Fig. 7

Alterations of oral microbiota in posttreatment stable SLE. A Rarefaction analysis between the number of samples and the number of OTUs. As the number of samples increased, the number of OTUs approached saturation in both groups, and the number of OTUs was significantly increased in SLE (n = 73) versus HC (n = 146). As measured by the Shannon index, the oral microbial diversity was significantly increased in SLE (n = 73) versus HC (n = 146) (p < 0.01). B The PCoA of oral microbial community for posttreatment stable SLE (n = 73) and HC (n = 146) in the unweighted Unifrac plot from PC1, PC2 and PC3 (33.61%, 22.84% and 13.2%). C Compared with HC, 21 genera were significantly increased, and 21 genera were significantly decreased in posttreatment stable SLE. D The average composition and relative abundance of the bacterial community in the posttreatment stable SLE (n = 73) and HC (n = 146) at the genus level. E Heatmap of the relative abundances of differential OTUs for each sample in the posttreatment stable SLE (n = 73) and HC (n = 146). The heatmap showed that 22 OTUs were enriched in SLE, and 28 OTUs were enriched in HC. F Nine OTUs were selected as the optimal markers set random forest model. G The POD value was significantly higher in SLE (n = 73) compared with that in HC (n = 146). H The POD value achieved an AUC of 0.9942 (95% CI 0.9884–1) between the posttreatment stable SLE (n = 73) and HC (n = 146) (p < 0.0001). HC healthy controls; stable, posttreatment stable SLE; OUT operational taxonomic unit; CV Error the cross-validation error, POD probability of disease, CI confidence interval, AUC area under the curve