Idiopathic interstitial pneumonias: review of the latest American Thoracic Society/European Respiratory Society classification

Abstract

The diagnosis of idiopathic interstitial pneumonias (IIPs) involves a multidisciplinary scenario in which the radiologist assumes a key role. The latest (2013) update of the IIP classification by the American Thoracic Society/European Respiratory Society proposed some important changes to the original classification of 2002. The novelties include the addition of a new disease (idiopathic pleuroparenchymal fibroelastosis) and the subdivision of the IIPs into four main groups: chronic fibrosing IIPs (idiopathic pulmonary fibrosis and nonspecific interstitial pneumonia); smoking-related IIPs (desquamative interstitial pneumonia and respiratory bronchiolitis-associated interstitial lung disease); acute or subacute IIPs (cryptogenic organizing pneumonia and acute interstitial pneumonia); rare IIPs (lymphoid interstitial pneumonia and idiopathic pleuroparenchymal fibroelastosis); and the so-called “unclassifiable” IIPs. In this study, we review the main clinical, tomographic, and pathological characteristics of each IIP.

Treatment of Rheumatoid Arthritis-Associated Interstitial Lung Disease: Lights and Shadows

“…However, the real incidence of RA-related ILD (RA-ILD) is still unknown, and a variable prevalence has been reported in the literature [5][6][7][8]. The usual interstitial pneumonia (UIP) is the predominant histological/radiological pattern of RA-ILD, reported in up to 66% of cases [9][10][11][12][13][14][15][16][17][18][19] ( Table 2). ILD can occur at any point in the natural history of RA, sometimes before the appearance of joint involvement [14,20,21].…”

“…Table 2. Histologic classification and typical features of idiopathic interstitial pneumonia,.applicable to rheumatoid arthritis RA-ILD interstitial lung disease [9][10][11][12][13][14][15][16][17][18][19]. Moreover, in patients with non-symptomatic RA-ILD, a clinical, functional and radiologic follow-up of the lung is mandatory to identify patients with progressive disease.…”

Clinical and Functional Characteristics of Patients with Unclassifiable Interstitial Lung Disease (uILD): Long-Term Follow-Up Data from European IPF Registry (eurIPFreg)

“…Of them, idiopathic pulmonary fibrosis (IPF) is associated with the highest burden and poor prognosis [5][6][7]. Apart from IPF, other IIPs include idiopathic non-specific interstitial pneumonia (NSIP), respiratory bronchiolitis-ILD (RB-ILD), desquamative interstitial pneumonia (DIP), cryptogenic organizing pneumonia (COP), acute interstitial pneumonia (AIP), and some other rare forms [8,9].…”

Idiopathic Interstitial Pneumonias and COVID-19 Pneumonia: Review of the Main Radiological Features and Differential Diagnosis

“…• clear demarcation between healthy pulmonary parenchyma and affected pulmonary parenchyma (IPF/UIP) [5,32] (Figure 3a); • coexistence of other radiological findings as centrilobular nodules (RB-ILD, OP) and thin-walled cysts (LIP) [35,38] (Figures 4a, 5a-c and 6a); • presence of fibrosis that may be appreciated as parenchymal distortion, traction bronchiectases and/or honeycombing (IPF/UIP, NSIP, OP, late-stage AIP, PPFE) [5,18,54,61] (Figure 3, Figure 5a-c,e and Figure 6b); • pleural thickening (PPFE) [5,32,61] (Figure 6b); • pleural effusions (exudative AIP, OP) [5] (Figure 5a-d).…”