Fig. 1

BAL microbiota richness and diversity. Alpha diversity was calculated using number of OTUs (a), Simpson diversity index (b), and the Faith’s phylodiversity index (c), all revealing significant differences between healthy subjects and sarcoid or RA. No significant differences were found between both patient groups. Beta diversity (d) demonstrated that RA and sarcoid samples clustered together and away from healthy controls. **P < 0.01; ***P < 0.001; ****P < 0.0001; ns non-significant