Consistent evidence on the detrimental role of severe chronic endometritis on in vitro fertilization outcome and the reproductive improvement after antibiotic therapy: on the other hand, mild chronic endometritis appears a more intricate matter

Correlation between hysteroscopic features and specific microbial species in women with chronic endometritis

Objective and rationale

Chronic endometritis (CE) has recently been associated with unexplained infertility and recurrent miscarriages. The current gold standard for CE detection is histopathological examination. However, office hysteroscopy and endometrial cultures are also significant, due to the possible link between CE and various microorganisms. Bacterial colonization of the endometrium has been associated with reduced success rates of in vitro fertilisation embryo transfer. Few studies have tried to correlate CE hysteroscopy findings with pathogenic microorganisms. This prospective cohort study sought to establish whether hysteroscopic diagnostic lesions correlate with specific microbial species.

Methods

The study encompassed women undergoing diagnostic tests for a range of subfertility health issues. 189 women completed the standard office diagnostic hysteroscopy (DH). 181 had also endometrial samples taken for microbial culture investigation. Correlation analysis (χ2 and Fisher's exact test) between hysteroscopic findings suggestive of CE and endometrial cultures was carried out. Logistic regression models were also fitted to measure whether a positive endometrial culture could affect CE conditions.

Results

A significant association of E. coli was observed between the hysteroscopically characterized CE + group with focal hyperplasia, when compared to the non-CE group. Logistic regression analysis revealed that women positive for E. coli were 4.423 times more likely to have focal endometrial hyperplasia. No other significant correlations were identified between DH and positive endometrial cultures.

Conclusions

The presence of E. coli in the endometrium was significantly correlated with focal hyperplasia findings from hysteroscopy, emphasizing the importance of microbial cultures in the diagnosis and targeted treatment of CE in women with subfertility.

Chronic Endometritis in Infertile Women: Impact of Untreated Disease, Plasma Cell Count and Antibiotic Therapy on IVF Outcome-A Systematic Review and Meta-Analysis

This systematic review and meta-analysis aims to evaluate the impact of chronic endometritis (CE) and its therapy on in vitro fertilization (IVF) outcome. Additionally, we aim to investigate whether various degrees of CE severity may exert a different effect on IVF outcome. Ongoing-pregnancy rate/live-birth-rate (OPR/LBR), clinical-pregnancy rate (CPR), and miscarriage rate (MR) were calculated. A total number of 4145 patients (from ten studies) were included. Women with CE had lower OPR/LBR (OR 1.97, p = 0.02) and CPR (OR 2.28, p = 0.002) compared to those without CE. CE cure increased OPR/LBR (OR 5.33, p < 0.0001) and CPR (OR 3.64, p = 0.0001). IVF outcome was comparable between women with cured CE and those without CE (OPR/LBR, CPR and MR: p = ns). Women with severe CE had lower OPR/LBR (OR 0.43, p = 0.003) and CPR (OR 0.40, p = 0.0007) compared to those mild CE. Mild CE showed no influence on the IVF outcome as compared to women without CE (OPR/LBR, CPR and MR: p = ns). Based on this data analysis, CE significantly reduces OPR/LBR and CPR in women undergoing IVF. Importantly, CE resolution after antibiotic therapy may improves IVF outcome, leading to similar OPR/LBR and CPR as compared to unaffected patients. The negative effects of CE on IVF outcome may be restricted to severe disease, whereas mild CE may have no influence on IVF success.

MUM-1 immunohistochemistry has high accuracy and reliability in the diagnosis of chronic endometritis: a multi-centre comparative study with CD-138 immunostaining

PURPOSE

The current gold standard for chronic endometritis (CE) diagnosis is immunohistochemistry (IHC) for CD-138. However, IHC for CD-138 is not exempt from diagnostic limitations. The aim of our study was to evaluate the reliability and accuracy of MUM-1 IHC, as compared with CD-138.

METHODS

This is a multi-centre, retrospective, observational study, which included three tertiary hysteroscopic centres in university teaching hospitals. One hundred ninety-three consecutive women of reproductive age were referred to our hysteroscopy services due to infertility, recurrent miscarriage, abnormal uterine bleeding, endometrial polyps or myomas. All women underwent hysteroscopy plus endometrial biopsy. Endometrial samples were analysed through histology, CD138 and MUM-1 IHC. The primary outcome was to evaluate the diagnostic accuracy of MUM-1 IHC for CE, as compared with CD-138 IHC.

RESULTS

Sensitivity and specificity of CD-138 and MUM-1 IHC were respectively 89.13%, 79.59% versus 93.48% and 85.03%. The overall diagnostic accuracy of MUM-1 and CD-138 IHC were similar (AUC = 0.893 vs AUC = 0.844). The intercorrelation coefficient for single measurements was high between the two techniques (ICC = 0.831, 0.761-0.881 95%CI). However, among CE positive women, MUM-1 allowed the identification of higher number of plasma cells/hpf than CD-138 (6.50 [SD 4.80] vs 5.05 [SD 3.37]; p = 0.017). Additionally, MUM-1 showed a higher inter-observer agreement as compared to CD-138.

CONCLUSION

IHC for MUM-1 and CD-138 showed a similar accuracy for detecting endometrial stromal plasma cells. Notably, MUM-1 showed higher reliability in the paired comparison of the individual samples than CD-138. Thus, MUM-1 may represent a novel, promising add-on technique for the diagnosis of CE.

Association between Endometrial Polyps and Chronic Endometritis: Is It Time for a Paradigm Shift in the Pathophysiology of Endometrial Polyps in Pre-Menopausal Women? Results of a Systematic Review and Meta-Analysis

BACKGROUND

Chronic endometritis (CE) and endometrial polyps (EPs) are common conditions in reproductive age women. CE is an infectious disorder of the endometrium characterized by signs of chronic inflammation at hysteroscopic and histological analyses. EPs are abnormal endometrial growths containing glands, stroma and blood vessels projecting from the lining of the uterus. During the last years, different authors have investigated the correlation between CE and EPs, with controversial results. The aim of this study was to summarize available evidence on the potential correlation between CE and EPs.

DESIGN

Systematic literature review and meta-analysis.

METHODS

Observational-studies were identified by searching electronic databases from their inception to September 2021. Only studies on pre-menopausal women were included. Statistical analysis was performed using MedCalc 16.4.3 (Ostend, Belgium) and Review Manager version 5.3 (Nordic Cochrane Centre, Cochrane Collaboration). The summary measures were reported as pooled proportion or odds ratio (OR) with 95% confidence interval (CI). The primary outcome was to evaluate the prevalence of CE in women with EPs. The secondary outcome was to determine the prevalence of CD-138-positive EPs among EPs. Tertiary outcomes were to compare the prevalence of CE in women with EPs versus women with a non-polypoid endometrium and to compare the prevalence of CE in women with a single EP versus women with multiple EPs.

RESULTS

Eight observational studies (n = 3225 patients) were included in quantitative synthesis. Pooled prevalence of CE among women with EPs was 51.35% (95% CI, 27.24-75.13%). Pooled proportion of CD-138-positive EPs among EPs was 70.73% (95% CI, 55.73-83.68%). Women with EPs showed higher prevalence of CE compared to women without EPs (OR 3.07, 95% CI 1.59-5.95). Women with ≥3 EPs had higher prevalence of CE then women with a single EP (OR 3.43, 95% CI 1.83-6.46).

CONCLUSIONS

In pre-menopausal women, CE and EPs may have a dependent relationship and may represent two consequent steps of a common pathological process.