The effect of surgical fecal stream diversion of the healthy colon on the colonic microbiota

Outcome measures reported following feminizing genital gender affirmation surgery for transgender women and gender diverse individuals: A systematic review

Background

Feminizing genital gender affirmation surgery (fgGAS) may be an essential adjunct in the care of some transgender women and gender diverse individuals with gender incongruence. However, the comparison of different techniques of fgGAS may be confounded by variable outcome reporting and the use of inconsistent outcomes in the literature. This systematic review provides the most in-depth examination of fgGAS studies to date, and summarizes all reported outcomes, definitions, and the times when outcomes were assessed following these surgical interventions. Aims/Methods: This work intends to quantify the levels of outcome variability and definition heterogeneity in this expanding field and provides guidance on outcome reporting for future study authors. Candidate studies for this systematic review were sourced via an electronic, multi-database literature search. All primary, clinical research studies of fgGAS were included with no date limits. Paired collaborators screened each study for inclusion and performed data extraction to document the outcomes, definitions, and times of outcome assessment following fgGAS.

Results

After screening 1225 studies, 93 studies proceeded to data extraction, representing 7681 patients. 2621 separate individual outcomes were reported, 857 (32.7%) were defined, and the time of outcome assessment was given for 1856 outcomes (70.8%) but relied on nonspecific ranges of follow-up dates. "Attainment of orgasm", "Neovaginal stenosis", and "Neovaginal depth/length" were among the most commonly reported outcomes. Profound heterogeneity existed in the definitions used for these and for all outcomes reported in general.

Discussion

The results demonstrate a need for clear outcomes, agreed definitions, and times of outcome assessment following fgGAS in transgender women and gender diverse individuals. The adoption of a consistent set of outcomes and definitions reported by all future studies of fgGAS (a Core Outcome Set) will aid in improving treatment comparisons in this patient group. This review is the first step in that process.

Microbial Associations With Microscopic Colitis

INTRODUCTION

Microscopic colitis is a relatively common cause of chronic diarrhea and may be linked to luminal factors. Given the essential role of the microbiome in human gut health, analysis of microbiome changes associated with microscopic colitis could provide insights into the development of the disease.

METHODS

We enrolled patients who underwent colonoscopy for diarrhea. An experienced pathologist classified patients as having microscopic colitis (n = 52) or controls (n = 153). Research biopsies were taken from the ascending (ASC) and descending (DES) colon, and the microbiome was characterized with Illumina sequencing. We analyzed the associations between microscopic colitis and microbiome with a series of increasingly complex models adjusted for a range of demographic and health factors.

RESULTS

We found that alpha diversity was significantly lower in cases with microscopic colitis compared with that in controls in the DES colon microbiome. In the DES colon, a series of models that adjusted for an increasing number of covariates found taxa significantly associated with microscopic colitis, including Proteobacteria that was enriched in cases and Collinsella that was enriched in controls. While the alpha diversity and taxa were not significantly associated with microscopic colitis in the ASC colon microbiome, the inference P values based on ASC and DES microbiomes were highly correlated.

DISCUSSION

Our study demonstrates an altered microbiome in cases with microscopic colitis compared with that in controls. Because both the cases and controls experienced diarrhea, we have identified candidate taxa that could be mechanistically responsible for the development of microscopic colitis independent of changes to the microbial community caused by diarrhea.

Systematic Review: The Neovaginal Microbiome

OBJECTIVE

To review neovaginal colonization and inflammatory patterns, and factors that may impact this.

METHODS

A systematic review of the neovaginal microbiome was conducted in concordance with PRISMA guidelines through October 2021.

RESULTS

Thirteen articles were included, totaling 458 patients. Neovaginal constructions were most commonly performed with penile and scrotal skin grafts, sigmoid segments, and peritoneal grafts. The neovaginal microflora identified were generally polymicrobial and shared similarities with the native tissue. Nine studies identified Lactobacillus: 5/6 for penile skin, 1/3 for sigmoid, 1/1 for peritoneum, and 2/3 for other graft types, suggesting that the neovagina may support Lactobacillus either innately, via rectal migration or oral probiotic supplementation. A polymicrobial, bacterial vaginosis-like environment was found in nine studies. Inflammatory markers were also described: 2/6 for penile skin, 2/3 for sigmoid, 0/1 for peritoneum, and 1/3 for other graft types. Scant data were available on the impact of postsurgical duration, oral hormones, dilating, sexual practices, or douching on the neovaginal microbiome.

CONCLUSION

Understanding and optimizing the polymicrobial neovaginal microenvironment may improve surgical outcomes, specifically inflammatory, pain, and infectious. Future research should focus on standardizing testing and classification systems, and treating neovaginal dysbiosis.