Impact of mutations in the mtrR, rpdlVD and rrl genes on azithromycin resistance in Neisseria gonorrhoeae.

INTRODUCTION: Bacterial sexually transmitted infections (STIs) pose a major public health problem. The emergence of antibiotic-resistant strains of Neisseria gonorrhoeae represents a serious threat to successful treatment and epidemiological control. The first extensively drug-resistant (XDR) strains (ceftriaxone-resistant and high-level azithromycin-resistant [HLR AZY]) have been reported. AIMS: To identify molecular mechanisms implicated in azithromycin resistance in strains isolated from patients over a three-year period in a university hospital in Switzerland. MATERIAL AND METHODS: From January 2020 to December 2022, 34 isolates (one per patient) were recovered from samples analyzed at the University Hospital of Lausanne. Eight genes involved in azithromycin resistance were sequenced: mtrR repressor (mtrCDE operon repressor) and his promotor mtrR-pr, rplD gene (L4 ribosomal protein), rplV gene (L22 ribosomal protein) and the four alleles of the rrl gene (23S rRNA). RESULTS: With a cutoff value of 1 mg/L, 15 isolates were considered as being resistant to azithromycin, whereas the remaining 19 were susceptible. The C2597T mutation in 3 or 4 of the rrl allele confer a medium-level resistance to azithromycin (MIC = 16 mg/L, N = 2). The following mutations were significantly associated with MIC values ≥1 mg/L: the three mutations V125A, A147G, R157Q in the rplD gene (N = 10) and a substitution A->C in the mtrR promotor (N = 9). Specific mutations in the mtrR repressor and its promotor were observed in both susceptible and resistant isolates. CONCLUSIONS: Resistance to azithromycin was explained by the presence of mutations in many different copies of 23S RNA ribosomal genes and their regulatory genes. Other mutations, previously reported to be associated with azithromycin resistance, were documented in both susceptible and resistant isolates, suggesting they play little role, if any, in azithromycin resistance.

First-line treatment with ceftriaxone for Neisseria gonorrhoeae infection less likely to be prescribed to patients with a penicillin allergy label: a retrospective audit of medical records.

Background Gonorrhoea notifications have increased substantially in Australia over the past decade. Neisseria gonorrhoeae is already highly resistant to several antibiotics and so, alternatives to first-line treatment are generally strongly discouraged. The penicillin allergy label (AL) on patient medical records has previously been shown to influence prescribing practices, to the detriment of best-practice management and antimicrobial stewardship. This study aimed to understand how the penicillin AL influences antibiotic selection for gonorrhoea treatment at Canberra Sexual Health Centre. Methods A retrospective chart audit of gonorrhoea cases treated at Canberra Sexual Health Centre between January 2020 and October 2023 (n =619 patients, n =728 cases). Antibiotic selection was assessed according to penicillin AL status. Ceftriaxone selection was assessed according to penicillin allergy severity reported in the medical records and as determined using a validated antibiotic allergy assessment tool. Results Cases with a penicillin AL were more likely to receive antibiotics other than ceftriaxone (n =7/41, 17.1%) than cases without the label (n =8/687, 1.2%, P n =28/41, 68.3%) to apply the assessment tool. Those reported as low-severity in the records were more likely to receive ceftriaxone (n =21/22, 95.5%) than those reported as moderate-high (n =7/11, 63.6%) or unreported (n =6/8, 0.75%). Conclusions Treatment of gonorrhoea in outpatient settings requires an understanding of penicillin allergy, and the ability to quickly and accurately identify penicillin-AL patients who can safely tolerate ceftriaxone. Institutionally endorsed penicillin allergy de-labelling protocols and access to easy-to-navigate prescribing advice within national sexually transmitted infection management guidelines would support this.

Data quality assessment of the Enhanced Gonococcal Antimicrobial Surveillance Programme (EGASP), Thailand, 2015-2021.

BACKGROUND: Quality assessments of gonococcal surveillance data are critical to improve data validity and to enhance the value of surveillance findings. Detecting data errors by systematic audits identifies areas for quality improvement. We designed and implemented an internal audit process to evaluate the accuracy and completeness of surveillance data for the Thailand Enhanced Gonococcal Antimicrobial Surveillance Programme (EGASP). METHODS: We conducted a data quality audit of source records by comparison with the data stored in the EGASP database for five audit cycles from 2015-2021. Ten percent of culture-confirmed cases of Neisseria gonorrhoeae were randomly sampled along with any cases identified with elevated antimicrobial susceptibility testing results and cases with repeat infections. Incorrect and incomplete data were investigated, and corrective action and preventive actions (CAPA) were implemented. Accuracy was defined as the percentage of identical data in both the source records and the database. Completeness was defined as the percentage of non-missing data from either the source document or the database. Statistical analyses were performed using the t-test and the Fisher's exact test. RESULTS: We sampled and reviewed 70, 162, 85, 68, and 46 EGASP records during the five audit cycles. Overall accuracy and completeness in the five audit cycles ranged from 93.6% to 99.4% and 95.0% to 99.9%, respectively. Overall, completeness was significantly higher than accuracy (p = 0.017). For each laboratory and clinical data element, concordance was >85% in all audit cycles except for two laboratory data elements in two audit cycles. These elements significantly improved following identification and CAPA implementation. DISCUSSION: We found a high level of data accuracy and completeness in the five audit cycles. The implementation of the audit process identified areas for improvement. Systematic quality assessments of laboratory and clinical data ensure high quality EGASP surveillance data to monitor for antimicrobial resistant Neisseria gonorrhoeae in Thailand.

Susceptibility of Neisseria gonorrhoeae against a dual treatment antibiotics regimen in primary health centres in Surabaya, Indonesia.

BACKGROUND AND OBJECTIVES: There were 82.4 million new gonorrhoea cases worldwide in 2020. Dual treatment with ceftriaxone or cefixime and azithromycin or doxycycline is currently recommended for gonorrhoea in Indonesia. However, reduced susceptibility and resistance to cephalosporins and azithromycin are increasing. We evaluated the susceptibility pattern of Neisseria gonorrhoeae to cefixime, ceftriaxone, azithromycin and doxycycline. METHOD: N. gonorrhoeae isolates were obtained from 19 male participants with clinically and laboratory-confirmed gonorrhoea. Antibiotic susceptibility testing was conducted by disc diffusion and interpreted according to Clinical and Laboratory Standards Institute and Centers for Disease Control and Prevention criteria. RESULTS: Reduced susceptibility or resistance was observed against doxycycline in 19 isolates (100%), cefixime in six (31.6%), ceftriaxone in three (15.8%) and azithromycin in zero (0%) isolates. DISCUSSION: A dual treatment regimen with ceftriaxone and azithromycin can still be recommended as first-line therapy for gonorrhoea in Indonesia. Antibiotic susceptibility surveillance of N. gonorrhoeae should be routinely conducted.

Surge in Ceftriaxone-Resistant Neisseria gonorrhoeae FC428-Like Strains, Asia-Pacific Region, 2015-2022.

Ceftriaxone-resistant Neisseria gonorrhoeae FC428-like strains have disseminated across the Asia-Pacific region, with a continuous rise in prevalence during 2015-2022. To mitigate the effect of these strains, we advocate for enhanced molecular diagnostics, expanded surveillance networks, and a regionally coordinated effort to combat the global spread of FC428-like strains.

Assessing thresholds of resistance prevalence at which empiric treatment of gonorrhea should change among men who have sex with men in the US: A cost-effectiveness analysis.

BACKGROUND: Since common diagnostic tests for gonorrhea do not provide information about susceptibility to antibiotics, treatment of gonorrhea remains empiric. Antibiotics used for empiric therapy are usually changed once resistance prevalence exceeds a certain threshold (e.g., 5%). A low switch threshold is intended to increase the probability that an infection is successfully treated with the first-line antibiotic, but it could also increase the pace at which recommendations are switched to newer antibiotics. Little is known about the impact of changing the switch threshold on the incidence of gonorrhea, the rate of treatment failure, and the overall cost and quality-adjusted life-years (QALYs) associated with gonorrhea. METHODS AND FINDINGS: We developed a transmission model of gonococcal infection with multiple resistant strains to project gonorrhea-associated costs and loss in QALYs under different switch thresholds among men who have sex with men (MSM) in the United States. We accounted for the costs and disutilities associated with symptoms, diagnosis, treatment, and sequelae, and combined costs and QALYs in a measure of net health benefit (NHB). Our results suggest that under a scenario where 3 antibiotics are available over the next 50 years (2 suitable for the first-line therapy of gonorrhea and 1 suitable only for the retreatment of resistant infections), changing the switch threshold between 1% and 10% does not meaningfully impact the annual number of gonorrhea cases, total costs, or total QALY losses associated with gonorrhea. However, if a new antibiotic is to become available in the future, choosing a lower switch threshold could improve the population NHB. If in addition, drug-susceptibility testing (DST) is available to inform retreatment regimens after unsuccessful first-line therapy, setting the switch threshold at 1% to 2% is expected to maximize the population NHB. A limitation of our study is that our analysis only focuses on the MSM population and does not consider the influence of interventions such as vaccine and common use of rapid drugs susceptibility tests to inform first-line therapy. CONCLUSIONS: Changing the switch threshold for first-line antibiotics may not substantially change the health and financial outcomes associated with gonorrhea. However, the switch threshold could be reduced when newer antibiotics are expected to become available soon or when in addition to future novel antibiotics, DST is also available to inform retreatment regimens.

Tricuspid valve infective endocarditis in disseminated gonococcal infection (DGI).

SummaryWe describe a case of culture-negative infective endocarditis due to Neisseria gonorrhoeae, where the application of metagenomics shotgun sequencing in blood played a pivotal role in elucidating the underlying aetiology, guiding targeted therapy and ultimately resulting in the patient's complete recovery. Beyond its immediate clinical impact, prompt treatment bears significant implications for public health. The utilisation of molecular testing emerges as a valuable strategy to enhance diagnostic accuracy, particularly in cases involving fastidious organisms that are infrequently associated with infective endocarditis.

Combination of compound screening with an animal model identifies pentamidine to prevent Chlamydia trachomatis infection.

Chlamydia trachomatis (Ct) is the most common cause for bacterial sexually transmitted infections (STIs) worldwide with a tremendous impact on public health. With the aim to unravel novel targets of the chlamydia life cycle, we screen a compound library and identify 28 agents to significantly reduce Ct growth. The known anti-infective agent pentamidine-one of the top candidates of the screen-shows anti-chlamydia activity in low concentrations by changing the metabolism of host cells impairing chlamydia growth. Furthermore, it effectively decreases the Ct burden upon local or systemic application in mice. Pentamidine also inhibits the growth of Neisseria gonorrhea (Ng), which is a common co-infection of Ct. The conducted compound screen is powerful in exploring antimicrobial compounds against Ct in a medium-throughput format. Following thorough in vitro and in vivo assessments, pentamidine emerges as a promising agent for topical prophylaxis or treatment against Ct and possibly other bacterial STIs.

Gonorrhoea treatment guideline compliance and influence factors in Guangdong province, China: a cross-sectional survey.

BACKGROUND: The indiscriminate use of antibiotics has accelerated antimicrobial resistance (AMR) in Neisseria gonorrhoeae (NG), emphasising the need to follow treatment guidelines. This study aimed to assess the rate of adherence to standard treatment among patients with gonorrhoea and identify influencing factors. METHODS: A survey was conducted in Guangdong province, China, involving uncomplicated gonorrhoea cases registered in the Chinese Information System for Disease Control and Prevention. Data on demographic characteristics and medical information were collected to determine the standard treatment rate, defined as the proportion of patients receiving treatment according to national guidelines (ie, a single dose of ceftriaxone 250 mg, spectinomycin 2 g, cefotaxime 1 g or other third-generation cephalosporins). Medication choices were documented. χ² tests and multilevel logistic regression were used to analyse factors associated with standard treatment. RESULTS: The survey included 2424 patients with gonorrhoea from 59 hospitals. The standard treatment rate was 30.7% (743/2424), with 36.2% for females and 29.6% for males. Common reasons for substandard treatment included the use of non-guideline medications (42.3%, 710/1681) and incorrect dosing (36.2%, 605/1681). Factors associated with the standard treatment rate included gender, address, educational level, department, physicians' training, number of diagnosed gonorrhoea cases and hospital level. CONCLUSION: The standard treatment rate for gonorrhoea in Guangdong province, China, is below expectations. Comprehensive measures, such as establishing a goal-directed monitoring system and implementing promotional activities, are needed to improve adherence to treatment guidelines.

Economic evaluation alongside a clinical trial of near-to-patient testing for sexually transmitted infections.

BACKGROUND: Current clinical care for common bacterial STIs (Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG) and Mycoplasma genitalium (MG)) involves empiric antimicrobial therapy when clients are symptomatic, or if asymptomatic, waiting for laboratory testing and recall if indicated. Near-to-patient testing (NPT) can improve pathogen-specific prescribing and reduce unnecessary or inappropriate antibiotic use in treating sexually transmitted infections (STI) by providing same-day delivery of results and treatment. METHODS: We compared the economic cost of NPT to current clinic practice for managing clients with suspected proctitis, non-gonococcal urethritis (NGU), or as an STI contact, from a health provider's perspective. With a microsimulation of 1000 clients, we calculated the cost per client tested and per STI- and pathogen- detected for each testing strategy. Sensitivity analyses were conducted to assess the robustness of the main outcomes. Costs are reported as Australian dollars (2023). RESULTS: In the standard care arm, cost per client tested for proctitis, NGU in men who have sex with men (MSM) and heterosexual men were the highest at $247.96 (95% Prediction Interval (PI): 246.77-249.15), $204.23 (95% PI: 202.70-205.75) and $195.01 (95% PI: 193.81-196.21) respectively. Comparatively, in the NPT arm, it costs $162.36 (95% PI: 161.43-163.28), $158.39 (95% PI: 157.62-159.15) and $149.17 (95% PI: 148.62-149.73), respectively. Using NPT resulted in cost savings of 34.52%, 22.45% and 23.51%, respectively. Among all the testing strategies, substantial difference in cost per client tested between the standard care arm and the NPT arm was observed for contacts of CT or NG, varying from 27.37% to 35.28%. CONCLUSION: We found that NPT is cost-saving compared with standard clinical care for individuals with STI symptoms and sexual contacts of CT, NG, and MG.

Antimicrobial Susceptibility and Characteristics of Neisseria gonorrhoeae Isolates from Puerto Rico, 2012-2017.

OBJECTIVE: Monitoring the susceptibility patterns of Neisseria gonorrhoeae is essential for the continuing compliance with current treatment recommendations. Puerto Rico conducts susceptibility tests on N. gonorrhoeae; however, trends on antimicrobial resistance in the island have not been reported since the mid 80's. METHODS: We performed a secondary analysis of a national data repository on the antimicrobial susceptibility of N. gonorrhoeae isolates between 2012 and 2017; a period of time when the CDC recommended a single dose of ceftriaxone and azithromycin for the treatment of uncomplicated gonorrhea. Data on susceptibility to eight antibiotics using the standard disk diffusion method was obtained for 30.0% (84/276) of the samples collected from the Sexually Transmitted Disease clinics in Puerto Rico. We also performed patient demographic analyses linked to resistance. RESULTS: Rates of resistance to ceftriaxone and azithromycin were 0% and 4.0% (2/50), respectively. The percentage of isolates resistant to antimicrobials no longer recommended in Puerto Rico, such as tetracycline, ciprofloxacin, and penicillin, was 86.0% (43/50), 76.0% (38/50), and 38.0% (19/50), respectively. Prevalence of resistant N. gonorrhoeae was higher among men who have sex with men, MSM (79%, 37/47). DISCUSSION: Lack of resistance to ceftriaxone and slow emergence of azithromycin resistance was identified from 2012-2017. It is imperative to continue the surveillance for emerging patterns of resistance, especially for ceftriaxone, as it is part of the current treatment guidelines. Therefore, protocols for culture based surveillance, including sample transport and processing, should be strengthened to ensure quality assured epidemiology of gonococcal resistance in Puerto Rico.

Gonococcal mastitis. / Gonokokkmastitt.

A young woman experienced pain and swelling in a non-lactating breast. The culture test result showed an unusual microbe, which is increasingly prevalent in Norway and internationally.

Management of Neisseria gonorrhoeae infection: from drug resistance to drug repurposing.

INTRODUCTION: Neisseria gonorrhoeae is a common sexually transmitted disease connected with extensive drug resistance to many antibiotics. Presently, only expanded spectrum cephalosporins (ceftriaxone and cefixime) and azithromycin remain useful for its management. AREAS COVERED: New chemotypes for the classical antibiotic drug target gyrase/topoisomerase IV afforded inhibitors with potent binding to these enzymes, with an inhibition mechanism distinct from that of fluoroquinolones, and thus less prone to mutations. The α-carbonic anhydrase from the genome of this bacterium (NgCAα) was also validated as an antibacterial target. EXPERT OPINION: By exploiting different subunits from the gyrase/topoisomerase IV as well as new chemotypes, two new antibiotics reached Phase II/III clinical trials, zoliflodacin and gepotidacin. They possess a novel inhibition mechanism, binding in distinct parts of the enzyme compared to the fluoroquinolones. Other chemotypes with inhibitory activity in these enzymes were also reported. NgCAα inhibitors belonging to a variety of classes were obtained, with several sulfonamides showing MIC values in the range of 0.25-4 µg/mL and significant activity in animal models of this infection. Acetazolamide and similar CA inhibitors might thus be repurposed as antiinfectives. The scientific/patent literature has been searched for on PubMed, ScienceDirect, Espacenet, and PatentGuru, from 2016 to 2024.

World Health Organization Enhanced Gonococcal Antimicrobial Surveillance Programme, Cambodia, 2023.

To determine antimicrobial susceptibility of Neisseria gonorrhoeae, we analyzed phenotypes and genomes of 72 isolates collected in Cambodia in 2023. Of those, 9/72 (12.5%) were extensively drug resistant, a 3-fold increase from 2022. Genomic analysis confirmed expansion of newly emerging resistant clones and ongoing resistance emergence across new phylogenetic backbones.

Australian Gonococcal Surveillance Programme, 1 October to 31 December 2023.

Abstract: The Australian National Neisseria Network (NNN) comprises reference laboratories in each state and territory that report data on antimicrobial susceptibility testing to an agreed group of antimicrobial agents for the Australian Gonococcal Surveillance Programme (AGSP). The AGSP data are presented quarterly in tabulated form, as well as in the AGSP annual report. This report presents national gonococcal antimicrobial resistance surveillance data from 1 October to 31 December 2023.

Multidrug-Resistant "Super Gonorrhea" Rallies Multipronged Effort.

This Medical News article discusses approaches to slow the spread of antimicrobial resistance in Neisseria gonorrhoeae.

Can we use azithromycin eye drops for gonococcal ophthalmia prophylaxis in the United States?

INTRODUCTION: Neonatal ocular prophylaxis with 0.5% erythromycin ophthalmic ointment is mandated by law in many U.S. states despite its lack of efficacy in preventing chlamydial ophthalmia and the low incidence of gonococcal ophthalmia today. The current shortage of 0.5% erythromycin ophthalmic ointment is bringing into question what alternatives exist for neonatal ocular prophylaxis for the prevention of gonococcal ophthalmia. Providers in states with mandates are concerned with the implications of administering intramuscular ceftriaxone to every newborn. Azithromycin eye drops are being considered as an alternative. AREAS COVERED: This article discusses 1% azithromycin eye drops as an alternative to 0.5% erythromycin ophthalmic ointment. Clinical experience, side effects, resistance, logistics, pharmacokinetics, and pharmacodynamics are considered. EXPERT OPINION: Azithromycin eye drops are not an appropriate alternative to 0.5% erythromycin ophthalmic ointment for ocular prophylaxis. Prenatal screening and treatment of pregnant women is the most effective way to prevent neonatal ophthalmia. Mandates for universal prophylaxis should be withdrawn to avoid unnecessary medication administration, healthcare costs, and potential harm.

Could the effect of antimicrobials on antimicrobial resistance be saturated at high-antimicrobial consumption? A comparison of the MORDOR and ResistAZM studies.

OBJECTIVES: Antimicrobial resistance poses a considerable threat in high-antimicrobial-consumption populations, such as men who have sex with men (MSM) taking HIV pre-exposure prophylaxis. While the ResistAZM trial found no increase in macrolide resistance genes in MSM with gonorrhea after azithromycin treatment, the MORDOR trial observed an increase in these genes after mass azithromycin distribution. We hypothesized that this could be due to saturation of the resistome. To test this hypothesis, we compared the abundance of macrolide resistance determinants in anorectal samples between the baselines of the two trials. METHODS: Shotgun metagenome reads from the anorectal baseline samples from the ResistAZM (n = 42) and MORDOR (n = 30) trials were analyzed using AMRPlusPlus. Nonhost reads were mapped to the MEGARes database to detect antibiotic resistance genes (ARG). Antimicrobial resistance (AMR) was normalized using cumulative sum scaling, and ARG abundance was estimated. RESULTS: Macrolide, lincosamides, and streptogramins determinants were approximately 10-fold more abundant in the ResistAZM than the MORDOR samples (P ≤ 0.001). CONCLUSION: The findings are compatible with our hypothesis. Thus, in populations with high-antimicrobial use, the relationship between antimicrobial consumption and AMR may be diminished due to saturation. These findings are vital for future studies investigating the resistogencity of novel interventions, such as doxycycline post-exposure prophylaxis, in populations with high preceding consumption of antimicrobials.