Background review for the '2020 European guideline for the diagnosis and treatment of gonorrhoea in adults'

Anorectal Neisseria gonorrhoeae infections in women with and without reported anal sex and sex workers in sexual health centres in the Netherlands: a retrospective cohort study

BACKGROUND

Control of Neisseria gonorrhoeae infection (gonorrhoea) depends on effective testing strategies. Anorectal testing in women is often done on indication of anal sex; however, anorectal infections are seen with and without anal exposure, possibly caused by autoinoculation. This study aims to enhance understanding of anorectal infections in women, by identifying risk factors for anorectal diagnosis.

METHODS

In this retrospective cohort study we used national surveillance data from Dutch sexual health centres from Jan 1, 2016, to Dec 31, 2021. We included cisgender women having sex with men who were tested urogenitally and anorectally for gonorrhoea. Due to different testing policies, we identified three groups: women who had not reported recent anal sex (in the past 6 months), women who had reported recent anal sex, and sex workers. Extracted data for analyses included demographics, sexual behaviour, and diagnosis of a sexually transmitted infection (STI). Per group, multivariable models using Firth's penalised maximum likelihood logistic regression were constructed, identifying determinants of anorectal gonorrhoea among all women and among gonorrhoea-positive women only. Variables included in model construction were age, education level, migration background, number of partners, condom use, partner notification, STI symptoms, having a partner who has sex with men (MSM) or a migrant partner, previous STI test, anal sex, and chlamydia and gonorrhoea diagnoses per anatomical location.

FINDINGS

In total, 117 693 women were included: 43 757 women without reported recent anal sex, 51 728 women with reported recent anal sex, and 22 208 sex workers. In all three groups, around 2% of women were gonorrhoea positive, and 70% or more of women had an anorectal infection. The strongest determinant of anorectal gonorrhoea was a concurrent urogenital gonorrhoea diagnosis (adjusted odds ratios [aOR] 782 [95% CI 605-1018]) among women without reported recent anal sex (612 [490-768] among women with reported recent anal sex, and 464 [335-652] among sex workers). Among gonorrhoea-positive women, determinants of anorectal gonorrhoea were urogenital and anorectal chlamydia co-infection (aOR 2·03 [95% CI 1·38-3·02], for women without reported anal sex) and migration background (1·44 [1·02-2·06], for women with reported anal sex). Determinants among sex workers were condomless sex (2·43 [1·55-3·82]), anal sex (1·71 [1·10-2·66]), MSM or migrant partner (1·78 [1·13-2·79]), and urogenital and anorectal chlamydia co-infection (2·28 [1·11-5·14]).

INTERPRETATION

These findings support the possibility of an autoinoculation process from the urogenital to the anorectal location due to the very strong correlation between urogenital and anorectal gonorrhoea, and due to the similarity of results across all three groups. Current testing strategies could miss anorectal infections, which should be considered when developing gonorrhoea prevention and control guidelines.

FUNDING

None.

Bacitracin enhances ceftriaxone susceptibility of the high-level ceftriaxone-resistant gonococcal FC428 clone

IMPORTANCE

Ceftriaxone-based antimicrobial therapies for gonorrhea are threatened by waning ceftriaxone susceptibility levels and the global dissemination of the high-level ceftriaxone-resistant gonococcal FC428 clone. Combination therapy can be an effective strategy to restrain the development of ceftriaxone resistance, and for that purpose, it is important to find an alternative antimicrobial to replace azithromycin, which has recently been removed in some countries from the recommended ceftriaxone plus azithromycin dual-antimicrobial therapy. Ideally, the second antimicrobial should display synergistic activity with ceftriaxone. We hypothesized that bacitracin might display synergistic activity with ceftriaxone because of their distinct mechanisms targeting bacterial cell wall synthesis. In this study, we showed that bacitracin indeed displays synergistic activity with ceftriaxone against Neisseria gonorrhoeae. Importantly, strains associated with the FC428 clone appeared to be particularly susceptible to the bacitracin plus ceftriaxone combination, which might therefore be an interesting dual therapy for further in vivo testing.

Interruption time series analysis using autoregressive integrated moving average model: evaluating the impact of COVID-19 on the epidemic trend of gonorrhea in China

BACKGROUND

Interrupted time series (ITS) analysis is a growing method for assessing intervention impacts on diseases. However, it remains unstudied how the COVID-19 outbreak impacts gonorrhea. This study aimed to evaluate the effect of COVID-19 on gonorrhea and predict gonorrhea epidemics using the ITS-autoregressive integrated moving average (ARIMA) model.

METHODS

The number of gonorrhea cases reported in China from January 2005 to September 2022 was collected. Statistical descriptions were applied to indicate the overall epidemiological characteristics of the data, and then the ITS-ARIMA was established. Additionally, we compared the forecasting abilities of ITS-ARIMA with Bayesian structural time series (BSTS), and discussed the model selection process, transfer function, check model fitting, and interpretation of results.

RESULT

During 2005-2022, the total cases of gonorrhea were 2,165,048, with an annual average incidence rate of 8.99 per 100,000 people. The highest incidence rate was 14.2 per 100,000 people in 2005 and the lowest was 6.9 per 100,000 people in 2012. The optimal model was ARIMA (0,1, (1,3)) (0,1,1)12 (Akaike's information criterion = 3293.93). When predicting the gonorrhea incidence, the mean absolute percentage error under the ARIMA (16.45%) was smaller than that under the BSTS (22.48%). The study found a 62.4% reduction in gonorrhea during the first-level response, a 46.47% reduction during the second-level response, and an increase of 3.6% during the third-level response. The final model estimated a step change of - 2171 (95% confidence interval [CI] - 3698 to - 644) cases and an impulse change of - 1359 (95% CI - 2381 to - 338) cases. Using the ITS-ARIMA to evaluate the effect of COVID-19 on gonorrhea, the gonorrhea incidence showed a temporary decline before rebounding to pre-COVID-19 levels in China.

CONCLUSION

ITS analysis is a valuable tool for gauging intervention effectiveness, providing flexibility in modelling various impacts. The ITS-ARIMA model can adeptly explain potential trends, autocorrelation, and seasonality. Gonorrhea, marked by periodicity and seasonality, exhibited a downward trend under the influence of COVID-19 intervention. The ITS-ARIMA outperformed the BSTS, offering superior predictive capabilities for the gonorrhea incidence trend in China.

The Molecular Genetic Epidemiology and Antimicrobial Resistance of Neisseria gonorrhoeae Strains Obtained from Clinical Isolates in Central Panama

We aim to analyze Neisseria gonorrhoeae isolates in central Panama, characterize the associated gonococcal antimicrobial resistance (AMR) and conduct molecular epidemiology and genetic typing. We conducted a retrospective study based on N. gonorrhoeae hospital isolates collected between 2013 and 2018. AMR was determined using dilution agar and Etest®. Molecular typing was conducted using the Multilocus Sequence Typing (ST) scheme. The isolates analyzed (n = 30) showed resistance to penicillin (38%), tetracycline (40%), and ciprofloxacin (30%), and sensitivity to extended-spectrum cephalosporins and azithromycin. We identified 11 STs, the most frequent of which was ST1901 among the strains with decreased sensitivity and resistance to three types of antibiotics. We identified eight variations for the penA gene, all non-mosaic, with type II LVG as the most frequent (50%). To the best of our knowledge, we conducted the first Central American genomic study that analyzes a collection of gonococcal isolates, which represents a benchmark for future epidemiological and molecular genetic studies. The high prevalence of ciprofloxacin, tetracycline, and penicillin resistance, in addition to the identification of the worldwide spread of multidrug-resistant clone ST1901, should prompt the continuous and reinforced surveillance of AMR, including the molecular epidemiology of N. gonorrhoeae in Panama.

HIV and syphilis testing for women and heterosexual men aged above 25 years in the Netherlands: possibilities for targeted testing at sexual health centres

OBJECTIVES

Targeted testing policy for HIV/syphilis at Dutch sexual health centres (SHCs) was evaluated for its efficiency in younger heterosexuals but not for heterosexuals ≥25 years. Currently, all older heterosexuals are tested for HIV/syphilis at SHCs. To explore possibilities for increased efficiency of testing in heterosexuals aged >25 years, this study aimed to identify determinants of HIV and syphilis diagnoses that could be used in targeted testing strategies.

DESIGN

An observational study using surveillance data from all Dutch SHC.

PARTICIPANTS

Women and heterosexual men aged >25 years visiting SHC between 2015 and 2021.

PRIMARY AND SECONDARY OUTCOME MEASURES

The primary outcome was HIV/syphilis diagnosis, determinants of a diagnosis were analysed. Based on these determinants and their applicability in SHC practice, different targeted testing scenarios were evaluated. For each scenario, the percentage of consultations involving HIV and syphilis testing and the total amount of missed HIV and syphilis diagnoses were calculated.

RESULTS

109 122 consultations were included among 75 718 individuals. The strongest determinants of HIV/syphilis diagnosis were HIV/syphilis-specific symptoms (adjusted OR (aOR) 34.9 (24.1-50.2)) and receiving partner notification (aOR 18.3 (13.2-25.2)), followed by low/middle education level (aOR 2.8 (2.0-4.0)), male sex (aOR 2.2 (1.6-3.0)) and age ≥30 years (aOR 1.8 (1.3-2.5)). When applying feasible determinants to targeted testing scenarios, HIV/syphilis testing would have been conducted in 54.5% of all consultations, missing 2 HIV and 3 syphilis diagnoses annually (13.4% and 11.4% of all diagnoses, respectively). In the scenario with the lowest number of missed HIV/syphilis diagnoses (0.3 HIV and 2 syphilis diagnoses annually), HIV/syphilis testing would have been conducted in 74.2% of all consultations.

CONCLUSIONS

In any targeted testing scenario studied, HIV and/or syphilis diagnoses would have been missed. This raises the question whether it is acceptable to put any of these scenarios into practice. This study contributes to a discussion about the impact of targeted testing policy.

Emergence of Azithromycin-Resistant Neisseria gonorrhoeae Isolates Belonging to the NG-MAST Genogroup 12302 in Russia

The goal of this work was to determine the factors affecting the emergence of azithromycin-resistant Neisseria gonorrhoeae isolates in Russia, where azithromycin was never recommended for the treatment of gonococcal infections. Clinical N. gonorrhoeae isolates collected in 2018-2021 (428 isolates) were analyzed. No azithromycin-resistant isolates were found in 2018-2019, but in 2020-2021, a significant increase in the ratio of azithromycin-resistant isolates was observed: 16.8% and 9.3%, respectively. A hydrogel DNA microarray was developed for the analysis of resistance determinants: mutations in the genes encoding the mtrCDE efflux system and in all four copies of the 23S rRNA gene (position 2611). A majority of the azithromycin-resistant Russian isolates belonged to the NG-MAST G12302 genogroup, and the resistance was associated with the presence of a mosaic structure of the mtrR gene promoter region with the -35 delA deletion, an Ala86Thr mutation in the mtrR gene, and a mosaic structure of the mtrD gene. A comparative phylogenetic study of modern Russian and European N. gonorrhoeae populations allowed us to conclude that the emergence of azithromycin resistance in Russia in 2020 was the result of the appearance and spread of European N. gonorrhoeae strains belonging to the G12302 genogroup due to possible cross-border transfer.

Chlamydia Trachomatis/Neisseria Gonorrhea Retesting Among Adolescents and Young Adults in a Primary Care Network

PURPOSE

Chlamydia trachomatis/Neisseria gonorrhea (CT/NG) retesting three months after diagnosis is a guideline-recommended strategy to detect re-infections. Adolescents and young adults are priority populations in the U.S. Sexually Transmitted Infections National Strategic Plan, but there is a lack of research examining CT/NG retesting among these populations. This study describes retesting following CT/NG diagnosis among adolescent and young adult patients at Title X and non-Title X clinics and measures the association of patient-level factors with CT/NG retesting.

METHODS

We evaluated electronic medical records from 2014 to 2020 from an academic urban-suburban primary care network. The primary outcome was retesting, defined as a diagnostic test for CT or NG ordered 8-16 weeks after index diagnosis. Mixed effects logistic regression modeling stratified by Title X funding was conducted to evaluate the association of patient-level factors with CT/NT retesting.

RESULTS

Overall, 23.5% (n = 731) of patients were retested within 8-16 weeks following index CT/NG diagnosis. A significantly greater proportion of Title X patients were retested compared to non-Title X patients. Males were significantly less likely to be retested compared to females, and the proportion of patients retested decreased significantly over the study period.

DISCUSSION

Guideline-recommended retesting following CT/NG diagnosis was low in this young primary care cohort, especially among male and non-Title X clinic patients. Decreases in CT/NG retesting over the study period may be contributing to worsening of the STI epidemic. Our results provide insights into CT/NG retesting that can inform efforts to end the STI epidemic.

Current Susceptibility Surveillance and Distribution of Antimicrobial Resistance in N. gonorrheae within WHO Regions

Neisseria gonorrhoeae (N. gonorrhoeae) is the etiological agent of the second most common sexually transmitted disease in the world, gonorrhoea. Currently recommended and last available first-line therapy is extended-spectrum cephalosporins most often combined with azitromycin. However, misuse of antibiotics and the abilities of N. gonorrhoeae to acquire new genetic and plasmid-borne resistance determinants has gradually led to the situation where this bacterium has become resistant to all major classes of antibiotics. Together with a generally slow update of treatment guidelines globally, as well as with the high capacity of gonococci to develop and retain AMR, this may lead to the global worsening of gonococcal AMR. Since effective vaccines are unavailable, the management of gonorrhoea relies mostly on prevention and accurate diagnosis, together with antimicrobial treatment. The study overviews the latest results of mostly WHO-initiated studies, primarily focusing on the data regarding the molecular basis of the resistance to the current and novel most promising antibacterial agents, which could serve to establish or reinforce the continual, quality-assured and comparable AMR surveillance, including systematic monitoring and treatment with the use of molecular AMR prediction methods.

Molecular Mechanisms of Drug Resistance and Epidemiology of Multidrug-Resistant Variants of Neisseria gonorrhoeae

The paper presents various issues related to the increasing drug resistance of Neisseria gonorrhoeae and the occurrence and spread of multidrug-resistant clones. One of the most important is the incidence and evolution of resistance mechanisms of N. gonorrhoeae to beta-lactam antibiotics. Chromosomal resistance to penicillins and oxyimino-cephalosporins and plasmid resistance to penicillins are discussed. Chromosomal resistance is associated with the presence of mutations in the PBP2 protein, containing mosaic variants and nonmosaic amino acid substitutions in the transpeptidase domain, and their correlation with mutations in the mtrR gene and its promoter regions (the MtrCDE membrane pump repressor) and in several other genes, which together determine reduced sensitivity or resistance to ceftriaxone and cefixime. Plasmid resistance to penicillins results from the production of beta-lactamases. There are different types of beta-lactamases as well as penicillinase plasmids. In addition to resistance to beta-lactam antibiotics, the paper covers the mechanisms and occurrence of resistance to macrolides (azithromycin), fluoroquinolones and some other antibiotics. Moreover, the most important epidemiological types of multidrug-resistant N. gonorrhoeae, prevalent in specific years and regions, are discussed. Epidemiological types are defined as sequence types, clonal complexes and genogroups obtained by various typing systems such as NG-STAR, NG-MAST and MLST. New perspectives on the treatment of N. gonorrhoeae infections are also presented, including new drugs active against multidrug-resistant strains.

Antibiotic Resistance in Neisseria gonorrhoeae: Challenges in Research and Treatment

Gonococcal infection caused by the Gram-negative bacteria Neisseria gonorrhoeae is one of the most common sexually transmitted infections (STIs) worldwide [...]

Trends and regional variations of gonococcal antimicrobial resistance in the Netherlands, 2013 to 2019

Background

Gonococcal antimicrobial resistance is emerging worldwide and is monitored in the Netherlands in 18 of 24 Sexual Health Centres (SHC).

Aim

To report trends, predictors and regional variation of gonococcal azithromycin resistance (AZI-R, minimum inhibitory concentration (MIC) > 1 mg/L) and ceftriaxone decreased susceptibility (CEF-DS, MIC > 0.032 mg/L) in 2013–2019.

Methods

SHC reported data on individual characteristics, sexually transmitted infection diagnoses, and susceptibility testing (MIC, measured by Etest). We used multilevel logistic regression analysis to identify AZI-R/CEF-DS predictors, correcting for SHC region. Population differences’ effect on regional variance of AZI-R and CEF-DS was assessed with a separate multilevel model.

Results

The study included 13,172 isolates, predominantly (n = 9,751; 74%) from men who have sex with men (MSM). Between 2013 and 2019, annual proportions of AZI-R isolates appeared to increase from 2.8% (37/1,304) to 9.3% (210/2,264), while those of CEF-DS seemed to decrease from 7.0% (91/1,306) to 2.9% (65/2,276). Among SHC regions, 0.0‒16.9% isolates were AZI-R and 0.0−7.0% CEF-DS; population characteristics could not explain regional variance. Pharyngeal strain origin and consultation year were significantly associated with AZI-R and CEF-DS for MSM, women, and heterosexual men. Among women and heterosexual men ≥ 4 partners was associated with CEF-DS, and ≥ 10 with AZI-R.

Conclusions

No resistance or decreasing susceptibility was found for CEF, the first line gonorrhoea treatment in the Netherlands. Similar to trends worldwide, AZI-R appeared to increase. Regional differences between SHC support nationwide surveillance with regional-level reporting. The increased risk of resistance/decreased susceptibility in pharyngeal strains underlines the importance of including extragenital infections in gonococcal resistance surveillance.

Significant increase in azithromycin "resistance" and susceptibility to ceftriaxone and cefixime in Neisseria gonorrhoeae isolates in 26 European countries, 2019

Background

The European Gonococcal Antimicrobial Surveillance Programme (Euro-GASP) performs annual sentinel surveillance of Neisseria gonorrhoeae susceptibility to therapeutically relevant antimicrobials across the European Union/European Economic Area (EU/EEA). We present the Euro-GASP results from 2019 (26 countries), linked to patient epidemiological data, and compared with data from previous years.

Methods

Agar dilution and minimum inhibitory concentration (MIC) gradient strip methodologies were used to determine the antimicrobial susceptibility (using EUCAST clinical breakpoints, where available) of 3239 N. gonorrhoeae isolates from 26 countries across the EU/EEA. Significance of differences compared with Euro-GASP results in previous years was analysed using Z-test and the Pearson's χ2 test was used to assess significance of odds ratios for associations between patient epidemiological data and antimicrobial resistance.

Results

European N. gonorrhoeae isolates collected between 2016 and 2019 displayed shifting MIC distributions for; ceftriaxone, with highly susceptible isolates increasing over time and occasional resistant isolates each year; cefixime, with highly-susceptible isolates becoming increasingly common; azithromycin, with a shift away from lower MICs towards higher MICs above the EUCAST epidemiological cut-off (ECOFF); and ciprofloxacin which is displaying a similar shift in MICs as observed for azithromycin. In 2019, two isolates displayed ceftriaxone resistance, but both isolates had MICs below the azithromycin ECOFF. Cefixime resistance (0.8%) was associated with patient sex, with resistance higher in females compared with male heterosexuals and men-who-have-sex-with-men (MSM). The number of countries reporting isolates with azithromycin MICs above the ECOFF increased from 76.9% (20/26) in 2016 to 92.3% (24/26) in 2019. Isolates with azithromycin MICs above the ECOFF (9.0%) were associated with pharyngeal infection sites. Following multivariable analysis, ciprofloxacin resistance remained associated with isolates from MSM and heterosexual males compared with females, the absence of a concurrent chlamydial infection, pharyngeal infection sites and patients ≥ 25 years of age.

Conclusions

Resistance to ceftriaxone and cefixime remained uncommon in EU/EEA countries in 2019 with a significant decrease in cefixime resistance observed between 2016 and 2019. The significant increase in azithromycin “resistance” (azithromycin MICs above the ECOFF) threatens the effectiveness of the dual therapy (ceftriaxone + azithromycin), i.e., for ceftriaxone-resistant cases, currently recommended in many countries internationally and requires close monitoring.

Molecular Epidemiology, Antimicrobial Surveillance, and PK/PD Analysis to Guide the Treatment of Neisseria gonorrhoeae Infections

The aim of this study was to apply molecular epidemiology, antimicrobial surveillance, and PK/PD analysis to guide the antimicrobial treatment of gonococci infections in a region of the north of Spain. Antibiotic susceptibility testing was performed on all isolates (2017 to 2019, n = 202). A subset of 35 isolates intermediate or resistant to at least two antimicrobials were selected to search for resistance genes and genotyping through WGS. By Monte Carlo simulation, we estimated the probability of target attainment (PTA) and the cumulative fraction of response (CFR) of the antimicrobials used to treat gonorrhea, both indicative of the probability of treatment success. In total, 2.0%, 6.4%, 5.4%, and 48.2% of the isolates were resistant to ceftriaxone, cefixime, azithromycin, and ciprofloxacin, respectively. Twenty sequence types were identified. Detected mutations were related to antibiotic resistance. PK/PD analysis showed high probability of treatment success of the cephalosporins. In conclusion, multiple populations of N. gonorrhoeae were identified. We can confirm that ceftriaxone (even at the lowest dose: 250 mg) and oral cefixime are good candidates to treat gonorrhea. For patients allergic to cephalosporins, ciprofloxacin should be only used if the MIC is known and ≤0.125 mg/L; this antimicrobial is not recommended for empirical treatment.

Clinical performance of four multiplex real-time PCR kits detecting urogenital and sexually transmitted pathogens

OBJECTIVES

We evaluated the clinical performances of four multiplex real-time PCR commercial kits for the detection of Chlamydia trachomatis, Neisseria gonorrhoeae, Mycoplasma genitalium and Trichomonas vaginalis: the STI PLUS ELITe MGB kit (ELITechGroup), N. gonorrhoeae/C. trachomatis/M. genitalium/T.vaginalis Real-TM kit (Sacace Biotechnologies), Allplex STI Essential kit (Seegene), and FTD Urethritis Plus kit (Fast-Track Diagnostics).

METHODS

The kit performance for C. trachomatis, N. gonorrhoeae, M. genitalium and T. vaginalis detection was compared to that of the cobas CT/NG and TV/MG kits (Roche Diagnostics) using 425 samples, mainly urine and cervicovaginal, throat and rectal swabs. Detection of Ureaplasma parvum, U. urealyticum and Mycoplasma hominis were compared to that of in-house TaqMan PCRs.

RESULTS

The four kits showed good performances for the detection of C. trachomatis. They all presented a low positive agreement for the detection of M. genitalium and T. vaginalis (ranges 63.3-74.1% and 51.2-68.4%, respectively) compared to the cobas MG/TV kit. The Seegene and Sacace kits showed additional low positive agreement for the detection of N. gonorrhoeae (71.2%, 95%CI 61.8-79.0 and 63.1%, 95%CI 53.5-71.8, respectively). We observed a slight but significant lower negative agreement for N. gonorrhoeae detection using the ELITechGroup kit (92.5%, 89.1-94.9) and for M. genitalium detection using the Fast-Track kit (93.2%, 89.6-95.7) compared to other kits.

CONCLUSION

Multiplex real-time PCR kits are convenient methods for the detection of several pathogens associated with sexually transmitted infections (STIs) in a single step, but colonizing Ureaplasma spp. and M. hominis species should not be included in these kits. Users should be aware of the weak performance of some kits for the detection of M. genitalium and T. vaginalis.

Choosing New Therapies for Gonorrhoea: We Need to Consider the Impact on the Pan-Neisseria Genome. A Viewpoint

The development of new gonorrhoea treatment guidelines typically considers the resistance-inducing effect of the treatment only on Neisseria gonorrhoeae. Antimicrobial resistance in N. gonorrhoeae has, however, frequently first emerged in commensal Neisseria species and then been passed on to N. gonorrhoeae via transformation. This creates the rationale for considering the effect of gonococcal therapies on resistance in commensal Neisseria. We illustrate the benefits of this pan-Neisseria strategy by evaluating three contemporary treatment options for N. gonorrhoeae-ceftriaxone plus azithromycin, monotherapy with ceftriaxone and zoliflodacin.