Plasma urocortin levels in the diagnosis of ovarian endometriosis

The causal relationship of depression, anxiety, and neuroticism with endometriosis: A bidirectional 2-sample Mendelian randomization study

Endometriosis, identified by the abnormal growth of endometrial cells beyond the inner lining of the uterus, often manifests through symptoms like painful menstruation and challenges in conceiving. Observational studies suggest that endometriosis is often comorbid with mental disorders, including anxiety and depression. The nature of these connections, whether they are causal, is still debated and calls for further empirical evidence. We utilized a bidirectional 2-sample Mendelian randomization (MR) approach, harnessing genome-wide association study data to explore the connections among depression, anxiety, neuroticism, and endometriosis. To scrutinize the causative connections between mental health issues and endometriosis, Inverse Variance Weighting (IVW) was employed as the primary analytical tool, complemented by Weighted Median Estimation, Simple mode, Weighted mode, and MR-Egger regression for additional analysis. To examine the potential for reverse causation, reverse MR was applied. To strengthen the reliability of our findings, we carried out sensitivity analyses that included heterogeneity tests, tests for pleiotropy, and leave-one-out analyses. The IVW analysis revealed a significant correlation between the genetic inclination towards depression and a heightened risk of developing endometriosis [Odds Ratio (OR) = 1.151, 95% Confidence Interval (CI) = 1.025-1.293, P = .017]. Similarly, a genetic predisposition to neuroticism was significantly associated with an increased risk of endometriosis (OR = 1.128, 95% CI = 1.038-1.226, P = .004). However, no causative link was found between genetic susceptibility to anxiety and the occurrence of endometriosis. Reverse MR analysis did not support a bidirectional genetic susceptibility between endometriosis and psychiatric disorders. The MR analysis presents genetic data supporting the notion that depression and neuroticism are risk factors for endometriosis. Conversely, it found no evidence of a causal connection between anxiety and the development of endometriosis. Enhancing mental health treatment should be considered a preventive measure against endometriosis.

Biomarkers of endometriosis

Endometriosis is one of the most severe female reproductive disorders, affecting 6-10% of women between 18 and 35. It is a gynaecological condition where endometrial tissue develops and settles outside the uterus. The aetiology of endometriosis is primarily influenced by genetic, epigenetic, and non-genetic variables, making it highly challenging to create a therapeutic therapy explicitly targeting the ectopic tissue. The delay in the treatment is due to the limitations in the diagnostic approaches, which are restricted to invasive techniques such as laparoscopy or laparotomy. This accords to 70% of the women being diagnosed at later stages. By understanding the subject, several treatment medications have been produced to lessen the disease's symptoms. Nevertheless, endometriosis cannot be permanently cured. A viable or persuasive standard screening test for endometriosis must be utilized in a clinical context. A helpful assessment method for the early identification of endometriosis could be biomarkers. A major research priority is the identification of a biomarker that is sensitive and specific enough for detecting endometriosis. The present article has reviewed studies published on the expression of biomarkers of endometriosis. It outlines various biomarkers from different sample types, such as serum/plasma and urine, in addition to tissue. This would provide a non-invasive approach to diagnosing the disease at the initial stages without any harmful repercussions. Future high-throughput advances in science and technology are anticipated to result in the creation of a potent remedy for endometriosis. To achieve successful outcomes, it is necessary to research the discussed biomarkers that demonstrate substantial results extensively.

Possible Correlation between Urocortin 1 (Ucn1) and Immune Parameters in Patients with Endometriosis

The etiology of endometriosis (EMS) has not been clearly elucidated yet, and that is probably the reason why its diagnostic process is frequently long-lasting and inefficient. Nowadays, the non-invasive diagnostic methods of EMS are still being sought. Our study aimed to assess the serum and peritoneal fluid levels of urocortin 1 (Ucn1) in patients with EMS and healthy women. Moreover, considering the immune background of the disease, the association between Ucn1 and several immune parameters was studied in both groups. We found that the serum Ucn1 level was significantly upregulated in women with EMS compared to healthy patients. Moreover, higher serum Ucn1 levels tended to correspond with more advanced stages of the disease (p = 0.031). Receiver operating characteristic (ROC) analysis revealed that based on serum Ucn1 levels, it is possible to distinguish deep infiltrating endometriosis (DIE) from among other EMS types. Together, these results indicate Ucn1 as a possible promising biomarker of EMS: however, not in isolation, but rather to enhance the effectiveness of other diagnostic methods.

Non-invasive diagnosis of endometriosis: Immunologic and genetic markers

Endometriosis, a benign gynecologic and chronic inflammatory disease, is defined by the presence of endometrial tissue outside the uterus characterized mainly by pelvic pain and infertility. Because endometriosis affects approximately 10% of females, it represents a significant socioeconomic burden worldwide having tremendous impact on daily quality of life. Accurate and prompt diagnosis is crucial for the management of this debilitating disorder. Unfortunately, diagnosis is typically delayed to lack of specific symptoms and readily accessible biomarkers. Although histopathologic examination remains the current gold standard, this approach is highly invasive and not applicable for early screening. Recent work has focused on the identification of reliable biomarkers including immunologic, ie, immune cells, antibodies and cytokines, as well as genetic and biochemical markers, ie, microRNAs, lncRNAs, circulating and mitochondrial nucleic acids, along with some hormones, glycoproteins and signaling molecules. Confirmatory research studies are, however, needed to more fully establish these markers in the diagnosis, progression and staging of these endometrial lesions.

Hormonal treatments for endometriosis: The endocrine background

Endometriosis is a benign uterine disorder characterized by menstrual pain and infertility, deeply affecting women's health. It is a chronic disease and requires a long term management. Hormonal drugs are currently the most used for the medical treatment and are based on the endocrine pathogenetic aspects. Estrogen-dependency and progesterone-resistance are the key events which cause the ectopic implantation of endometrial cells, decreasing apoptosis and increasing oxidative stress, inflammation and neuroangiogenesis. Endometriotic cells express AMH, TGF-related growth factors (inhibin, activin, follistatin) CRH and stress related peptides. Endocrine and inflammatory changes explain pain and infertility, and the systemic comorbidities described in these patients, such as autoimmune (thyroiditis, arthritis, allergies), inflammatory (gastrointestinal/urinary diseases) and mental health disorders.The hormonal treatment of endometriosis aims to block of menstruation through an inhibition of hypothalamus-pituitary-ovary axis or by causing a pseudodecidualization with consequent amenorrhea, impairing the progression of endometriotic implants. GnRH agonists and antagonists are effective on endometriosis by acting on pituitary-ovarian function. Progestins are mostly used for long term treatments (dienogest, NETA, MPA) and act on multiple sites of action. Combined oral contraceptives are also used for reducing endometriosis symptoms by inhibiting ovarian function. Clinical trials are currently going on selective progesterone receptor modulators, selective estrogen receptor modulators and aromatase inhibitors. Nowadays, all these hormonal drugs are considered the first-line treatment for women with endometriosis to improve their symptoms, to postpone surgery or to prevent post-surgical disease recurrence. This review aims to provide a comprehensive state-of-the-art on the current and future hormonal treatments for endometriosis, exploring the endocrine background of the disease.

Endometriosis and adverse pregnancy outcome

INTRODUCTION

Endometriosis is a gynecologic disease affecting approximately 10% of reproductive age women, around 21-47% of women presenting subfertility and 71-87% of women with chronic pelvic pain. Main symptoms are chronic pelvic pain, dysmenorrhea, dyspareunia and infertility that seem to be well controlled by oral contraceptive pill, progestogens, GnRh antagonists. The aim of this review was to illustrate the modern diagnosis of endometriosis during pregnancy, to evaluate the evolution of endometriotic lesions during pregnancy and the incidence of adverse outcomes.

EVIDENCE ACQUISITION

Published literature was retrieved through searches of the database PubMed (National Center for Biotechnology Information, US National Library of Medicine, Bethesda, MD, USA). We searched for all original articles published in English through April 2020 and decided to extract every notable information for potential inclusion in this review. The search included the following MeSH search terms, alone or in combination: "endometriosis" combined with "endometrioma," "biomarkers," "complications," "bowel," "urinary tract," "uterine rupture," "spontaneous hemoperitoneum in pregnancy" and more "adverse pregnancy outcome," "preterm birth," "miscarriage," "abruption placentae," "placenta previa," "hypertensive disorder," "preeclampsia," "fetal grow restriction," "small for gestation age," "cesarean delivery."

EVIDENCE SYNTHESIS

Pregnancy in women with endometriosis does not always lead to disappearance of symptoms and decrease in the size of endometriotic lesions, but it may be possible to observe a malignant transformation of ovarian endometriotic lesions. Onset of complications may be caused by many factors: chronic inflammation, adhesions, progesterone resistance and a dysregulation of genes involved in the embryo implantation. As results, the pregnancy can be more difficult because of endometriosis related complications (spontaneous hemoperitoneum [SH], bowel complications, etc.) or adverse outcomes like preterm birth, FGR, hypertensive disorders, obstetrics hemorrhages (placenta previa, abruptio placenta), miscarriage or cesarean section. Due to insufficient knowledge about its pathogenesis, currently literature data are contradictory and do not show a strong correlation between endometriosis and these complications except for miscarriage and cesarean delivery.

CONCLUSIONS

Future research should focus on the potential biological pathways underlying these relationships in order to inform patients planning a birth about possible complications during pregnancy.

The Potential of Non-Invasive Biomarkers for Early Diagnosis of Asymptomatic Patients with Endometriosis

Endometriosis is a disease that affects women of reproductive age and has a significantly negative impact on their well-being. The main symptoms are dysmenorrhoea, chronic pelvic pain and infertility. In many patients the diagnostic process is very long and can take up to 8-12 years. Laparoscopy, an invasive method, is still necessary to confirm the diagnosis. Therefore, development of more effective diagnostic markers appears to be of the utmost importance for early diagnosis of endometriosis and provision of appropriate treatment. From a clinical point of view, detection of early-stage endometriosis in asymptomatic patients is an ideal situation since early diagnosis of endometriosis may delay the onset of symptoms as well as prevent progression and complications. In the meantime, Cancer Antigen 125 (CA-125) is still the most frequently studied and used marker. Other glycoproteins, growth factors and immune markers seem to play an important role. However, the search for an ideal endometriosis marker is still underway. Further studies into the pathogenesis of endometriosis will help to identify biomarkers or sets of biomarkers with the potential to improve and speed up the diagnostic process in a non-invasive way.

Corticotropin-Releasing Factor Family: A Stress Hormone-Receptor System's Emerging Role in Mediating Sex-Specific Signaling

No organ in the body is impervious to the effects of stress, and a coordinated response from all organs is essential to deal with stressors. A dysregulated stress response that fails to bring systems back to homeostasis leads to compromised function and ultimately a diseased state. The components of the corticotropin-releasing factor (CRF) family, an ancient and evolutionarily conserved stress hormone-receptor system, helps both initiate stress responses and bring systems back to homeostasis once the stressors are removed. The mammalian CRF family comprises of four known agonists, CRF and urocortins (UCN1–3), and two known G protein-coupled receptors (GPCRs), CRF₁ and CRF₂. Evolutionarily, precursors of CRF- and urocortin-like peptides and their receptors were involved in osmoregulation/diuretic functions, in addition to nutrient sensing. Both CRF and UCN1 peptide hormones as well as their receptors appeared after a duplication event nearly 400 million years ago. All four agonists and both CRF receptors show sex-specific changes in expression and/or function, and single nucleotide polymorphisms are associated with a plethora of human diseases. CRF receptors harbor N-terminal cleavable peptide sequences, conferring biased ligand properties. CRF receptors have the ability to heteromerize with each other as well as with other GPCRs. Taken together, CRF receptors and their agonists due to their versatile functional adaptability mediate nuanced responses and are uniquely positioned to orchestrate sex-specific signaling and function in several tissues.

Biomarkers for the Noninvasive Diagnosis of Endometriosis: State of the Art and Future Perspectives

BACKGROUND

Early and accurate diagnosis of endometriosis is crucial for the management of this benign, yet debilitating pathology. Despite the advances of modern medicine, there is no common ground regarding the pathophysiology of this disease as it continues to affect the quality of life of millions of women of reproductive age. The lack of specific symptoms often determines a belated diagnosis. The gold standard remains invasive, surgery followed by a histopathological exam. A biomarker or a panel of biomarkers is easy to measure, usually noninvasive, and could benefit the clinician in both diagnosing and monitoring the treatment response. Several studies have advanced the idea of biomarkers for endometriosis, thereby circumventing unnecessary invasive techniques. Our paper aims at harmonizing the results of these studies in the search of promising perspectives on early diagnosis.

METHODS

We selected the papers from Google Academic, PubMed, and CrossRef and reviewed recent articles from the literature, aiming to evaluate the effectiveness of various putative serum and urinary biomarkers for endometriosis.

RESULTS

The majority of studies focused on a panel of biomarkers, rather than a single biomarker and were unable to identify a single biomolecule or a panel of biomarkers with sufficient specificity and sensitivity in endometriosis.

CONCLUSION

Noninvasive biomarkers, proteomics, genomics, and miRNA microarray may aid the diagnosis, but further research on larger datasets along with a better understanding of the pathophysiologic mechanisms are needed.

Anti-inflammatory cytokines in endometriosis

Although the pathogenesis of endometriosis is not fully understood, it is often considered to be an inflammatory disease. An increasing number of studies suggest that differential expression of anti-inflammatory cytokines (e.g., interleukin-4 and -10, and transforming growth factor-β1) occurs in women with endometriosis, including in serum, peritoneal fluid and ectopic lesions. These anti-inflammatory cytokines also have indispensable roles in the progression of endometriosis, including by promoting survival, growth, invasion, differentiation, angiogenesis, and immune escape of the endometriotic lesions. In this review, we provide an overview of the expression, origin, function and regulation of anti-inflammatory cytokines in endometriosis, with brief discussion and perspectives on their future clinical implications in the diagnosis and therapy of the disease.

Urocortin Expression in Endometriosis: A Systematic Review

Urocortin (UCN) is a neuropeptide that belongs to the corticotrophin-releasing hormone family and is expressed by eutopic and ectopic human endometria. The past years, this expression has been thoroughly investigated in the field of endometriosis. The objective of this systematic review is to accumulate current evidence related to the expression of UCN in tissue and blood samples of patients suffering from endometriosis. Literature search was designed accord- ing to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and primarily conducted using the Medline (1966-2018), Scopus (2004-2018), EMBASE (1947-2018) and Clinicaltrials.gov (2008- 2018) databases, along with the reference lists of electronically retrieved full-text papers. Overall, eight studies were retrieved. Current evidence suggests that the expression of UCN is increased in patients with ovarian endometriomas and that its levels may correlate with the severity of the disease. The diagnostic efficacy of UCN1 plasma levels was evaluated in three studies. Two of them suggested that the sensitivity and specificity of the method may reach, and even exceed, 80%. However, the wide variation in outcome reporting and outcome reporting measures in endome- triosis among the included studies precludes meta-analysis of available data. Therefore, although UCN seems to be a promising biomarker for the identification and follow-up of patients that suffer from endometriosis, more studies are needed to reach firm conclusions with respect to its predictive accuracy.

Noninvasive diagnosis of endometriosis: Review of current peripheral blood and endometrial biomarkers

A noninvasive biomarker-based test could help shorten the diagnostic delay for endometriosis. The most investigated biomarker sources are peripheral blood and endometrium. Discovery of endometriosis biomarkers is often hypothesis-driven, i.e. when one or a few biomarkers are investigated based on their role in the disease pathogenesis. Alternatively, a hypothesis-generating approach has been followed using the "omics" technologies. A variety of biomarkers for endometriosis have been investigated, but no biomarker has been validated for clinical use. Many challenges lie ahead in the endometriosis biomarker field. In the future, harmonized collection and reporting methods should allow large-scale international collaboration for highly powered studies.

Plasma urocortin-1 as a preoperative marker of endometriosis in symptomatic women

Accurate noninvasive diagnostic tests for endometriosis are still missing. This study evaluated the predictive value of the neuropeptide urocortin 1 (Ucn1) to detect pelvic endometriosis in symptomatic women. We enrolled prospectively 97 consecutive women submitted to gynecologic laparoscopy for chronic or acute pelvic pain, infertility or adnexal mass. Preoperative blood samples were assayed for Ucn1 using enzyme immunoassay. Patients with endometriosis had higher plasma Ucn1 levels compared to patients with no lesions (median 59 vs. 34 pg/ml, p < .01, Dunn's test). Elevated plasma Ucn1 levels were found among all endometriosis phenotypes (superficial peritoneal lesions, ovarian endometrioma, and deep infiltrating endometriosis, p < .05 vs. no lesions). Receiver operating characteristics curve analysis identified plasma Ucn1 > 46 pg/mL as the best cutoff point to detect endometriosis vs. no lesions, with 76% sensitivity and 88% specificity (area under the curve [AUC] 0.827, 95% confidence interval [CI] 0.695 - 0.959), but no cutoff could accurately distinguish endometriosis from other pathological conditions (AUC 0.593 [95% CI 0.474 - 0.711]). In women with chronic pelvic pain, infertility, or both symptoms, the probability of endometriosis (positive predictive value) increased consistently with the increase of plasma Ucn1 levels. The present findings suggest that high plasma Ucn1 levels increase the likelihood of endometriosis in symptomatic women.

Expression and Role of Peptides, Proteins and Growth Factors in the Pathogenesis of Endometriosis

Growing evidence is demonstrating that several peptides (corticotrophin-releasing factor, urocortins, ghrelin), proteins (leptin, adiponectin) and growth factors (vascular endothelial growth factor; epidermal growth factor family of growth factors and receptors, fibroblast growth factor, insulin like growth factor and insulin like growth factor-binding proteins, transforming growth factor-β and, activin A and related proteins) are expressed in endometriotic implants, and locally play a relevant role in affecting the biological mechanisms leading to endometriosis. They establish a complex network of interactions by which they are therefore able to stimulate angiogenesis, inflammatory cell recruitment and reaction, the growth of endometriotic tissue and its survival through the modulation of the narrow immune system. This review will evaluate the role played by several regulatory peptides, proteins and growth factors in affecting endometrial physiology and the putative mechanisms advocated to explain endometriosis (angiogenesis, cellular and humoral immunity, inflammatory response, endometrial cell proliferation, activation, motility, adhesion and invasion).

Evaluation of the Ki-67 Proliferation Index and Urocortin Expression in Women with Ovarian Endometriomas

OBJECTIVE

The reasons why endometriosis is more aggressive and invasive in some patients are unknown. Despite the importance of population-based clinically defined risk factors in the prediction of recurrence, biochemical markers obtained from the patient are more valuable for prediction on an individual basis. Therefore, the discovery of significant potential biomarkers could be useful to clinicians for shedding light on the pathogenesis of endometriosis and in the monitoring recurrence.

MATERIALS AND METHODS

This study included 50 patients who underwent surgery for ovarian cysts that were diagnosed as endometrioma. The age of the patients, stage of the endometriosis, diameter and localization of endometriomas, type of surgery, and pre- and postoperative cancer antigen 125 (CA125) levels were compared between patients with and without recurrence. The archived pathology slides were stained with Ki-67 and anti-urocortin antibodies for reevaluation. By comparing the pathology parameters of the patients with and without recurrence, the association between these parameters and recurrence was investigated.

RESULTS

The median Ki-67 proliferation index of the patients with recurrence (7.5±6.5) was statistically significant compared with that of the patients without recurrence (1±4) (p=0.003). The urocortin epithelial staining intensity and percentage were not found to be statistically significant in comparison. A statistically significant difference was determined between postoperative CA125 median levels of patients without recurrence (10±17.6) and those of patients with recurrence (29.9±18.1) (p=0.003).

CONCLUSION

The Ki-67 proliferation index may be useful for predicting prognosis and recurrence risk.

[Conservative management of endometrioma in women undergoing in vitro fertilization]

Endometriosis is a chronic disease. The pathogenesis is actually still unclear. Endometriosis is responsible for infertility and/or pelvic pain. One of the most important features of the disease is the heterogeneity (clinical and anatomical). Among the different phenotypes of endometriosis, the ovarian endometrioma seems to most important lesion in the management of endometriosis-related infertility. Surgical treatment is associated to a decrease of the ovarian reserve and a potential detrimental effect on in vitro fecondation (IVF) outcomes. Thus, the choice between conservative or surgical management of endometrioma before IVF is actually debated. The advantages and drawback of surgical and conservative management should be discussed before to plan the treatment. In the present review, we aimed at assessing the risks of a conservative management of endometrioma as compared to surgery before IVF.

Urocortin and corticotrophin-releasing hormone receptor type 2 mRNA are highly expressed in deep infiltrating endometriotic lesions

Ovarian endometrioma (OMA) and deep infiltrating endometriosis (DIE) are the most severe forms of endometriosis, but different pathogenetic mechanisms and clinical symptoms distinguish these two forms. Corticotrophin-releasing hormone (CRH) and urocortin (Ucn) are endometrial neuropeptides involved in tissue differentiation and inflammation. The expression of CRH, Ucn, Ucn2, CRH-receptors (type-1 and type-2) and inflammatory enzymes phospholipase-A2 group IIA (PLA2G2A) and cycloxygenase-2 (COX2) were evaluated in OMA (n = 22) and DIE (n = 26). The effect of CRH or Ucn on COX2 mRNA expression was evaluated in cultured human endometrial stromal cells. In DIE lesions, CRH, Ucn and CRH-R2 mRNA levels were significantly higher than in OMA (P < 0.01, P < 0.001 and P < 0.05, respectively); DIE lesions showed a higher expression of COX2 (P < 0.01) and PLA2G2A (P < 0.05) mRNA than OMA, which was positively correlated with CRH-R2 mRNA expression (P < 0.05). Intense immunostaining for CRH and Ucn was shown in DIE. Treatment of cultured endometrial stromal cells with Ucn significantly increased COX2 mRNA expression (P < 0.01); this effect was reversed by the CRH-R2 antagonist astressin-2B. In DIE, DIE lesions highly express neuropeptide and enzyme mRNAs, supporting a strong activation of inflammatory pathways.

Role of urocortin in pregnancy: An update and future perspectives

The activities of corticotropin-releasing factor (CRF) and related peptides are mediated a number of receptors with seven transmembrane domains that are coupled to the Gs and Gq proteins. These receptors are known as CRF-Rs. In vitro studies have evidenced that urocortin (UCN) and CRF provoke an increase in the contractility of the uterus which is induced by endometrial prostaglandin F2a. Furthermore, through trophoblasts, it stimulates the secretion of adrenocorticotropic hormone (ACTH) and prostaglandin PGE2 and has a vasodilatory effect on the placenta. While it is well known that the placenta produces considerable quantities of CRF, several studies have, however, excluded that the placenta can generate significant quantities of UCN. In the short term, the human fetal adrenal gland produces more cortisol and dehydroepiandrosterone sulfate. The gestational tissues express UCN3 and UCN2 mRNA in cytotrophoblast and syncytiotrophoblast cells, while UCN2 is only to be found in the maternal and fetal vessels and amniotic cells. Nevertheless, gestational tissues express UCN2 and UCN3 differentially and do not stimulate placental ACTH secretion. In term pregnancies, maternal plasma levels of CRF and UCN are lower than at the beginning of pregnancy and are correlated to labor onset. Conversely, they do not decrease in post-term pregnancies. This evidence would seem to indicate that the fine-regulated expression of these neuropeptides is important in determining the duration of human gestation. In this scenario, low concentrations of UCN in the amniotic fluid at mid-term may be considered a sign of predisposition to preterm birth.

Blood biomarkers for the non-invasive diagnosis of endometriosis

BACKGROUND

About 10% of reproductive-aged women suffer from endometriosis, a costly chronic disease causing pelvic pain and subfertility. Laparoscopy is the gold standard diagnostic test for endometriosis, but is expensive and carries surgical risks. Currently, there are no non-invasive or minimally invasive tests available in clinical practice to accurately diagnose endometriosis. Although other reviews have assessed the ability of blood tests to diagnose endometriosis, this is the first review to use Cochrane methods, providing an update on the rapidly expanding literature in this field.

OBJECTIVES

To evaluate blood biomarkers as replacement tests for diagnostic surgery and as triage tests to inform decisions on surgery for endometriosis. Specific objectives include:1. To provide summary estimates of the diagnostic accuracy of blood biomarkers for the diagnosis of peritoneal, ovarian and deep infiltrating pelvic endometriosis, compared to surgical diagnosis as a reference standard.2. To assess the diagnostic utility of biomarkers that could differentiate ovarian endometrioma from other ovarian masses.

SEARCH METHODS

We did not restrict the searches to particular study designs, language or publication dates. We searched CENTRAL to July 2015, MEDLINE and EMBASE to May 2015, as well as these databases to 20 April 2015: CINAHL, PsycINFO, Web of Science, LILACS, OAIster, TRIP, ClinicalTrials.gov, DARE and PubMed.

SELECTION CRITERIA

We considered published, peer-reviewed, randomised controlled or cross-sectional studies of any size, including prospectively collected samples from any population of reproductive-aged women suspected of having one or more of the following target conditions: ovarian, peritoneal or deep infiltrating endometriosis (DIE). We included studies comparing the diagnostic test accuracy of one or more blood biomarkers with the findings of surgical visualisation of endometriotic lesions.

DATA COLLECTION AND ANALYSIS

Two authors independently collected and performed a quality assessment of data from each study. For each diagnostic test, we classified the data as positive or negative for the surgical detection of endometriosis, and we calculated sensitivity and specificity estimates. We used the bivariate model to obtain pooled estimates of sensitivity and specificity whenever sufficient datasets were available. The predetermined criteria for a clinically useful blood test to replace diagnostic surgery were a sensitivity of 0.94 and a specificity of 0.79 to detect endometriosis. We set the criteria for triage tests at a sensitivity of ≥ 0.95 and a specificity of ≥ 0.50, which 'rules out' the diagnosis with high accuracy if there is a negative test result (SnOUT test), or a sensitivity of ≥ 0.50 and a specificity of ≥ 0.95, which 'rules in' the diagnosis with high accuracy if there is a positive result (SpIN test).

MAIN RESULTS

We included 141 studies that involved 15,141 participants and evaluated 122 blood biomarkers. All the studies were of poor methodological quality. Studies evaluated the blood biomarkers either in a specific phase of the menstrual cycle or irrespective of the cycle phase, and they tested for them in serum, plasma or whole blood. Included women were a selected population with a high frequency of endometriosis (10% to 85%), in which surgery was indicated for endometriosis, infertility work-up or ovarian mass. Seventy studies evaluated the diagnostic performance of 47 blood biomarkers for endometriosis (44 single-marker tests and 30 combined tests of two to six blood biomarkers). These were angiogenesis/growth factors, apoptosis markers, cell adhesion molecules, high-throughput markers, hormonal markers, immune system/inflammatory markers, oxidative stress markers, microRNAs, tumour markers and other proteins. Most of these biomarkers were assessed in small individual studies, often using different cut-off thresholds, and we could only perform meta-analyses on the data sets for anti-endometrial antibodies, interleukin-6 (IL-6), cancer antigen-19.9 (CA-19.9) and CA-125. Diagnostic estimates varied significantly between studies for each of these biomarkers, and CA-125 was the only marker with sufficient data to reliably assess sources of heterogeneity.The mean sensitivities and specificities of anti-endometrial antibodies (4 studies, 759 women) were 0.81 (95% confidence interval (CI) 0.76 to 0.87) and 0.75 (95% CI 0.46 to 1.00). For IL-6, with a cut-off value of > 1.90 to 2.00 pg/ml (3 studies, 309 women), sensitivity was 0.63 (95% CI 0.52 to 0.75) and specificity was 0.69 (95% CI 0.57 to 0.82). For CA-19.9, with a cut-off value of > 37.0 IU/ml (3 studies, 330 women), sensitivity was 0.36 (95% CI 0.26 to 0.45) and specificity was 0.87 (95% CI 0.75 to 0.99).Studies assessed CA-125 at different thresholds, demonstrating the following mean sensitivities and specificities: for cut-off > 10.0 to 14.7 U/ml: 0.70 (95% CI 0.63 to 0.77) and 0.64 (95% CI 0.47 to 0.82); for cut-off > 16.0 to 17.6 U/ml: 0.56 (95% CI 0.24, 0.88) and 0.91 (95% CI 0.75, 1.00); for cut-off > 20.0 U/ml: 0.67 (95% CI 0.50 to 0.85) and 0.69 (95% CI 0.58 to 0.80); for cut-off > 25.0 to 26.0 U/ml: 0.73 (95% CI 0.67 to 0.79) and 0.70 (95% CI 0.63 to 0.77); for cut-off > 30.0 to 33.0 U/ml: 0.62 (95% CI 0.45 to 0.79) and 0.76 (95% CI 0.53 to 1.00); and for cut-off > 35.0 to 36.0 U/ml: 0.40 (95% CI 0.32 to 0.49) and 0.91 (95% CI 0.88 to 0.94).We could not statistically evaluate other biomarkers meaningfully, including biomarkers that were assessed for their ability to differentiate endometrioma from other benign ovarian cysts.Eighty-two studies evaluated 97 biomarkers that did not differentiate women with endometriosis from disease-free controls. Of these, 22 biomarkers demonstrated conflicting results, with some studies showing differential expression and others no evidence of a difference between the endometriosis and control groups.

AUTHORS' CONCLUSIONS

Of the biomarkers that were subjected to meta-analysis, none consistently met the criteria for a replacement or triage diagnostic test. A subset of blood biomarkers could prove useful either for detecting pelvic endometriosis or for differentiating ovarian endometrioma from other benign ovarian masses, but there was insufficient evidence to draw meaningful conclusions. Overall, none of the biomarkers displayed enough accuracy to be used clinically outside a research setting. We also identified blood biomarkers that demonstrated no diagnostic value in endometriosis and recommend focusing research resources on evaluating other more clinically useful biomarkers.

Serum markers for the noninvasive diagnosis of endometriosis

Endometriosis is a disease that affects millions of women worldwide and its diagnosis is still challenging. Medical history, symptoms together with imaging data may address the correct diagnosis, but the gold standard remains laparoscopic assessment with histological confirmation. The development of serum markers as diagnostic tools for endometriosis may allow a prompt and noninvasive diagnosis. Several serum biomarkers have been investigated over the years, but none of these have shown a clinical utility and nowadays the more realistic diagnostic biomarker consists in a panel of biomarkers. The recent introduction of new technologies such as genomics and proteomics may represent the future perspective of endometriosis diagnosis.

Physical therapy and psychological intervention normalize cortisol levels and improve vitality in women with endometriosis

There is as yet no effective treatment for endometriosis. The objective of this study was to evaluate the effectiveness of submitting women with endometriosis and chronic pelvic pain to a therapeutic protocol involving physical and psychological therapy. Twenty-six female volunteers were submitted to a treatment protocol consisting of 2.5-h sessions, once a week for 10 weeks. We applied a Visual Analogue Scale, the Perceived Stress Questionnaire (PSQ), and the Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36). Morning, afternoon, and evening levels of cortisol were determined in saliva samples. The PSQ scores were significantly lower after treatment, whereas the scores for the SF-36 vitality and physical functioning domains were significantly higher. Salivary cortisol levels were higher after treatment in the samples collected in the morning, but not in those collected in the afternoon or evening. The post-treatment cortisol levels were similar to those reported for healthy women. There were positive correlations between vitality, role emotional, social functioning, and mental health, and negative correlations to perceived stress. In conclusion, the physical and psychological intervention protocol applied in this study to women suffering of endometriosis was effective in reducing perceived stress, normalizing cortisol levels, increasing vitality and improving physical functioning.

Endometriosis in adolescence

Endometriosis is a common cause of pelvic pain and infertility. The majority of women report symptoms since adolescence, and there are rare cases of endometriosis in premenarchal age patients. Symptoms in adolescence are similar to those in adulthood. Treatment usually consists of oral contraceptives and nonsteroidal anti-inflammatory drugs. In cases where this treatment is not successful, laparoscopy and biopsy of the lesions are necessary for diagnosis. However, emerging new technologies provide new options, in particular the use of serological markers.

Urocortin 2 and urocortin 3 in endometriosis: evidence for a possible role in inflammatory response

Urocortin 2 (Ucn 2) and urocortin 3 (Ucn 3) are neuropeptides expressed by human endometrium. This study evaluated (i) the expression of Ucn 2 and Ucn 3 mRNA in endometriotic lesions and in endometrium of women with endometriosis; (ii) the effect of Ucn 2 and Ucn 3 on cytokines secretion from cultured endometrial stromal cells. Endometriotic tissue was collected from endometrioma (n=39); endometrial specimens were obtained from women with (n=39) and without (n=41) endometriosis throughout menstrual cycle. Tissue specimens were analysed for Ucn 2 and Ucn 3 mRNA expression and peptide localization; the effects of Ucn 2 or Ucn 3 on tumour necrosis factor (TNF-α) and interleukin (IL-4) secretion from cultured endometrial stromal cells was studied. Ucn 2 and Ucn 3 mRNA expression and localization were assessed by RT-PCR and by immuohistochemistry, respectively; cytokines secretion were measured by ELISA. Results showed that endometriotic tissue expressed both Ucn 2 and Ucn 3, with Ucn 3 expression higher in ectopic than in eutopic endometrium. Endometrial Ucn 2 mRNA expression in controls showed peak values at early proliferative phase, while in endometriotic patients low expression and no significant changes throughout menstrual cycle were observed. Endometrial Ucn 3 mRNA expression was highest in late secretory phase in controls, while in endometriotic patients low levels and no menstrual-cycle-related changes were found. When added to cultured endometrial cell cultures, Ucn 2 significantly increased TNF-α (P<0.01) and IL-4 (P<0.001), while Ucn 3 induced an increase of IL-4 secretion (P<0.01). In conclusion, endometriotic tissue expressed and localized Ucn 2 and Ucn 3; patients with endometriosis showed Ucn 2 and Ucn 3 mRNA expression in eutopic endometrium lower than in control group, with no endometrial cycle-related changes. Ucn 2 and Ucn 3-modulated TNF-α and IL-4 secretion from culture endometrial cells. These data suggest a possible involvement of Ucn 2 and Ucn 3 in the mechanisms of endometriosis.

Peripheral biomarkers of endometriosis: a systematic review

BACKGROUND

Endometriosis is estimated to affect 1 in 10 women during the reproductive years. There is often delay in making the diagnosis, mainly due to the non-specific nature of the associated symptoms and the need to verify the disease surgically. A biomarker that is simple to measure could help clinicians to diagnose (or at least exclude) endometriosis; it might also allow the effects of treatment to be monitored. If effective, such a marker or panel of markers could prevent unnecessary diagnostic procedures and/or recognize treatment failure at an early stage.

METHODS

We used QUADAS (Quality Assessment of Diagnostic Accuracy Studies) criteria to perform a systematic review of the literature over the last 25 years to assess critically the clinical value of all proposed biomarkers for endometriosis in serum, plasma and urine.

RESULTS

We identified over 100 putative biomarkers in publications that met the selection criteria. We were unable to identify a single biomarker or panel of biomarkers that have unequivocally been shown to be clinically useful.

CONCLUSIONS

Peripheral biomarkers show promise as diagnostic aids, but further research is necessary before they can be recommended in routine clinical care. Panels of markers may allow increased sensitivity and specificity of any diagnostic test.

Circulating levels of stress associated peptide Urocortin in heart failure patients

The available data suggest that Urocortin (UCN), a cardioprotective and vasoactive peptide known from fish neuroendocrinology, is involved in cardiac regulation. The aim of this study was to determine UCN plasma concentrations in patients with heart failure (HF). Plasma concentrations of UCN, measured in 42 fully treated HF patients. UCN, were determined using a specific ELISA assay after acidic extraction with Sep-Pak C18 columns. Circulating levels of other neurohormones Nt-proBNP, Nt-proANP and Big ET-1 were also determined. Reference values were obtained from 20 healthy age- and sex-matched subjects. In comparison with controls, UCN plasma concentrations (geometric mean [95% CI]) were significantly increased in HF patients (88 pmol/L [75-105] vs 46 [39-54], p<0.001). As expected, the other neurohormones were also significantly increased in HF patients (Nt-proBNP: 3501 pg/ml [2356-5202] vs 35 [24-51], Nt-proANP: 5498 pg/ml [4336-6971] vs 324 [255-411] and Big ET-1: 15.8 pg/ml [13.6-18.4] vs 5.9 [5.2-6.8]; p<0.01 for all vs controls). No significant correlation was observed between UCN and the other HF biomarkers. Our results demonstrate that plasma concentrations of UCN are significantly increased in patients with HF and that UCN may participate in the neurohumoral response of HF.

Neuroendocrine circuitry and endometriosis: progesterone derivative dampens corticotropin-releasing hormone-induced inflammation by peritoneal cells in vitro

Clinical symptoms of endometriosis, such as pain and infertility, can be described as persistent stressors. Such continuous exposure to stress may severely affect the equilibrium and bidirectional communication of the endocrine and immune system, hereby further aggravating the progression of endometriosis. In the present study, we aimed to tease apart mediators that are involved in the stress response as well as in the progression of endometriosis. Women undergoing diagnostic laparoscopy due to infertility were recruited (n = 69). Within this cohort, early stage of endometriosis were diagnosed in n = 30 and advanced stage of endometriosis in n = 8. Levels of progesterone in serum were determined. Frequency of progesterone receptor (PR) expression on CD56(+) and CD8(+) peritoneal lymphocytes was analysed by flow cytometry. The production of tumour necrosis factor (TNF) and interleukin (IL)-10 by peritoneal leukocytes upon stimulation with the potent stress mediator corticotropin-releasing hormone (CRH) and the progesterone derivative dydrogesterone, or both, were evaluated. Furthermore, the production of progesterone-induced blocking factor (PIBF) by peritoneal leukocytes and the expression of PR in endometriotic tissue were investigated. Levels of progesterone in serum were decreased in women with endometriosis and inversely correlated to pain scores. Furthermore, an increased frequency of CD56(+)PR(+) and CD8(+)PR(+) peritoneal lymphocytes was present in advanced endometriosis. The TNF/IL-10 ratio, reflecting cytokine secretion by peritoneal cells, was higher in cells derived from endometriosis patients and could be further heightened by CRH stimulation, whereas stimulation with dydrogesterone abrogated the CRH-mediated inflammation. Finally, the expression of PIBF by peritoneal leukocytes was increased in endometriosis. Low levels of progesterone in the follicular phase could be responsible for the progression of endometriosis and related pain. Peripheral CRH, increasing upon high psychological stress, might contribute to the peritoneal inflammation present in endometriosis. The therapeutic application of progesterone derivatives, CRH blocking agents as well as improvement of stress coping may disrupt the vicious circle between the chronic peritoneal inflammation and high perception of psychological stress in endometriosis.