Evaluation of the Performance of the Cobas CT/NG Test for Use on the Cobas 6800/8800 Systems for Detection of Chlamydia trachomatis and Neisseria gonorrhoeae in Male and Female Urogenital Samples

At-home specimen self-collection as an additional testing strategy for chlamydia and gonorrhoea: a systematic literature review and meta-analysis

INTRODUCTION

Chlamydia trachomatis (Ct) and Neisseria gonorrhoeae (Ng) infections are often asymptomatic; screening increases early detection and prevents disease, sequelae and further spread. To increase Ct and Ng testing, several countries have implemented specimen self-collection outside a clinical setting. While specimen self-collection at home is highly acceptable to patients and as accurate as specimens collected by healthcare providers, this strategy is new or not being used in some countries. To understand how offering at home specimen self-collection will affect testing uptake, test results, diagnosis and linkage to care, when compared with collection in clinical settings, we conducted a systematic literature review and meta-analysis of peer-reviewed studies.

METHODS

We searched Medline, Embase, Global Health, Cochrane Library, CINAHL (EBSCOHost), Scopus and Clinical Trials. Studies were included if they directly compared specimens self-collected at home or in other non-clinical settings to specimen collection at a healthcare facility (self or clinician) for Ct and/or Ng testing and evaluated the following outcomes: uptake in testing, linkage to care, and concordance (agreement) between the two settings for the same individuals. Risk of bias (RoB) was assessed using Cochrane Risk of Bias (RoB2) tool for randomised control trials (RCTs).

RESULTS

19 studies, from 1998 to 2024, comprising 15 RCTs with a total of 62 369 participants and four concordance studies with 906 participants were included. Uptake of Ct or Ng testing was 2.61 times higher at home compared with clinical settings. There was a high concordance between specimens collected at home and in clinical settings, and linkage to care was not significantly different between the two settings (prevalence ratio 0.96 (95% CI 0.91-1.01)).

CONCLUSION

Our meta-analysis and systematic literature review show that offering self-collection of specimens at home or in other non-clinical settings could be used as an additional strategy to increase sexually transmitted infection testing in countries that have not yet widely adopted this collection method.

Accuracy of self-collected versus healthcare worker collected specimens for diagnosing sexually transmitted infections in females: an updated systematic review and meta-analysis

The use of self-collected specimens as an alternative to healthcare worker-collected specimens for diagnostic testing has gained increasing attention in recent years. This systematic review aimed to assess the diagnostic accuracy of self-collected specimens compared to healthcare worker-collected specimens across different sexually transmitted infections (STIs) including Chlamydia trachomatis (CT), human papillomavirus (HPV), Mycoplasma genitalium (MG), Neisseria gonorrhoea (NG), Treponema pallidum and Trichomonas vaginalis (TV) in females. A rigorous process was followed to screen for studies in various electronic databases. The quality of included studies was assessed using the Quality Assessment of Diagnostic Accuracy Studies 2 tool. There were no studies on syphilis that met the criteria for inclusion in the review. A total of six studies for chlamydia, five studies for HPV, four studies for MG, and seven studies for gonorrhoea and trichomoniasis were included in the review. However, not all studies were included in the sub-group meta-analysis. The analysis revealed that self-collected specimens demonstrated comparable diagnostic accuracy to healthcare worker-collected specimens across most STIs. This indicates that the diagnostic accuracy of self-collected specimens can provide accurate results and enhance access to diagnostic testing, potentially improving healthcare service delivery. Future research should further explore the diagnostic accuracy of self-collected specimens in larger and more diverse populations.

Impact of improper sample handling on Cobas CT/NG testing platform with dual swab sample collection kit for detecting Chlamydia trachomatis and Neisseria gonorrhoeae

IMPORTANCE

The importance of this observation lies in its potential to directly impact testing outcomes and patient care. By identifying improper sample handling as a contributing factor to a substantial number of invalid results, we emphasize the need for meticulous adherence to recommended protocols during sample collection. Laboratories that overlook or are unaware of such deviations may inadvertently compromise the reliability and efficacy of their diagnostic processes, leading to misdiagnoses, delayed treatment, and patient dissatisfaction.

PivNG primers and probes set used in the cobas omni Utility Channel is a reliable supplemental test for detection of Neisseria gonorrhoeae in oropharyngeal, urogenital and rectal specimens collected in cobas PCR Media

OBJECTIVE

To evaluate the clinical performance of the novel PivNG primers and probes set (PivNG test) used in the cobas omni Utility Channel for supplemental testing of Neisseria gonorrhoeae (NG).

METHODS

Oropharyngeal, urogenital and rectal samples were self-collected during routine testing at Barts Health sexual health clinics, London, UK. Samples were tested by the cobas CT/NG test and PivNG cobas omni Utility Channel test on cobas 6800/8800 Systems. Supplemental testing was carried out with the Xpert CT/NG test. PivNG overall percent agreements, positive percent agreements (PPAs)/negative percent agreements (NPAs) and positive/negative predictive values were calculated for each sample type. Microscopy and/or culture data were included for a randomised subset of concordant/discordant results, and a composite reference standard (cobas CT/NG, Xpert CT/NG and culture results) adjusted for partial verification bias was used to determine PivNG PPA and NPA.

RESULTS

Of 447 evaluable samples with valid results from all three assays (cobas CT/NG, PivNG and Xpert CT/NG), 288 (64.4%) were NG-positive by both PivNG and cobas CT/NG; 117 (26.2%) were NG-negative in both tests; and 42 (9.4%) had discordant results (with NG-negative supplementary Xpert) CT/NG results in 40/42 instances). Of 19 PivNG/Xpert CT/NG-discordant samples, 11 were confirmed NG-positive by microscopy and/or culture results. PivNG PPA and NPA were 100% and 91% for oropharyngeal swabs, 100% and 100% for vaginal swabs, 100% and 100% for male urine samples, and 100% and 97% for rectal swabs, respectively, compared with the partially adjusted composite reference standard.

CONCLUSIONS

PivNG is a reliable supplementary test with high sensitivity for confirming NG infection when used in conjunction with the cobas CT/NG test and samples collected in cobas PCR Media. Moreover, the PivNG test offers a convenient, high-throughput solution for supplemental NG testing of various sample types, with the potential to reduce the number of indeterminate reports.

[Pelvic exam in gynecology and obstetrics: Guidelines for clinical practice]

OBJECTIVE

To provide guidelines for the pelvic clinical exam in gynecology and obstetrics.

MATERIAL AND METHODS

A multidisciplinary experts consensus committee of 45 experts was formed, including representatives of patients' associations and users of the health system. The entire guidelines process was conducted independently of any funding. The authors were advised to follow the rules of the Grading of Recommendations Assessment, Development and Evaluation (GRADE®) system to guide assessment of quality of evidence. The potential drawbacks of making strong recommendations in the presence of low-quality evidence were emphasized.

METHODS

The committee studied 40 questions within 4 fields for symptomatic or asymptomatic women (emergency conditions, gynecological consultation, gynecological diseases, obstetrics, and pregnancy). Each question was formulated in a PICO (Patients, Intervention, Comparison, Outcome) format and the evidence profiles were produced. The literature review and recommendations were made according to the GRADE® methodology.

RESULTS

The experts' synthesis work and the application of the GRADE method resulted in 27 recommendations. Among the formalized recommendations, 17 present a strong agreement, 7 a weak agreement and 3 an expert consensus agreement. Thirteen questions resulted in an absence of recommendation due to lack of evidence in the literature.

CONCLUSIONS

The need to perform clinical examination in gynecological and obstetrics patients was specified in 27 pre-defined situations based on scientific evidence. More research is required to investigate the benefit in other cases.

Impact of testosterone use on the vaginal microbiota of transgender men, including susceptibility to bacterial vaginosis: study protocol for a prospective, observational study

INTRODUCTION

The effect of testosterone (T) therapy on the vaginal microbiota of transgender men (TGM) is not well characterised, although one cross-sectional study comparing the vaginal microbiota of cisgender women to TGM on T≥1 year found that, in 71% of the TGM, the vaginal microbiota was less likely to be Lactobacillus-dominated and more likely to be enriched with >30 other bacterial species, many associated with bacterial vaginosis (BV). This prospective study aims to investigate changes in the composition of the vaginal microbiota over time in TGM who retain their natal genitalia (ie, vagina) and initiate T. In addition, we will identify changes in the vaginal microbiota preceding incident BV (iBV) in this cohort while investigating behavioural factors, along with hormonal shifts, which may be associated with iBV.

METHODS AND ANALYSIS

T-naïve TGM who have not undergone gender-affirming genital surgery with normal baseline vaginal microbiota (ie, no Amsel criteria, normal Nugent Score with no Gardnerella vaginalis morphotypes) will self-collect daily vaginal specimens for 7 days prior to initiating T and for 90 days thereafter. These specimens will be used for vaginal Gram stain, 16S rRNA gene sequencing and shotgun metagenomic sequencing to characterise shifts in the vaginal microbiota over time, including development of iBV. Participants will complete daily diaries on douching, menses and behavioural factors including sexual activity during the study.

ETHICS AND DISSEMINATION

This protocol is approved through the single Institutional Review Board mechanism by the University of Alabama at Birmingham. External relying sites are the Louisiana State University Health Sciences Center, New Orleans Human Research Protection Program and the Indiana University Human Research Protection Program. Study findings will be presented at scientific conferences and peer-reviewed journals as well as shared with community advisory boards at participating gender health clinics and community-based organisations servicing transgender people.

REGISTRATION DETAILS

Protocol # IRB-300008073.

Chlamydia trachomatis as a Current Health Problem: Challenges and Opportunities

Chlamydia is one of the most common sexually transmitted bacterial infections (STIs) worldwide. It is caused by Chlamydia trachomatis (CT), which is an obligate intracellular bacterium. In some cases, it can occur in coinfection with other parasites, increasing the pathologic potential of the infection. The treatment is based on antibiotic prescription; notwithstanding, the infection is mostly asymptomatic, which increases the risk of transmission. Therefore, some countries have implemented Chlamydia Screening Programs in order to detect undiagnosed infections. However, in Portugal, there is no CT screening plan within the National Health Service. There is no awareness in the general healthcare about the true magnitude of this issue because most of the methods used are not Nucleic Acid Amplification Technology-based and, therefore, lack sensitivity, resulting in underreporting infection cases. CT infections are also associated with possible long-term severe injuries. In detail, persistent infection triggers an inflammatory milieu and can be related to severe sequels, such as infertility. This infection could also trigger gynecologic tumors in women, evidencing the urgent need for cost-effective screening programs worldwide in order to detect and treat these individuals adequately. In this review, we have focused on the success of an implemented screening program that has been reported in the literature, the efforts made concerning the vaccine discovery, and what is known regarding CT infection. This review supports the need for further fundamental studies in this area in order to eradicate this infection and we also suggest the implementation of a Chlamydia Screening Program in Portugal.

Multicenter comparison of nucleic acid amplification tests for the diagnosis of rectal and oropharyngeal Chlamydia trachomatis and Neisseria gonorrhoeae infection

Research using nucleic acid amplification tests (NAATs) have repeatedly found rectal and oropharyngeal infections with Chlamydia trachomatis and Neisseria gonorrhoeae to be common and potentially more difficult to treat than genital infections. Unfortunately, public health and patient care efforts have been hampered by the lack of FDA-cleared NAATs with claims for anorectal or oropharyngeal samples. At the time of the initiation of this study, no commercially available assays had these claims. We formed a novel partnership among academic institutions and diagnostic manufacturers to address this public health need. From May 2018 through August 2019 we recruited 1108 women, 1256 men and 26 transgender persons each of whom provided 3 anal and 3 oropharyngeal swab specimens. The 3 anal swabs were pooled into a single transport tube as were the 3 oropharyngeal swabs. The performance of each of three study assays was estimated by comparison to the composite result and relative to one another. Percent positivity for chlamydia was 5.9 and 1.2% from anal and oropharyngeal specimens, respectively compared to 4.2 and 4.1% for gonorrhea. Sensitivity for chlamydia detection ranged from 81.0-95.1% and 82.8-100% for anal and oropharyngeal specimens, respectively. Gonorrhea sensitivity ranged from 85.9-99.0% and 74.0-100% for anal and oropharyngeal samples, respectively. Specificity estimates were ≥ 98.9% for all assays, organisms and sample types. Although there was heterogeneity between sensitivity estimates, these assays offer better ability to detect extra genital infections than culture and potential solutions for providing appropriate sexual healthcare for populations in which these infections are of concern.

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.

Trichomonas vaginalis detection in urogenital specimens from symptomatic and asymptomatic men and women using the cobas TV/MG test

Trichomonas vaginalis is a prevalent sexually transmitted infection (STI). Diagnosis has historically relied on either microscopic analysis or culture, the latter being the previous gold standard. However, these tests are not readily available for male diagnosis, generally only perform well for symptomatic women, and are not as sensitive as nucleic acid amplification tests (NAATs). Men are largely asymptomatic but carry the organism and transmit to their sexual partners. This multicenter, prospective study evaluated the performance of the cobas T. vaginalis/Mycoplasma genitalium (TV/MG) assay for detection of T. vaginalis DNA compared with patient infection status (PIS) defined by a combination of commercially available NAATs and culture using urogenital specimens. A total of 2,064 subjects (984 men and 1,080 women, 940 [45.5%] symptomatic, 1,124 [54.5%] asymptomatic) were evaluable. In women, sensitivity ranged from 99.4% (95% confidence interval [CI] 96.8 to 99.9%) using vaginal samples to 94.7% (95% CI 90.2 to 97.2%) in PreservCyt samples. Specificity ranged from 98.9 to 96.8% (95% CI 95.4 to 97.8%). In men, the cobas TV/MG assay was 100% sensitive for the detection of T. vaginalis in both male urine samples and meatal swabs, with specificity of 98.4% in urine samples and 92.5% in meatal swabs. The cobas TV/MG is a suitable diagnostic test for the detection of T. vaginalis, which could support public health efforts toward infection control and complement existing STI programs.

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.

Evaluation of a quantitative RT-PCR assay for the detection of the emerging coronavirus SARS-CoV-2 using a high throughput system

Facing the emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), high-volume respiratory testing is demanded in laboratories worldwide. We evaluated the performance of a molecular assay for the detection of SARS-CoV-2 on a high-throughput platform, the cobas 6800, using the 'open channel' for integration of a laboratory-developed assay. We observed good analytical performance in clinical specimens. The fully automated workflow enables high-throughput testing with minimal hands-on time, while offering fast and reliable results.

A profile of the cobas® CT/NG assay on the cobas® 6800/8800 system for detection of Chlamydia trachomatis and Neisseria gonorrhoeae

Introduction: Chlamydia trachomatis and Neisseria gonorrhoeae infection rates continue to rise worldwide. Increasing screening of the largely asymptomatic infections is critical for timely and effective disease control. Laboratory solutions that can handle increasing volumes and generate highly accurate test results are needed in reference labs that provide the majority of chlamydia/gonorrhea testing.Areas covered: This review will describe the Roche cobas CT/NG assay performed on the cobas 6800/8800 system. The instrument features will be described as will the performance of the assay.Expert opinion: The high throughput cobas 6800/8800 can be integrated with clinical chemistry, hematology and immunology systems which will increase reference lab efficiency. The broad menu, ease of expansion with lab developed tests, in combination with features that support lab efficiencies and cost management while assuring high sensitivity and specificity, make this a uniquely effective diagnostic tool.

Clinical evaluation of multiplex RT-PCR assays for the detection of influenza A/B and respiratory syncytial virus using a high throughput system

BACKGROUND

Lower respiratory tract infections are a major threat to public health systems worldwide, with RSV and influenza being the main agents causing hospitalization. In outbreak situations, high-volume respiratory testing is needed. In this study, we evaluated the analytical and clinical performance of a pre-designed primer/probe set for the simultaneous multiplex detection of both viruses on a high-throughput platform, the cobas^® 6800, using the "open channel" of the system for integration of lab-developed assays for the detection of influenza and RSV.

RESULTS

Using the influenza/RSV qPCR Assay with swabs, LoD (95%) in TCID50/mL for influenza-A was 0.009, influenza-B 0.003, RSV-A 0.202, and RSV-B 0.009. Inter-run variability (3xLoD) was low (<1 Ct for all targets). Of 371 clinical respiratory specimens analyzed, results were concordant for 358 samples. The calculated sensitivity and specificity of the assay were 98.3% and 98.4% for Flu-A, 100% and 98.5% for Flu-B, and 98.6% and 99.7% for RSV. All quality assessment panel specimens (N = 63, including avian influenza strains) were correctly identified. None of the tested microorganisms showed cross-reactivity.

CONCLUSION

Compared with CE-IVD assays, the assay evaluated here showed good analytical and clinical sensitivity and specificity with broad coverage of different virus strains. It offers high-throughput capacity with low hands-on time, facilitating the laboratory management of large respiratory outbreaks.