ESR1 and SAPHO syndrome: These results suggest that the abundance changes of certain dominant bacteria may lead to changes in clinical indicators in patients with SAPHO syndrome, which can be used as biomarkers of clinical improvement; however, there are still some other dominant bacteria that do not show different distribution, for example, Alistipes and Prevotella 9, which are positively correlated with ESR, hsCRP and VAS, and enriched in the HC samples.