Idiopathic pulmonary fibrosis (IPF) is a form of interstitial lung disease (ILD) characterized by subpleural fibrosis and fibroplasia in the usual interstitial pneumonia (UIP) pattern. According to a 2012 review, the estimated number of IPF cases per 100,000 population in the United States ranged from 14 to 27.9 when narrowly defined, and 42.7 to 63 when broadly defined.1 The estimated prevalence in Europe ranged from 1.25 to 23.4 cases per 100,000 population.
“Increasing evidence supports the concept of IPF as an age-related disease of alveolar epithelial cell dysfunction, and its management is distinct from other fibrotic ILDs that mimic it, in particular fibrotic hypersensitivity pneumonitis (HP),” according to a recent paper on the topic.2,3 This distinction highlights the importance of accurate diagnosis in cases of suspected IPF.
Bronchoalveolar lavage (BAL) “provides a fluid-based sampling of a lung subsegment’s small airways and alveoli, and the diagnostic value of the percentage of macrophages, neutrophils, lymphocytes, and eosinophils in BAL fluid has been studied for many decades,” with a particular focus on its value in differentiating fibrotic HP from IPF.4,5
In 2 editorials recently published in Chest, presented in a point-counterpoint format, one author expressed support for the routine use of BAL in IPF diagnosis, whereas the other disagreed with its routine use for this purpose.2,6 When crafting the 2011 guidelines for IPF diagnosis, the committee reviewed the evidence pertaining to such use and determined that it generally was not supported by the available data, as its added diagnostic value was unclear.7
To learn more about the reasons for these divergent views, Pulmonology Advisor interviewed Athol Wells, MD, a professor in the Interstitial Lung Disease Unit at Royal Brompton Hospital in London, United Kingdom; and Joshua Mooney, MD, MS, a clinical assistant professor of pulmonary and critical care medicine and director of the Pulmonary Fibrosis Foundation Care Center at Stanford University School of Medicine in California.
Dr Wells coauthored the paper supporting routine BAL use, whereas Dr Mooney coauthored the paper arguing against its routine use.
Pulmonology Advisor: Why is there debate regarding the routine use of BAL in the diagnostic evaluation of IPF?