Colonization of the upper genital tract by vaginal bacterial species in nonpregnant women

Abstract

Objective Evaluate upper genital tract (UGT) presence of vaginal bacterial species using sensitive molecular methods capable of detecting fastidious bacterial vaginosis (BV)-associated bacteria. Study Design Vaginal swabs were collected prior to hysterectomy. The excised uterus was sterilely opened and swabs collected from endometrium and upper endocervix. DNA was tested in 11 quantitative PCR (qPCR) assays for 12 bacterial species: Lactobacillus iners, L. crispatus, L. jensenii, Gardnerella vaginalis, Atopobium vaginae, Megasphaera spp., Prevotella spp., Leptotrichia/Sneathia, BVAB1, BVAB2, BVAB3 and a broad-range16S rRNA gene assay. Endometrial fluid was tested with Luminex and ELISA for cytokines and defensins, and tissue for gene expression of defensins and cathelicidin. Results We enrolled 58 women: mean age 43 + 7 years, mostly white (n = 46; 79%) and BV-negative (n = 43; 74%). By species-specific qPCR, 55 (95%) had UGT colonization with at least one species (n = 52), or were positive by 16S PCR (n = 3). The most common species were L. iners (45% UGT, 61% vagina), Prevotella spp. (33% UGT, 76% vagina) and L. crispatus (33% UGT, 56% vagina). Median quantities of bacteria in the UGT were lower than vaginal levels by 2–4 log10 rRNA gene copies/swab. There were no differences in endometrial inflammatory markers between women with no bacteria, Lactobacillus only or any BV-associated species in the UGT. Conclusion Our data suggest that the endometrial cavity is not sterile in most women undergoing hysterectomy, and that the presence of low levels of bacteria in the uterus is not associated with significant inflammation.

Human Three-Dimensional Endometrial Epithelial Cell Model To Study Host Interactions with Vaginal Bacteria and Neisseria gonorrhoeae

“…5). These results are in accordance with those of a study by Mitchell and colleagues, who observed the presence of vaginal bacterial species in the endometrial cavities of most women undergoing a hysterectomy (18). These investigators also tested endometrial fluid and tissue for cytokines and defensins and showed that colonization of the upper FRT with low levels of vaginal species is not associated with increased levels of inflammatory markers.…”

“…Previous reports have shown that vaginal microbiota are able to ascend to the upper FRT and invade the endometrium (18,19,33). To study host-microbe interactions in our human 3-D EEC model, we infected EEC aggregates with commensal and pathogenic vaginal bacteria, namely, L. crispatus strain VPI-3199, G. vaginalis strain JCP8066, Mobiluncus mulieris strain UPII 28-I, or N. gonorrhoeae MS11.…”

“…For these studies, we selected bacterial species commonly found in the human FRT, including a sexually transmitted pathogen, N. gonorrhoeae, and two endogenous vaginal microbes, one of which (L. crispatus) is commensal and the other of which (G. vaginalis) is associated with BV (18,19,33,55). It should also be noted that both N. gonorrhoeae and G. vaginalis are associated with endometritis and PID (2,20,21,55,56).…”

“…Mitchell et al tested for the presence of vaginal bacterial species, including commensal lactobacilli (i.e., Lactobacillus crispatus, Lactobacillus iners, and Lactobacillus jensenii) and BV-associated bacteria (Gardnerella vaginalis, Atopobium vaginae, Megasphaera spp., Prevotella spp., Leptotrichia/Sneathia spp., BVAB1, BVAB2, and BVAB3), in endometrial samples collected from patients undergoing hysterectomy using quantitative PCR assays (18). The study revealed that uteri from 90% of enrolled patients were colonized with at least one vaginal species.…”

The role of bacterial biofilms in the development of chronic pathological processes in the vagina and endometrium

“…Патологические про-цессы в эндометрии могут развиться только при высокой концентрации бактерий в полости матки, в присутствии смешанной бактериаль-ной микрофлоры и при наличии вирулентных штаммов. Таким образом, эти данные указыва-ют на то, что полость матки не является сте-рильной у большинства женщин, перенесших гистерэктомию по поводу доброкачественных новообразований [53]. W.W. Andrews и др.…”