Interstitial lung abnormalities: erecting fences in the path towards advanced pulmonary fibrosis

Abstract

Interstitial lung abnormalities, when present in members of undiagnosed family members recruited on the basis of familial interstitial pneumonia, or in undiagnosed research participants, have been associated with a syndrome that includes distinct sets of imaging abnormalities, restrictive physiological and exercise impairments, and an increased prevalence of histopathological findings, and genetic predictors, that have been noted in patients with idiopathic pulmonary fibrosis. Recent longitudinal studies have demonstrated that qualitative and quantitative assessments of interstitial abnormalities are associated with accelerated lung function decline, an increased rate of clinical diagnoses of interstitial lung disease and an increased rate of mortality. In this perspective, in addition to reviewing the prior information, four major efforts that could help the field of early pulmonary fibrosis detection move forward are discussed. These efforts include: (1) developing standards for characterising and reporting imaging findings from patients with existing CTs; (2) developing consensus statements on when undiagnosed and asymptomatic imaging abnormalities should be considered a disease; (3) identifying populations for which screening efforts might be beneficial; and (4) considering approaches to developing effective secondary prevention trials.

Keywords: ARDS; clinical epidemiology; idiopathic pulmonary fibrosis; imaging/CT MRI etc; interstitial fibrosis.

Figure 1

The figure (adapted from Ley et al (2011)[56]) includes a speculative representation of how idiopathic pulmonary fibrosis (IPF) progression might occur from those with an early stage of pulmonary fibrosis (PF) or subclinical disease (left panel). An updated and expanded representation of current knowledge (right panel) which highlights the under-recognised burden of early PF, the risk for accelerated lung function decline and early death even among those not diagnosed with IPF. IIP, idiopathic interstitial pneumonia; ILA, interstitial lung abnormalities.