Fig. 1

Gut microbial dysbiosis in CPP patients. A The number of OTUs between CPP group and healthy control group. B The shared OTUs between CPP group (shown in red) and healthy controls (shown in blue) (CPP group with 2586 and healthy controls with 2266). C The correlation analysis between two groups at the OUTs level. The heatmap on left showed the Spearman correlation coefficients and the box plots showed the correlation coefficients within and across group comparisons. D The distribution of the Chao index between two groups, and the healthy controls presented a higher Chao index (using the Wilcox’s rank sum test to calculate p-values). E PCoA analysis was performed based on the Bray–Curtis distance between two groups and the significant differences between groups were calculated by ANOSIM. This figure presented the first principal component and the second principal component. F The distribution of Genus species in two groups. G The differential analysis of species between two groups at the genus level. H The differences in species abundance between groups at the genus level. I The performance assessment of the random forest model based on the training set, test set, and training–testing set (****p <  = 1.0E⁻⁴, ***p <  = 0.001, **p <  = 0.01, *p < 0.05)