Role of Bacterial Contamination in Endometriosis

Khaleque Newaz Khan, Michio Kitajima, Akira Fujishita, Masahiro Nakashima, Hideaki Masuzaki, Jo Kitawaki
In: Journal of Endometriosis and Pelvic Pain Disorders · 2015 · vol. 8(1) , pp. 2–7 · doi:10.5301/je.5000229 · W2250528192
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This review assesses the bacterial contamination hypothesis in endometriosis, finding increased intrauterine microbes and E. coli LPS stimulating proinflammation and endometrial cell growth via TLR4, with GnRHa treatment exacerbating colonization.

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Abstract

The human lower genital tract is constantly exposed to various microorganisms, which can infect the upper genital tract through ascending migration. We report on tests of the hypothesis that as normal microbial flora in the vagina, some gram-negative bacteria infect the uterine wall after ascending migration from the vagina, to contaminate menstrual blood, consequently resulting in accumulation of endotoxin in the menstrual/peritoneal fluid and initiation of pelvic inflammation. The aim of the present review is to assess possible intrauterine microbial colonization and to examine the stimulatory effect of E. coli-derived lipopolysaccharide (LPS) on the secretion of various macromolecules by macrophages (Mϕ) known to be involved in endometriosis. We also assess the growth-promoting effect of LPS on endometrial cells and the role of Toll-like receptor 4 (TLR4), a receptor recognizing LPS, in the secretion of macromolecules by Mϕ and growth of endometrial cells. We found higher intrauterine microbial colonization in women with endometriosis than in controls. The ligand from gram-negative bacteria is involved in TLR4-mediated proinflammation in the pelvis as well as growth of endometriosis. Treatment with gonadotropin-releasing hormone agonist (GnRHa) further promotes intrauterine microbial colonization compared with GnRHa-untreated women. Conclusions We propose the bacterial contamination hypothesis as a new concept in endometriosis. Based on our current findings, an estrogen-suppressing agent and an antimicrobial agent may have new therapeutic potential in women with endometriosis.

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endometriosis

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Papers in the corpus that this work cites (lower rings, blue) and that cite this one (upper rings, green). Dot size scales with the paper's in-corpus citation count — bigger dot = more influential within the endo/adeno field. Click a dot to open that paper. [ expand to 2 hops ] — adds papers reached through this work's immediate citers/citees. Heavier; up to 60 extra dots.

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