The level of MDA in BALF might reflect oxidative tissue damage in patients with mild MAC pulmonary disease

Background: The prevalence of non-tuberculous mycobacterial (NTM) pulmonary disease is globally increasing. The most common pathogen isolated in Japan is the Mycobacterium avium complex (MAC), and the natural history of MAC pulmonary disease (MAC-PD) remains unclear, even in mild cases of MAC-PD. Our previous study showed that serum dROM (oxidative stress marker) as well as the increase of total cell counts and neutrophil percentages in bronchoalveolar lavage fluid (BALF) were related to the commencement of chemotherapy (CT). Aims: To elucidate whether the level of oxidative stress in BALF reflect the disease severity and can be a marker for initiating CT in mild cases of MAC-PD. Methods: Between June 2016 and March 2019, 34 subjects who were suspected of MAC-PD and underwent diagnostic bronchoscopy were included, and all of patients did not show systemic inflammation. According to the findings of bronchoscopy, subjects were divided into MAC group and Non-MAC group. MAC group were subdivided into Treatment group (MAC-T) and Observation group (MAC-O). We measured malondialdehyde (MDA) in BALF and serum d-ROM as a marker of oxidative stress. Results: Total cell counts as well as neutrophil percentages in BALF were the highest in MAC-T group among three groups (P Conclusions: The level of MDA in BALF seemed to reflect the oxidative tissue damage in mild cases of MAC-PD, and it might be an indicator for disease severity and the commencement of CT.