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ObjectivesAntimicrobial resistance in Mycoplasma genitalium (MG) is a poorly surveyed and controlled global health concern. We evaluated the first commercial dual resistance assay, AmpliSens M. genitalium-ML/FQ-Resist-FL assay, for detection of potential macrolide and quinolone resistance-associated mutations (MRAMs and QRAMs, respectively) and estimated the prevalence of these mutations in MG in St. Petersburg, Russia.MethodsUrogenital samples positive (n=145 from 2007 to 2020) and negative (n=56 from 2021) for MG in routine diagnostics were retrospectively analysed using the AmpliSens M. genitalium-ML/FQ-Resist-FL assay (Central Research Institute of Epidemiology, Moscow, Russia) and Sanger sequencing for validation.ResultsThe AmpliSens M. genitalium-ML/FQ-Resist-FL assay detected potential MRAMs and QRAMs with sensitivities of 100% (CI95% 83.9 to 100) and 92.3% (CI95% 66.7 to 99.6) and specificities of 99.2% (CI95% 95.6 to 100) and 100% (CI95% 97.2 to 100), respectively, in clinical specimens with ≥1000 MG geq/mL. In total, MRAMs were detected in 13.8% (CI95% 9.1 to 20.3) of samples, with 23S rRNA A2058G being the most prevalent mutation (45.0% (CI95% 25.8 to 65.8)). QRAMs were found in 9.0% (CI95% 5.3 to 14.7) of samples, with S83I the most frequent mutation (53.8% (CI95% 29.1 to 76.8)). Dual resistance was observed in 5.5% (CI95% 2.8 to 10.5) of samples. Potential MRAM and dual resistance rates significantly increased over time: from 0% in 2007–2008 to 25% (ptrend=0.0009) and 10% (ptrend=0.0447), respectively, in 2018–2020. QRAM rate appeared to increase (from 0% to 13%), but significance was not reached (ptrend=0.0605).ConclusionsThe rapid increase in MG antimicrobial resistance in St. Petersburg, especially prominent for MRAMs, necessitates implementation of macrolide resistance-guided therapy in Russia. The first commercial dual resistance assay, AmpliSens M. genitalium-ML/FQ-Resist-FL assay, was sensitive and specific for detection of potential MRAMs and QRAMs and could be valuable in macrolide resistance-guided therapies and possibly for surveillance of QRAMs. International surveillance of antimicrobial resistance-associated mutations in MG, further research into clinical relevance of several parC mutations and novel treatments are essential.

Objectives Data regarding the performance characteristics of STI diagnostic tests used in Eastern Europe are very scarce. The objective of this study was to validate the AmpliSens test systems (Central Research Institute for Epidemiology, Moscow, Russia), compared to internationally acknowledged and validated tests, for genetic detection of N gonorrhoeae (NG) , C trachomatis (CT) , M genitalium (MG) and T vaginalis (TV) . Methods In total, 319 females and 127 males were recruited. For evaluation of the TV tests, additional 33 patients with diagnosed trichomoniasis at dermatovenereological dispensaries (VD) were involved. Conventional AmpliSens PCR assay (cPCR), real-time PCR assay (rtPCR), and a real-time nucleic acid sequence-based amplification assay for detection of NG or CT were evaluated. Furthermore, AmpliSens cPCR and rtPCR for detection of MG or TV were tested. As international reference tests an internationally validated real-time N gonorrhoeae porA pseudogene PCR, Cobas Amplicor CT PCR and LightMix 480HT CT PCR, MG rtPCR targeting the MgPa adhesin gene with positive results confirmed by two MG cPCRs targeting the 16S rRNA gene and MgPa gene, and a TV rtPCR targeting a TV specific repeat DNA fragment, respectively, were used. Results The overall prevalence of CT infection was 12.6%. The AmpliSens CT NAATs and the reference methods displayed a high level of concordance (97.9%–99.2%). The prevalence of NG was 2.7% and 16% among the urogenital and extragenital samples, respectively. The AmpliSens NG NAATs and the reference method displayed high level of concordance (99.4–100%). The prevalence of MG was 2.5% among females and 9.6% among males. The highest sensitivity (71.4%–100% in different specimens) was exhibited by the AmpliSens rtPCR. All tests had a 100% clinical specificity. The prevalence of TV was 1.2% among the females, and all additional VD patients tested positive. The sensitivity and the specificity of both Russian TV tests validated was 100%. Conclusion It seems clear that the biomedical industry in Eastern Europe has the potential for producing reliable reagents and tests kits at affordable prices for genetic diagnosis of STIs. This would open new perspectives for the whole region and could also be cost-effective for some other regions experiencing financial constraints. However, more comprehensive evaluations of regionally manufactured tests should be conducted according to internationally accepted guidelines.

Background Bacterial vaginosis (BV) is the most common cause of vaginal discharge in women. Since BV is associated with significant morbidity, accurate tools for diagnosing the disease are important. The Amsel criteria (AC) and Nugent score (NS) are currently used for BV diagnosis. Recently, a number of PCR-based tests providing objective, sensitive and specific BV detection have been described. This study aimed to evaluate a newly developed BV test based on quantitative detection of Gardnerella vaginalis, Atopobium vaginae, Lactobacillus spp. and total Bacteria using multiplex PCR. Methods PCR criteria were elaborated based on the relative counts of the targeted bacteria to classify vaginal microflora as BV, no BV or intermediate. Vaginal samples for the test evaluation were obtained from 274 patients addressing a gynaecologist for routine examination. All participants were of reproductive age, not pregnant and not menstruating at the time of enrollment. BV was diagnosed using the AC and NS. Results According to the NS results, 66 patients were BV positive, 156 were BV negative, and 52 were classified as intermediate. All patients positive by the NS were positive by the AC, and all patients negative by the NS were negative by the AC. Among 66 BV positive samples, 62 demonstrated PCR results corresponding to BV, and 4 samples were BV negative by PCR (94% sensitivity). Of the 156 negative samples, 151 were interpreted as BV negative using PCR criteria, and 5 samples - as BV positive (97% specificity). Conclusion A multiplex real-time PCR test for BV was developed showing 94% sensitivity and 97% specificity.

Background The new variant of Chlamydia trachomatis (nvCT), first reported in Sweden in late 2006, has so far rarely been reported outside the Nordic countries. However, knowledge of the presence of nvCT beyond these countries is limited due to the few recent studies, many laboratories still cannot detect nvCT, and the ones that can detect nvCT do mainly not distinguish it from wild type CT. The aims were to i) investigate the presence of nvCT in St. Petersburg, the largest city of the Northwest of Russia and in close proximity to Sweden, and ii) assess nucleic acid amplification tests (NAATs) used in Russia to diagnose C trachomatis infections for their ability to identify nvCT. Methods June–December 2010, consecutive samples (cervical swabs from females and urethral swabs from males) found positive for C trachomatis during routine testing with commercial PCR assays able to detect nvCT were collected. For nvCT detection, DNA was isolated using NucliSens easyMAG (bioMerieux) or QIAamp DNA mini kit (Qiagen), and analysed with an international real-time nvCT-specific PCR. C trachomatis NAATs currently used in Russia was also examined regarding their ability to detect nvCT DNA. Results During the study period, 9517 samples were submitted from patients of gynaecological, urological and STI clinics for C trachomatis testing. Of these samples, 275 (2.9%) from 198 females and 75 males were positive for C trachomatis . The mean age of the patients was 26.4 years (range 19–51 years). nvCT was detected in one sample (0.4%), which was obtained from a 23-year-old Russian woman. Genotyping using variable number of tandem repeats (VNTR) typing showed that the nvCT was indistinguishable to the previously typed nvCT samples from the Nordic countries (type 8.7.1). Six NAATs, which are used in the majority of laboratories in Russia performing C trachomatis diagnostics, were assessed for the ability to detect nvCT (Abstract P1-S1.34 table 1). All evaluated assays, with exception of the Lytech PCR, tested positive with nvCT DNA. Conclusions This study is the first report of an nvCT case in Russia, and in general in Eastern Europe, and that evaluates most C trachomatis NAATs currently used in Russia for the ability to detect nvCT. Although the prevalence of nvCT is still considered low outside Northern Europe, wider geographic spread of nvCT cannot be excluded, and therefore regular monitoring and participation in external quality assessments of diagnostic methods in use are necessary.