The colonized microbiota composition in the peritoneal fluid in women with endometriosis

Purpose The imbalance of microbiome in vivo is believed to be involved in the pathogenicity of endometriosis. This study aimed to investigate and analyze the composition of bacterial communities in the peritoneal fluid of women with endometriosis. Methods To collect peritoneal fluid samples from women with ( N = 36) and without ( N = 25) endometriosis in a generalized hospital in Hunan, China during January to December of 2019. Genomic DNA was extracted from peritoneal fluid samples, and targeted amplified for the V4 region of 16S ribosomal RNA gene followed by amplicon sequencing. Non-parametric Wilcoxon rank-sum test and chi‐squared test were used to compare and analysis the difference between groups. Results Analysis showed that microbiota diversity was similar in the peritoneal fluid of women with or without endometriosis. Ralstonia mainly dominated in the peritoneal fluid of patients in both groups, with an overall relative abundance of 11.15% (95% CI: 10.51–11.80%) in endometriosis patients, followed by Acinetobacter , Pseudomonas , Asticcacaulis , and Methyloversatilis, with no significant difference between endometriosis patients and the control group. Nevertheless, there were microbes with different abundance in peritoneal fluid of the two groups, and the relative abundance was less than 0.5%. Acidovorax ( P = 0.01), Devosia ( P = 0.03), Methylobacterium ( P = 0.03), Phascolarctobacterium ( P = 0.03), and Streptococcus ( P = 0.04) were more abundant in the peritoneal fluid of endometriosis patients than the controls, while Brevundimonas ( P = 0.01) and Stenotrophomonas ( P = 0.04) were less abundant. Conclusion The composition of minority microbiota including Acidovorax , Devosia , Methylobacterium , Phascolarctobacterium , and Streptococcus in peritoneal fluid were found to change among women with endometriosis. Further research is needed to explore the mechanisms of these microorganisms in the pathophysiology of endometriosis.