Incidence of Pelvic Inflammatory Disease Associated With Mycoplasma genitalium Infection: Evidence Synthesis of Cohort Study Data

Research progress on the interaction between intestinal flora and microRNA in pelvic inflammatory diseases

Pelvic inflammatory disease (PID) is a common infectious disease of the female upper reproductive tract, and its pathological basis is immune inflammatory response. The imbalance of gut microflora (GM) may lead to the development of inflammatory process. A large number of studies have shown that fecal microbiota transplantation, probiotics, bacteria, prebiotics, and dietary intervention may play a potential role in remodeling GM and treating diseases. MicroRNAs (miRNAs) are involved in cell development, proliferation, apoptosis and other physiological processes. In addition, they play an important role in the inflammatory process, participating in the regulation of proinflammatory and anti-inflammatory pathways. Differences in miRNA profiles may be PID diagnostic tools and serve as prognostic markers of the disease. The relationship between miRNA and GM has not been fully elucidated. Recent studies have shown the role of miRNA in the regulation and induction of GM dysbiosis. In turn, microbiota can regulate the expression of miRNA and improve the immune status of the body. Therefore, this review aims to describe the interaction between GM and miRNA in PID, and to find potential precise targeted therapy for PID.

Update in Epidemiology and Management of Mycoplasma genitalium Infections

Mycoplasma genitalium is a frequent cause of urogenital syndromes in men and women and is associated with adverse sequelae in women. M genitalium also infects the rectum, and may cause proctitis, but rarely infects the pharynx. Diagnosis requires nucleic acid amplification testing. Antibiotic resistance is widespread: more than half of infections are resistant to macrolides and fluoroquinolone resistance is increasing. Resistance-guided therapy is recommended for symptomatic patients, involving initial treatment with doxycycline to reduce organism load followed by azithromycin for macrolide-sensitive infections or moxifloxacin for macrolide-resistant infections. Neither screening nor tests of cure are recommended in asymptomatic persons.

Latest Advances in Laboratory Detection of Mycoplasma genitalium

Mycoplasma genitalium is an important sexually transmitted pathogen affecting both men and women. Its extremely slow growth in vitro and very demanding culture requirements necessitate the use of molecular-based diagnostic tests for its detection in clinical specimens. The recent availability of U.S. Food and Drug Administration (FDA)-cleared commercial molecular-based assays has enabled diagnostic testing to become more widely available in the United States and no longer limited to specialized reference laboratories. Advances in the knowledge of the epidemiology and clinical significance of M. genitalium as a human pathogen made possible by the availability of molecular-based testing have led to updated guidelines for diagnostic testing and treatment that have been published in various countries. This review summarizes the importance of M. genitalium as an agent of human disease, explains the necessity of obtaining a microbiological diagnosis, describes currently available diagnostic methods, and discusses how the emergence of antimicrobial resistance has complicated treatment alternatives and influenced the development of diagnostic tests for resistance detection, with an emphasis on developments over the past few years.

Potential therapeutic targets for combating Mycoplasma genitalium

Mycoplasma genitalium (M. genitalium) has emerged as a sexually transmitted infection (STI) all over the world in the last three decades. It has been identified as a cause of male urethritis, and there is now evidence that it also causes cervicitis and pelvic inflammatory disease in women. However, the precise role of M. genitalium in diseases such as pelvic inflammatory disease, and infertility is unknown, and more research is required. It is a slow-growing organism, and with the advent of the nucleic acid amplification test (NAAT), more studies are being conducted and knowledge about the pathogenicity of this organism is being elucidated. The accumulation of data has improved our understanding of the pathogen and its role in disease transmission. Despite the widespread use of single-dose azithromycin in the sexual health field, M. genitalium is known to rapidly develop antibiotic resistance. As a result, the media frequently refer to this pathogen as the "new STI superbug." Despite their rarity, antibiotics available today have serious side effects. As the cure rates for first-line antimicrobials have decreased, it is now a challenge to determine the effective antimicrobial therapy. In this review, we summarise recent M. genitalium research and investigate potential therapeutic targets for combating this pathogen.

The severity of depression is associated with pelvic inflammatory diseases: A cross-sectional study of the United States National Health and Nutrition Examinations from 2013 to 2018

Purpose

As depression in patients with pelvic inflammatory diseases (PID) has received increasing attention in recent years, this study aims to investigate the relationship between depression severity and risk factors for pelvic inflammatory disease, and to provide new perspectives in the treatment of PID.

Patients and methods

Multivariate regression was used to evaluate the association between pelvic inflammatory disease and the severity of depression. Females who participated in the United States National Health and Nutrition Examination Survey (NHANES) from 2013 to 2018 were included. In addition, risk factors for PID and depression were also included in the analysis as adjustment factors.

Results

The risk of developing PID was associated with depressive status (odds ratio, OR 1.10, 95% confidence interval, CI 1.08–1.12), especially in people with severe depression (odds ratio, OR 6.34, 95% confidence interval, CI 3.72–10.79). Subgroup analysis showed differences in the risk of PID among people with different characteristics.

Conclusion

This study showed that there may be a potential positive association between depressive status and the prevalence of PID in the United States adult female population. Depression should be actively looked for in all patients with PID and treated appropriately

Testing for Mycoplasma genitalium in pelvic inflammatory disease: A clinical audit

The records of women attending Gold Coast health hospital sites were retrospectively analysed to determine if women diagnosed with pelvic inflammatory disease (PID) were being tested for Mycoplasma genitalium (MG). Only 11.4% of 299 women were tested for MG despite 74.2% being tested for Chlamydia trichomonas (CT) and Neisseria gonorrhoeae (NG). Only 9% of the women were treated with antibiotics which would treat macrolide-sensitive MG infection. Increasing education and awareness of MG and utilising reflex macrolide testing for MG will help direct effective antibiotic therapy and prevent the long-term sequalae of PID.

Ascending Reproductive Tract Infection in Pig-Tailed Macaques Inoculated with Mycoplasma genitalium

Mycoplasma genitalium is a sexually transmitted bacterial pathogen that causes urogenital disease in men and women. M. genitalium infections can persist for months to years and can ascend to the upper reproductive tract in women where it is associated with serious sequelae including pelvic inflammatory disease, tubal factor infertility, and preterm birth. An animal model is needed to understand immune evasion strategies that allow persistence, mechanisms of ascending infection, and factors associated with clearance. In earlier studies, we determined that pig-tailed macaques are susceptible to cervical infection; however, not all primates were successfully infected, persistence varied between animals, and ascension to the upper reproductive tract was not observed after 4 or 8 weeks of follow-up. Building on our previous findings, we refined our inoculation methods to increase infection rates, extended observation to 18 weeks, and comprehensively sampled the upper reproductive tract to detect ascending infection. With these improvements, we established infection in all (3/3) primates inoculated with M. genitalium and demonstrated lower tract persistence for 16 to 18 weeks. Ascension to the upper reproductive tract at endpoint was observed in two out of three primates. All three primates developed serum and local antibodies reacting primarily to the MgpB and MgpC adherence proteins. Elevated genital polymorphonuclear leukocytes (PMNs) and inflammatory cytokines and chemokines, erythema of the ectocervix in one primate, and histologic evidence of vaginitis and endocervicitis in two primates suggest a mild to moderate inflammatory response to infection. This model will be valuable to understand the natural history of M. genitalium infection including mechanisms of persistence, immune evasion, and ascension to the upper reproductive tract.

High rates of asymptomatic Mycoplasma genitalium infections with high proportion of genotypic resistance to first-line macrolide treatment among men enrolled in the Zurich primary HIV infection study

Background

Mycoplasma genitalium (Mg) is an emerging sexually transmitted pathogen among men who have sex with men (MSM). Resistance to recommended antimicrobial agents are of public health concern. Few data exist on Mg infections in MSM diagnosed with human immunodeficiency virus (HIV) during primary HIV infection.

Methods

Participants of the Zurich Primary HIV Study (ClinicalTrials.gov Identifier NCT 00537966) were systematically offered screening for sexually transmitted infections (STIs) between April 2019 and September 2020. Screening was performed using an in-house polymerase chain reaction panel comprising Mg including genotypic resistance testing for macrolides and quinolones, Chlamydia trachomatis including serovars L1-L3, Neisseria gonorrhoeae, Treponema pallidum, and Hemophilus ducreyi.

Results

We screened 148 of 266 (55.6%) participants, with an overall total of 415 follow-up visits. Ninety-one percent were MSM. The incidence rate for all STIs was 47.0 (95% confidence interval [CI], 32.2–68.6) per 100 person-years. Mycoplasma genitalium was the most frequently detected pathogen: 30 participants (20%) presented with at least 1 Mg infection, corresponding to a period prevalence of 20.3% and incidence rate of 19.5 Mg infections (95% CI, 11.8–32.4). Most Mg infections (93%) were asymptomatic, and 9 (30%) participants showed spontaneous clearance. We detected high rates of antibiotic resistance: 73.3% to macrolides, 3.3% to quinolones, and 13.3% resistance to both antibiotics.

Conclusions

The high prevalence of mostly asymptomatic Mg infections and high rate of spontaneous clearance support cautious initiation for treatment. The high proportion of macrolide-resistant strains suggests that a genotypic determination of resistance should be standard of care. Moxifloxacin should be the preferred treatment option for symptomatic Mg infections among MSM if resistance testing is unavailable.

Evaluation of Clinical, Gram Stain, and Microbiological Cure Outcomes in Men Receiving Azithromycin for Acute Nongonococcal Urethritis: Discordant Cures Are Associated With Mycoplasma genitalium Infection

BACKGROUND

In men with nongonococcal urethritis (NGU), clinicians and patients rely on clinical cure to guide the need for additional testing/treatment and when to resume sex, respectively; however, discordant clinical and microbiological cure outcomes do occur. How accurately clinical cure reflects microbiological cure in specific sexually transmitted infections (STIs) is unclear.

METHODS

Men with NGU were tested for Neisseria gonorrhoeae, Chlamydia trachomatis (CT), Mycoplasma genitalium (MG), Trichomonas vaginalis, urethrotropic Neisseria meningitidis ST-11 clade strains, and Ureaplasma urealyticum (UU). Men received azithromycin 1 g and returned for a 1-month test-of-cure visit. In MG infections, we evaluated for the presence of macrolide resistance-mediating mutations (MRMs) and investigated alternate hypotheses for microbiological treatment failure using in situ shotgun metagenomic sequencing, phylogenetic analysis, multilocus sequence typing analyses, and quantitative PCR.

RESULTS

Of 280 men with NGU, 121 were included in this analysis. In the monoinfection group, 52 had CT, 16 had MG, 7 had UU, 10 had mixed infection, and 36 men had idiopathic NGU. Clinical cure rates were 85% for CT, 100% for UU, 50% for MG, and 67% for idiopathic NGU. Clinical cure accurately predicted microbiological cure for all STIs, except MG. Discordant results were significantly associated with MG-NGU and predominantly reflected microbiological failure in men with clinical cure. Mycoplasma genitalium MRMs, but not MG load or strain, were strongly associated with microbiological failure.

CONCLUSIONS

In azithromycin-treated NGU, clinical cure predicts microbiological cure for all STIs, except MG. Nongonococcal urethritis management should include MG testing and confirmation of microbiological cure in azithromycin-treated MG-NGU when MRM testing is unavailable.

Burden of Mycoplasma genitalium and Bacterial Coinfections in a Population-Based Sample in New Mexico

ABSTRACT

In this population-based US study, the overall prevalence of Mycoplasma genitalium was 1.95% (95% confidence interval [CI], 1.62%-2.34%), declining from 6.12% (95% CI, 4.72%-7.92%) in women aged 21 to 24 years to 0.48% (95% CI, 0.25%-0.94%) in women aged 40 to 64 years. The prevalence of coinfections with Chlamydia trachomatis and Trichomonas vaginalis was low.

What Do Diagnoses of Pelvic Inflammatory Disease in Specialist Sexual Health Services in England Tell Us About Chlamydia Control?

BACKGROUND

Pelvic inflammatory disease (PID) is an outcome measure for the evaluation of chlamydia screening programs. We explore PID diagnoses in specialist sexual health services (SSHSs) in England to inform the evaluation of the National Chlamydia Screening Programme, which was implemented nationally in 2008.

METHODS

We conducted descriptive analyses using data on diagnoses of PID-with and without Chlamydia trachomatis (CT) and/or Neisseria gonorrhoeae (GC)-by age and year of birth, in SSHSs between 2009 and 2019 from the GUMCAD STI Surveillance System database. Rates were calculated per 100 000 females residing in England.

RESULTS

CT screening activity peaked in 2010. The rates of all PID diagnoses decreased between 2009 and 2019 by 39%. CT-associated PID (CT-PID) declined by 58%, and nonspecific PID declined by 37%. GC-PID increased by 34%. CT-PID decreased across all age groups with the highest observed decline, 71%, in 15- to 19-year-olds. A dose-response relationship was observed between CT-PID rates and screening, with rates lowest in those with the greatest exposure to screening.

CONCLUSIONS

There was a marked decline in diagnoses of CT-PID, and nonspecific PID, at SSHSs after the introduction of widespread chlamydia screening, whereas GC-PID diagnoses increased. This ecological trend was broadly consistent with what we would have expected to see if widespread screening reduced the incidence of chlamydia-associated PID (and of nonspecific PID), as has been observed in randomized controlled trials of screening.

Subtractive Genomics Approach for Identification of Novel Therapeutic Drug Targets in Mycoplasma genitalium

Mycoplasma genitalium infection is a sexually transmitted infection that causes urethritis, cervicitis, and pelvic inflammatory disease (PID) in men and women. The global rise in antimicrobial resistance against recommended antibiotics for the treatment of M. genitalium infection has triggered the need to explore novel drug targets against this pathogen. The application of a bioinformatics approach through subtractive genomics has proven highly instrumental in predicting novel therapeutic targets against a pathogen. This study aimed to identify essential and non-homologous proteins with unique metabolic pathways in the pathogen that could serve as novel drug targets. Based on this, a manual comparison of the metabolic pathways of M. genitalium and the human host was done, generating nine pathogen-specific metabolic pathways. Additionally, the analysis of the whole proteome of M. genitalium using different bioinformatics databases generated 21 essential, non-homologous, and cytoplasmic proteins involved in nine pathogen-specific metabolic pathways. The further screening of these 21 cytoplasmic proteins in the DrugBank database generated 13 druggable proteins, which showed similarity with FDA-approved and experimental small-molecule drugs. A total of seven proteins that are involved in seven different pathogen-specific metabolic pathways were finally selected as novel putative drug targets after further analysis. Therefore, these proposed drug targets could aid in the design of potent drugs that may inhibit the functionality of these pathogen-specific metabolic pathways and, as such, lead to the eradication of this pathogen.

The clinical indications for testing women for Mycoplasma genitalium

BACKGROUND

While the contribution of Mycoplasma genitalium (MG) to symptoms in men is well described, less is known about its association with common genital symptoms in women. We aimed to determine the prevalence of MG and macrolide resistance, and its association with common genital symptoms in women attending a sexual health service, to inform indications for testing and clinical practice.

METHODS

We undertook a cross-sectional study of symptomatic and asymptomatic women attending Melbourne Sexual Health Centre (MSHC), between April 2017 and April 2019. Women were tested for MG and macrolide resistance, Chlamydia trachomatis (CT), Neisseria gonorrhoeae, Trichomonas vaginalis, bacterial vaginosis and vulvovaginal candidiasis. Women completed a questionnaire on symptoms, and symptomatic women underwent examination. The prevalence of MG (and macrolide resistance) and other genital infections was calculated with 95% CIs, and associations between these outcomes and specific genital symptoms were examined using logistic regression.

RESULTS

Of 1318 women, 83 (6%, 95% CI: 5% to 8%) had MG, of which 39 (48%, 95% CI: 36% to 59%) had macrolide-resistant MG; 103 (8%, 95% CI: 6% to 9%) women had CT. MG prevalence was similar in asymptomatic (10 of 195; 5%) and symptomatic (73 of 1108; 7%) women, p=0.506. MG was associated with mucopurulent cervicitis on examination (adjusted OR=4.38, 95% CI: 1.69 to 11.33, p=0.002), but was not associated with other specific genital symptoms or signs.

CONCLUSIONS

MG was as common as CT among women attending MSHC. MG was not associated with genital symptoms, but like CT, was significantly associated with cervicitis. These data provide evidence that routine testing for MG in women with common genital symptoms is not indicated. The presence of macrolide resistance in 48% of women supports use of resistance-guided therapy.

Chlamydia trachomatis and Mycoplasma genitalium prevalence and associated factors among women presenting to a pregnancy termination and contraception clinic, 2009-2019

BACKGROUND

Risk of pelvic inflammatory disease associated with Chlamydia trachomatis and Mycoplasma genitalium is increased after termination of pregnancy (TOP) and may be increased after insertion of intrauterine devices (IUDs). Screening prior to these procedures is recommended only for C. trachomatis. We examined C. trachomatis and M. genitalium prevalence and associated factors among women presenting to a pregnancy termination and contraception service over 10 years.

METHODS

Retrospective analysis of clinical data collected from 17 573 women aged 15-45 years in 2009-2019 and for 266 M. genitalium positive women tested for macrolide resistance-associated mutations in 2016-2019.

RESULTS

C. trachomatis and M. genitalium prevalence was 3.7% and 3.4%, respectively. In multivariable analyses, shared risk factors were younger age (p<0.001, for both C. trachomatis and M. genitalium), socioeconomic disadvantage (p=0.045 and p=0.008, respectively) and coinfection (p<0.001, for both sexually transmitted infections), with 10.1% of C. trachomatis positive women also positive for M. genitalium. Additional risk factors were earlier year of visit (p=0.001) for C. trachomatis and for M. genitalium residing outside a major city (p=0.013). The proportion of M. genitalium infections tested between 2016 and 2019 with macrolide resistance-associated mutations was 32.7%.

CONCLUSIONS

Given the high level of antimicrobial resistance and the prevalence of coinfection, testing C. trachomatis positive women for M. genitalium could be considered in this setting to prevent further spread of resistant infections. Further research is required into the causal link between M. genitalium and pelvic inflammatory disease in women undergoing TOP and IUD insertion.

Macrolide and fluoroquinolone associated mutations in Mycoplasma genitalium in a retrospective study of male and female patients seeking care at a STI Clinic in Guangzhou, China, 2016-2018

Background

Antimicrobial resistance in M. genitalium is a growing clinical problem. We investigated the mutations associated with macrolide and fluoroquinolone resistance, two commonly used medical regimens for treatment in China. Our aim is to analyze the prevalence and diversity of mutations among M. genitalium-positive clinical specimens in Guangzhou, south China.

Methods

A total of 154 stored M. genitalium positive specimens from men and women attending a STI clinic were tested for macrolide and fluoroquinolone mutations. M. genitalium was detected via TaqMan MGB real-time PCR. Mutations associated with macrolide resistance were detected using primers targeting region V of the 23S rRNA gene. Fluoroquinolone resistant mutations were screened via primers targeting topoisomerase IV (parC) and DNA gyrase (gyrA).

Results

98.7% (152/154), 95.5% (147/154) and 90.3% (139/154) of M. genitalium positive samples produced sufficient amplicon for detecting resistance mutations in 23S rRNA, gyrA and parC genes, respectively. 66.4% (101/152), 0.7% (1/147) and 77.7% (108/139) samples manifested mutations in 23S rRNA, gyrA and parC genes, respectively. A2072G (59/101, 58.4%) and S83I (79/108, 73.1%) were highly predominating in 23S rRNA and parC genes, respectively. Two samples had amino acid substitutions in gyrA (M95I and A96T, respectively). Two samples had two amino acid substitutions in parC (S83I + D87Y). 48.6% (67/138) of samples harbored both macrolide and fluoroquinolone resistance-associated mutations. The most common combination of mutations was A2072G (23S rRNA) and S83I (parC) (40/67, 59.7%). One sample had three amino acid changes in 23S rRNA, gyrA and parC genes (A2072G + A96T + S83I).

Conclusions

The high antimicrobial resistance rate of M. genitalium in Guangzhou is a very worrying problem and suggests that antimicrobial resistance testing and the development of new antibiotic regimens are crucially needed.