Positive fungal quantitative PCR and Th17 cytokine detection in bronchoalveolar lavage fluids: Complementary biomarkers of hypersensitivity pneumonitis?

Background: Interstitial lung disease (ILD) is a large group of diseases, including hypersensitivity pneumonitis (HP), idiopathic pulmonary fibrosis (IPF) and sarcoidosis.

Objective: In this study, we aimed to identify bronchoalveolar lavage fluid (BALF) biomarkers which could be contributive for HP diagnosis.

Methods: We analyzed 39 BALF samples from 12 ILD patients with sarcoidosis, 11 with IPF and 16 with HP. We determined the levels of 10 cytokines and carried out quantitative PCR for 10 microorganisms involved in farm-associated or domestic forms of HP.

Results: IL-8, IL-6, TNFα, IL-17 and IL-23 levels were significantly higher in BALF samples from HP patients (p<0.05, one-way Kruskal-Wallis analysis). QPCR tests for Eurotium amstelodami and Wallemia sebi were positively significantly more frequently for HP patients (p<0.05, one-way Kruskal-Wallis).

Conclusion: The biomarkers identified here can be detected in BALF, which could be routinely obtained as complementary analysis in ILD diagnosis.