Comparison between Aptima Assays (Hologic) and the Allplex STI Essential Assay (Seegene) for the diagnosis of Sexually transmitted infections

Prevalence of sexually transmitted infections and associated risk factors among female sex workers in Guinea-Bissau

OBJECTIVE

To estimate the prevalence of the curable sexually transmitted infections (STIs) Chlamydia trachomatis, Neisseria gonorrhoeae, Mycoplasma genitalium, Trichomonas vaginalis and Treponema pallidum, to identify associated risk factors and to assess ciprofloxacin resistance in N. gonorrhoeae-positive specimens among female sex workers (FSWs) in Guinea-Bissau.

METHODS

For this cross-sectional study, FSWs were recruited from October 2014 to May 2019. A questionnaire on STI risk factors was completed by the study participants, and the women were asked to provide a vaginal swab for nucleic acid amplification tests for C. trachomatis, N. gonorrhoeae, M. genitalium, T. vaginalis (Aptima, Hologica), as well as a blood sample for T. pallidum serological testing and discriminatory HIV-testing. The prevalence of STIs was determined, and multivariate logistic regression was used to identify STI risk factors.

RESULTS

The study included 467 women. The prevalence of current infection with any curable STI was 46.7%, and the most common pathogen was T. vaginalis (26.3%), followed by M. genitalium (21.9%), C. trachomatis (11.8%), N. gonorrhoeae (10.1%) and T. pallidum (2.8%). The proportion of asymptomatic infections among the diagnosed STIs was 61.8%, 61.5%, 55.3%, 55.3% and 52.2% for C. trachomatis, T. pallidum, N. gonorrhoeae, T. vaginalis and M. genitalium, respectively. The prevalence of the gyrA S91F mutation conferring ciprofloxacin resistance in N. gonorrhoeae-positive specimens was 84.0%. Significant risk factors for having a curable STI were age and HIV-1 infection, while use of female condoms was a protective factor.

CONCLUSION

This study demonstrated that the prevalence of curable STIs was high among FSWs in Guinea-Bissau during the study period, indicating an unmet need for STI services. Moreover, the results indicated that symptomatic treatment might be insufficient, highlighting a need for periodic aetiological testing to facilitate detection of asymptomatic as well as symptomatic STIs to stop ongoing transmission.

Prevalence of Chlamydia trachomatis and Neisseria gonorrhoeae infections among sexual assault victims referred to three French clinical forensic units

BACKGROUND

Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) infections are the most common bacterial sexually transmitted infections (STIs) worldwide. These STIs are frequently asymptomatic, which often delays diagnosis and treatment with the risk of serious long-term complications. Current French recommendations call for targeted screening of populations considered to be at risk, including victims of sexual assault. However, no recent data on the prevalence of these STIs in this population are available in France. The aim of this study was therefore to determine the prevalence of CT/NG infections among victims of sexual assault attending three Clinical Forensic Units (CFUs).

METHODS

We retrospectively reviewed the forensic records of patients aged over 12 years reporting a sexual assault and referred between January 1, 2020 and December 31, 2021 to the CFU of Montpellier, Angers or Saint-Denis de La Réunion. Patients who had been screened for CT and NG infections were included.

RESULTS

341 alleged victims of sexual assault (324 women, 17 men, median age = 23 years) were screened for CT/NG STIs during the inclusion period (Montpellier, n=196; Angers, n=63; Saint-Denis, n=82). The median time between the sexual assault and the examination was 1 day. CT and NG were detected in 28 patients (8.2 %) and 8 patients (2.3 %) respectively, with no men tested positive. Positive results concerned genital samples, except for two CT-positive anorectal samples and one NG-positive oropharyngeal sample. Two patients (0.6 %) were co-infected with CT/NG. The overall prevalence of CT/NG STIs was 10.0 % and was higher in the 18-24 age group, reaching 13.2 % for CT.

CONCLUSIONS

This multicenter study confirms the high prevalence of CT/NG STIs in victims of sexual assault, and the vulnerability of the youngest age groups to these infections. Systematic screening for CT/NG STIs at the time of the forensic examination is the key to early diagnosis and effective treatment to prevent transmission and subsequent complications in these patients.

Detection of Trichomonas vaginalis by Allplex™ STI Essential Assay (Seegene) in clinical samples from the Brazilian public health system users

The failures in Trichomonas vaginalis (TV) infection diagnosis leave more than half of cases unidentified. In this report, urine and vaginal discharge samples were analyzed by wet mount, culture examination, and real-time PCR by Allplex™ (Seegene®) kit, in a population assisted by the Brazilian Public Health System. From 747 samples, 2.81% were positive for TV in wet mount and culture, and 3.88% by Allplex™. Samples kept at - 80 ºC for 22 months did not impair the PCR technique. The sensitivity for wet mount, culture, and Allplex™ was 72, 100, and 100%, respectively. Allplex™ technique showed highest detection of TV.

Estimating the prevalence of two or more diseases using outcomes from multiplex group testing

When screening a population for infectious diseases, pooling individual specimens (e.g., blood, swabs, urine, etc.) can provide enormous cost savings when compared to testing specimens individually. In the biostatistics literature, testing pools of specimens is commonly known as group testing or pooled testing. Although estimating a population-level prevalence with group testing data has received a large amount of attention, most of this work has focused on applications involving a single disease, such as human immunodeficiency virus. Modern methods of screening now involve testing pools and individuals for multiple diseases simultaneously through the use of multiplex assays. Hou et al. (2017, Biometrics, 73, 656-665) and Hou et al. (2020, Biostatistics, 21, 417-431) recently proposed group testing protocols for multiplex assays and derived relevant case identification characteristics, including the expected number of tests and those which quantify classification accuracy. In this article, we describe Bayesian methods to estimate population-level disease probabilities from implementing these protocols or any other multiplex group testing protocol which might be carried out in practice. Our estimation methods can be used with multiplex assays for two or more diseases while incorporating the possibility of test misclassification for each disease. We use chlamydia and gonorrhea testing data collected at the State Hygienic Laboratory at the University of Iowa to illustrate our work. We also provide an online R resource practitioners can use to implement the methods in this article.

A retrospective evaluation of the Euroarray STI-11 multiplex system for the detection of eight STI causing agents

With an incidence of more than > 1,000,000/day, sexually transmitted diseases remain a major challenge for health care systems worldwide. To reduce disease burden, complications, and spread, rapid diagnosis permitting early therapy is pivotal. The range of pathogens is wide and co-infections are common. This complicates pre-analytics, which are based on different laboratory techniques with potentially long turnaround times, e.g., cultivation and multistep serologies. Multiplex PCR provides the opportunity to overcome these limitations. In this study, we evaluated a novel assay, the Euroarray STI-11 microarray (EA; Euroimmun Medizinische Labordiagnostika), for the detection of eight obligate or facultative pathogens. Three-hundred-thirteen clinical specimens, which had been tested and pre-characterized for STI causing agents as part of routine diagnostics, were used as cases and controls in this retrospective study. The EA detected 34/44 Chlamydia trachomatis, 48/50 HSV-1, 50/50 HSV-2, 48/48 Mycoplasma hominis, 45/47 Neisseria gonorrhoeae, 9/11 Treponema pallidum, 46/46 Ureaplasma parvum, and 49/49 Ureaplasma urealyticum infections, respectively. 293 samples were EA positive, with polymicrobial infections (positive for two to six microbial or viral agents) detected in 130/293 cases. Specificities were 100% in the respective control groups (n = 18-48 depending on targeted pathogen) except for N. gonorrhoeae (25/26) and U. urealyticum (44/45). The broad spectrum of obligate and facultative pathogens targeted by the EA makes it a valuable tool in the setting of STI diagnostics and surveillance. The test has the potential to diagnose diseases neglected or overlooked in routine clinical practice. Besides a low sensitivity for C. trachomatis, the EA demonstrated high performance for all analyzed parameters. Further studies are warranted in order to capture a larger variety of the tested pathogens.

Latest Advances in Laboratory Detection of Mycoplasma genitalium

Mycoplasma genitalium is an important sexually transmitted pathogen affecting both men and women. Its extremely slow growth in vitro and very demanding culture requirements necessitate the use of molecular-based diagnostic tests for its detection in clinical specimens. The recent availability of U.S. Food and Drug Administration (FDA)-cleared commercial molecular-based assays has enabled diagnostic testing to become more widely available in the United States and no longer limited to specialized reference laboratories. Advances in the knowledge of the epidemiology and clinical significance of M. genitalium as a human pathogen made possible by the availability of molecular-based testing have led to updated guidelines for diagnostic testing and treatment that have been published in various countries. This review summarizes the importance of M. genitalium as an agent of human disease, explains the necessity of obtaining a microbiological diagnosis, describes currently available diagnostic methods, and discusses how the emergence of antimicrobial resistance has complicated treatment alternatives and influenced the development of diagnostic tests for resistance detection, with an emphasis on developments over the past few years.

Performance of two commercial multiplex polymerase chain reaction assays for the etiological diagnosis of sexually transmitted infections among men who have sex with men

BACKGROUND AND PURPOSE

This study aimed to investigate the etiologies of sexually transmitted infections (STIs) among men who have sex with men (MSM) in Taiwan.

METHODS

Two commercial assays, the BD MAX Chlamydia trachomatis (CT), Neisseria gonorrhoeae (GC), and Trichomonas vaginalis (TV) panel and the Allplex™ STI Essential assay (CT, GC, Mycoplasma genitalium [MG], Mycoplasma hominis [MH], Ureaplasma urealyticum [UU], Ureaplasma parvum [UP], and TV) were evaluated. During the first stage, urine and rectal swab samples from 168 patients were evaluated using the BD MAX assay, and the multiplex RT-PCR Allplex™ STI Essential assay was applied only to the patients with positive results on the BD MAX asay (n = 49). During the second stage, urine and rectal swab samples from 90 patients were evaluated using the BD MAX assay and the Allplex™ qPCR.

RESULTS

The Allplex qPCR identified all CT, missed one and additionally one TV from the positive samples (n = 49) by the BD MAX assay in the first stage. At the second stage, both commercial assays showed similar detection rate of CT, NG or CT/NG coinfection (11.1%, 1.1% and 4.4% by the BD MAX assay; 10.0%, 1.1% and 2.2% by the Allplex qPCR). The positivity rates of MG, MH, and UU by the Allplex qPCR were 4.4%, 2.2%, and 12.2%, respectively, for urine samples and 10%, 13.3%, and 22.2%, respectively, for anal swab samples.

CONCLUSIONS

High rates of STI-associated etiologies were observed in MSM. The positive rates were higher in rectal swabs than in urine samples.

Pooling Rectal, Pharyngeal, and Urine Samples to Detect Neisseria gonorrhoeae, Chlamydia trachomatis, and Mycoplasma genitalium Using Multiplex Polymerase Chain Reaction Is as Effective as Single-Site Testing for Men Who Have Sex With Men

Background

Screening for Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) at pharyngeal, urogenital, and anorectal sites is recommended for men who have sex with men (MSM). Pooling samples is a promising technique, but no data are available when pooled screening also includes Mycoplasma genitalium (MG). The main objective of this study was to examine the sensitivity of pooled samples for detecting CT, NG, and MG in MSM using nucleic acid amplification versus single-site testing.

Methods

In this multicenter study, MSM with a positive result for CT, NG, or MG were recalled to the clinic for treatment and were asked to participate in this study. Separate samples were sent to a central virological department that proceeded to form the pooled samples. Testing was performed using the multiplex real-time polymerase chain reaction Allplex STI Essential Assay (Seegene, Seoul, Korea), which can simultaneously detect 7 pathogens.

Results

A total of 130 MSM with at least 1 positive test for CT, NG, or MG were included. A total of 25.4% had a coinfection. The sensitivities of pooled-sample testing were 94.8% for CT, 97.0% for NG, and 92.3% for MG. Pooling failed to detect 8 infections, but pooled-sample analysis missed detecting only samples with a low bacterial load (cycle threshold >35).

Conclusions

Pooling samples from MSM to detect CT, NG, and MG is as sensitive as individual-site testing for these 3 pathogens using the Allplex assay. Missed infections with a very low bacterial load could have a low impact on further transmission.

Clinical Trials Registration. NCT03568695.

Monitoring Sexually Transmitted Infections in Cervicovaginal Exfoliative Samples in Mexican Women

Background. Globally, Sexually Transmitted Infections (STIs) are a major cause of morbidity in sexually active individuals, having complications in reproduction health and quality of life. In concordance with the Sustainable Development Goals (SDG), the study aimed to investigate the prevalence of Candida spp., Ureaplasma spp., Trichomonas vaginalis, Neisseria gonorrhoeae, Chlamydia trachomatis, HSV, and Mycoplasma spp. from cervicovaginal samples and to correlate them with the gynecological history of the patients. Methods. Our analytical, prospective, and cross-sectional study included 377 women who participated in a reproductive health campaign during 2015–2016. Anthropometric and gynecological variables were obtained. Cervicovaginal specimens were collected and analyzed with a multiplex in-house PCR to detect Candida spp., Ureaplasma spp., Trichomonas vaginalis, Neisseria gonorrhoeae, HSV, Mycoplasma spp., and Chlamydia trachomatis. Results. The positive cases were 175/377 (46.4%) to at least one of the microorganisms. The most frequent pathogen detected in this population was Ureaplasma spp. (n = 111, 29.4%), followed by Mycoplasma spp. (n = 56, 14.9%) and Candida spp. (n = 47, 12.5%); 33.7% of the positive cases were single infections, whereas 12.7% had coinfection. The multiplex PCR assay was designed targeting nucleotide sequences. Conclusions. Our data demonstrated that monitoring STIs among asymptomatic patients will encourage target programs to be more precisely and effectively implemented, as well as make these programs more affordable, to benefit society by decreasing the prevalence of STIs.

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.

Simultaneous identification of Chlamydia trachomatis, Neisseria gonorrhoeae, Mycoplasma genitalium, and Trichomonas vaginalis ‒ multicenter evaluation of the Alinity m STI assay

Objectives

Accurate and rapid diagnosis of sexually transmitted infections (STIs) is essential for timely administration of appropriate treatment and reducing the spread of the disease. We examined the performance of the new Alinity m STI assay, a qualitative real-time multiplex PCR test for simultaneous identification of Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG), Mycoplasma genitalium (MG), and Trichomonas vaginalis (TV) run on the fully automated Alinity m platform.

Methods

This international, multicenter study evaluated the accuracy, reproducibility, and clinical performance of the Alinity m STI assay compared to commonly used STI assays in a large series of patient samples encountered in clinical practice.

Results

The Alinity m STI assay identified accurately and precisely single and mixed pathogens from an analytical panel of specimens. The Alinity m STI assay demonstrated high overall agreement rates with comparator STI assays (99.6% for CT [n=2,127], 99.2% for NG [n=2,160], 97.1% for MG [n=491], and 99.4% for TV [n=313]).

Conclusions

The newly developed Alinity m STI assay accurately detects the 4 sexually transmitted target pathogens in various collection devices across clinically relevant specimen types, regardless of single or mixed infection status.

Molecular epidemiology and antimicrobials resistance mechanism of Mycoplasma genitlaium

Currently, infections caused by Mycoplasma genitalium are ones the most common sexually transmitted infections. Their prevalence is varied from 1.3% to 15.9%. Infections caused by M.genitalium may lead to urethritis in men and a wide spectrum of diseases in women. Antibiotic resistance now is one of the most emerging problems both in the scientific and in the healthcare fields. The usage of antimicrobials inhibiting cell wall synthesis for the treatment of M.genitalium is ineffective, and resistance to macrolides and fluoroquinolones is increasing rapidly. M.genitalium infections diagnostics is complicated due to specific conditions and duration of culture methods. The usage of nucleic acid amplification techniques is the most relevant for laboratory diagnostics, and is used in existing assays. This review compiles current data on the prevalence, molecular mechanisms of pathogenesis and antibiotic resistance, as well as diagnostics methods of M.genitalium.

A profile of the binx health io® molecular point-of-care test for chlamydia and gonorrhea in women and men

Introduction: Point-of-care (POC) tests for Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) are urgently needed to control the STI epidemic in order to offer patients an immediate diagnoses and accurate treatment before they leave a clinical encounter and thus reduce transmission and sequelae. Nucleic acid amplification tests (NAATs) have increased sensitivity and specificity, but very few POC assays can provide results of such tests within the usual time of the patient visit.Areas covered: This review describes the technology and performance characteristics of the binx health io® [Boston, MA] (binx io) CT/NG assay, a new rapid molecular POC assay. The assay is compared to other available molecular POC tests. We also describe the importance of time to results and assay performance for this POC assay.Expert opinion: The binx io CT/NG assay offers the ability to incorporate the use of POC tests to identify and immediately treat chlamydia and gonococcal infections into the clinical visit, which will provide improved outcomes for patients. Additional implementation studies are needed to optimize the adoption of this new test.

Mycoplasma genitalium infection in women reporting dysuria: A pilot study and review of the literature

Mycoplasma genitalium (MG) infection, a sexually transmitted infection (STI), causes cervicitis and may cause reproductive sequelae and adverse pregnancy outcomes. Some MG-infected women report dysuria, a symptom frequently attributed to urinary tract infection (UTI). Given potential MG-associated morbidity and the likelihood that UTI treatment would be ineffective in eradicating MG, an improved understanding of MG infection frequency and clinical significance in young women reporting dysuria is needed. We conducted MG testing on stored urogenital specimens collected in a pilot study on frequency of STIs in young women presenting to an emergency department for dysuria evaluation and performed a literature review on MG infection frequency in women reporting dysuria. Among 25 women presenting for dysuria evaluation in our pilot study, 6 (24.0%) had MG detected and one-third had co-infection with chlamydia and one-third with trichomoniasis; half with MG detected did not receive an antibiotic with known efficacy against MG, while the other half received azithromycin. In five studies identified in the literature review, dysuria was reported by 7%-19% of women and MG detected in 5%-22%. MG infection is common in young women with dysuria and empiric UTI treatment may not be effective against MG. Studies evaluating the clinical significance of MG infection in women reporting dysuria are needed.

Clinical validation of a new molecular test (Seegene Allplex™ Vaginitis) for the diagnosis of vaginitis: a cross-sectional study

OBJECTIVE

To validate the use of Seegene Allplex™ Vaginitis assay in the diagnosis of candidiasis, bacterial vaginosis (BV) and trichomoniasis.

DESIGN

Cross-sectional, prospective study conducted in a single centre.

SETTING

Outpatient clinic of a gynaecology department.

POPULATION

Consecutive symptomatic and asymptomatic women (18-60 years of age).

METHODS

Comparison of the assay test with the reference standards for the diagnosis of vaginitis (cultures for yeasts, Nugent for BV and nucleic acid amplification test for trichomoniasis).

MAIN OUTCOME MEASURES

Performance of the investigational assay, in comparison with the reference standards for the diagnosis of the presence of Candida spp., Trichomonas vaginalis and BV. Secondary objectives are the evaluation of the performance of the test in postmenopausal women and in symptomatic women.

RESULTS

A diagnosis of vaginitis was established in 14.0%. The global prevalences of BV, Candida spp. and T. vaginalis were 22.3%, 13.2% and 2.4%, respectively. The sensitivity and specificity of the assay test for those three causes of vaginitis were as follows: BV 91.7% and 86.6%; any Candida spp. 91.1% and 95.6%; Candida albicans 88.1% and 98.2%, non-albicans Candida 100% and 97.5%, and T. vaginalis 94.4 and 99.9%. The performance of the test was identical in the subgroup of women that reported vulvovaginal symptoms. The presence of multiple infections did not interfere with the performance of the test.

CONCLUSIONS

The Seegene Allplex™ Vaginitis assay has an excellent performance in the diagnosis of the BV and presence of Candida; the results were good for trichomoniasis, but the study was underpowered for this outcome.

TWEETABLE ABSTRACT

Seegene Allplex™ Vaginitis is an excellent option for screening and diagnosis of vaginitis.

Comparison of methods for the detection of Neisseria gonorrhoeae from South African women attending antenatal care

The detection of Neisseria gonorrhoeae using culture assays is challenging. This study aims to compare different assays for the detection of N. gonorrhoeae. This cross-sectional study was conducted at King Edward VIII Hospital and included 307 antenatal attendees, each willing to provide two endocervical swabs. The first swab was used for culture identification of N. gonorrhoeae, and the second swab was processed for the detection of the pathogen by the TaqMan quantitative polymerase chain reaction (qPCR) assay, an in-house 16S ribosomal RNA (rRNA) PCR and PCR detection of the opa gene. Culture and the nucleic acid amplification assays were each used as comparator tests in the analysis. Sensitivity and specificity were calculated using RS Studio. The prevalence of N. gonorrhoeae was 7.8%. When compared to the TaqMan assay, the 16S rRNA PCR exhibited the highest sensitivity of 62%, with a substantial level of agreement (kappa level of agreement: 0.60), followed by the opa PCR (38%) with a moderate level of agreement (0.52) and culture exhibiting the lowest sensitivity of 25% with a fair level of agreement (0.38). The diagnostic accuracy of all the assays was >90%. The TaqMan qPCR assay has the ability to serve as a future diagnostic assay for the detection of N. gonorrhoeae.

Mycoplasma genitalium Infection in Young Women Without Urogenital Symptoms Presenting to a Community-Based Emergency Department in Birmingham, Alabama

ABSTRACT

We used the Food and Drug Administration-cleared Aptima Mycoplasma genitalium assay to evaluate for M. genitalium infection among young women without urogenital symptoms presenting to a community-based emergency department in Birmingham, Alabama, between August 2016 to August 2019 for evaluation of nongynecological concerns. M. genitalium was detected in 23 (14.8%) of 155 women.

A profile of the FDA-approved and CE/IVD-marked Aptima Mycoplasma genitalium assay (Hologic) and key priorities in the management of M. genitalium infections

INTRODUCTION

Mycoplasma genitalium (MG) causes frequently asymptomatic STIs. MG prevalence figures are lacking and management is complicated by the lack of etiological diagnostics and high antimicrobial resistance in many countries. Appropriately validated, quality-assured, and FDA-approved MG diagnostic assays have been lacking.

AREAS COVERED

The clinical and analytical performance characteristics of the Aptima® MG assay, the first FDA-approved MG nucleic acid amplification test (NAAT), are summarized. Key priorities in the management and control of MG infections are also discussed.

EXPERT OPINION

Highly sensitive, specific, and quality-assured MG NAATs, e.g. the Aptima MG assay on the automated and flexible Panther® platform, are imperative to improve the management and control of MG infections internationally. This testing, combined with macrolide-resistance testing (not yet available on the Panther platform), offers a rapid, high-throughput, and appropriate diagnosis of MG. Macrolide resistance-guided sequential treatment needs to be implemented for MG infections. Dual antimicrobial therapy, novel antimicrobials and, ideally, a vaccine may become essential.

Evaluation of VIASURE Sexually Transmitted Diseases Real Time PCR Detection kit (CerTest Biotec) for the diagnostic of sexually transmitted infections

INTRODUCTION

Sexually transmitted infections (STIs) are common in our environment, and trends have been increasing in the last few years. Different methods for STIs diagnosis have been applied by microbiology laboratories over years, but real-time PCR has improved this process. Our objective was to evaluate VIASURE Sexually Transmitted Diseases Real-Time PCR Detection kit (CerTestBiotec, S.L.) comparing with the real-time PCR technique used in our laboratory (Allplex™ STI7 Essential Assay, Seegene) which was considered as reference assay.

METHODS

A total of 948 samples from different sites (vaginal, endocervical, urethral, rectal, pharyngeal swabs and urine samples) were analyzed from July to September 2018.

RESULTS

A discordant result was obtained in 4.5% (43 samples). These discrepancies were mainly observed in threshold cycle (Ct) value next to the limit of detection. The k coefficient obtained shows a very high agreement between both methods with k values from 0.92 to 0.99.

CONCLUSIONS

VIASURE Sexually Transmitted Diseases Real-Time PCR Detection kit provides a very good correlation with Allplex STI7 and therefore, it's a good tool for the diagnostic of STIs. Positive results with Ct value obtained from 35 and low amplification signal should be applied with caution and should be interpreted based on the patient's clinical data.

Clinical evaluation of the ResistancePlus MG FleXible test on the GeneXpert Infinity-48s instrument: a near-patient assay for simultaneous detection of Mycoplasma genitalium and macrolide resistance

Antibiotic resistance in Mycoplasma genitalium (MG) is rising globally, especially to macrolides. In response to this challenge, assays reporting both the detection of MG and macrolide resistance-mediating mutations (MRMM) allow therapy to be tailored to the individual. The study evaluated the performance of the ResistancePlus® MG FleXible assay for the detection of MG and MRMM. Overall, the test performed well for the detection of MG compared to the Allplex^TM STI Essential assay, used as a reference, with a kappa value of 0.926 (95% CI, 0.863-0.990). The kit also performed well for the detection of MRMM when compared with Sanger sequencing of the 23S rRNA gene, with a kappa value of 0.901 (95% CI, 0.807-0.996). The rate of MRMM in MG among the study population was 41.8%. In conclusion, the ResistancePlus® MG FleXible is a rapid, simple, and accurate cartridge-based assay for simultaneous detection of MG and MRMM in clinical settings.