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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., Competing Interests: LZ and STS are inventors on the patent: Detection and antibiotic resistance profiling of microorganisms, WO/2020/178575. This does not alter our adherence to PLOS ONE policies on sharing data and materials.

Objectives: Azithromycin 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 coinfections of CT with MG carrying MRAM, and risk factors for MG-MRAM among a sexual health clinic population., Study Design and Setting: Among symptomatic and STI-contact clinic attendees in London, prevalence of CT-MG coinfection and MG-MRAM were estimated using nucleic acid amplification testing and Sanger sequencing, respectively, and their associated risk factors analysed using logistic regression., Results: MG prevalence was 7.5% (23/307), 17.3% (30/173), and 11.4% (8/70) in females, men who have sex with women (MSW) and men who have sex with men (MSM), respectively; MG coinfection in CT-infected participants represented 28.0% (7/25), 13.5% (5/37), 0.0% (0/0), respectively. Presence of MG-MRAM was 39.1% (9/23) in female swabs, 70.0% (21/30) in MSW urine and 83.3% (5/6) in MSM rectal swabs. In multivariate analyses, coinfection with another STI was strongly associated with MG-MRAM (OR: 7.19; 95% CI: 2.4 to 21.5)., Conclusion: A significant proportion of participants in our study of symptomatic patients and STI contacts were infected with macrolide-resistant MG, suggesting that testing for MG and MRAM, for MG positives, might be clinically useful. The findings also suggest services explore potential benefits of testing CT positive samples for MG in these patient groups. Where MG testing is not available, potential high rates of MG coinfection should be borne in mind when considering azithromycin in the treatment of CT among STI contacts and symptomatic patients., (© Author(s) (or their employer(s)) 2021. No commercial re-use. See rights and permissions. Published by BMJ.)

BackgroundWidespread ceftriaxone antimicrobial resistance (AMR) threatens Neisseria gonorrhoeae (NG) treatment, with few alternatives available. AMR point-of-care tests (AMR POCT) may enable alternative treatments, including abandoned regimens, sparing ceftriaxone use. We assessed cost-effectiveness of five hypothetical AMR POCT strategies: A-C included a second antibiotic alongside ceftriaxone; and D and E consisted of a single antibiotic alternative, compared with standard care (SC: ceftriaxone and azithromycin).AimAssess costs and effectiveness of AMR POCT strategies that optimise NG treatment and reduce ceftriaxone use.MethodsThe five AMR POCT treatment strategies were compared using a decision tree model simulating 38,870 NG-diagnosed England sexual health clinic (SHC) attendees; A micro-costing approach, representing cost to the SHC (for 2015/16), was employed. Primary outcomes were: total costs; percentage of patients given optimal treatment (regimens curing NG, without AMR); percentage of patients given non-ceftriaxone optimal treatment; cost-effectiveness (cost per optimal treatment gained).ResultsAll strategies cost more than SC. Strategy B (azithromycin and ciprofloxacin (azithromycin preferred); dual therapy) avoided most suboptimal treatments (n = 48) but cost most to implement (GBP 4,093,844 (EUR 5,474,656)). Strategy D (azithromycin AMR POCT; monotherapy) was most cost-effective for both cost per optimal treatments gained (GBP 414.67 (EUR 554.53)) and per ceftriaxone-sparing treatment (GBP 11.29 (EUR 15.09)) but with treatment failures (n = 34) and suboptimal treatments (n = 706).ConclusionsAMR POCT may enable improved antibiotic stewardship, but require net health system investment. A small reduction in test cost would enable monotherapy AMR POCT strategies to be cost-saving.

Background: Mass drug administration (MDA) of 20 mg/kg (maximum 1 g in adults) azithromycin for ocular Chlamydia trachomatis (CT) infection is a key component of the WHO trachoma elimination strategy. However, this dose may be suboptimal in Mycoplasma genitalium infection and may encourage emergence of antimicrobial resistance (AMR) to azithromycin., Objectives: To determine the effect of MDA for trachoma elimination on M. genitalium prevalence, strain type and azithromycin resistance., Methods: A secondary analysis of CT-negative vulvovaginal swabs from three outpatient antenatal clinics (Honiara, Solomon Islands) from patients recruited either pre-MDA, or 10 months post-MDA in two cross-sectional surveys was carried out. Swabs were tested for M. genitalium infection using Fast Track Diagnostics Urethritis Plus nucleic acid amplification assay. M. genitalium -positive samples were subsequently tested for azithromycin resistance by sequencing domain V of the 23S rRNA DNA region of M. genitalium and underwent phylogenetic analysis by dual locus sequence typing., Results: M. genitalium prevalence was 11.9% (28/236) in women pre-MDA and 10.9% (28/256) 10 months post-MDA (p=0.7467). Self-reported receipt of azithromycin as part of MDA was 49.2% in women recruited post-MDA and 17.9% (5/28) in those who tested M. genitalium positive. Of samples sequenced (21/28 pre-MDA, 22/28 post-MDA), all showed a macrolide susceptible genotype. Strain typing showed that sequence types diverged into two lineages, with a suggestion of strain replacement post-MDA., Conclusion: A single round of azithromycin MDA in an island population with high baseline M. genitalium prevalence did not appear to impact on either prevalence or azithromycin resistance, in contrast to reported decreased genital CT prevalence in the same population. This may be due to limitations such as sample size, including CT-negative samples only, and low MDA coverage. Further investigation of the impact of multiple rounds of MDA on M. genitalium azithromycin AMR in antibiotic experienced and naïve populations is warranted., Competing Interests: Competing interests: MAH, EMHE and STS disclose having received funding outside the submitted work from Atlas Genetics, Alere, Cepheid, SpeeDx, Mologic and Sekisui. MJP discloses having received funding outside the submitted work from Atlas Genetics, Alere, Cepheid and Sekisui. AVN discloses having received funding outside the submitted work from Alere, Cepheid, SpeeDx and Sekisui. EMHE discloses their membership of the Becton Dickinson 'Provision of Sexual Health in the UK' advisory board. All other authors have nothing to disclose., (© Author(s) (or their employer(s)) 2019. Re-use permitted under CC BY. Published by BMJ.)

Background High rates of antimicrobial resistance (AMR) in Neisseria gonorrhoeae hinder effective treatment, but molecular AMR diagnostics may help address the challenge. This study aimed to appraise the literature for resistance-associated genotypic markers linked to fluoroquinolones and macrolides, to identify and review their use in diagnostics., Methods: Medline and EMBASE databases were searched and data pooled to evaluate associations between genotype and phenotypic resistance. The minimum inhibitory concentration (MIC) cut-offs were ≤ 0.06 mg L-1 for non-resistance to ciprofloxacin and ≤ 0.5 mg L-1 for non-resistance to azithromycin., Results: Diagnostic accuracy estimates were limited by data availability and reporting. It was found that: 1) S91 and D95 mutations in the GyrA protein independently predicted ciprofloxacin resistance and, used together, gave 98.6% (95% confidence interval (CI) 98.0-99.0%) sensitivity and 91.4% (95%CI 88.6-93.7%) specificity; 2) the number of 23S rRNA gene alleles with C2611T or A2059G mutations was highly correlated with azithromycin resistance, with mutation in any allele giving a sensitivity and specificity of 66.1% (95%CI 62.1-70.0%) and 98.9% (95%CI 97.5-99.5%) respectively. Estimated negative (NPV) and positive predictive values (PPV) for a 23S rRNA diagnostic were 98.6% (95%CI 96.8-99.4%) and 71.5% (95%CI 68.0-74.8%) respectively; 3) mutation at amino acid position G45 in the MtrR protein independently predicted azithromycin resistance; however, when combined with 23S rRNA, did not improve the PPV or NPV., Conclusions: Viable candidates for markers of resistance detection for incorporation into diagnostics were demonstrated. Such tests may enhance antibiotic stewardship and treatment options.

Sexually transmitted infections (STIs) continue to be a major public health concern in the United Kingdom (UK). Epidemiological models have shown that narrowing the time between STI diagnosis and treatment may reduce the population burden of infection, and rapid, accurate point-of-care tests (POCTs) have potential for increasing correct treatment and mitigating the spread of antimicrobial resistance (AMR). We developed the Precise social science programme to incorporate clinician and patient opinions on potential designs and implementation of new POCTs for multiple STIs and AMR detection. We conducted qualitative research, consisting of informal interviews with clinicians and semi-structured in-depth interviews with patients, in six sexual health clinics in the UK. Interviews with clinicians focused on how the new POCTs would likely be implemented into clinical care; these new clinical pathways were then posed to patients in in-depth interviews. Patient interviews showed acceptability of POCTs, however, willingness to wait in clinic for test results depended on the context of patients' sexual healthcare seeking. Patients reporting frequent healthcare visits often based their expectations and opinions of services and POCTs on previous visits. Patients' suggestions for implementation of POCTs included provision of information on service changes and targeting tests to patients concerned they are infected. Our data suggests that patients may accept new POCT pathways if they are given information on these changes prior to attending services and to consider implementing POCTs among patients who are anxious about their infection status and/or who are experiencing symptoms., Competing Interests: ADREU has received funding from Binx Health (formerly Atlas Genetics Ltd), Alere, Cepheid, SpeedDx, Mologic, Revolugen and Sekisui. SSF and EHE have been members of the BD Diagnostics Advisory Panel on UK Provision of Sexual Health Services. This does not alter our adherence to PLOS ONE policies on sharing data and materials.

In addition to inadequate access to early diagnosis and treatment with antimicrobial agents for patients and sexual contacts, management and control of STIs is significantly challenged by emergence and spread of antimicrobial resistance (AMR), particularly for STIs such as Neisseria gonorrhoeae and Mycoplasma genitalium This is further compounded by use of nucleic acid amplification techniques for diagnosis, resulting in reduced phenotypic AMR testing for N. gonorrhoeae and absence or suboptimal AMR surveillance for guiding treatment of both STIs in many settings. Rapid accurate point-of-care (POC) tests for diagnosis of all STIs would be valuable but to significantly impact treatment precision and management of N. gonorrhoeae and M. genitalium infections, combinations of rapid POC diagnostic and AMR testing (POC-AMR) will likely be required. This strategy would combat STI burden and AMR emergence and spread by enabling diagnosis and individualised treatment at the first healthcare visit, potentially reducing selection pressure on recommended antimicrobials, reducing transmission of resistant strains and providing means for AMR surveillance. Microfluidic and nanotechnology platforms under development for rapid detection of STIs provide a basis to also develop molecular rapid POC-AMR prediction. A number of prototypic devices are in the pipeline but none as yet approved for routine use. However, particularly for N. gonorrhoeae , more knowledge is required to assess which antimicrobials lend themselves to a genotypic POC-AMR approach, in relation to genotypic-phenotypic associations and potential impact clinically and epidemiologically. Key for successful deployment will include also understanding cost-effectiveness, cost-consequences and acceptability for key stakeholders., Competing Interests: Competing interests: STS is grant holder for the National Institute for Health Research (NIHR) i4i Programme (grant number II-LB-0214-20005). The views expressed are those of the authors and not necessarily those of the NIHR, the NHS or the UK Department of Health. STS has also received funding from Atlas Genetics to conduct performance evaluations of its io POC system. None for MU and FM., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.)

Background:  Empirical antibiotic therapy for nongonococcal urethritis (NGU) and cervicitis is aimed at Chlamydia trachomatis, but Mycoplasma genitalium, which also commonly causes undiagnosed NGU, necessitates treatment with macrolides or fluoroquinolones rather than doxycycline, the preferred chlamydia treatment. Prevalence of M. genitalium and associated genotypic markers of macrolide and fluoroquinolone resistance among men symptomatic of urethritis were investigated. Genetic diversity of M. genitalium populations was determined to infer whether findings were applicable beyond our setting., Methods:  Mycoplasma genitalium and other NGU pathogens were detected using nucleic acid amplification methods, and DNA sequencing was used to detect genotypic resistance markers of macrolide and fluoroquinolone antibiotics in 23S ribosomal RNA, gyrA, gyrB, and parC genes. MG191 single-nucleotide polymorphism typing and MG309 variable number tandem analysis were combined to assign a dual locus sequence type (DLST) to each positive sample., Results:  Among 217 men, M. genitalium prevalence was 16.7% (95% confidence interval [CI], 9.5%-24.0%) and C. trachomatis prevalence was 14.7% (95% CI, 7.8%-21.6%) in NGU cases. Nine of 22 (41%; 95% CI, 20%-62%) patients with M. genitalium were infected with DLSTs possessing genotypic macrolide resistance and 1 patient was infected with a DLST having genotypic fluoroquinolone resistance. Typing assigned M. genitalium DLSTs to 2 major clusters, broadly distributed among previously typed international strains. Genotypic macrolide resistance was spread within these 2 clusters., Conclusions:  Mycoplasma genitalium is a frequent undiagnosed cause of NGU in this population with rates of macrolide resistance higher than those previously documented. Current guidelines for routine testing and empirical treatment of NGU should be modified to reduce treatment failure of NGU and the development of further resistance.