suggest that collagenous thickening of the adventitia and medial elastosis are distinct histological features in the muscular pulmonary arteries of patients with IPPFE.

Clinico-radiologic features of pleuroparenchymal fibroelastosis in children

BACKGROUND

Pleuroparenchymal fibroelastosis (PPFE) may be underdiagnosed clinically and radiographically in children with a remote history of cancer, leading to a delay in care and unnecessary lung biopsies.

OBJECTIVE

To describe the characteristic clinical and radiologic findings of PPFE in a cohort of children to facilitate recognition and noninvasive diagnosis.

MATERIALS AND METHODS

Clinical presentation, history of chemotherapy or radiation therapy, lung or bone marrow transplantation, and lung function testing and outcome were retrospectively extracted from the electronic medical records of eight children treated at our institution's pulmonary medicine clinic with histopathology confirmation of PPFE from 2008 to 2018. Two pediatric radiologists evaluated the chest imaging studies for the presence or absence of published radiologic findings of PPFE in adults, including platythorax, pneumothorax, upper lobe predominant pleural and septal thickening, and bronchiectasis. Platythorax indices were calculated from the normal chest CT exams of eight age- and gender-matched individuals obtained via the radiology search engine.

RESULTS

The mean presentation age was 12.9 years (range: 7-16 years). Seven of the eight had a history of chemotherapy and radiation therapy for cancer. Three of the eight had undergone bone marrow transplantation and none had undergone lung transplantation. The mean time between chemotherapy, radiation therapy, and/or bone marrow transplantation and the presentation of PPFE was 8.4 years (range: 5.6-12.1 years). Most of the patients presented with dyspnea (63%), cough (50%) and/or pneumothorax (38%). The mean percentage of predicted FEV1 (forced expiratory volume in one second) was 14.1 (range: 7.7-27.5). All eight patients demonstrated platythorax, bronchiectasis, pleural and septal thickening (upper lobes in four, upper and lower lobes in four) and six had pneumothorax. Five underwent lung biopsies, four of whom developed pneumothoraces.

CONCLUSION

Clinical and radiologic findings of pediatric PPFE are similar to those in adults, although a majority of the former have a history of treated cancer. Clinical presentation of restrictive lung disease, dyspnea, cough or spontaneous pneumothorax years after treatment for childhood cancer combined with platythorax, upper lobe pleural and septal thickening and traction bronchiectasis on chest CT establishes a presumptive diagnosis of PPFE.