Usually sub-pleural and characterized by well-defined walls and disposed in at least two lines. Generally one line of cysts is not sufficient to define honeycombing
Ground-glass opacities are common but less extensive than the reticulation
Distribution characteristically basal and peripheral though often patchy. Histology
According to the updated 2011 guidelines, in the absence of a typical UIP pattern on HRCT, a surgical lung biopsy is required for confident diagnosis.Histologic specimens for the diagnosis of IPF must be taken at least in three different places and be large enough that the pathologist can comment on the underlying lung architecture. Small biopsies, such as those obtained via transbronchial lung biopsy (performed during bronchoscopy) are usually not sufficient for this purpose. Hence, larger biopsies obtained surgically via a thoracotomy or thoracoscopy are usually necessary.Lung tissue from people with IPF usually show a characteristic histopathologic UIP pattern and is therefore the pathologic counterpart of IPF. Although a pathologic diagnosis of UIP often corresponds to a clinical diagnosis of IPF, a UIP histologic pattern can be seen in other diseases as well, and fibrosis of known origin (rheumatic diseases for example). There are four key features of UIP including interstitial fibrosis in a patchwork pattern, interstitial scarring, honeycomb changes and fibroblast foci.Fibroblastic foci are dense collections of myofibroblasts and scar tissue and, together with honeycombing, are the main pathological findings that allow a diagnosis of UIP. Bronchoalveolar lavage
Bronchoalveolar lavage (BAL) is a well-tolerated diagnostic procedure in ILD.
Follow-up
IPF is often misdiagnosed, at least until physiological and/or imaging data suggest the presence of an ILD leading to delay in accessing appropriate care. Considering that IPF is a disease with a median survival of three years after diagnosis, early referral to a center with specific expertise should therefore be considered for any patient with suspected or known ILD. On the basis of the complex differential diagnostic, multidisciplinary discussion between pulmonologists, radiologists, and pathologists experienced in the diagnosis of ILD is of the utmost importance to an accurate diagnosis.Those with IPF have higher chances of getting lung cancer, at a rate of 13.5% where the most common cancer type is Squamous-cell carcinoma of the lung. a routine evaluation every 3 to 6 months, including spirometry (body plethysmography), diffusion capacity testing, chest X-rays, 6MWT, assessment of dyspnea, quality of life, oxygen requirement is mandatory.In addition, the increasing awareness of complications and common concomitant conditions frequently associated with IPF requires a routinely evaluation of comorbidities, most of them simply reflecting concurrent diseases of aging, and medications with their interaction and side effects. Acute exacerbations
Acute exacerbations of IPF (AE-IPF) are defined as an unexplained worsening or development of dyspnea within 30 days with new radiological infiltrates at HRCT abnormality often superimposed on a background consistent with UIP pattern. The yearly incidence of AE-IPF is between 10 and 15% of all patients. The prognosis of AE-IPF is poor, with mortality ranging from 78% to 96%.