Prevalence of Mycoplasma genitalium and Antibiotic Resistance-Associated Mutations in Patients at a Sexually Transmitted Infection Clinic in Iceland, and Comparison of the S-DiaMGTV and Aptima Mycoplasma genitalium Assays for Diagnosis

Genetic Determinants of Macrolide and Fluoroquinolone Resistance in Mycoplasma genitalium and Their Prevalence in Moscow, Russia

Macrolide (MLR) and fluoroquinolone (FQR) resistance in Mycoplasma genitalium (MG) has recently become a major problem worldwide. The available data on the prevalence of MLR and FQR in MG in Russia are limited. In this study, we aimed to evaluate the prevalence and pattern of mutations in 213 MG-positive urogenital swabs from patients in Moscow between March 2021 and March 2022. MLR- and FQR-associated mutations were searched in 23S rRNA as well as in the parC and gyrA genes using Sanger sequencing. The prevalence of MLR was 55/213 (26%), with A2059G and A2058G substitutions being the two most common variants (36/55, 65%, and 19/55, 35%, respectively). FQR detection showed 17% (37/213); two major variants were D84N (20/37, 54%) and S80I (12/37, 32.4%) and three minor variants were S80N (3/37, 8.1%), D84G (1/37, 2.7%), and D84Y (1/37, 2.7%). Fifteen of the fifty-five MLR cases (27%) simultaneously harbored FQR. This study revealed the high frequency of MLR and FQR. We conclude that the improvement of patient examination algorithms and therapeutic approaches should be combined with the routine monitoring of antibiotic resistance based on the sensitivity profiles presented. Such a complex approach will be essential for restraining the development of treatment resistance in MG.

Development of a Real-Time PCR Assay for Detection of Macrolide Resistance Mutations in Mycoplasma genitalium and Its Application for Epidemiological Surveillance in Russia

A real-time PCR assay based on probe fluorescence quenching by a primer was developed and validated for detection of macrolide resistance (MR)-associated mutations in the 23S rRNA gene of Mycoplasma genitalium. The assay involves identification of any nucleotide substitutions at positions 2058, 2059, and 2611 of 23S rRNA (Escherichia coli numbering) by the probe-based melting curve analysis immediately after amplification and was capable of detecting target mutations in clinical specimens and spiked samples with 92% sensitivity and 100% specificity. We applied this new assay to assess the prevalence of MR-associated mutations in 949 nonduplicate urogenital samples positive for M. genitalium by routine diagnostic PCR, which were collected from symptomatic patients in five cities in the European part of Russia during the period 2009-2019. Forty-three (4.92%) samples revealed the presence of MR mutations, and no trend toward an increase in resistance prevalence was observed over the 10-year period of the study. The most commonly detected mutations were A2058G (26/43; 60.47%) and A2059G (13/43; 30.23%), while other mutations were rare: A2058T (3/43; 6.98%) and C2611T (1/43; 2.33%). The data obtained underline the need for regular epidemiological monitoring to ensure effective patient management, rational use of antibiotics, and prevention of further spread of resistance.

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.

Nanomedicines for the topical treatment of vulvovaginal infections: Addressing the challenges of antimicrobial resistance

Recent years have, surprisingly, witnessed an increase in incidence of sexually transmitted infections (STIs). At the same time, antimicrobial therapy came under the threat of ever rising antimicrobial resistance (AMR), resulting in STIs with extremely limited therapy options. In this review, we addressed the challenges of treating vaginal infections in an era of AMR. We focused on published work regarding nanomedicine destined for localized treatment of vaginal infections. Localized therapy offers numerous advantages such as assuring high drug concentration at the infection site, limiting systemic drug exposure that can lead to faster development of AMR reduction in the systemic side effects and potentially safe therapy in pregnancy. We provided a state-of-the-art overview of nanoformulations proposed to topically treat STIs, emphasizing the challenges and advantages of each type of nanocarriers, as well as issues of potential toxicity.

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.

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

INTRODUCTION

Mycoplasma genitalium (MG) causes frequently asymptomatic STIs. MG prevalence figures are lacking and management is complicated by the lack of etiological diagnostics and high antimicrobial resistance in many countries. Appropriately validated, quality-assured, and FDA-approved MG diagnostic assays have been lacking.

AREAS COVERED

The clinical and analytical performance characteristics of the Aptima® MG assay, the first FDA-approved MG nucleic acid amplification test (NAAT), are summarized. Key priorities in the management and control of MG infections are also discussed.

EXPERT OPINION

Highly sensitive, specific, and quality-assured MG NAATs, e.g. the Aptima MG assay on the automated and flexible Panther® platform, are imperative to improve the management and control of MG infections internationally. This testing, combined with macrolide-resistance testing (not yet available on the Panther platform), offers a rapid, high-throughput, and appropriate diagnosis of MG. Macrolide resistance-guided sequential treatment needs to be implemented for MG infections. Dual antimicrobial therapy, novel antimicrobials and, ideally, a vaccine may become essential.