Manasson J, et al. - The gut microbiota and host gene interactions in reactive arthritis (ReA) and post-infectious spondyloarthritis are described in this study. This is the first culture-independent study describing the gut microbial community of post-infectious arthritis. Albeit bacterial factors correlated with disease presence and clinical features of ReA, host genetics also appeared to be a major independent driver of intestinal community composition. Comprehension of these gut microbiota host-genetic relationships may further clarify the pathogenesis of post-infectious spondyloarthropathies.