Characterisation of gut microbiota composition in patients with axial spondyloarthritis and its modulation by TNF inhibitor treatment.

Several SpA patients' characteristics modulate the composition of gut microbiota as did TNFi treatment. Moreover, the abundance/prevalence of seven OTUs at baseline may be used as a novel non-invasive index that predicts the response to TNFi with greater accuracy than HLA-B27 status, CRP level and measures of disease activity.