In about half of the cases, PPFE is seen in the upper lung area and the usual interstitial pneumonia pattern is simultaneously seen in the lower lung area.
(32) Histologically, apical cap fibrosis is barely distinguishable from PPFE. (33) It may occur after pneumothorax, in which case it is often accompanied by emphysematous changes.
Idiopathic PPFE also needs to be differentiated from idiopathic pulmonary fibrosis (IPF).
PPFE is a rare condition and characterized by fibroelastic thickening in the pleura and subpleural lung parenchyma especially in the upper lobes.
The less invasive procedures should be preferred for diagnosis of PPFE which is classified in IIP group so possible complication can be prevented.
Three patients underwent surgical lung biopsy and fulfilled the histological criteria for PPFE. In contrast, we identified 67 IPF patients who met the ATS/ERS/JRS/ALAT criteria ; of these, eight patients underwent surgical lung biopsy and fulfilled the histological criteria for IPF.
As per our knowledge, there was only one prognostic article, which stated that the survival time of patients with PPFE with UIP pattern tended to be shorter than that of patients with IPF/UIP .
In terms of physical findings, (9) patients with PPFE are often slender, and a "flattened thoracic cage" may be present.
(9) In addition, interstitial lung disease patterns can be appreciated in the other parts of the lung, such as the lower lobes, and the patterns described include usual interstitial pneumonia (UIP) pattern, nonspecific interstitial pneumonia (NSIP) pattern, diffuse PPFE, and others.
When this occurs, the appearance is deceptively similar to pulmonary apical cap (PAC) and, by extension, pleuroparenchymal fibroelastosis (PPFE
), and UIP may be misdiagnosed as the latter.
The expected updated categorization outlined in Table 4 is similar to that in the 2002 international multidisciplinary consensus classification, (3) with the notable addition of idiopathic PPFE. This entity will be discussed further below.
Idiopathic PPFE was first mentioned in the English-language medical literature in 2004 in a small case series.