Cost-effectiveness of resistance-guided therapy for Mycoplasma genitalium in Australia.

The recommended first-line treatment for Mycoplasma genitalium infections is azithromycin. However, the prevalence of macrolide resistance for M. genitalium has increased to more than 50% worldwide. In 2013, Australia introduced a resistance-guided therapy (RGT) strategy to manage M. genitalium infections. This study assesses the cost-effectiveness of the RGT approach compared to no RGT (i.e., without macrolide resistance profile test) in women, men who have sex with men (MSM), and men who have sex with women (MSW) in Australia. We constructed dynamic transmission models of M. genitalium infections in women, MSM, and MSW in Australia, each with a population of 100,000. These models compared the costs and quality-adjusted life-years (QALYs) gained between RGT and no RGT scenarios from a healthcare perspective over ten years. All costs are reported in 2022 Australian dollars (Australian $). In our model, RGT is cost saving in women and MSM, with the incremental net monetary benefit of $1.3 million and $17.9 million, respectively. In MSW, the RGT approach is not cost-effective, with an incremental cost-effectiveness ratio of -$106.96 per QALY gained. RGT is cost saving compared to no RGT for M. genitalium infections in women and MSM, supporting its adoption as the national management strategy for these two population groups.

Mycoplasmoides genitalium nucleic acid semi-quantitation and molecular macrolide resistance detection via automated assays: gender and specimen source considerations.

A laboratory-developed test (LDT) using analyte-specific reagents has been optimized on a commercial platform to detect macrolide resistance-associated mutations (MRM) in 23S rRNA from Mycoplasmoides genitalium from primary clinical specimens. In this study, MRM-LDT was applied to a multi-specimen source study set. One thousand four hundred ninety-five primary specimens testing positive for M. genitalium by commercial transcription-mediated amplification (TMA) were initially titered by the TMA assay using serial 10-fold dilutions to semi-quantitate target nucleic acid burden. Primary specimens were then processed for MRM detection using the MRM-LDT. Findings were stratified by gender and specimen source. The mean log10 target nucleic acid titer of a TMA-positive specimen was 3.51 (median 3; range 0-10). Male specimens (n = 1145) demonstrated a mean log10 M. genitalium TMA titer of 3.67; that value observed in 350 female specimens was 2.98 (P < 0.0001). The MRM-LDT detection rate (88.7%) from specimens with log10 M. genitalium TMA titers ≥ 4 was increased over specimens with log10 titers ≤ 1 (4.5%; P < 0.0002). In females, MRM-LDT was positive from 51.3% of vaginal swab and 34.7% of urine specimens (P = 0.01). In males, MRM-LDT was positive from 65.0% of rectal swab and 55.7% of urine specimens (P = 0.002). Differences were also observed in log10 M. genitalium TMA titers as a function of specimen source. M. genitalium macrolide resistance rates among multiple specimen sources, as determined by MRM-LDT, are high in the United States and can be consistent with target nucleic acid burden within the primary specimen. Caveats experienced within subgroupings support MRM reflex testing on primary M. genitalium-positive specimens. IMPORTANCE: First-line macrolide treatment failure is of increasing concern with Mycoplasmoides genitalium in multiple settings. Recent sexually-transmitted infection treatment guidelines from the United States Centers for Disease Control and Prevention have predicated therapeutic approaches on the availability of a macrolide resistance/susceptibility result from a primary clinical specimen. In this report, we investigate potential correlation between macrolide resistance mutation detection rates (identified by a molecular amplified laboratory-developed test) and transcription-mediated amplification-based rRNA target semi-quantitation. Data reveal that rRNA semi-quantitation and laboratory-developed test detection rate differences exist as a function of gender and specimen source. These data can guide providers in proper specimen selection not only for the laboratory diagnosis of M. genitalium but also macrolide resistance mutation determination from primary clinical specimens.

Azithromycin and moxifloxacin resistance determinants in Mycoplasma genitalium in Lleida, Spain.

OBJECTIVE: Mycoplasma genitalium (MG) is a microorganism related to sexually transmitted infections. Antibiotic resistance of MG leads to an increase in treatment failure rates and the persistence of the infection. The aim of this study was to describe the most frequent mutations associated with azithromycin and moxifloxacin resistance in our geographical area. METHODS: A prospective study from May 2019 to May 2023 was performed. MG-positive samples were collected. Real-time PCRs (AllplexTM MG-AziR Assay and AllplexTM MG-MoxiR Assay, Seegene) were performed in MG positive samples to detect mutations in 23S rRNA V domain and parC gene. RESULTS: A 37.1% of samples presented resistance determinants to azithromycin and the most common mutation detected was A2059G (57.9%). Resistance to moxifloxacin was studied in 72 azithromycin-resistant samples and 36.1% showed mutations, being G248T the most prevalent (73.1%). CONCLUSIONS: The resistance to different lines of treat ment suggests the need for a targeted therapy and the performing of a test of cure afterwards.

Detection of Macrolide and/or Fluoroquinolone Resistance Genes in Mycoplasma genitalium Strains Isolated from Men in the Northwest Region of Croatia in 2018-2023.

Mycoplasma genitalium (M. genitalium) poses a significant public health challenge due to its association with non-gonococcal urethritis (particularly in men) and antimicrobial resistance. However, despite the prevalence of M. genitalium infections and the rise in resistance rates, routine testing and surveillance remain limited. This is the first study from Croatia that aimed to assess the prevalence and trends of resistance in M. genitalium strains isolated from male individuals by detecting macrolide and fluoroquinolone resistance genes. The study also aimed to explore the factors associated with resistance and changes in resistance patterns over time. Urine samples collected from male individuals in the Zagreb County and northwest region of Croatia between 2018 and 2023 were tested for M. genitalium with the use of molecular methods. Positive samples were subjected to DNA extraction and multiplex tandem polymerase chain reaction (MT-PCR) targeting genetic mutations associated with macrolide (23S rRNA gene) and fluoroquinolone (parC gene) resistance. Of the 8073 urine samples tested from 6480 male individuals (and following the exclusion of repeated specimens), we found that the prevalence of M. genitalium infection was 2.2%. Macrolide resistance was observed in 60.4% of strains, while fluoroquinolone resistance was found in 19.2%. Co-resistance to both antibiotics was present in 18.2% of cases. A statistically significant increase in fluoroquinolone resistance was noted over the study period (p = 0.010), but this was not evident for azithromycin resistance (p = 0.165). There were no statistically significant differences in resistance patterns between age groups, whereas re-testing of patients revealed dynamic changes in resistance profiles over time. The high burden of macrolide resistance and increasing fluoroquinolone resistance underscore the urgent need for comprehensive resistance testing and surveillance programs. The implementation of resistance-guided treatment strategies, along with enhanced access to molecular diagnostics, is pivotal for effectively managing M. genitalium infections.

Antimicrobial treatment and resistance in sexually transmitted bacterial infections.

Sexually transmitted infections (STIs) have been part of human life since ancient times, and their symptoms affect quality of life, and sequelae are common. Socioeconomic and behavioural trends affect the prevalence of STIs, but the discovery of antimicrobials gave hope for treatment, control of the spread of infection and lower rates of sequelae. This has to some extent been achieved, but increasing antimicrobial resistance and increasing transmission in high-risk sexual networks threaten this progress. For Neisseria gonorrhoeae, the only remaining first-line treatment (with ceftriaxone) is at risk of becoming ineffective, and for Mycoplasma genitalium, for which fewer alternative antimicrobial classes are available, incurable infections have already been reported. For Chlamydia trachomatis, in vitro resistance to first-line tetracyclines and macrolides has never been confirmed despite decades of treatment of this highly prevalent STI. Similarly, Treponema pallidum, the cause of syphilis, has remained susceptible to first-line penicillin.

Epidemiología y prevalencia de Mycoplasma genitalium y resistencia a azitromicina en el Área Norte de Tenerife, Islas Canarias / Epidemiology and prevalence of Mycoplasma genitalium and resistance to azithromycin in the North Area of Tenerife, Canary Islands

INTRODUCCIÓN: La infección y resistencia antimicrobiana de Mycoplasma genitalium está infradiagnósticada en nuestra comunidad ya que no es una Enfermedad de Declaración Obligatoria y requiere técnicas de biología molecular, no siempre disponibles. OBJETIVO: Estudiar la epidemiología y prevalencia de M. genitalium y la tasa de resistencia frente a azitromicina en nuestra Área de Salud. MÉTODOS: Estudio retrospectivo, desde abril de 2019 a julio de 2020, realizado en el Área de Salud del Norte de Tenerife, la cual atiende el Hospital Universitario Canarias. Para el diagnóstico de las infecciones de transmisión sexual (ITS) se utilizó la RT-PCR Allplex™ STI Essential Assay (Seegene, South Korea). Las muestras en las que se detectó M. genitalium fueron congeladas a −80°C para posteriormente realizar estudio de resistencia a azitromicina con la RT-PCR Allplex™ MG y AziR Assay (Seegene, South Korea). RESULTADOS: Se identificaron 111/3.849 (prevalencia de 2,8%) pacientes con M. genitalium, de los cuales la mayoría, 59(53,1%) eran hombres con una mediana de 32 años (15-74) y cuyas muestras procedían principalmente de Atención Primaria: 55 (49,5%). Para la detección de resistencia a azitromicina, de los 111 pacientes solo se pudo analizar las muestras de 79, detectándose resistencia in vitro en 15(18,3%): 10 con A2059G, 4 con A2058G y 1 con ambas. La resistencia a azitromicina fue más frecuente en hombres 12 (15,8%). DISCUSIÓN Y CONCLUSIONES: Con este estudio se pone de manifiesto la importancia de la prevalencia de M. genitalium en nuestro entorno, así como su alta tasa de resistencia a azitromicina por lo que se hace necesario vigilar dicha resistencia en nuestro Área de Salud para su adecuado tratamiento.

BACKGROUND: Infection and antimicrobial resistance of Mycoplasma genitalium is under-diagnosed in our community as it is not a Notifiable Infectious Disease and requires for its detection molecular biology techniques, which are not always available. AIM: To study the epidemiology and prevalence of M. genitalium and the rate of resistance to azithromycin in our Health Care Area. METHODS: We conducted a retrospective study from April 2019 to July 2020 in the Northern Health Care Area of Tenerife, which is attended to the Universitary Hospital Complex of the Canary Islands. The RT-PCR Allplex™ STI Essential Assay (Seegene, South Korea) to diagnose Sexually Transmitted Infections (STI) was used. Samples in which M. genitalium was detected were stored at −80°C for subsequent diagnosis of resistance to azithromycin with the RT-PCR Allplex™ MG and AziR Assay (Seegene, South Korea). RESULTS: Of a total of 111/3,849 (2.8% prevalence) patients diagnosed with M. genitalium, 59 (53.1%) were male with a mean age of 30 (19-61) years and mainly from Primary Care 55 (49.5%). Only 79 samples of the 111 patients could be tested to detect azithromycin resistance, of which 15 (18.3%) were resistant in vitro: 10 with A2059G, 4 with A2058G and 1 with both. Azithromycin resistance was more frequent in men 12 (15.8%) and detected mainly in urine samples 6 (60%). Discussion and CONCLUSIONS: This study highlights the prevalence of M. genitalium in our setting as well as the high rate of resistance to azithromycin, making it necessary to detect resistance to azithromycin in M. genitalium for its appropriate treatment in our Health Care Area.

Elevada tasa de resistencia a macrólidos y fluoroquinolonas en Mycoplasma genitalium en el área sur de Tenerife / High macrolides and fluoroquinolones resistance rate in Mycoplasma genitalium in southern Tenerife

Introducción. Mycoplasma genitalium (MG) es un reconocido patógeno de transmisión sexual. El aumento de las resistencias asociadas a las principales líneas de tratamiento (macrólidos y quinolonas) justifican un estudio genético de mutaciones para mejorar las tasas de curación. Material y métodos. Un total de 8.508 muestras fueron analizadas entre abril de 2018 y julio de 2022 para la detección de MG mediante la técnica de PCR multiplex AllplexTM STI Essential Assay. En los casos positivos para MG se estudió el dominio V del gen 23S rRNA y los genes gyrA y parC. Se evaluó la importancia clínica de las mutaciones y se revisaron las historias clínicas para obtener información demográfica y de tratamiento. Resultados. Se realizó estudio de resistencias a 92 muestras (65 hombres y 27 mujeres). En lo relativo al estudio genotípico, 28 pacientes presentaban mutaciones a macrólidos (30,43%). La más habitual fue A2059G (18.48%). Para las quinolonas, 5 pacientes (5,43%) presentaron mutaciones clínicamente relevantes en el gen parC. Destaca un paciente con la mutación G295 en gyrA asociada a G248T en parC. Treinta individuos se sometieron al test de cura (TOC). La azitromicina fue el régimen empírico más común y el moxifloxacino la principal alternativa. Conclusiones. La elevada tasa de resistencias en nuestro entorno evidencia la necesidad de realizar una terapia dirigida por el estudio genotípico de resistencias a macrólidos, apoyándonos en la detección de mutaciones en parC y gyrA para predecir la susceptibilidad a quinolonas y en el uso del TOC para evaluar la respuesta al tratamiento (AU)

Introduction. Mycoplasma genitalium (MG) is a recognized sexually transmitted pathogen. Increasing resistance to main lines of treatment (macrolides and quinolones) justifies a genetic study of mutations to improve cure rates. Material and methods. A total of 8,508 samples from April 2018 to July 2022 were processed using AllplexTM STI Essential Assay. In MG positive cases 23S rRNA V domain, gyrA and parC genes were studied. Mutations detected were checked to assess their clinical significance and medical records were reviewed to obtain demographic and treatment information. Results. Resistance study was performed on 92 samples (65 men and 27 women). In relation to the genotypic study, 28 patients presented mutations to macrolides (30.43%). Most common was A2059G (18.48%). For quinolones, 5 patients (5.43%) had clinically relevant mutations in parC gene. Of note was a patient with G295 mutation in gyrA associated with G248T in parC. Thirty subjects underwent a test of cure (TOC). Azithromycin was the most common empirical regimen and moxifloxacin the main alternative. Conclusions. High rate of resistance in our environment evidences the need for targeted therapy by genotypic study of macrolide resistance, supported by the detection of mutations in parC and gyrA to predict quinolones susceptibility and the use of TOC to evaluate treatment response (AU)

Epidemiology of Mycoplasma genitalium and Trichomonas vaginalis in the primary health care setting in the Netherlands.

The aim of this paper is to describe the prevalence of Mycoplasma genitalium and Trichomonas vaginalis in patients who visited general practitioners in the Netherlands. Additionally, we describe the prevalence of M. genitalium resistance to azithromycin and moxifloxacin. We used data from 7,411 consecutive female patients who were screened for Chlamydia trachomatis, Neisseria gonorrhoeae, M. genitalium, and T. vaginalis and data from 5,732 consecutive male patients screened for C. trachomatis, N. gonorrhoeae, and M. genitalium. The prevalence of M. genitalium and T. vaginalis in female patients was 6.7% (95% CI: 6.2 to 7.4) and 1.9% (95%CI: 1.6 to 2.2%), respectively. M. genitalium prevalence in male patients was 3.7% (3.3 to 4.3). M. genitalium co-occurred with C. trachomatis in 1.4% (0.3 to 0.6%) of female and in 0.7% (0.5 to 0.9) of male patients. Macrolide resistance gene mutations and fluoroquinolone resistance gene mutations were detected in 73.8% and 9.9%, respectively. We concluded that M.genitalium is relatively infrequently found in a large general practitioner population in the Netherlands. It can co-occur with C. trachomatis, and is often resistant to azithromycin. Therefore, when treating sexually transmitted infections, these prevalence and resistance data should be taken into account.

Prevalence of Mycoplasma genitalium infection among HIV PrEP users: a systematic review and meta-analysis.

OBJECTIVES: To summarise the prevalence of Mycoplasma genitalium (MG) and antibiotic-resistant MG infection among HIV pre-exposure prophylaxis (PrEP) users. METHODS: We searched MEDLINE, Embase, Web of Science and Global Index Medicus up to 30 September 2022. We included studies reporting the prevalence of MG and/or antibiotic-resistant MG infection among PrEP users. Two reviewers independently searched for studies and extracted data. A systematic review with random-effects meta-analysis was performed to quantitatively summarise the results of included studies. The critical appraisal of included studies was conducted with the Joanna Briggs Institute checklist for prevalence studies and the quality of evidence was assessed with Grading of Recommendations Assessment, Development and Evaluation (GRADE). RESULTS: A total of 15 studies were included in the systematic review, with 2341 individuals taking PrEP. Studies were conducted in high-income level countries between 2014 and 2019. Median age of participants varied from 23.5 to 40 years. The majority were men (85%) and among them, 93% were men who have sex with men. To identify MG, urine samples were analysed in 14 studies, rectal or anal swabs in 12 studies, oral or pharyngeal swabs in 9 studies, and urethral or vaginal in 3 studies. The pooled point prevalence of MG among PrEP users was 16.7% (95% CI 13.6% to 20.3%; 95% prediction interval (95% PI) 8.2% to 31.1%). The pooled point prevalence of macrolide-resistant infections was 82.6% (95% CI 70.1% to 90.6%; 95% PI 4.7% to 99.8%) and the prevalence of fluoroquinolone-resistant infections was 14.3% (95% CI 1.8% to 42.8%). Individuals taking PrEP have a higher chance of being infected with MG compared with those not taking PrEP (OR 2.30; 95% CI 1.6 to 3.4). The quality of evidence was very low to moderate. CONCLUSION: We observed a high prevalence of MG and its macrolide resistance among PrEP users, highlighting the need to reinforce prevention strategies against sexually transmitted infections in this population. PROSPERO REGISTRATION NUMBER: CRD42022310597.

Performance of the first commercial dual resistance assay, AmpliSens Mycoplasma genitalium-ML/FQ-Resist-FL, for detection of potential macrolide and quinolone resistance-associated mutations and prevalence of M. genitalium resistance mutations in St. Petersburg, Russia.

OBJECTIVES: Antimicrobial resistance in Mycoplasma genitalium (MG) is a poorly surveyed and controlled global health concern. We evaluated the first commercial dual resistance assay, AmpliSens M. genitalium-ML/FQ-Resist-FL assay, for detection of potential macrolide and quinolone resistance-associated mutations (MRAMs and QRAMs, respectively) and estimated the prevalence of these mutations in MG in St. Petersburg, Russia. METHODS: Urogenital samples positive (n=145 from 2007 to 2020) and negative (n=56 from 2021) for MG in routine diagnostics were retrospectively analysed using the AmpliSens M. genitalium-ML/FQ-Resist-FL assay (Central Research Institute of Epidemiology, Moscow, Russia) and Sanger sequencing for validation. RESULTS: The AmpliSens M. genitalium-ML/FQ-Resist-FL assay detected potential MRAMs and QRAMs with sensitivities of 100% (CI95% 83.9 to 100) and 92.3% (CI95% 66.7 to 99.6) and specificities of 99.2% (CI95% 95.6 to 100) and 100% (CI95% 97.2 to 100), respectively, in clinical specimens with ≥1000 MG geq/mL. In total, MRAMs were detected in 13.8% (CI95% 9.1 to 20.3) of samples, with 23S rRNA A2058G being the most prevalent mutation (45.0% (CI95% 25.8 to 65.8)). QRAMs were found in 9.0% (CI95% 5.3 to 14.7) of samples, with S83I the most frequent mutation (53.8% (CI95% 29.1 to 76.8)). Dual resistance was observed in 5.5% (CI95% 2.8 to 10.5) of samples. Potential MRAM and dual resistance rates significantly increased over time: from 0% in 2007-2008 to 25% (p trend =0.0009) and 10% (p trend =0.0447), respectively, in 2018-2020. QRAM rate appeared to increase (from 0% to 13%), but significance was not reached (p trend =0.0605). CONCLUSIONS: The rapid increase in MG antimicrobial resistance in St. Petersburg, especially prominent for MRAMs, necessitates implementation of macrolide resistance-guided therapy in Russia. The first commercial dual resistance assay, AmpliSens M. genitalium-ML/FQ-Resist-FL assay, was sensitive and specific for detection of potential MRAMs and QRAMs and could be valuable in macrolide resistance-guided therapies and possibly for surveillance of QRAMs. International surveillance of antimicrobial resistance-associated mutations in MG, further research into clinical relevance of several parC mutations and novel treatments are essential.

Impact of 16S rRNA Single Nucleotide Polymorphisms on Mycoplasma genitalium Organism Load with Doxycycline Treatment.

Doxycycline targets the 16S rRNA and is widely used for the treatment of sexually transmitted infections. While it is not highly effective at eradicating Mycoplasma genitalium infections, it can reduce organism load. The aim of this study was to investigate the association between single nucleotide polymorphisms (SNPs) in the 16S rRNA gene of M. genitalium and change in organism load. M. genitalium samples were collected from 56 men prior to commencing doxycycline and at a median of 13 of 14 doses. These were sequenced for the 16S rRNA, and the association between 16S rRNA SNPs and change in organism load was determined. 16S rRNA sequences were available for 52/56 (92.9%) M. genitalium-infected men, of which 20 (38.5%) had an undetectable load, 26 (50.0%) had a decrease in M. genitalium load (median change of 105-fold), and 6 (11.5%) had an increase in load (median change of 5-fold). The most common SNPs identified were A742G (10/52 [19.2%]), GG960-961TT/C (7/52 [13.5%]), and C1435T (28/52 [53.8%]) (M. genitalium numbering). None were associated with a change in organism load (P = 0.76, 0.16, and 0.98, respectively). Using pooled published data from 28 isolates, no clear relationship between the SNPs and doxycycline MIC was identified. In conclusion, the low efficacy of doxycycline against M. genitalium does not appear to be due to variation in the 16S rRNA gene.

Single gene targeted nanopore sequencing enables simultaneous identification and antimicrobial resistance detection of sexually transmitted infections.

OBJECTIVES: To develop a simple DNA sequencing test for simultaneous identification and antimicrobial resistance (AMR) detection of multiple sexually transmitted infections (STIs). METHODS: Real-time PCR (qPCR) was initially performed to identify Neisseria gonorrhoeae (NG), Chlamydia trachomatis (CT), Mycoplasma genitalium (MG) and Trichomonas vaginalis (TV) infections among a total of 200 vulvo-vaginal swab samples from female sex workers in Ecuador. qPCR positive samples plus qPCR negative controls for these STIs were subjected to single gene targeted PCR MinION-nanopore sequencing using the smartphone operated MinIT. RESULTS: Among 200 vulvo-vaginal swab samples 43 were qPCR positive for at least one of the STIs. Single gene targeted nanopore sequencing generally yielded higher pathogen specific read counts in qPCR positive samples than qPCR negative controls. Of the 26 CT, NG or MG infections identified by qPCR, 25 were clearly distinguishable from qPCR negative controls by read count. Discrimination of TV qPCR positives from qPCR negative controls was poorer as many had low pathogen loads (qPCR cycle threshold >35) which produced few specific reads. Real-time AMR profiling revealed that 3/3 NG samples identified had gyrA mutations associated with fluoroquinolone resistance, 2/10 of TV had mutations related to metronidazole resistance, while none of the MG samples possessed 23S rRNA gene mutations contributing to macrolide resistance. CONCLUSIONS: Single gene targeted nanopore sequencing for diagnosing and simultaneously identifying key antimicrobial resistance markers for four common genital STIs shows promise. Further work to optimise accuracy, reduce costs and improve speed may allow sustainable approaches for managing STIs and emerging AMR in resource poor and laboratory limited settings.

Combination Therapy for Mycoplasma genitalium, and New Insights Into the Utility of parC Mutant Detection to Improve Cure.

BACKGROUND: Mycoplasma genitalium (MG) infection is challenging to cure because of rising antimicrobial resistance and limited treatment options. METHODS: This was a prospective evaluation of the efficacy and tolerability of resistance-guided combination antimicrobial therapy for MG treatment at Melbourne Sexual Health Centre (August 2019-December 2020). All patients received 7 days of doxycycline before combination therapy based on the macrolide-resistant profile. Macrolide-susceptible infections received combination doxycycline + azithromycin (1 g, day 1; 500 mg, days 2-4) and macrolide-resistant infections combination doxycycline + moxifloxacin (400 mg daily for 7 days). Adherence and adverse effects were recorded at test-of-cure, recommended 14-28 days after antimicrobial completion. Sequencing was performed to determine the prevalence of single nucleotide polymorphisms (SNPs) in the parC gene and their association with moxifloxacin treatment outcomes in macrolide-resistant infections. RESULTS: Of 100 patients with macrolide-susceptible MG treated with doxycycline + azithromycin, 93 were cured (93.0%; 95% confidence interval [CI], 86.1-97.1). Of 247 patients with macrolide-resistant MG receiving doxycycline + moxifloxacin, 210 were cured (85.0%; 95% CI, 80.0-89.2). parC sequencing was available for 164 (66%) macrolide-resistant infections; 29% had SNPs at parC S83 or D87 (23% S83I). The absence of SNPs at parC S83/D87 was associated with 98.3% cure (95% CI, 93.9-99.8) following doxycycline + moxifloxacin. The presence of the parC S83I-SNP was associated with failure in 62.5% (95% CI, 45.8-77.3). Side effects were common (40%-46%) and predominantly mild and gastrointestinal. CONCLUSIONS: Combination doxycycline + azithromycin achieved high cure for macrolide-susceptible infections. However, in the context of a high prevalence of the parC S83I mutation (23%) in macrolide-resistant infections, doxycycline + moxifloxacin cured only 85%. Infections that were wild-type for S83/D87 experienced high cure following doxycycline + moxifloxacin, supporting the use of a parC-resistance/susceptibility testing strategy in clinical care.

Antimicrobial resistance in Neisseria gonorrhoeae and Mycoplasma genitalium isolates from the private healthcare sector in South Africa: A pilot study.

BACKGROUND: Reports have emerged globally of antimicrobial resistance (AMR) in Neisseria gonorrhoeae and Mycoplasma genitalium infections. In South Africa (SA), there are substantial differences between private and public healthcare with regard to antimicrobial drug prescribing practice, which could affect AMR patterns of private and public healthcare patients. OBJECTIVES: To perform a pilot study to determine the frequency of AMR of N. gonorrhoeae and M. genitalium in patients accessing SA's private healthcare sector. METHODS: In this cross-sectional study, N. gonorrhoeae-positive cultures and M. genitalium DNA samples were collected from a private healthcare reference laboratory from August 2018 to August 2019. In N. gonorrhoeae-positive cultures, antimicrobial susceptibility testing was performed, followed by N. gonorrhoeae multiantigen sequence typing (NG-MAST) to determine genetic relatedness of the isolates. To determine macrolide and fluoroquinolone resistance rates, M. genitalium-positive samples were analysed by sequencing the 23S rRNA, gyrA and parC genes. RESULTS: Twenty-one N. gonorrhoeae- and 27 M. genitalium-positive specimens were included in this analysis. High rates of resistance were detected among gonococcal isolates, with 90% resistance to tetracycline, 86% to penicillin and 62% to ciprofloxacin, but no resistance to azithromycin, cefixime and ceftriaxone. NG-MAST revealed genetically diverse isolates with 83% novel NG-MAST sequence types. Macrolide and fluoroquinolone resistance-associated mutations were detected in 18.5% (n=5/27) and 7.4% (n=2/27) of M. genitalium strains, respectively. CONCLUSIONS: We observed high frequencies of ciprofloxacin, penicillin and tetracycline resistance in N. gonorrhoeae and macrolide resistance-associated mutations in M. genitalium in private healthcare sector patients in SA. This finding highlights the need to use diagnostics for sexually transmitted infections and to include the private healthcare sector in antimicrobial surveillance and stewardship programmes.

Molecular mechanisms of macrolide and fluoroquinolone resistance among Korean isolates of Mycoplasma genitalium over a period of five years 2014-2019.

Antimicrobial resistance in Mycoplasma genitalium has become a global issue, and certain groups have a higher probability of acquiring resistant strains. Little is known about the genetic diversity and characteristics of the antimicrobial resistance-determining sites (ARDSs) of M. genitalium in the Korean population. Therefore, we examined the genetic diversity of the ARDSs of M. genitalium-positive urogenital samples obtained from Korean females (G1) and males (G2) visiting primary care clinics and DNA samples from referred males (G3) with persistent urethritis. From 2014 to 2019, 54 patients from G1, 86 patients from G2, and 68 patients from G3 were included in the study. Sanger sequencing was performed on the 2058/2059 sites in the 23S rRNA gene and quinolone resistance-determining regions (QRDRs) of M. genitalium. The rates of mutation in G1, G2, and G3 were 1.85, 5.81, and 48.53 %, respectively, for A2059G in the 23S rRNA gene (P<0.001); 1.85, 0, and 17.78 %, respectively, for M95R or I in gyrA (P<0.001); 0, 0, and 31.11 %, respectively, for D99N or G in gyrA (P<0.001); and 7.41, 16.28, and 30 %, respectively, for S83R or N or I in parC (P=0.015). A2059G significantly increased the risk of mutations at the gyrA95, gyrA99, and parC83 sites (all P<0.01). In conclusion, although the genetic diversity of the ARDSs of M. genitalium was variable among the groups, it was generally lower in isolates with macrolide resistance and higher in isolates with quinolone resistance in Korea compared with the isolates in other countries. The G3 group demonstrated increased genetic diversity at the A2059G, gyrA95, gyrA99, and parC83 sites.

Mycoplasma genitalium prevalence and macrolide resistance-associated mutations and coinfection with Chlamydia trachomatis in Southern Jutland, Denmark.

This study aims to investigate prevalence of Mycoplasma genitalium and macrolide resistance-associated mutations and coinfection with other sexually transmitted bacteria in Southern Jutland, Denmark, where this information is very limited. Urinary samples from patients suspected of sexually transmitted bacterial infections collected at primary healthcare facilities in Southern Jutland are routinely tested for Chlamydia trachomatis and Neisseria gonorrhoeae. 601 of these samples were analysed with SpeeDx MG+23S reagents, which can detect M. genitalium and macrolide resistance-mediating mutations in the 23S rRNA gene. Moreover, 147 C. trachomatis positive urinary samples from routine test were also analysed with the PCR assay to detect M. genitalium. 72 out of 601 samples were detected positive for C. trachomatis (12%), five samples (0.83%) positive for N. gonorrhoeae and 25 samples positive for M. genitalium (4.2%). 14 of the 25 M. genitalium samples were detected having 23S rRNA gene mutations associated with macrolide resistance (56%). 25 of 147 C. trachomatis positive samples were tested positive for M. genitalium (17%) and two of them were positive for M. genitalium and N. gonorrhoeae (1.4%). The high prevalence of M. genitalium and macrolide resistance-associated mutation and the coinfection with C. trachomatis in the region suggesting that M. genitalium testing should be included in routine sexually transmitted infection screening.

Prevalence of Mycoplasma genitalium fluoroquinolone-resistance markers, and dual-class-resistance markers, in asymptomatic men who have sex with men.

Introduction. Failure of fluoroquinolones, the principal treatment option for macrolide-resistant Mycoplasma genitalium infections, has recently emerged. This is of particular concern for men who have sex with men (MSM), who have high proportions of macrolide-resistant M. genitalium infections. Treatment failure with moxifloxacin is likely the result of single nucleotide polymorphisms (SNPs) in parC, whilst concurrent gyrA mutations may play a role.Gap Statement. The levels of fluoroquinolone resistance and dual-class (i.e. macrolide and fluoroquinolone) resistance in M. genitalium among asymptomatic MSM is unknown.Aim. To (i) determine the proportion of fluoroquinolone resistance and dual-class resistance in M. genitalium infections among asymptomatic MSM, (ii) explore any clinical and behavioural associations with fluoroquinolone resistance, and (iii) determine the distribution of antibiotic resistance among M. genitalium mgpB sequence types (STs).Methodology. M. genitalium positive samples (N=94) were obtained from 1001 asymptomatic MSM enrolled in a study at Melbourne Sexual Health Centre (Carlton, Australia) between August 2016 and September 2017. Sanger sequencing was performed to determine the proportion of M. genitalium infections with SNPs in parC that have previously been associated with failure of moxifloxacin (corresponding to amino changes S83I, D83R, D87Y and D87N) and in gyrA (corresponding to amino acid changes M95I, D99N, D99Y and D99G). Associations between clinical/behavioural factors and parC SNPs were examined. Strain typing was performed by sequencing a portion of the mgpB gene.Results. The proportion of MSM with infections harbouring parC and gyrA SNPs was 13.0 % [95 % confidence interval (CI): 6.8-23.2 %] and 4.7 % (95 % CI: 1.1-13.4 %), respectively; dual-class resistance was 13.0 %. No significant clinical/behavioural associations were found. Antibiotic resistance was not restricted to specific mgpB STs.Conclusion. One in eight (13 %) of asymptomatic MSM with M. genitalium had an infection with dual-class-resistance mutations. Typing by mgpB sequence suggested fluoroquinolone resistance is arising from independent mutation events. This study illustrates that asymptomatic MSM may act as a reservoir for antibiotic-resistant M. genitalium.