Investigation of the Female Genital Tract Microbiome and its Association
with Hydrosalpinx in Women Undergoing Salpingectomy.
Abstract
Objective: To describe the microbiome of the vagina and fallopian tubes,
and its relation with hydrosalpinx. Design: Prospective case-control
study. Population and Settings: Women who underwent salpingectomy for
hydrosalpinx or other indications at our medical center . Main Outcome
Measures: Samples obtained during surgery and were subjected to 16S rRNA
amplicon sequencing, and analyses of alpha diversity and beta diversity
meseaures were compared between sites and groups. Differential
abundances of bacteria associated with vaginal dysbiosis was compared
between cases and controls. Results: Nine women with hydrosalipnx, and
23 women without hydrosalpinx were included in the study. The mean age
of studied women was 41 (range: 29-54), and most (89%) were
premenopausal. After in silico decontamination, only 30% of control
fallopian tubes samples, and 10% of case fallopian tubes samples, had
evidence of bacterial presence. The vaginal microbiota of control
patients showed greater abundance of lactobacilli whereas the vaginal
microbiome of case patients contained relatively more bacterial
vaginosis associated bacteria such as Prevotella,
Gardenrella and Atopobium. A significant difference was
found in alpha and beta diversity between the vaginal and FT microbiomes
in control patients, as fallopian tubes samples were more diverse. We
found that women with hydrosalpinx had a more “dysbiotic” vaginal
microbiome, and in women without hydrosalpinx, microbial composition
within the vagina and FT differed, possibly representing two distinct
ecological environments. Conclusion: women undergoing salpingectomy for
various reasons harbored bacteria within their FT, women with
hydrosalpinx generally did not. This suggests that even though infection
may be an underlying cause of hydrosalpinx, bacteria may not be present
by the time patients require surgery.