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Summary: Chlamydia trachomatis is the most common sexually transmitted pathogen globally, causing serious health problems and representing a burden on public health. A new variant of C. trachomatis (nvCT) that carries mutations (C1514T, C1515T and G1523A) in the 23S rRNA gene has eluded detection in Aptima Combo 2 assays. This has led to false negatives in diagnostics tests and poses a challenge for C. trachomatis diagnostics on a global level. In this study, we developed a simple and cost‐effective assay to identify C. trachomatis, with a potential application to screen for nvCT. We developed a screening assay based on high‐resolution melting (HRM), targeting the 23S rRNA gene and cryptic plasmid. To evaluate the performance of the assay, 404 archived C. trachomatis DNA specimens and 570 extracted clinical specimens were analysed. Our HRM assay not only identified C. trachomatis in clinical specimens, but also correctly differentiated nvCT carrying C1514T, C1515T and G1523A mutations from the wild‐type. We observed no cross‐reactions with other clinically related agents, and the limit of detection was 11.26 (95% CI; 7.61–31.82) copies per reaction. Implementation of this screening assay could reduce detection times and costs for C. trachomatis diagnoses, and facilitate increased research on the presence and monitoring of nvCT. [ABSTRACT FROM AUTHOR]

Introduction: This study aims to determine the etiological, sociodemographic, and clinical characteristics of STIs, and the level of resistance in M. genitalium in Shenzhen, a representative first-tier city of southern China., Methods: A multicenter cross-sectional study was conducted and 7886 sexually active participants attending STI-related departments were involved from 22 hospitals. Nine STI-related organisms including N. gonorrhoeae , C. trachomatis , T. vaginalis , M. genitalium , HSV-1, HSV-2, M. hominis , U. parvum , and U. urealyticum were screened., Results: Being single or divorced was associated with increased detection of N. gonorrhoeae , C . trachomatis , M. genitalium , HSV-1, HSV-2 and M. hominis . Lower education level was associated with increased detection of C. trachomatis , HSV-2 and M. hominis . No insurance coverage was an independent risk factor for T. vaginalis , M. hominis and U. parvum positivity. Three resistance-determining regions related to macrolide and fluoroquinolone were sequenced in 154 M. genitalium positive samples, among which 90.3% harbored mutations related to macrolide or fluroquinolone resistance and 67.5% were multidrug-resistant M. genitalium . A2072G in 23S rRNA and Ser83Ile in parC were the most common mutations. M. hominis was associated with manifestations of bacterial vaginosis in female and epididymitis in male., Conclusions: Single or divorced individuals, those with lower education level and individuals without insurance are higher-risk key populations for STIs. The prevalence of antimicrobial-resistant M. genitalium in Shenzhen is high. Detection of M. hominis increased significantly with lower education level and no health insurance coverage, and it is associated with bacterial vaginosis or epididymitis, indicating that M. hominis deserves further attention., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Wang, Zhang, Xiu, Li, Zeng, Li, Cai and Peng.)

The growing antimicrobial resistance (AMR) in Neisseria gonorrhoeae is a serious global threat to gonococcal therapy. Molecular typing is an ideal tool to reveal the association between specific genotype and resistance phenotype that provides effective data for tracking the transmission of resistant clones of N. gonorrhoeae In our study, we aimed to describe the molecular epidemiology of AMR and the distribution of resistance-associated genotypes in Shenzhen during 2014-2018. In total, 909 isolates were collected from Shenzhen from 2014-2018. Two typing schemes, multilocus sequence typing (MLST) and N. gonorrhoeae Sequence Typing for Antimicrobial Resistance (NG-STAR), were performed for all isolates. The distribution of resistance-associated genotypes was described using goeBURST analysis combined with data of logistic regression. Among 909 isolates, ST 8123 , ST 7363 , ST 1901 , ST 7365 , and ST 7360 were most the common MLST sequence types (STs), and ST 348 , ST 2473 , ST 497 , and ST 199 were the most prevalent NG-STAR STs. The logistic regression analysis showed that NG-STAR ST497 , MLST ST7365 , and MLST ST7360 were typically associated with decreased susceptibility to ceftriaxone. Furthermore, the internationally spreading ESC-resistant clone MLST ST1901 has been prevalent at least in 2014 in Shenzhen and showed a significant increase during 2014-2018. Additionally, MLST ST7363 owns the potential to become the next internationally spreading ceftriaxone-resistant ST. In conclusions, we performed a comprehensive epidemiological study to explore the correlation between AMR and specific STs, which provided important data for future studies of the molecular epidemiology of AMR in N. gonorrhoeae Besides, these findings provide insight for adjusting surveillance strategies and therapy management in Shenzhen., (Copyright © 2021 American Society for Microbiology.)

Background: Antimicrobial resistance (AMR) of Neisseria gonorrhoeae has spread worldwide. Rapid and comprehensive methods are needed to describe N. gonorrhoeae AMR profiles accurately. A method based on multiplex amplicon sequencing was developed to simultaneously sequence 13 genes related to AMR in N. gonorrhoeae directly from clinical samples., Methods: Nine N. gonorrhoeae strains were used for the establishment and validation of the method. Eleven urethral swabs and their corresponding cultured isolates were matched as pairs to determine the accuracy of the method. Mock samples with different dilutions were prepared to determine the sensitivity of the method. Five nongonococcal Neisseria strains and 24 N. gonorrhoeae negative clinical samples were used to evaluate the cross-reactivity. Finally, the method was applied to 64 clinical samples to assess its performance., Results: Using Sanger sequencing as a reference method, sequences recovered from amplicon sequencing had a base accuracy of over 99.5% and the AMR sites were correctly identified. The limit of detection (LOD) was lower than 31 copies/reaction. No significant cross-reactivity was observed. Furthermore, target genes were successfully recovered from 64 clinical samples including 9 urines, demonstrating this method could be used in different types of samples. For clinical samples, the results can be obtained within a time frame of 7 h 40 min to 10 h 40 min, while for isolates, the turnaround time was approximately 2 h shorter., Conclusions: This method can serve as a versatile and convenient culture-free diagnostic method with the advantages of high sensitivity and accuracy., (© American Association for Clinical Chemistry 2020. All rights reserved. For permissions, please email: journals.permissions@oup.com.)