PhD Scientific Days 2022

Clinical Medicine VII. (Poster discussion will take place in the Aula during the Coffee Break)

BAL in interstitial lung disease: differences according HRCT pattern

Text of the abstract

Rationale: Bronchoalveolar lavage (BAL) is an important tool in the diagnosis of interstitial lung diseases (ILD) for identification of pathogens, and cellular distribution often helping in the diagnostic workflow. The aim of our study was to evaluate BAL cellular distribution, respiratory function and HRCT pattern in progressive forms of ILDs including CTD-ILD, IPAF and IPF.
Methods: In our study all CTD-ILD, IPAF and IPF patients diagnosed between 2015 and 2021 at the Department of Pulmonology, Semmelweis University who had at baseline BAL were included (N=61). ILD diagnosis was always set by the multidisciplinary team. Pulmonary symptoms, lung function and BAL were analyzed in a cross sectional study.
Results: Patients were divided into two groups according HRCT pattern (Group 1 UIP-ILD, N=43, 51% males, mean age 63.8, IQR 18 years, Group 2 Non UIP-ILD N=18, 33% males, mean age 64.8, IQR 15.5 years). The most common symptoms were dyspnea (90%) and crackles (78%). There was a significant difference between the two groups in terms of joint pain, weight loss, crepitation, and Raynaud’s phenomenon. Lung function showed restrictive ventilator pattern regarding all cases (FVC% 76, IQR 76.9, TLC% 68.6, IQR 25.9, DLCO%, 67.6 IQR 30.5). BAL macrophages (Mac) were decreased, while inflammatory cells increased BAL for all patients (Neu: 16±17 %, Ly: 7±9 %, Eos: 5±10%, Mac: 68±22%, Ly/Neu 0.9±1). No difference was found between the 2 groups in respiratory function and BAL composition. In Group 1, patients with lower lymphocyte cell count had better DLCO (%) values (r2=0.1), and a similar negative correlation was found between TLC (%) and neutrophils in this group (r2=0.3) as compared to Group 2, where there was only a weak negative correlation between FVC (%) and lymphocyte cell counts (r=0.1).
Conclusion: In patients with UIP pattern lower BAL lymphocyte count is associated with better lung function. Further analysis is needed to assess longitudinal functional decline according BAL findings.