Macrolide Resistance In Mycoplasma Genitalium Research Articles

Low prevalence of macrolide resistance in Mycoplasma genitalium infections in a cohort of pregnant women living with human immunodeficiency virus.

Macrolide resistance in Mycoplasma genitalium (M. genitalium) is increasing as a result of the widespread use of azithromycin in the treatment of sexually transmitted infections (STIs). To date, there are few published studies on macrolide resistance patterns in South African pregnant women. This study now contributes to the growing body of knowledge. This study included 385 pregnant women living with HIV. Vaginal swabs were collected from consenting pregnant women and used for the detection of M. genitalium using the TaqMan assay. Macrolide resistance-associated mutations in the 23S rRNA gene were determined for all samples that tested positive for M. genitalium using the AllplexTM MG & AziR assay (Seegene) which allows for the simultaneous detection and identification of M. genitalium and six mutations (A2058C, A2058G, A2058T, A2059C, A2059G and A2059T) responsible for azithromycin resistance. The correlation between the TaqMan assay and AllplexTM MG & AziR assay (Seegene) for the detection of M. genitalium was also performed in a subset of 121 samples. Of the 385 samples tested in this study, 14 samples were positive for M. genitalium estimating a prevalence of 3.6%. The same 14 samples also tested positive on the AllplexTM assay indicating a good correlation between the TaqMan Assay and the AllplexTM. Of the 14 positive samples, one sample carried a mutation at position A2059G denoting macrolide resistance in this pathogen. Mutations in the other regions of the 23S rRNA were not detected. All assay controls used in the mutation scanning produced the desired results showing the validity of the assay. In this study, macrolide resistance in M. genitalium was detected. Despite the low prevalence of resistance determinants ongoing antimicrobial resistance surveillance is vital considering that azithromycin is used in the syndromic management for the treatment of vaginal discharge syndrome.

Distribution of Macrolide Resistant Mycoplasma genitalium in Urogenital Tract Specimens From Women Enrolled in a US Clinical Study Cohort.

This study evaluated the distribution of macrolide-resistant Mycoplasma genitalium in multiple urogenital specimens collected from women enrolled in a prospective multicenter US clinical study. Four female urogenital specimens (vaginal swab, urine, endocervical swab, ectocervical brush/spatula) collected from each subject were tested using a transcription-mediated amplification (TMA) assay for M. genitalium. TMA-positive specimens were evaluated by reverse transcription-polymerase chain reaction and bidirectional Sanger sequencing of M. genitalium 23S rRNA to identify the presence of macrolide-resistance-mediating mutations (MRMs) at base positions 2058/2059. Of 140 women with ≥1 TMA-positive specimens, 128 (91.4%) yielded M. genitalium 23S rRNA sequence. MRMs were found in 52% of vaginal specimens, 46.3% of urine specimens, 37.8% of endocervical specimens, and 46% of ectocervical specimens. There were 44 unique specimen type/sequence phenotype combinations of M. genitalium infection. Most (81; 63.3%) women had single specimen-sequence phenotype (macrolide-susceptible, MRM, or both) infections, while 24 (18.8%) women had multiple specimen-sequence phenotype concordant infections, and 23 (17.9%) women had multiple specimen-sequence phenotype discordant infections. The sensitivity for any single specimen type to detect overall urogenital tract macrolide-resistant M. genitalium infection status was 96.3% for vaginal swab samples, 82.6% for urine samples, 70.8% for endocervical swab samples, and 82.1% for ectocervical brush/spatula liquid Pap samples. The distribution of M. genitalium infections in female urogenital tract specimens is highly complex, with multiple phenotypic combinations of the organism infecting a significant proportion of women at different anatomic specimen collection sites. Vaginal swab sampling yielded the highest sensitivity for identifying women with macrolide-resistant M. genitalium urogenital tract infections.

ParC Variants in Mycoplasma genitalium: Trends over Time and Association with Moxifloxacin Failure.

Prevalence, trends, and treatment outcome estimates were generated for parC variants in macrolide-resistant Mycoplasma genitalium. Among 539 cases, the most common amino acid change was S83I, which increased from 13% in 2012 to 2013, to 23% in 2019 to 2020 (Ptrend = 0.046). From 381 moxifloxacin treatments, failure occurred in 58.7% (95% confidence interval [CI], 46.7 to 69.9) of cases with S83I. Other changes affecting S83 or D87 were uncommon and minor contributors to failure. The absence of S83I was highly predictive of moxifloxacin cure (96.4%; 95% CI, 93.7 to 98.2), highlighting diagnostic potential.

Prevalence of Mycoplasma Genitalium Infection and Resistance in Pregnant Women

Mycoplasma genitalium (MG) infection is a sexually transmitted bacterial infection that causes cervicitis and has been associated with pelvic inflammatory disease. Gaps in knowledge or areas of conflicting data among pregnant women include: MG infection prevalence (∼1%-18%), rates of MG macrolide resistance, and importantly, the effect of MG infection on pregnancy outcomes. The goal of this study was to estimate the prevalence of MG infection and associated macrolide resistance among pregnant women attending an urban healthcare center.

Macrolide resistance in Mycoplasma genitalium in Catalonia, Spain: a 1 year prospective study.

Mycoplasma genitalium is an emergent cause of sexually transmitted disease (STD). The first-line treatment is azithromycin, but macrolide resistance is increasing due to mutations in the 23S rRNA gene. To determine the rates of M. genitalium infection and macrolide resistance in an area adjacent to Barcelona. This 1 year prospective study was performed in a heterogenous population that included both low- and high-risk patients. M. genitalium was detected in all specimens sent to our institution for STD detection. Epidemiological and relevant clinical data were collected in the positive cases. Characterization of macrolide-associated resistance was performed by 23S rDNA sequencing. Of the 3540 patients included, 132 (3.7%) were positive for M. genitalium. Another sexually transmitted bacteria was detected in 20.4% of the M. genitalium cases, and Chlamydia trachomatis (11%) was the most frequently co-detected microorganism. Only 61.4% of patients received an adequate initial treatment against M. genitalium. The test of cure (TOC) was performed in 42% of patients, and therapeutic failure was detected in 10 cases. The rate of macrolide resistance was 12.6% and the most prevalent mutation was A2058G. There was an association between macrolide resistance and a previous history of M. genitalium detection (P < 0.001). Our results support the contribution of the previous use of macrolides in resistant strains. Given the difficulties in performing TOC in all patients, the inclusion of macrolide resistance in the detection test should be mandatory.

The clinical indications for testing women for Mycoplasma genitalium

BackgroundWhile 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...

Impact of screening on the prevalence and incidence of Mycoplasma genitalium and its macrolide resistance in men who have sex with men living in Australia: A mathematical model.

BackgroundMycoplasma genitalium (MG) causes a sexually transmitted infection (STI) with a rising rate of antimicrobial resistance. Currently, guidelines do not recommend screening asymptomatic men who have sex with men (MSM). We developed a mathematical model of MG transmission to examine the impact of various screening strategies on the incidence and prevalence of MG among MSM attending a sexual health clinic.MethodsA compartmental mathematical model of MG transmission among MSM was constructed and calibrated using data from the Melbourne Sexual Health center, where resistance-guided therapy provides high treatment effectiveness (92–95%). The model stratified men by symptom status, sexual risk behaviours and whether or not they had MG with macrolide resistance. We simulated the impact on endemic steady-state MG prevalence and incidence of the following screening scenarios, namely screening: 1) no MSM; 2) only symptomatic MSM (the current recommendation); 3) all symptomatic and high-risk asymptomatic MSM; and 4) all MSM. Our base case analysis assumed a treatment effectiveness of 92–95% using resistance-guided therapy. We also examined the impact of treatment effectiveness (i.e. the proportion of detected MG that were cured) and screening coverage (i.e. testing rate) on MG prevalence.FindingsThe model predicts that the overall endemic MG prevalence is 9.1% (95% CI: 7.9–10.0) in the current situation where screening is only offered to symptomatic MSM (base-case). This would increase to 11·4% (95% confidence intervals (CI): 10.2–13.7) if no MSM are offered screening, but would decrease to 7.3% (95% CI: 5.7–8.4) if all symptomatic and high-risk asymptomatic MSM were offered screening and 6.4% (95% CI: 4.7–7·7) if all MSM were offered screening. Increasing coverage of MSM screening strategies shows a similar effect on decreasing endemic MG incidence. When evaluating the simultaneous impact of treatment effectiveness and screening coverage, we found that offering screening to more MSM may reduce the overall prevalence but leads to a higher proportion of macrolide-resistant MG, particularly when using treatment regimens with lower effectiveness.InterpretationBased on the available treatment options, offering screening for MG to other MSM (beyond the currently recommended group of symptomatic MSM) could slightly reduce the prevalence and incidence of MG. However, further increasing screening coverage must be weighed against the impact of lower treatment effectiveness (i.e. when not using resistance-guided therapy), increasing the selection of macrolide resistance, and other negative consequences related to AMR and management (e.g. unnecessary psychological morbidity from infections that do not need treatment).

Comparison of three real-time PCR methods for detection of macrolide-resistant Mycoplasma genitalium in Sweden

There is a worldwide increase in macrolide-resistant Mycoplasma genitalium strains, with severe impacts on treatment. The aim of this study was to compare three real-time PCR methods for the detection of macrolide resistance: an in-house PCR described by Touati et al., ResistancePlus® MG (SpeeDx), and S-DiaMGRes™ (Diagenode Diagnostics). One hundred M. genitalium-positive patient samples collected in Sweden and a quantitated M. genitalium DNA control were analyzed. Macrolide resistance was detected in 18, 15, and 16 of the samples with the respective methods. Sequencing of the 23S rRNA gene confirmed resistance in 16 (16%) of 100 samples in which it was detected with any of the three methods. ResistancePlus® MG and S-DiaMGRes™ falsely determined one sample as macrolide-sensitive, but this sample was determined as resistant when retested. The sensitivity of the methods was comparable, although there should be awareness of possible incorrect determination of macrolide resistance, especially of low-positive samples.

Evaluating the prevalence and risk factors for macrolide resistance in Mycoplasma genitalium using a newly developed qPCR assay.

Mycoplasma genitalium (MG) is a sexually transmitted bacterium in which macrolide resistance is rapidly increasing, limiting treatment options. We validated a new assay to detect the presence of macrolide resistance-associated mutations in MG (MG-MRAM). In 2018, symptomatic and asymptomatic clients visiting sexually transmitted infections (STI) clinics in Amsterdam or The Hague were tested for MG using transcription mediated amplification (TMA) assays. The sensitivity to detect MG of the newly developed MG-MRAM qPCR was compared to the MgPa qPCR, both in relation to the TMA assay. For the sensitivity and specificity to detect relevant mutations the MG-MRAM qPCR was compared to 23SrRNA sequencing analysis. The qPCR was subsequently used to determine the presence of MG-MRAM at different anatomical locations and to identify risk factors for MG-MRAM. MG-positive clients (402) providing 493 MG-positive samples were included. In total 309/493 (62.7%) samples from 291 (72.4%) clients were successfully typed with the MG-MRAM qPCR. The MG-MRAM qPCR had a sensitivity of 98.6% (95%CI 91.1%-99.9%) and specificity of 94.1% (95%CI 78.9%-99.0%) to detect MG-MRAM compared to sequencing analysis. Infection with MG-MRAM was detected in 193/291 (66.3%) clients: in 129/178 (72.5%) men and 64/113 (56.6%) women (p = 0.005). Prevalence of MG-MRAM was significantly higher in men, clients with a higher education, HIV-positive clients and clients with >10 sexual partners in the previous six months, but in multivariable analysis no factor was significantly associated with MG-MRAM presence. Since MG-MRAM prevalence was very high, testing for MG-MRAM is essential if treatment for MG is considered, and can be performed with this sensitive and specific qPCR test in routine diagnostics.

Molecular detection of Mycoplasma genitalium in endocervical swabs and associated rates of macrolide and fluoroquinolone resistance in Hong Kong.

There is a global trend of increasing macrolide and fluoroquinolone resistance in Mycoplasma genitalium (MG), such that international guidelines recommend molecular detection of resistance if a patient has MG-positive test results. Tests for MG are not routinely performed in Hong Kong. This study examined the detection of MG in endocervical swabs and the associated macrolide and fluoroquinolone resistance rates. Endocervical swabs received from two sexual health clinics in Hong Kong for routine assessments of Chlamydia trachomatis and Neisseria gonorrhoeae were also subjected to detection of MG. All MG-positive samples were tested for resistance-mediating mutations in 23S rRNA, parC, and gyrA genes. Laboratory records and past results for each patient were analysed. In total, endocervical swabs from 285 patients were included in this study. Mycoplasma genitalium was detected in swabs from 21 patients (7.4%) by real-time polymerase chain reaction with a commercial kit. Among MG-positive samples which were successfully analysed further, macrolide resistance-mediating mutations in 23S rRNA were found in 42.1% (8/19); fluoroquinolone resistance-related mutations in parC and gyrA were found in 65% (13/20) and 0% (0/20), respectively. All macrolide-resistant MG strains were also fluoroquinolone-resistant (42.1%, 8/19). No assessed factors were associated with the detection of MG or resistance-related mutations. In Hong Kong, MG was detected in endocervical swabs from 7.4% of patients in sexual health clinics, with high rates of macrolide and fluoroquinolone resistance. These findings warrant careful review of testing, clinical correlation, and treatment strategies for MG in the context of increasing antibiotic resistance.

High prevalence of coinfection of azithromycin-resistant Mycoplasma genitalium with other STIs: a prospective observational study of London-based symptomatic and STI-contact clinic attendees

ObjectivesAzithromycin treatment of Chlamydia trachomatis (CT) may not be adequate to treat concomitant Mycoplasma genitalium (MG) infection, and particularly if MG has macrolide resistance-associated mutations (MG-MRAMs). We estimated prevalence of...

High Prevalence of Vaginal and Rectal Mycoplasma genitalium Macrolide Resistance Among Female Sexually Transmitted Disease Clinic Patients in Seattle, Washington.

Rectal Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (GC) are increasingly recognized as common infections among women. Little is known about the prevalence of rectal Mycoplasma genitalium (MG), rectal MG/CT/GC coinfection, or MG antimicrobial resistance patterns among women. In 2017 to 2018, we recruited women at high risk for CT from Seattle's municipal sexually transmitted disease clinic. Participants self-collected vaginal and rectal specimens for CT/GC nucleic acid amplification testing. We retrospectively tested samples for vaginal and rectal MG using nucleic acid amplification testing and tested MG-positive specimens for macrolide resistance-mediating mutations (MRM) and ParC quinolone resistance-associated mutations (QRAMs). Of 50 enrolled women, 13 (26%) tested positive for MG, including 10 (20%) with vaginal MG and 11 (22%) with rectal MG; 8 (62%) had concurrent vaginal/rectal MG. Five (38%) were coinfected with CT, none with GC. Only 2 of 11 women with rectal MG reported anal sex in the prior year. Of MG-positive specimens, 100% of rectal and 89% of vaginal specimens had an MRM. There were no vaginal or rectal MG-positive specimens with ParC QRAMs previously associated with quinolone failure. Five MG-infected women received azithromycin for vaginal CT, 4 of whom had a MG MRM detected in their vaginal and/or rectal specimens. We observed a high prevalence of macrolide-resistant vaginal and rectal MG among a population of women at high risk for CT. This study highlights how the use of antimicrobials designed to treat an identified infection-in this case, CT-could influence treatment outcomes and antimicrobial susceptibility in other unidentified infections.

Understanding the spread of de novo and transmitted macrolide-resistance in Mycoplasma genitalium.

BackgroundThe rapid spread of azithromycin resistance in sexually transmitted Mycoplasma genitalium infections is a growing concern. It is not yet clear to what degree macrolide resistance in M. genitalium results from the emergence of de novo mutations or the transmission of resistant strains.MethodsWe developed a compartmental transmission model to investigate the contribution of de novo macrolide resistance mutations to the spread of antimicrobial-resistant M. genitalium. We fitted the model to resistance data from France, Denmark and Sweden, estimated the time point of azithromycin introduction and the rates at which infected individuals receive treatment, and projected the future spread of resistance.ResultsThe high probability of de novo resistance in M. genitalium accelerates the early spread of antimicrobial resistance. The relative contribution of de novo resistance subsequently decreases, and the spread of resistant infections in France, Denmark and Sweden is now mainly driven by transmitted resistance. If treatment with single-dose azithromycin continues at current rates, macrolide-resistant M. genitalium infections will reach 25% (95% confidence interval, CI [9–30]%) in France, 84% (95% CI [36–98]%) in Denmark and 62% (95% CI [48–76]%) in Sweden by 2025.ConclusionsBlind treatment of urethritis with single-dose azithromycin continues to select for the spread of macrolide resistant M. genitalium. Clinical management strategies for M. genitalium should limit the unnecessary use of macrolides.

Mycoplasma genitalium macrolide resistance update: Rate among a 2016–2017 cohort of patients in Barcelona, Spain

IntroductionMycoplasma genitalium is a major cause of urethritis and other genital syndromes. Antibiotic resistance, especially to macrolides, is increasing at an alarming rate worldwide. The aim of this study was to estimate the rate of macrolide resistance in M. genitalium among a 2016–2017 cohort of patients in Barcelona, Spain; and to compare this estimate with previous data from 2013 to 2014 in this region. MethodsThe study was conducted retrospectively with M. genitalium-positive samples collected between December 2016 and February 2017 at the Hospital Vall d’Hebron Microbiology Department. Genotypic markers of macrolide resistance were primarily detected using the ResistancePlus® MG molecular assay (SpeeDx). Mutations were then confirmed by sequencing. ResultsMacrolide resistance-mediating mutations were detected in 30/83 infections (36.1% [95% CI, 25.9%–47.4%]). This resistance was more frequent among men who have sex with men (55.0% [95% CI, 38.5%–70.7%]) compared to heterosexual men (27.3% [95% CI, 10.7%–50.2%]) and women (9.5% [95% CI, 1.3%–30.4%]), p<0.001. Additionally, macrolide resistance did not significantly increase in this cohort when compared with previous investigations. ConclusionDespite the current notable rate of macrolide resistance in M. genitalium, resistance did not significantly increase between 2013–2014 and 2016–2017 in our region. Nevertheless, strict local surveillance and the implementation of rapid diagnostic tests that combine the detection of the bacterium and resistance-mediating mutations may facilitate the optimization of antibiotic administration and reduce the transmission of resistance in M. genitalium.

Resistance-Guided Antimicrobial Therapy Using Doxycycline-Moxifloxacin and Doxycycline-2.5 g Azithromycin for the Treatment of Mycoplasma genitalium Infection: Efficacy and Tolerability.

Macrolide resistance in Mycoplasma genitalium (MG) exceeds 50% in many regions, and quinolone resistance is increasing. We recently reported that resistance-guided therapy (RGT) using doxycycline followed by sitafloxacin or 2.5 g azithromycin cured 92% and 95% of macrolide-resistant and macrolide-susceptible infections, respectively. We present data on RGT using doxycycline-moxifloxacin, the regimen recommended in international guidelines, and extend data on the efficacy of doxycycline-2.5 g azithromycin and de novo macrolide resistance. Patients attending Melbourne Sexual Health Centre between 2017 and 2018 with sexually transmitted infection syndromes were treated with doxycycline for 7 days and recalled if MG-positive. Macrolide-susceptible cases received 2.5 g azithromycin (1 g, then 500 mg daily for 3 days), and resistant cases moxifloxacin (400 mg daily, 7 days). Test of cure was recommended 14-28 days post-antimicrobials. There were 383 patients (81 females/106 heterosexual males/196 men who have sex with men) included. Microbial cure following doxycycline-azithromycin was 95.4% (95% confidence interval [CI], 89.7-98.0) and doxycycline-moxifloxacin was 92.0% (95% CI, 88.1-94.6). De novo macrolide resistance was detected in 4.6% of cases. Combining doxycycline-azithromycin data with our prior RGT study (n = 186) yielded a pooled cure of 95.7% (95% CI, 91.6-97.8). ParC mutations were present in 22% of macrolide-resistant cases. These findings support the inclusion of moxifloxacin in resistance-guided strategies and extend the evidence for 2.5 g azithromycin and presumptive use of doxycycline. These data provide an evidence base for current UK, Australian, and European guidelines for the treatment of MG.

Four-color multiplex real-time PCR assay prototype targeting azithromycin resistance mutations in Mycoplasma genitalium

BackgroundThe worldwide expansion of macrolide-resistant Mycoplasma genitalium (MG) in cases of genital infections has led to an increased recurrence rate of these infections after first-line azithromycin treatment. By detecting the presence of azithromycin-resistant MG, the patient’s antibiotic treatment can be targeted and the spread of resistance prevented. With this aim in mind, macrolide-resistance detection kits are helpful tools for the physician.MethodsAzithromycin resistance mutations in MG are targeted using a four-color multiplex real-time RT-PCR assay. Tested targets include plasmid DNA (as positive controls) as well as macrolide-sensitive and macrolide-resistant genomic DNA from characterized cell lines and clinical samples.ResultsThe analytical data presented here were generated from plasmid DNA and genomic RNA/DNA and include adaptation to an internal control, specificity between targets, specificity vs non-MG species, limit of detection (LoD) and interference studies (co-infection and endogenous substances). The clinical data were based on the application of the assay to clinical samples characterized by sequencing.ConclusionsA new NAAT (nucleic acid amplification test) prototype has been developed in collaboration with the Diagenode s.a. company, this prototype targets MG and azithromycin-resistance mutations in that pathogen.

Mycoplasma genitalium macrolide resistance update: Rate among a 2016–2017 cohort of patients in Barcelona, Spain

IntroductionMycoplasma genitalium is a major cause of urethritis and other genital syndromes. Antibiotic resistance, especially to macrolides, is increasing at an alarming rate worldwide. The aim of this study was to estimate the rate of macrolide resistance in M. genitalium among a 2016–2017 cohort of patients in Barcelona, Spain; and to compare this estimate with previous data from 2013 to 2014 in this region. MethodsThe study was conducted retrospectively with M. genitalium-positive samples collected between December 2016 and February 2017 at the Hospital Vall d’Hebron Microbiology Department. Genotypic markers of macrolide resistance were primarily detected using the ResistancePlus® MG molecular assay (SpeeDx). Mutations were then confirmed by sequencing. ResultsMacrolide resistance-mediating mutations were detected in 30/83 infections (36.1% [95% CI, 25.9%–47.4%]). This resistance was more frequent among men who have sex with men (55.0% [95% CI, 38.5%–70.7%]) compared to heterosexual men (27.3% [95% CI, 10.7%–50.2%]) and women (9.5% [95% CI, 1.3%–30.4%]), p<0.001. Additionally, macrolide resistance did not significantly increase in this cohort when compared with previous investigations. ConclusionDespite the current notable rate of macrolide resistance in M. genitalium, resistance did not significantly increase between 2013–2014 and 2016–2017 in our region. Nevertheless, strict local surveillance and the implementation of rapid diagnostic tests that combine the detection of the bacterium and resistance-mediating mutations may facilitate the optimization of antibiotic administration and reduce the transmission of resistance in M. genitalium.

Macrolide-resistant Mycoplasma genitalium in male and female patients attending a Northern Irish Genitourinary Medicine Clinic

Background Mycoplasma genitalium (MG) can cause urethritis in men and pelvic inflammatory disease in women. Despite the increasing rate of MG resistance to first-line macrolide treatment due to 23S rRNA gene mutations, the availability of testing remains limited in UK laboratories. This study obtained preliminary data on the rate of macrolide resistant strains circulating in N. Ireland. Methods Clinical specimens from 1052 patients attending a Genitourinary Medicine (GUM) clinic in Belfast from April 2017 to April 2018 were screened using an in-house MG PCR assay. MG positive samples were subsequently tested using Resistance Plus™ MG assay (Speedx, Australia) to detect 23S rRNA gene mutations associated with macrolide resistance. Results Amongst all study samples, 3.9 % (n=41) tested positive for MG. Out of these 41.5 % (n=17) had a 23S rRNA mutation. The rate of MG was highest in rectal swabs (8.13 %) followed by vaginal swabs (4.96 %) and then male urines (2.85 %). The rate of 23 S rRNA mutations associated with macrolide resistance in positive vaginal swabs was 21.4 % whereas the rate amongst urine and rectal swabs was at least 50 %. Conclusion Data from this study adds to the evidence base to perform MG testing in risk groups in N. Ireland to improve patient outcomes and reduce antimicrobial resistance.

The rates of mutations associated with macrolide resistance in Mycoplasma genitalium among patients with non-gonococcal sexually transmitted infections in Smolensk and Tula

Objective. In this study, we examined the prevalence of macrolide-resistant M. genitalium in two Russian cities, Smolensk and Tula, between 2013 and 2017. Materials and Methods. DNA’s samples were isolated from urethral and cervicovaginal swabs using primary screening and tested for macrolide resistance-associated mutations by real-time PCR. This technology makes it possible to identify any nucleotide substitutions in the 23S rRNA M. genitalium gene at positions 2058, 2059, 2611 M. genitalium by melting curve analysis after the amplification. Results. According to the study in two cities (Smolensk and Tula) macrolide resistance-associated mutations were found in 3, 65% of isolates (21⁄574). The A2058G transition 23S rRNA MGE was the most common mutation that is associated with macrolide resistance: 5⁄12 (41.6%) – Smolensk, 8⁄9 (88.8%) – Tula. Rare substitutions have been reported at position A2058T 23S rRNA MGE and at position C2611T23S rRNA MGE. All received data is published at the AntiMicrobial Resistance Map (AMRmap) (http://AMRmap.com). Conclusions. According to our study, the frequency of macrolide-resistance mutations in M. genitalium was not more than 4% in two cities of Central Russia during 2013–2017. Despite the relatively low rates of resistance of M. genitalium to macrolides in Smolensk and Tula, our data emphasize the need for epidemiological surveillance of resistance in this pathogen.

Macrolide-resistant Mycoplasma genitalium infections in Cuban patients: an underestimated health problem

BackgroundThe increasing prevalence of macrolide resistant Mycoplasma genitalium is a major concern worldwide. In Cuba, several cases of clinical treatment failure with 1 g single dose and extended azithromycin regimen have been detected and the aim of the present investigation was to retrospectively determine the prevalence of macrolide-resistance mediating mutations (MRMM) in M. genitalium-positive samples conserved at the Cuban National Reference Laboratory of Mycoplasma Research between 2009 and 2016.MethodsA total of 280 positive DNA extracts were analysed by a 5’ nuclease assay for detection of M. genitalium MRMM. Ten urogenital specimens from patients with azithromycin treatment failure and MRMM were inoculated in Vero cell to obtain the isolates for subsequent determination of antimicrobial susceptibility.ResultsThe overall prevalence of MRMM was 32%. No MRMM was detected in samples collected between 2009 and 2013 but since 2014 a dramatic increase to 90% (95% CI, 76–96%) in 2016 was seen. Three new M. genitalium isolates were isolated in Vero cell cultures and confirmed phenotypic resistance to macrolides in a cell-culture assisted susceptibility test. Preliminary observations suggest that combination therapy with levofloxacin and doxycycline may represent an affordable option for treatment of macrolide resistant M. genitalium infections.ConclusionsThis investigation showed the rapid emergence and high prevalence of MRMM in M. genitalium-infected patients in Cuba and confirmed the phenotypic resistance in isolates carrying MRMM. We suggest that Cuban guidelines for sexually transmitted infections are modified to include testing for M. genitalium and detection of MRMM in patients with failure of syndromic treatment, to ensure that in these cases, the treatment will be guided by etiologic diagnosis.