Correlation Study Of Vaginal Microecological Changes After LEEP In High Cervical Intraepithelial Lesions

Objective: By analyzing changes in the microbiological composition of the vagina in patients with preoperative high grade intraepithelial lesions(HSIL)with high risk human papillomavirus(HR-HPV)positivity in the cervix and who were HPV negative after loop electrosurgery(LEEP),we explore the relationship between HR-HPV clearance and female vaginal microecology.This provides a new theoretical basis for the treatment,prevention and control of cervical cancer and HSIL.Methods: According to the inclusion and exclusion criteria,15 cases of women whose HR-HPV became negative after LEEP with HSIL were selected as the research subjects.The secretions and clinical data of the posterior vaginal vault of each patient were collected before LEEP and 3 to 4 months after the operation,and The samples were subjected to 16 S r RNA V3-V4 region gene amplification and high-throughput sequencing.Based on the sequencing results,changes in vaginal microbial composition were analyzed before and after surgery and the differences in vaginal microecological structure between the two were compared.Using bioinformatics methods,alpha diversity and beta diversity were analyzed to study the diversity and abundance of vaginal flora in the pre-and post-operative groups,and Wilcoxon differences were used to count the changes in the differences in vaginal microecological composition before and after surgery.Results: 1.Wayne’s analysis found that most of the OTU in the preoperative group and the postoperative group were common,and the number of OTU in the preoperative group was more than that in the postoperative group.It indicated that most of the microflora in the two groups were consistent,and the types of microflora in preoperative HSIL women were more than those in postoperative women.2.Compared with the preoperative group,postoperative Chao1,Shannon,Simpson and PD whole tree indexes of women were significantly decreased,indicating that the species diversity and richness of vaginal flora were significantly decreased after LEEP.3.The results of β-diversity analysis of vaginal microbiome showed that although the preoperative and postoperative vaginal microbiome structure of individual samples were similar,the overall microbiome structure was somewhat different.4.By analyzing the species composition at the phylum level,it was found that Bacteroidetes,Firmicutes,Actinobacteria and Proteobacteria were the dominant phyla in the vaginal microecology of the preoperative and postoperative groups.At the genus level,Lactobacillus,Bacteroidetes,Gardnerella and Prevotella were the dominant flora in the preoperative group,while Lactobacillus,Bacteroidetes,Gardnerella,Amycobacterium and Giganococcus were the dominant flora in the postoperative group.At the species level,the dominant bacteria in the preoperative group were inertlactobacillus,streptococcus,chlamydia,cilium,etc.,while the dominant bacteria in the postoperative group were inert-lactobacillus,lactobacillus garneri,streptococcus,bifidobacterium,etc.5.Wilcoxon ranksum test showed that at the genus level,the proportion of Lactobacillus in the postoperative group was significantly increased(P=0.003),while the proportion of Prevotella,Ciliocilia,Rothella and Giganococcus was significantly decreased(P < 0.05).The proportion of Gardnella was also decreased after the surgery,but the difference was not statistically significant(P=0.0529).At the species level,the proportions of inert Lactobacillus and Lactobacillus garnesii in the postoperative group were significantly increased(P<0.05),the proportions of Prevotella,Bacteroidetes and Chlamydia were significantly decreased(P<0.05),and the proportion of Bacillus in the postoperative group also showed a decreasing trend,but the difference was not statistically significant(P =0.0629).Conclusion: 1.The vaginal microecological diversity of HSIL women was relatively complex.After LEEP,HPV turned negative,the vaginal microecological diversity decreased,and the pathogenic bacteria related to bacterial vaginitis,such as Gardnerella and Prevotella,decreased.2.In HSIL women,the proportion of Lactobacilli canadei and Lactobacilli inertia increased after HPV conversion after LEEP,and the microflora showed a tendency to change to the vaginal flora of healthy women.It is suggested that Lactobacillus garneri and lactic acid bacteria are the protective bacteria to the cervix,which may promote the clearance of HPV.