Molecular Characterization and Detection of Macrolide and Fluoroquinolone Resistance Determinants in Mycoplasma genitalium in South Africa, 2015 to 2018

Evolving patterns of macrolide and fluoroquinolone resistance in Mycoplasma genitalium: an updated systematic review and meta-analysis

BACKGROUND

Over the past 5 years, since publication of the initial review, studies have provided additional data on macrolide and fluoroquinolone resistance in Mycoplasma genitalium, including data from regions previously lacking this information. We aimed to provide contemporary estimates of macrolide and fluoroquinolone resistance in M genitalium to inform national, regional, and global treatment guidelines.

METHODS

This is an update of a previous systematic review and meta-analysis, which was performed up to Jan 7, 2019. In this update, we searched PubMed, Embase, and MEDLINE from Jan 1, 2018, to April 18, 2023, for published studies reporting macrolide, fluoroquinolone, or dual-class (macrolide and fluoroquinolone) resistance in M genitalium. Data were combined with the previous meta-analysis to examine resistance prevalence in M genitalium samples collected up to and including 2021. Random-effects meta-analyses were used to calculate summary estimates of prevalence. Subgroup analyses by WHO region and four time periods (before 2012 to 2018-21) were performed. This study was registered with PROSPERO, number CRD42021273340.

FINDINGS

166 studies (59 from the previous search period reporting data from M genitalium samples collected between 2003 and 2017, and 107 from the updated search period reporting data from M genitalium samples collected between 2005 and 2021) were included: 157 reporting macrolide resistance (41 countries; 22 974 samples), 89 reporting fluoroquinolone resistance (35 countries; 14 165 samples), and 74 reporting dual-class resistance (34 countries; 11 070 samples). In 2018-21, the overall prevalence of macrolide, fluoroquinolone, and dual-class resistance were 33·3% (95% CI 27·2-39·7), 13·3% (10·0-17·0), and 6·5% (4·0-9·4), respectively. Over time, there was a slight, although not statistically significant, decline in macrolide resistance in the Western Pacific and the Americas, but there was an increase in macrolide resistance in the European region. Fluoroquinolone resistance was highest in the Western Pacific and increased in the European non-Nordic region. ParC S83I was the most common variant associated with fluoroquinolone resistance, increasing from 0% (95% CI <0·0001-0·30) before 2012 to 7·3% (4·7-10·3) in 2018-21; ptrend=0·055.

INTERPRETATION

Macrolide and fluoroquinolone resistance in M genitalium requires ongoing international surveillance, use of resistance assays for optimal antibiotic stewardship, and novel treatment options.

FUNDING

Australian Research Council.

Antibiotic resistance: a global crisis, problems and solutions

Healthy state is priority in today's world which can be achieved using effective medicines. But due to overuse and misuse of antibiotics, a menace of resistance has increased in pathogenic microbes. World Health Organization (WHO) has announced ESKAPE pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter spp.) as the top priority pathogens as these have developed resistance against certain antibiotics. To combat such a global issue, it is utmost important to identify novel therapeutic strategies/agents as an alternate to such antibiotics. To name certain antibiotic adjuvants including: inhibitors of beta-lactamase, efflux pumps and permeabilizers for outer membrane can potentially solve the antibiotic resistance problems. In this regard, inhibitors of lytic domain of lytic transglycosylases provide a novel way to not only act as an alternate to antibiotics but also capable of restoring the efficiency of previously resistant antibiotics. Further, use of bacteriophages is another promising strategy to deal with antibiotic resistant pathogens. Taking in consideration the alternatives of antibiotics, a green synthesis nanoparticle-based therapy exemplifies a good option to combat microbial resistance. As horizontal gene transfer (HGT) in bacteria facilitates the evolution of new resistance strains, therefore identifying the mechanism of resistance and development of inhibitors against it can be a novel approach to combat such problems. In our perspective, host-directed therapy (HDT) represents another promising strategy in combating antimicrobial resistance (AMR). This approach involves targeting specific factors within host cells that pathogens rely on for their survival, either through replication or persistence. As many new drugs are under clinical trials it is advisable that more clinical data and antimicrobial stewardship programs should be conducted to fully assess the clinical efficacy and safety of new therapeutic agents.

Mycoplasma genitalium in the US (MyGeniUS): Surveillance Data From Sexual Health Clinics in 4 US Regions

BACKGROUND

Mycoplasma genitalium (MG) is on the CDC Watch List of Antimicrobial Resistance Threats, yet there is no systematic surveillance to monitor change.

METHODS

We initiated surveillance in sexual health clinics in 6 cities, selecting a quota sample of urogenital specimens tested for gonorrhea and/or chlamydia. We abstracted patient data from medical records and detected MG and macrolide-resistance mutations (MRMs) by nucleic acid amplification testing. We used Poisson regression to estimate adjusted prevalence ratios (aPRs) and 95% CIs, adjusting for sampling criteria (site, birth sex, symptom status).

RESULTS

From October-December 2020 we tested 1743 urogenital specimens: 57.0% from males, 46.1% from non-Hispanic Black persons, and 43.8% from symptomatic patients. MG prevalence was 16.6% (95% CI: 14.9-18.5%; site-specific range: 9.9-23.5%) and higher in St Louis (aPR: 1.9; 1.27-2.85), Greensboro (aPR: 1.8; 1.18-2.79), and Denver (aPR: 1.7; 1.12-2.44) than Seattle. Prevalence was highest in persons <18 years (30.4%) and declined 3% per each additional year of age (aPR: .97; .955-.982). MG was detected in 26.8%, 21.1%, 11.8%, and 15.4% of urethritis, vaginitis, cervicitis, and pelvic inflammatory disease (PID), respectively. It was present in 9% of asymptomatic males and 15.4% of asymptomatic females, and associated with male urethritis (aPR: 1.7; 1.22-2.50) and chlamydia (aPR: 1.7; 1.13-2.53). MRM prevalence was 59.1% (95% CI: 53.1-64.8%; site-specific range: 51.3-70.6%). MRMs were associated with vaginitis (aPR: 1.8; 1.14-2.85), cervicitis (aPR: 3.5; 1.69-7.30), and PID cervicitis (aPR: 1.8; 1.09-3.08).

CONCLUSIONS

MG infection is common in persons at high risk of sexually transmitted infections; testing symptomatic patients would facilitate appropriate therapy. Macrolide resistance is high and azithromycin should not be used without resistance testing.

Effectiveness of sitafloxacin monotherapy for quinolone-resistant rectal and urogenital Mycoplasma genitalium infections: a prospective cohort study

BACKGROUND

Mycoplasma genitalium has a tendency to develop macrolide and quinolone resistance.

OBJECTIVES

We investigated the microbiological cure rate of a 7 day course of sitafloxacin for the treatment of rectal and urogenital infections in MSM.

PATIENTS AND METHODS

This open-label, prospective cohort study was conducted at the National Center for Global Health and Medicine, Tokyo, Japan from January 2019 to August 2022. Patients with M. genitalium urogenital or rectal infections were included. The patients were treated with sitafloxacin 200 mg daily for 7 days. M. genitalium isolates were tested for parC, gyrA and 23S rRNA resistance-associated mutations.

RESULTS

In total, 180 patients (median age, 35 years) were included in this study, of whom 77.0% (97/126) harboured parC mutations, including 71.4% (90/126) with G248T(S83I) in parC, and 22.5% (27/120) harboured gyrA mutations. The median time to test of cure was 21 days. The overall microbiological cure rate was 87.8%. The cure rate was 100% for microbes harbouring parC and gyrA WTs, 92.9% for microbes harbouring parC G248T(S83I) and gyrA WT, and 41.7% for microbes harbouring parC G248T(S83I) and gyrA with mutations. The cure rate did not differ significantly between urogenital and rectal infection (P = 0.359).

CONCLUSIONS

Sitafloxacin monotherapy was highly effective against infection caused by M. genitalium, except strains with combined parC and gyrA mutations. Sitafloxacin monotherapy can be used as a first-line treatment for M. genitalium infections in settings with a high prevalence of parC mutations and a low prevalence of gyrA mutations.

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.

mgpB genotyping and genetic diversity for antimicrobial resistance of Mycoplasma genitalium

Introduction. Antimicrobial resistance (AMR) among Mycoplasma genitalium is a global issue. Understanding the transmission dynamics of infection is an important factor in reducing the occurrence of AMR.

Hypothesis/Gap Statement. There is limited information on the genotyping and AMR traits of M. genitalium .

Aims. Single-locus sequence-based (SLSB) mgpB sequence typing and genetic diversity analyses of AMR M. genitalium isolated from patients in the Republic of Korea were performed to clarify the transmission dynamics and eludicate proper management.

Methodology. Sanger sequencing of mgpB, 23S rRNA, parC and gyrA genes from a total of 103 M . genitalium -positive specimens from 89 patients was carried out.

Results. Twenty-seven different mgpB genotypes (GTs) were identified; 12 had been reported previously and 15 had not. GT7 and GT8 occurred frequently (n=38, 36.89 %, and n=16, 15.53 %, respectively). The genetic diversity of the AMR-determining sites was randomly dispersed among the different GTs. However, these GTs were classified into two phylogenetically distinct clusters that were significantly correlated with patient age and genetic diversity at positions 2058 and 2059 in the 23S rRNA gene. The GTs of 20 consecutive samples from 6 patients were compared to investigate temporal changes in GTs. One specimen changed its GT during follow-up, suggesting a new infection.

Conclusions. mgpB sequence typing can be a reliable tool for epidemiological studies. Two clusters have different characteristics in terms of genetic diversity. The cluster with genetic diversity in the AMR-determining site may be explained by the high prevalence of the specimens and subsequent antimicrobial exposure during the study period.

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

OBJECTIVE

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.

METHODS

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 Allplex^TM 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 Allplex^TM MG & AziR assay (Seegene) for the detection of M. genitalium was also performed in a subset of 121 samples.

RESULTS

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 Allplex^TM assay indicating a good correlation between the TaqMan Assay and the Allplex^TM. 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.

CONCLUSION

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.