[Lipid peroxidation in bronchoalveolar lavage fluid in interstitial lung diseases in relation to other components and...

We measured lipid peroxide (LPO) in bronchoalveolar lavage fluid (BALF) from patients with interstitial lung diseases (ILD, 45 cases) including sarcoidosis (22 cases) and idiopathic interstitial pneumonia (7 cases). LPO correlated negatively with the macrophage fraction, and positively with lymphocyte fraction, type III procollagen N terminal peptide (PIIIP), and total protein in all cases. In sarcoidosis, it correlated with PIIIP positively, and in IIP, with total cell count, macrophage count, PIIIP/protein and total protein. Comparison between the current smoker group (SM) and non-smoker group (NON/EX) showed that in all cases, SM had lower LPO, lymphocyte fraction, lymphocyte count and total protein whereas higher macrophage fraction than NON/EX. In sarcoidosis, SM had a lower lymphocyte fraction and total protein and higher macrophage fraction. We conclude that LPO in BALF reflects inflammation and fibrosis occurring in the lung with ILD and this process might be suppressed in smokers.