Study Of Hysteroscopy Combined With Microecology As Auxiliary Tools In The Diagnosis Of Chronic Endometritis

Objective: This study sought to explore the value of hysteroscopy,intrauterine microbiota in the diagnosis of chronic endometritis,based on the analysis between histopathology,hysteroscopy,and intrauterine microbiota.Methods: Paired samples of endometrial biopsy and intrauterine fluid collected from the drainage port of hysteroscopy were obtained simultaneously from 142 cases enrolled in our study.These patients were recruited in conformity with the inclusion and exclusion criteria and underwent hysteroscopy at the First Affiliated Hospital of Xiamen University from October 2018 to February 2019,and the characteristic manifestations of the uterine cavity were recorded and analyzed.Endometrial tissues were made into histopathological sections using the CD138 immunohistochemistry staining method,while the 16 S ribosomal RNA gene extracted from intrauterine flora was sequenced under high-throughput sequencing.The histopathology results,defined as the "gold standard," were compared with hysteroscopy and sequencing outcomes to analyze the relationship among the three.Results:(1)The presence of focal hyperemia,diffuse hyperemia,micropolyps,and enlarged glandular openings on the endometrium are related factors of chronic endometritis.Endometrial punctate hyperemia,thickening,edematous,and vasodilation are independent factors affecting chronic endometritis.The accuracy of using a single sign under hysteroscopy for the diagnosis of chronic endometritis is less than 80%,whereas the combination of the features mentioned above,especially the combination of "1 or more independent factors + 0 or 1 or more related factors",can improve diagnostic accuracy notably.(2)The microorganisms in the uterine cavity chiefly comprise of Proteobacteria,Firmicutes,Bacteroides,Actinobacteria.Even though the species and relative abundance of intrauterine microorganisms vary significantly among individuals,they still own a certain regularity.The relative abundance of Firmicutes,especially Lactobacillus and Lactobacillus＿iners,is inversely correlated to some species in Proteobacteria,Bacteroides,and Actinobacteria.(3)Compared with the negative cases,the histopathologically positive cases had more Proteobacteria,Bacteroides,Actinobacteria,and relatively few Firmicutes,which is consistent with the regularity of the uterine flora,but the difference was not statistically significant(P>0.05).Burkholderia,Delftia,Sphingomonas,Burkholderia＿bryophila,Sphingomonas＿echinoides are characteristic species among Histopathological positive cases,and the diagnostic accuracy is between 50%-60%.(4)Compared with the controlled group,there are more species in the cases with specific manifestations,which are more evenly distributed,and own substantial differences in species types and distribution between samples.In contrast,the control group had dominant flora,fewer species,and high similarity in species types and distribution between samples.These differences between groups resemble those between the histopathological positive and negative groups.Some characteristic species are identical between groups that own different hysteroscopic features,while 14 of the 19 characteristic species in the histopathologically positive group can be found in these groups.(5)There showed no significant correlation between the pale endometrium and chronic endometritis(P> 0.05).The diagnostic accuracy of this single sign is 22.22%,Lactobacillus＿helveticus is its dominant species,and some characteristic species were the same as the histopathologically negative group.Conclusion:(1)Hysteroscopy is of great significance in the diagnosis of chronic endometritis,especially the combination of multiple hysteroscopic features can greatly improve the accuracy of diagnosis.From the perspective of the intrauterine flora,it can be confirmed that there is a correlation between hysteroscopic features and chronic endometritis,but they are not completely equivalent.(2)Neither the statistical analysis nor the intrauterine flora sequencing can prove that pale endometrium can be used as a hysteroscopic feature of chronic endometritis.(3)Lactobacillus in the uterine cavity of different individuals has an inverse relationship with some other species.(4)The disparity between the uterine flora of chronic endometritis and non-chronic endometritis is mainly reflected in the reduction of Lactobacillus and the increase of other species,however,no specific species with high diagnostic accuracy have been found.