A profile of the FDA-approved and CE/IVD-marked Aptima Mycoplasma genitalium assay (Hologic) and key priorities in the management of M. genitalium infections

Advantages of Syndromic Diagnostics: Detection of the Pathogens Causing Urethritis/Cervicitis with the STI CNM Real-Time PCR Kit from Vitro S.A

The STI CNM Real-Time PCR Kit from Vitro S.A. (Spain) demonstrates high sensitivity and specificity, is cost-effective, and can detect the three main etiological agents of urethritis/cervicitis in a single multiplex PCR. Sexually transmitted infections (STIs) are a significant public health problem and a significant burden of morbidity and mortality in hospitals. The World Health Organization (WHO) estimates the number of daily infections to be 1 million. Currently, the number of infections and antimicrobial-resistant strains is rising. A rapid and accurate etiologic diagnosis is critical to solving this problem. In this study, we compared the STI CNM Real-Time PCR Kit using the Xpert® CT/NG technique (Cepheid®, USA) as Gold Standard for the diagnosis of Chlamydia trachomatis and Neisseria gonorrhoeae and EasyNAT® MG (Ustar Biotechnologies (Hangzhou) Ltd., China) as Gold Standard for the diagnosis of Mycoplasma genitalium infection. Regarding C. trachomatis and N. gonorrhoeae, out of 200 samples, there was a match in 199 cases, with only one positive sample not being detected by the STI CNM Real-Time PCR Kit. This results in a sensitivity of 96% and a specificity of 100% for this kit. Diagnosing M. genitalium infection, out of 200 samples, the STI CNM Real-Time PCR Kit correctly detected all negative and positive samples, with 100% agreement compared to the reference technique. In summary, the STI assay has a very high sensitivity and specificity, comparable to other commercial diagnostic kits. Furthermore, it has the advantage of bundling the detection of the three main bacterial agents of urethritis/cervicitis, resulting in better cost efficiency.

Should We Be Testing for Mycoplasma genitalium on Initial Presentation? Trends in Persistent/Recurrent Urethritis Among Men Presenting for Care in STD Clinics, 2015-2019, STD Surveillance Network

BACKGROUND

Mycoplasma genitalium is a major contributor to persistent/recurrent urethritis cases. However, there are limited published studies on recent trends of persistent/recurrent urethritis.

METHODS

A retrospective analysis was conducted of men presenting with symptomatic urethritis in 16 sexually transmitted disease (STD) clinics from 2015 to 2019. Poisson regression was used to assess trends in the annual proportions of urethritis episodes with follow-up (FU) characterized with persistent/recurrent urethritis symptoms. Results were also stratified by results of chlamydia (CT) and gonorrhea (NG) testing and treatment prescribed.

RESULTS

There were 99,897 urethritis episodes, from 67,546 unique men. The proportion of episodes with persistent/recurrent symptomatic FU visits increased 50.8% over a 4-year period (annual percentage change [APC], 11.3%; 95% confidence interval [CI], 6.5-16.3). Similar trends were observed in nonchlamydial nongonococcal urethritis episodes (APC, 12.7%; 95% CI, 6.8-18.9) but increases among those positive for NG (APC, 12.1%; 95% CI, -2.3 to -28.5) or for CT (APC, 7.3%; 95% CI, -6.7 to 23.5) were not statistically significant. Among episodes who received azithromycin as first-line treatment, increases in the proportion of persistent/recurrent FU visits were observed (APC, 12.6%; 95% CI, 8.6-16.7). For episodes where first-line treatment was doxycycline, no significant increases were detected (APC, 4.3%; 95% CI, -0.3 to 9.2).

CONCLUSIONS

We found an increase in the proportion of urethritis episodes with persistent or recurrent symptoms over time. Given these observed trends in episodes negative for NG or CT, an etiology not detectable by routine diagnostics was a likely factor in increased persistence, suggesting patients with urethritis may benefit from diagnostic testing for M. genitalium during an initial symptomatic presentation.

The Past, Present, and Future in the Diagnosis of a Neglected Sexually Transmitted Infection: Trichomoniasis

More than one million curable sexually transmitted infections occur every day. Trichomonas vaginalis is one of the main infections responsible for these epidemiological data; however, the diagnosis of this protozoan is still mainly based on microscopic and culture identification. The commercialization of immunological tests and the development of molecular techniques have improved the sensitivity of classical methods. Nevertheless, the fact that trichomoniasis is a neglected parasitic infection hinders the development of novel techniques and their implementation in routine diagnosis. This review article shows the different methods developed to identify T. vaginalis in population and the difficulties in diagnosing male and asymptomatic patients. The importance of including this parasite in routine gynecological screening, especially in pregnant women, and the importance of considering T. vaginalis as an indicator of high-risk sexual behavior are also discussed.

Mycoplasma genitalium prevalence, antimicrobial resistance-associated mutations, and coinfections with non-viral sexually transmitted infections in high-risk populations in Guatemala, Malta, Morocco, Peru and South Africa, 2019-2021

The prevalence of Mycoplasma genitalium (MG) and MG antimicrobial resistance (AMR) appear to be high internationally, however, prevalence data remain lacking globally. We evaluated the prevalence of MG and MG AMR-associated mutations in men who have sex with men (MSM) in Malta and Peru and women at-risk for sexually transmitted infections in Guatemala, South Africa, and Morocco; five countries in four WHO regions mostly lacking MG prevalence and AMR data, and estimated MG coinfections with Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG), and Trichomonas vaginalis (TV). Male urine and anorectal samples, and vaginal samples were tested for MG, CT, NG, and TV (only vaginal samples) using Aptima assays (Hologic). AMR-associated mutations in the MG 23S rRNA gene and parC gene were identified using ResistancePlus MG kit (SpeeDx) or Sanger sequencing. In total, 1,425 MSM and 1,398 women at-risk were recruited. MG was detected in 14.7% of MSM (10.0% in Malta and 20.0% Peru) and in 19.1% of women at-risk (12.4% in Guatemala, 16.0% Morocco, 22.1% South Africa). The prevalence of 23S rRNA and parC mutations among MSM was 68.1 and 29.0% (Malta), and 65.9 and 5.6% (Peru), respectively. Among women at-risk, 23S rRNA and parC mutations were revealed in 4.8 and 0% (Guatemala), 11.6 and 6.7% (Morocco), and 2.4 and 3.7% (South Africa), respectively. CT was the most frequent single coinfection with MG (in 2.6% of MSM and 4.5% of women at-risk), compared to NG + MG found in 1.3 and 1.0%, respectively, and TV + MG detected in 2.8% of women at-risk. In conclusion, MG is prevalent worldwide and enhanced aetiological MG diagnosis, linked to clinical routine detection of 23S rRNA mutations, in symptomatic patients should be implemented, where feasible. Surveillance of MG AMR and treatment outcome would be exceedingly valuable, nationally and internationally. High levels of AMR in MSM support avoiding screening for and treatment of MG in asymptomatic MSM and general population. Ultimately, novel therapeutic antimicrobials and/or strategies, such as resistance-guided sequential therapy, and ideally an effective MG vaccine are essential.

Mycoplasma genitalium infection in the female reproductive system: Diseases and treatment

Mycoplasma genitalium is a newly emerged sexually transmitted disease pathogen and an independent risk factor for female cervicitis and pelvic inflammatory disease. The clinical symptoms caused by M. genitalium infection are mild and easily ignored. If left untreated, M. genitalium can grow along the reproductive tract and cause salpingitis, leading to infertility and ectopic pregnancy. Additionally, M. genitalium infection in late pregnancy can increase the incidence of preterm birth. M. genitalium infections are often accompanied by co-infection with other sexually transmitted pathogens (Chlamydia trachomatis, Neisseria gonorrhoeae, and Trichomonas vaginalis) and viral infections (Human Papilloma Virus and Human Immunodeficiency Virus). A recent study suggested that M. genitalium plays a role in tumor development in the female reproductive system. However, few studies endorsed this finding. In recent years, M. genitalium has evolved into a new "superbug" due to the emergence of macrolide-and fluoroquinolone-resistant strains leading to frequent therapy failures. This review summarizes the pathogenic characteristics of M. genitalium and the female reproductive diseases caused by M. genitalium (cervicitis, pelvic inflammatory disease, ectopic pregnancy, infertility, premature birth, co-infection, reproductive tumors, etc.), as well as its potential relationship with reproductive tumors and clinical treatment.

2021 European guideline on the management of Mycoplasma genitalium infections

Mycoplasma genitalium infection contributes to 10-35% of non-chlamydial non-gonococcal urethritis in men. In women, M. genitalium is associated with cervicitis and pelvic inflammatory disease (PID) in 10-25%. Transmission of M. genitalium occurs through direct mucosal contact.

CLINICAL FEATURES AND DIAGNOSTIC TESTS

Asymptomatic infections are frequent. In men, urethritis, dysuria and discharge predominate. In women, symptoms include vaginal discharge, dysuria or symptoms of PID - abdominal pain and dyspareunia. Symptoms are the main indication for diagnostic testing. Diagnosis is achievable only through nucleic acid amplification testing and must include investigation for macrolide resistance mutations.

THERAPY

Therapy for M .genitalium is indicated if M. genitalium is detected. Doxycycline has a cure rate of 30-40%, but resistance is not increasing. Azithromycin has a cure rate of 85-95% in macrolide-susceptible infections. An extended course of azithromycin appears to have a higher cure rate, and pre-treatment with doxycycline may decrease organism load and the risk of macrolide resistance selection. Moxifloxacin can be used as second-line therapy but resistance is increasing.

RECOMMENDED TREATMENT

Uncomplicated M. genitalium infection without macrolide resistance mutations or resistance testing: Azithromycin 500 mg on day one, then 250 mg on days 2-5 (oral). Second-line treatment and treatment for uncomplicated macrolide-resistant M. genitalium infection: Moxifloxacin 400 mg od for 7 days (oral). Third-line treatment for persistent M. genitalium infection after azithromycin and moxifloxacin: Doxycycline or minocycline 100 mg bid for 14 days (oral) may cure 40-70%. Pristinamycin 1 g qid for 10 days (oral) has a cure rate of around 75%. Complicated M. genitalium infection (PID, epididymitis): Moxifloxacin 400 mg od for 14 days. MAIN CHANGES FROM THE 2016 EUROPEAN M.

GENITALIUM GUIDELINE

Due to increasing antimicrobial resistance and warnings against moxifloxacin use, indications for testing and treatment have been narrowed to primarily involve symptomatic patients. The importance of macrolide resistance-guided therapy is emphasised.

Molecular epidemiology and antimicrobials resistance mechanism of Mycoplasma genitlaium

Currently, infections caused by Mycoplasma genitalium are ones the most common sexually transmitted infections. Their prevalence is varied from 1.3% to 15.9%. Infections caused by M.genitalium may lead to urethritis in men and a wide spectrum of diseases in women. Antibiotic resistance now is one of the most emerging problems both in the scientific and in the healthcare fields. The usage of antimicrobials inhibiting cell wall synthesis for the treatment of M.genitalium is ineffective, and resistance to macrolides and fluoroquinolones is increasing rapidly. M.genitalium infections diagnostics is complicated due to specific conditions and duration of culture methods. The usage of nucleic acid amplification techniques is the most relevant for laboratory diagnostics, and is used in existing assays. This review compiles current data on the prevalence, molecular mechanisms of pathogenesis and antibiotic resistance, as well as diagnostics methods of M.genitalium.