Performance of the Abbott RealTime CT/NG for detection of Chlamydia trachomatis and Neisseria gonorrhoeae

TransOdara study: the challenge of integrating methods, settings and procedures during the COVID-19 pandemic in Brazil

OBJECTIVE

Sexually transmitted infections (STIs) disproportionately affect transgender women and travestis (TGW), who often lack access to healthcare due to stigma and discrimination. We describe the approach and methodology of a study investigating the prevalence of syphilis, HIV, hepatitis A, B, and C, Neisseria gonorrhoeae (NG), Chlamydia trachomatis (CT), and human papillomavirus (HPV) among TGW, as well as their knowledge and perceptions regarding syphilis, to better inform policies to curb STIs among this vulnerable population.

METHODS

TransOdara was a multicentric, cross-sectional study conducted among TGW in five capital cities from major Brazilian regions between December 2019 and July 2021. Self-identified transgender women and travestis aged >18 years were recruited using respondent-driven sampling after a qualitative formative phase, completed an interviewer-led questionnaire, were offered a physical examination, and were also asked to provide samples from multiple sites to detect various STIs, starting vaccination and treatment when indicated.

RESULTS

A total of 1,317 participants were recruited from the five study locations: Campo Grande (n=181, 13.7%), Manaus (n=340, 25.8%), Porto Alegre (n=192, 14.6%), Salvador (n=201, 15.3%), and São Paulo (n=403, 30.6%). The recruitment period varied at each study location due to logistic constraints imposed by the COVID-19 pandemic.

CONCLUSION

Despite the enormous challenges posed by the co-occurrence of the COVID-19 pandemic and field work targeting a vulnerable, elusive, and scattered population, the TransOdara project has been effectively implemented. Caveats did not preclude 1,300 TGW from being interviewed and tested, amid a significant epidemic that disrupted health services and research projects in Brazil and worldwide.

Anorectal gonorrhoea and chlamydia among transgender women in Brazil: prevalence and assessment of performance and cost of anorectal infection detection and management approaches

OBJECTIVES

We aimed to determine the prevalence of anorectal Neisseria gonorrhoeae (NG) and Chlamydia trachomatis (CT) among transgender women in Brazil, and to assess the performance and costs of various approaches for the diagnosis and management of anorectal NG/CT.

METHODS

TransOdara was a multicentric, cross-sectional STI prevalence study among 1317 transgender women conducted in five capital cities representing all Brazilian regions. Participants aged >18 years were recruited using respondent-driven sampling (RDS), completed an interviewer-led questionnaire, offered an optional physical examination and given choice between self-collected or provider-collected samples for NG/CT testing. Performance and cost indicators of predetermined management algorithms based on the WHO recommendations for anorectal symptoms were calculated.

RESULTS

Screening uptake was high (94.3%) and the estimated prevalence of anorectal NG, CT and NG and/or CT was 9.1%, 8.9% and 15.2%, respectively. Most detected anorectal NG/CT infections were asymptomatic (NG: 87.6%, CT: 88.9%), with a limited number of participants reporting any anorectal symptoms (9.1%). Of those who permitted anal examination, few had clinical signs of infection (13.6%). Sensitivity of the tested algorithms ranged from 1.4% to 5.1% (highest for treatment based on the reported anorectal discharge or ulcer and receptive anal intercourse (RAI) in the past 6 months) and specificity from 98.0% to 99.3% (highest for treatment based on the reported anorectal discharge with clinical confirmation or report of RAI). The estimated cost-per-true case of anorectal NG/CT infection treated varied from lowest providing treatment for anorectal discharge syndrome based on the reported RAI ($2.70-4.28), with algorithms including clinical examinations decreasing cost-effectiveness.

CONCLUSIONS

High prevalence of mostly asymptomatic anorectal NG and CT was observed among Brazilian transgender women. Multi-site NG/CT screening should be offered to transgender women. Where diagnostic testing capacity is limited, syndromic management for those presenting with anorectal symptoms is recommended.

HIV Prevention and Care Among Black Cisgender Sexual Minority Men and Transgender Women: Protocol for an HIV Status-Neutral Cohort Study Using an Observational-Implementation Hybrid Approach

BACKGROUND

Black cisgender gay, bisexual, and other sexual minority men (SMM) and transgender women (TW) continue to be heavily affected by HIV. Further research is needed to better understand HIV prevention and care outcomes in this population. In particular, there is a need for research examining the impact of substance use and sleep health on HIV prevention and treatment outcomes among Black SMM and TW.

OBJECTIVE

This paper outlines the study methods being used in the recently launched follow-up study to the Neighborhoods and Networks (N2) study, which we refer to as N2 Part 2 (N2P2). N2P2 aims to address this gap in the literature, build off the findings of the original N2 study, and identify socioenvironmental determinants of health, including whether neighborhood and network factors mediate and moderate these relationships.

METHODS

Building on the N2 cohort study in Chicago from 2018 to 2022, N2P2 used a prospective longitudinal cohort design and an observational-implementation hybrid approach. With sustained high levels of community engagement, we aim to recruit a new sample of 600 Black SMM and TW participants residing in the Chicago metropolitan statistical area. Participants are asked to participate in 3 study visits across an 18-month study period (1 visit every 9 months). Four different forms of data are collected per wave: (1) an in-person survey, (2) biological specimen collection, (3) a daily remote ecological momentary assessment for 14 days after each study visit, and (4) data from electronic health records. These forms of data collection continue to assess neighborhood and network factors and specifically explore substance use, sleep, immune function, obesity, and the implementation of potential interventions that address relevant constructs (eg, alcohol use and pre-exposure prophylaxis adherence).

RESULTS

The N2P2 study was funded in August 2021 by the National Institute of Drug Abuse (R01DA054553 and R21DA053156) and National Heart, Lung, and Blood Institute (R01HL160325). This study was launched in November 2022. Recruitment and enrollment for the first wave of data collection are currently ongoing.

CONCLUSIONS

The N2P2 study is applying innovative methods to comprehensively explore the impacts of substance use and sleep health on HIV-related outcomes among an HIV status-neutral cohort of Black SMM and TW in Chicago. This study is applying an observational-implementation hybrid design to help us achieve findings that support rapid translation, a critical priority among populations such as Black SMM and TW that experience long-standing inequities with regard to HIV and other health-related outcomes. N2P2 will directly build off the findings that have resulted from the original N2 study among Black SMM and TW in Chicago. These findings provide a better understanding of multilevel (eg, individual, network, and neighborhood) factors that contribute to HIV-related outcomes and viral suppression among Black SMM and TW.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/48548.

Integrated microscale immiscible phase extraction and isothermal amplification for colorimetric detection of Neisseria gonorrhoeae

Gonorrhea is the second most common sexually transmitted infection (STI) with around 87 million cases worldwide estimated in 2016 by the World Health Organization. With over half of the cases being asymptomatic, potential life-threatening complications and increasing numbers of drug-resistant strains, routine monitoring of prevalence and incidence of infections are key preventive measures. Whilst gold standard qPCR tests have excellent accuracy, they are neither affordable nor accessible in low-resource settings. In this study, we developed a lab-on-a-chip platform based on microscale immiscible filtration to extract, concentrate and purify Neisseria gonorrhoeae DNA with an integrated detection assay based on colorimetric isothermal amplification. The platform was capable of detecting as low as 500 copies/mL from spiked synthetic urine and showed no cross-reactivity when challenged with DNAs from other common STIs. The credit card-size device allows DNA extraction and purification without power or centrifuges, and the detection reaction only needs a low-tech block heater, providing a straightforward and visual positive/negative result within 1 h. These advantages offer great potential for accurate, affordable and accessible monitoring of gonorrhea infection in resource-poor settings.

Perceptions and Experiences of Returning Self-collected Specimens for HIV, Bacterial STI and Potential PrEP Adherence Testing among Sexual Minority Men in the United States

Few studies among gay, bisexual and other men who have sex with men (GBMSM) have examined facilitators and barriers to self-collecting specimens for extragenital STI screening, and none have evaluated attitudes towards self-collecting hair samples that can be utilized for PrEP drug level testing to assess adherence. To address this gap, we interviewed 25 sexually active GBMSM who were offered a choice to self-collect and return finger-stick blood samples (for actual HIV testing), pharyngeal swabs, rectal swabs and urine specimens (for actual gonorrhea and chlamydia testing), and hair samples (to visually determine their adequacy for PrEP drug level testing): 11 who returned all, 4 who returned some, and 10 who did not return any. Participants found self-collecting finger-stick blood samples and rectal swabs more challenging than other specimens. Frequently discussed facilitators of return included an opportunity to confirm one's HIV or STI status, limited access to a healthcare provider and a desire to advance research focusing on home-based testing. Commonly cited barriers to return included low self-efficacy pertaining to self-collection and apprehension around the possibility of delay or loss of specimens during transit. Offering additional support such as real-time video conferencing may prove helpful in future field-based research with GBMSM.

Prevalence of Chlamydia trachomatis, Neisseria gonorrhoeae, and Mycoplasma genitalium among Patients with Urogenital Symptoms in Istanbul

Chlamydia trachomatis, Neisseria gonorrhoeae, and Mycoplasma genitalium are the three most commonly reported sexually transmitted bacteria. The present study aimed to investigate the presence of C. trachomatis, N. gonorrhoeae, and M. genitalium in urogenital samples collected from 18-68-year-old Turkish patients who were admitted to the hospital with various urogenital symptoms. A total of 360 patients with symptoms of STD were included in the study. Following DNA extraction by QIAamp Mini Kit, the presence of C. trachomatis, N. gonorrhoeae, and M. genitalium were investigated using multiplex real-time PCR. Causative organisms were identified in 68 (18.9%) of 360 patients. C. trachomatis, N. gonorrhoeae, and M. genitalium were detected in 40 (11.1%), 14 (3.9%), and 28 (7.8%) of the patients, respectively. Patients 21-30 years of age represented more than one-third (37.8%) of positive patients. Of all patients, dual infections of C. trachomatis-M. genitalium, N. gonorrhoeae-C. trachomatis, N. gonorrhoeae-M. genitalium, and triple infection of C. trachomatis-N. gonorrhoeae-M. genitalium were determined in 1.6% (6/360), 1.3% (5/360), 0.2% (1/360), and 0.2% (1/360) of the patients, respectively. In CT-, NG-, and MG-positive patients, different STI agents were also found such as HIV, HBV, HPV, HSV2, T. pallidum, and T. vaginalis. In conclusion, among C. trachomatis, N. gonorrhoeae, and M. genitalium, CT was the most frequently detected bacterial cause of STDs in our hospital at Istanbul. Co-infections, which comprise more than one-fifth of the cases, should not be underestimated. Regular screening and following up of STD agents using multiplex real-time PCR-based diagnostic methods enabling the immediate detection of co-infections are essential for the treatment and primary prevention of STDs.

Simultaneous real-time PCR detection of nine prevalent sexually transmitted infections using a predesigned double-quenched TaqMan probe panel

Sexually transmitted diseases are major causes of infertility, ectopic pregnancy, and premature birth. Here, we developed a new multiplex real-time polymerase chain reaction (PCR) assay for the simultaneous detection of nine major sexually transmitted infections (STIs) found in Vietnamese women, including Chlamydia trachomatis, Neisseria gonorrhoeae, Gardnerella vaginalis, Trichomonas vaginalis, Candida albicans, Mycoplasma hominis, Mycoplasma genitalium, and human alphaherpesviruses 1 and 2. A panel containing three tubes × three pathogens/tube was predesigned based on double-quenched TaqMan probes to increase detection sensitivity. There was no cross-reactivity among the nine STIs and other non-targeted microorganisms. Depending on each pathogen, the agreement with commercial kits, sensitivity, specificity, repeatability and reproducibility coefficient of variation (CV), and limit of detection of the developed real-time PCR assay were 99.0%-100%, 92.9%-100%, 100%, <3%, and 8-58 copies/reaction, respectively. One assay cost only 2.34 USD. Application of the assay for the detection of the nine STIs in 535 vaginal swab samples collected from women in Vietnam yielded 532 positive cases (99.44%). Among the positive samples, 37.76% had one pathogen, with G. vaginalis (33.83%) as the most prevalent; 46.36% had two pathogens, with G. vaginalis + C. albicans as the most prevalent combination (38.13%); and 11.78%, 2.99%, and 0.56% had three, four, and five pathogens, respectively. In conclusion, the developed assay represents a sensitive and cost-effective molecular diagnostic tool for the detection of major STIs in Vietnam and is a model for the development of panel detections of common STIs in other countries.

Study Evaluating Self-Collected Specimen Return for HIV, Bacterial STI, and Potential Pre-Exposure Prophylaxis Adherence Testing Among Sexual Minority Men in the United States

Web-based HIV and sexually transmitted infection (STI) prevention studies are increasingly requesting gay, bisexual, and other men who have sex with men (GBMSM) to return self-collected specimens for laboratory processing. Some studies have solicited self-collected extragenital swabs for gonorrhea and chlamydia testing, but to date, none have solicited self-collected hair samples for pre-exposure prophylaxis (PrEP) adherence testing. Project Caboodle! offered 100 racially/ethnically diverse GBMSM aged 18 to 34 years residing across the United States a choice to self-collect at home and return by mail any of the following: a finger-stick blood sample (for HIV testing), a pharyngeal swab, a rectal swab and a urine specimen (for gonorrhea and chlamydia testing), and a hair sample (to visually assess its adequacy for PrEP drug level testing). Despite not incentivizing specimen return, 51% mailed back at least one type of specimen within 6 weeks (1% returned three specimens, 11% returned four specimens and 39% returned all five specimens). The majority of returned specimens were adequate for laboratory processing. Significantly more participants without a college education (p = .0003) and those who were working full-time or part-time (p = .0070) did not return any specimens. In addition, lower levels of HIV-related knowledge (p = .0390), STI-related knowledge (p = .0162), concern about contracting HIV (p = .0484), and concern about contracting STIs (p = .0108) were observed among participants who did not return any specimens. Self-collection of specimens holds promise as a remote monitoring strategy that could supplement testing in clinical settings, but a better understanding of why some GBMSM may choose to fully, partially, or not engage in this approach is warranted.

Diagnosis and treatment of gonorrhoea: 2019 Belgian National guideline for primary care

OBJECTIVES

Gonorrhoea continues to be a public health concern in Belgium with pharyngeal and rectal infections increasing in persons with high-risk sexual behaviour. Belgian health care practitioners rely on international guidance when managing gonorrhoea resulting in non-adapted suboptimal care for the Belgian patient. This guideline will rectify this situation.

METHODS

This guideline was developed following an evidence-based approach and involving a guideline development group (GDG). Research questions were prioritised by the GDG and researchers conducted a systematic review of the evidence that was assessed using GRADE approach.

RESULTS

The guideline offers recommendations for gonorrhoea diagnosis, treatment and management for primary care professionals in Belgium and applies a risk group approach. This approach aims for improved identification of at-risk persons and targeted testing of at-risk groups; it includes behavioural questioning when deciding on diagnostic sampling and provides clear advice on treatment. The guideline defines when to add surveillance testing for antibiotic resistance, and what consists of good follow-up.

RESULTS

A concerted application of this guideline by all stakeholders in Belgium may result in improving the diagnosis of infections and eventually addressing the emerging multi-drug resistance.

Detection of Neisseria gonorrhoeae or Chlamydia trachomatis from oral wash specimens using the Abbott RealTime CT/NG assay and the Cobas 4800 CT/NG assay: A prospective study

INTRODUCTION

Isolating oropharyngeal Neisseria gonorrhoeae (NG) and Chlamydia trachomatis (CT) from oral wash specimens (OWSs) is uncommon. Therefore, we evaluated the performance of the Abbott RealTime CT/NG assay and the Cobas 4800 CT/NG assay in detecting NG and CT in OWSs.

METHODS

This multicenter prospective study included 457 patients from 14 medical facilities suspected of having untreated male urethritis or female cervicitis from November 2014 to December 2015. OWSs were collected and tested using the Abbott and Cobas assays. Finally, the discordant results were confirmed using the APTIMA Combo 2 transcription-mediated amplification assay and retested using each assay.

RESULTS

The sensitivity and specificity of the Abbott assay were 100% and 97.2% for NG and 87.5% and 100% for CT, respectively, and of the Cobas assay were 100% and 98.8% for NG and 93.8% and 99.8% for CT, respectively. Both assays had high negative but low positive predictive values for oropharyngeal NG (Abbott assay: 65.7%, Cobas assay: 82.1%). Based on the definition of "true positive," the prevalence of oropharyngeal NG and CT were 5.0% and 3.5%, respectively.

CONCLUSIONS

The Abbott and Cobas assays using OWSs had high sensitivity and specificity, which can help diagnose oropharyngeal NG and CT. We consider that if a positive result is obtained, the patient should be treated because the negative predictive values were high. However, limited data are available on oropharyngeal NG and CT detection, and further studies are needed to clarify the role of oropharyngeal sexually transmitted infections.

AAUS guideline for chlamydial urethritis

Urogenital chlamydial infection is the most common sexually transmitted infection. Many cases of chlamydial infection are reported worldwide every year. Genital chlamydial infection in women can also cause obstetric issues, including infertility and miscarriage. For that purpose, appropriate care should be conducted with the latest knowledge. Only few guidelines come from Asian countries. The Asian Association of Urinary Tract Infection and Sexually Transmitted Infection (AAUS) belonging to the Urological Association of Asia (UAA) had developed the guidelines regarding chlamydial urethritis. We have collected the feedback and updated the guidelines which is now submitted for consideration of publication. In addition to the levels of evidence, the recommendation grades were defined using the modified GRADE methodology. Herein, we present the new edition of the UAA-AAUS guidelines for chlamydial urethritis.

Acceptability and Feasibility of a Telehealth Intervention for STI Testing Among Male Couples

Partnered gay, bisexual and other men who have sex with men (GBMSM) are less likely to engage in HIV and STI testing. We enrolled 51 male couples from a larger study of home HIV testing to test the feasibility of a dyadic home STI testing intervention delivered via telehealth, consisting of two telehealth sessions delivered via video-chat. In the first session, an interventionist demonstrated the specimen collection kits. In the second session, an interventionist delivered the STI results. Participants reported very high levels of acceptability of the intervention: 92% reported the telehealth calls quality as very good, 99% reported the sample collection instructions were clear, and 96% of respondents returned specimens for collection. 9% of participants tested positive for chlamydia or gonorrhea, and all were linked to care. The intervention has the potential to surmount economic, physical and stigma-related barriers to attending clinics for STI testing, but these results need to be further tested in more diverse samples of male couples.

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.

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.

A portable magnetofluidic platform for detecting sexually transmitted infections and antimicrobial susceptibility

Effective treatment of sexually transmitted infections (STIs) is limited by diagnostics that cannot deliver results rapidly while the patient is still in the clinic. The gold standard methods for identification of STIs are nucleic acid amplification tests (NAATs), which are too expensive for widespread use and have lengthy turnaround times. To address the need for fast and affordable diagnostics, we have developed a portable, rapid, on-cartridge magnetofluidic purification and testing (PROMPT) polymerase chain reaction (PCR) test. We show that it can detect Neisseria gonorrhoeae, the pathogen causing gonorrhea, with simultaneous genotyping of the pathogen for resistance to the antimicrobial drug ciprofloxacin in <15 min. The duplex test was integrated into a low-cost thermoplastic cartridge with automated processing of penile swab samples from patients using magnetic beads. A compact instrument conducted DNA extraction, PCR, and analysis of results while relaying data to the user via a smartphone app. This platform was tested on penile swab samples from sexual health clinics in Baltimore, MD, USA (n = 66) and Kampala, Uganda (n = 151) with an overall sensitivity and specificity of 97.7% (95% CI, 94.7 to 100%) and 97.6% (95% CI, 94.1 to 100%), respectively, for N. gonorrhoeae detection and 100% concordance with culture results for ciprofloxacin resistance. This study paves the way for delivering accessible PCR diagnostics for rapidly detecting STIs at the point of care, helping to guide treatment decisions and combat the rise of antimicrobial resistant pathogens.

Array testing for multiplex assays

Group testing involves pooling individual specimens (e.g., blood, urine, swabs, etc.) and testing the pools for the presence of disease. When the proportion of diseased individuals is small, group testing can greatly reduce the number of tests needed to screen a population. Statistical research in group testing has traditionally focused on applications for a single disease. However, blood service organizations and large-scale disease surveillance programs are increasingly moving towards the use of multiplex assays, which measure multiple disease biomarkers at once. Tebbs and others (2013, Two-stage hierarchical group testing for multiple infections with application to the Infertility Prevention Project. Biometrics69, 1064-1073) and Hou and others (2017, Hierarchical group testing for multiple infections. Biometrics73, 656-665) were the first to examine hierarchical group testing case identification procedures for multiple diseases. In this article, we propose new non-hierarchical procedures which utilize two-dimensional arrays. We derive closed-form expressions for the expected number of tests per individual and classification accuracy probabilities and show that array testing can be more efficient than hierarchical procedures when screening individuals for multiple diseases at once. We illustrate the potential of using array testing in the detection of chlamydia and gonorrhea for a statewide screening program in Iowa. Finally, we describe an R/Shiny application that will help practitioners identify the best multiple-disease case identification algorithm.

Prevalence and Factors Associated With HIV and Sexually Transmitted Infections Among Female Sex Workers in Bamako, Mali

BACKGROUND

We aimed to (1) estimate the prevalence of HIV and other sexually transmitted infections (STIs) among female sex workers (FSWs) in Bamako, Mali, and (2) identify factors associated with STIs including HIV infection in this population.

METHODS

We analyzed baseline data from a prospective observational cohort study on cervical cancer screening, human papillomavirus, and HIV infections among FSWs 18 years or older recruited in Bamako. Multivariable log-binomial regression was used to estimate the adjusted prevalence ratios (APRs) with 95% confidence interval (95% CI) for HIV infection and STIs versus associated factors.

RESULTS

Among 353 women participating in the study, mean age was 26.8 (±7.6) years. HIV prevalence was 20.4%, whereas 35.1% of the FSWs had at least one STI. Factors significantly associated with HIV were older age (P < 0.0001, test for trend), duration of sex work ≥6 years (APR, 1.92; 95% CI, 1.22-3.02), uneducated status (APR, 2.24; 95% CI, 1.16-4.34), less than 10 clients in the last 7 days (APR, 1.55; 95% CI, 1.02-2.34), and gonococcal (APR, 1.85; 95% CI, 1.21-2.82) and chlamydial (APR, 2.58; 95% CI, 1.44-4.62) infections. Younger age (P = 0.018, test for trend), having ≥10 clients in the last week (APR, 1.47; 95% CI, 1.11-1.94), and HIV infection (APR, 2.00; 95% CI, 1.49-2.69) were significantly associated with STIs.

CONCLUSIONS

HIV and curable STI prevalence are high among FSWs in Bamako. There is thus a need to enhance the efficiency of interventions toward FSWs in Mali to reduce the burden of HIV and STIs among them and prevent HIV spread to the general population.

Understanding disparities in viral suppression among Black MSM living with HIV in Atlanta Georgia

INTRODUCTION

Due to factors associated with structural racism, Black men who have sex with men (MSM) living with HIV are less likely to be virally suppressed compared to white MSM. Most of these data come from clinical cohorts and modifiable reasons for these racial disparities need to be defined in order to intervene on these inequities. Therefore, we examined factors associated with racial disparities in baseline viral suppression in a community-based cohort of Black and white MSM living with HIV in Atlanta, GA.

METHODS

We conducted an observational cohort of Black and white MSM living with HIV infection in Atlanta. Enrolment occurred from June 2016 to June 2017 and men were followed for 24 months; laboratory and behavioural survey data were collected at 12 and 24 months after enrolment. Explanatory factors for racial disparities in viral suppression included sociodemographics and psychosocial variables. Poisson regression models with robust error variance were used to estimate prevalence ratios (PR) for Black/white differences in viral suppression. Factors that diminished the PR for race by ≥5% were considered to meaningfully attenuate the racial disparity and were included in a multivariable model.

RESULTS

Overall, 26% (104/398) of participants were not virally suppressed at baseline. Lack of viral suppression was significantly more prevalent among Black MSM (33%; 69/206) than white MSM (19%; 36/192) (crude Prevalence Ratio (PR) = 1.6; 95% CI: 1.1 to 2.5). The age-adjusted Black/white PR was diminished by controlling for: ART coverage (12% decrease), housing stability (7%), higher income (6%) and marijuana use (6%). In a multivariable model, these factors cumulatively mitigated the PR for race by 21% (adjusted PR = 1.1 [95% CI: 0.8 to 1.6]).

CONCLUSIONS

Relative to white MSM, Black MSM living with HIV in Atlanta were less likely to be virally suppressed. This disparity was explained by several factors, many of which should be targeted for structural, policy and individual-level interventions to reduce racial disparities.

Prevalence and predictors of asymptomatic Chlamydia trachomatis and Neisseria gonorrhoeae in a Ugandan population most at risk of HIV transmission

The aim of this study was to establish the prevalence of asymptomatic Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) in key populations at increased risk of transmission of HIV. Additionally, we aimed to identify the associated risk factors for asymptomatic sexually transmitted infections (STIs) and evaluate the acceptability of self-collected samples. Asymptomatic people living with HIV (PLHIV) in the following categories were offered testing: discordant couples, young adults, pregnant patients and those attending the 'most-at-risk-population' clinic. Patients provided first-pass urine, self-collected vaginal swabs or both to test for NG and CT by polymerase chain reaction using BD ProbeTec™. Patients also completed an acceptability questionnaire, including the negative partner of an HIV-positive participant. Three hundred and sixty-three PLHIV had an STI screen. Asymptomatic STIs were only diagnosed in women (prevalence 5.7%), overall prevalence 3.9% (n = 14). Factors independently associated with an STI in women were being under 25 years (OR 9.63 95% CI 1.56-59.5) and having more than one sexual partner (OR 8.06 95% CI 1.07-60.6). Four hundred and seven completed the acceptability questionnaire. More than 95% of patients found self-sampling easy and comfortable and 83.8% would believe the results. Women significantly preferred the option of self-sampling, 56.9% versus 29.3% of men (p < 0.001). Acceptability of self-sampling was high. Young women with or at risk of HIV are an important target for STI testing regardless of symptoms. There is need for diagnostic tests that are inexpensive, rapid and accurate especially in resource-limited settings.

Clinical Performance of the BD CTGCTV2 Assay for the BD MAX System for Detection of Chlamydia trachomatis, Neisseria gonorrhoeae, and Trichomonas vaginalis Infections

BACKGROUND

Diagnostic options to combat the increasing rates of sexually transmitted infections recorded throughout the world increasingly include multiplex assays. Here we describe the estimated sensitivity and specificity of a triplex molecular assay that simultaneously detects Chlamydia trachomatis (CT), Neisseria gonorrhoeae (or gonococci [GC]), and Trichomonas vaginalis (TV).

METHODS

Participants (2547 women and 1159 men) were recruited from 12 clinics in the United States. BD CTGCTV2 for BD MAX System assay (CTGCTV2) results were obtained from vaginal and endocervical swabs, endocervical samples in cytology medium, and female and male urine. Results were compared with infection standards that were sample type and pathogen dependent.

RESULTS

Female specimen sensitivity estimates ranged from 92.7% to 98.4%, 92.9% to 100%, and 86.6% to 100% for CT, GC and TV, respectively. Male urine sensitivity estimates were 96.7%, 99.2%, and 97.9% for CT, GC, and TV, respectively. Specificity estimates were >98.7% for all sample types.

CONCLUSIONS

BD CTGCTV2 performed well using a variety of sample types. As a true triplex assay, performed using a benchtop instrument, BD CTGCTV2 may be useful in settings where no testing is currently performed and in settings, such as reference laboratories, where testing turnaround time may be several days. Use of this assay at local laboratories may result in greater access to testing and a shorter time to result, which are important steps for improving our ability to combat sexually transmitted infections.

Optimizing Strategies for Chlamydia trachomatis and Neisseria gonorrhoeae Screening in Men Who Have Sex With Men: A Modeling Study

BACKGROUND

International guidelines recommend the systematic screening for Neisseria gonorrhoeae (NG) and Chlamydia trachomatis (CT) infections in all men who have sex with men (MSM) who have engaged in unprotected sex. However, the optimal screening strategy remains unclear. We developed a modeling approach to optimize NG/CT screening strategy in MSM.

METHODS

A compartmental model of NG/CT screening and infection was implemented. NG/CT anal, pharyngeal, and urine (APU) samples from MSM attending the sexually transmitted infections clinic were used to estimate the screening rate, prevalence, and incidence in a base case scenario. Different screening strategies (scenarios; S) were then evaluated: APU samples every 12 months (S1); APU samples every 3 months (S2); APU samples every 6 months (S3); anal and pharyngeal (AP) samples every 6 months (S4); and AP samples every 3 months (S5).

RESULTS

We analyzed 2973 triplet APU samples from 1255 patients. We observed 485 NG and 379 CT diagnoses. NG/CT prevalence and incidence estimates were 12.0/11.1% and 40/29 per 100 person-years, respectively, in the base case scenario. As compared to S2, the reference strategy, the proportions of missed NG/CT diagnoses were 42.0/41.2% with S1, 21.8/22.5% with S3, 25.6/28.3% with S4, and 6.3/10.5% with S5, respectively. As compared to S2, S1 reduced the cost of the analysis by 74%, S3 by 50%, S4 by 66%, and S5 by 33%. The numbers needed to screen for catching up the missed NG/CT diagnoses were 49/67 with S1, 62/82 with S3, 71/87 with S4, and 143/118 with S5.

CONCLUSIONS

S5 appears to be the best strategy, missing only 6.3/10.5% of NG/CT diagnoses, for a cost reduction of 33%.

Prevalence of new variants of Chlamydia trachomatis escaping detection by the Aptima Combo 2 assay, England, June to August 2019

We identified two new Chlamydia trachomatis (CT) variants escaping Aptima Combo 2 (AC2) assay detection, in clinical specimens of two patients. One had a C1514T mutation the other a G1523A mutation, both within the AC2 23S rRNA target region. The prevalence of such variants among persons tested for CT in England was estimated to be fewer than 0.003%.

MYCO WELL D-ONE detection of Ureaplasma spp. and Mycoplasma hominis in sexual health patients in Wales

The genital mycoplasmas are a unique group of inherently antibiotic-resistant sexually transmitted bacteria, often associated with non-gonococcal urethritis and bacterial vaginosis. The MYCO WELL D-ONE is a culture-based assay that aims to detect these organisms whilst concurrently screening them for antibiotic resistance. Urine and/or swabs from 856 informed and consented participants attending Welsh sexual health clinics were subjected to MYCO WELL D-ONE analysis, alongside qPCR and culture titration methodologies to determine sensitivity, specificity, PPV, NPV and accuracy. Resistance was confirmed by CLSI-compliant susceptibility testing and genetic mechanisms determined. The MYCO WELL D-ONE displayed a sensitivity and specificity of 91.98% and 96.44% for the detection of Ureaplasma spp., with sensitivity and specificity values of 78.23% and 98.84% for Mycoplasma hominis, compared with qPCR. Swabs harboured significantly greater bacterial loads than urine samples for both Ureaplasma spp. and M. hominis. Levofloxacin resistance rates, mediated by Ser83Leu mutation in ParC, for Ureaplasma spp. were 0.54%. Tetracycline resistance rates, mediated by tet(M), were 0.54% and 2% for Ureaplasma spp. and M. hominis, respectively; sequence analysis of tet(M)-positive Ureaplasma spp. and M. hominis strains isolated from a single individual confirmed separate resistance gene origins. The MYCO WELL D-ONE is a sensitive and specific assay for the detection of Ureaplasma spp. and M. hominis in genitourinary medicine samples, facilitating the accurate detection of these organisms within low-technology environments. While good for antibiotic resistance screening, accurate confirmation by MIC determination or molecular methods are required, and more optimally performed on urine samples.

Precision of the Abbott RealTime Assay in the Detection of Ocular Chlamydia trachomatis in a Trachoma-Endemic Area of Ethiopia

Nucleic acid amplification tests are increasingly used to detect ocular chlamydia infection in trachoma research and programs. To evaluate the reliability of Chlamydia trachomatis detection by the Abbott RealTime CT/NG assay (Abbott Molecular, Inc., Des Plaines, IL) on the m2000 platform, three conjunctival samples were collected from each of 200 children aged 0-9 years in Ethiopia: two from the right eye and one from the left eye. Four aliquots were processed for each child: two from the first right eye sample, one from the second right eye sample, and one from the left eye sample. Sixty-nine swabs were processed in a U.S. laboratory and 131 in an Ethiopian laboratory. Intra-class correlation coefficients (ICCs) were high when comparing two aliquots from the same swab (ICC ranged from 0.96 to 0.99), two separate swabs from the right eye (0.89-0.91), and one right and one left eye swab (0.87-0.89), indicating reliable chlamydial load assessment across different samples and laboratory settings.

Ocular Chlamydia trachomatis infection and infectious load among pre-school aged children within trachoma hyperendemic districts receiving the SAFE strategy, Amhara region, Ethiopia

BACKGROUND

After approximately 5 years of SAFE (surgery, antibiotics, facial cleanliness, environmental improvement) interventions for trachoma, hyperendemic (trachomatous inflammation-follicular (TF) ≥30%) districts remained in Amhara, Ethiopia. This study's aim was to characterize the epidemiology of Chlamydia trachomatis (Ct) infection and load among pre-school aged children living under the SAFE strategy.

METHODS

Conjunctival swabs from a population-based sample of children aged 1-5 years collected between 2011 and 2015 were assayed to provide Ct infection data from 4 endemic zones (comprised of 58 districts). Ct load was determined using a calibration curve. Children were graded for TF and trachomatous inflammation-intense (TI).

RESULTS

7,441 children were swabbed in 4 zones. TF and TI prevalence were 39.9% (95% confidence Interval [CI]: 37.5%, 42.4%), and 9.2% (95% CI: 8.1%, 10.3%) respectively. Ct infection prevalence was 6.0% (95% CI: 5.0%, 7.2%). Infection was highest among children aged 2 to 4 years (6.6%-7.0%). Approximately 10% of infection occurred among children aged 1 year. Ct load decreased with age (P = 0.002), with the highest loads observed in children aged 1 year (P = 0.01) vs. aged 5 years. Participants with TF (P = 0.20) and TI (P<0.01) had loads greater than individuals without active trachoma.

CONCLUSIONS

In this hyperendemic setting, it appears that the youngest children may contribute in meaningful ways towards persistent active trachoma.

Gonorrhea Prevalence Among Young Women and Men Entering the National Job Training Program, 2000-2017

Objectives. To examine long-term gonorrhea prevalence trends from a sentinel surveillance population of young people at elevated risk for gonorrhea.Methods. We analyzed annual cross-sectional urogenital gonorrhea screening data from 191 991 women (2000-2017) and 224 348 men (2003-2017) 16 to 24 years of age entering the National Job Training Program, a US vocational training program. We estimated prevalence among women using an expectation-maximization algorithm incorporated into a logistic regression to account for increases in screening test sensitivity; log-binomial regression was used to estimate prevalence among men.Results. The adjusted gonorrhea prevalence among women followed a U-shaped curve, falling from 2.9% to 1.6% from 2000 through 2011 before rising to 2.7% in 2017. The prevalence among men declined from 1.4% to 0.8% from 2003 through 2017. In the case of both women and men, the prevalence was highest across all study years among those who were Black or American Indian/Alaska Native and those who resided in the South or Midwest.Conclusions. Trends among National Job Training Program enrollees suggest that gonorrhea prevalence is rising among young women while remaining low and steady among young men.

Rapid and accurate diagnosis of Chlamydia trachomatis in the urogenital tract by a dual-gene multiplex qPCR method

Introduction. Chlamydia trachomatis (C. trachomatis, CT) is an obligatory intracellular bacterium that causes urogenital tract infections and leads to severe reproductive consequences. Therefore, a rapid and accurate detection method with high sensitivity and specificity is an urgent requirement for the routine diagnosis of C. trachomatis infections.Aim. In this study, we aimed to develop a multiplex quantitative real-time PCR (qPCR) assay based on two target regions for accurate detection of C. trachomatis in urogenital tract infections.Methodology. Primers and probes based on the conserved regions of the cryptic plasmid and 23S rRNA gene were designed. Then, two qPCR assays were established to screen for the optimal probe and primers for each of the two target regions. Subsequently, the multiplex qPCR method was developed and optimized. For the diagnostic efficiency evaluation, 1284 urogenital specimens were tested by the newly developed multiplex qPCR method, an immunological assay and a singleplex qPCR assay widely used in hospitals.Results. The multiplex qPCR method could amplify both target regions in the range of 1.0×10²-1.0×10⁸ copies ml^-1 with a strong linear relationship, and lower limits of detection (LODs) for both targets reached 2 copies PCR^-1. For the multiplex qPCR method, the diagnostic sensitivity and specificity was 100.0 % (134/134) and 99.3 % (1142/1150), respectively. For the singleplex qPCR assay, the diagnostic sensitivity and specificity was 88.8 % (119/134) and 100.0 % (1150/1150), respectively. For the immunological assay, the diagnostic sensitivity and specificity was 47.0 % (63/134) and 100.0 % (1150/1150), respectively.Conclusion. In this study, a multiplex qPCR assay with high sensitivity and specificity for rapid (≤2.0 h) and accurate diagnosis of C. trachomatis was developed. The qPCR assay has the potential to be used as a routine diagnostic method in clinical microbiology laboratories.

Gonorrhoea

The bacterium Neisseria gonorrhoeae causes the sexually transmitted infection (STI) gonorrhoea, which has an estimated global annual incidence of 86.9 million adults. Gonorrhoea can present as urethritis in men, cervicitis or urethritis in women, and in extragenital sites (pharynx, rectum, conjunctiva and, rarely, systemically) in both sexes. Confirmation of diagnosis requires microscopy of Gram-stained samples, bacterial culture or nucleic acid amplification tests. As no gonococcal vaccine is available, prevention relies on promoting safe sexual behaviours and reducing STI-associated stigma, which hinders timely diagnosis and treatment thereby increasing transmission. Single-dose systemic therapy (usually injectable ceftriaxone plus oral azithromycin) is the recommended first-line treatment. However, a major public health concern globally is that N. gonorrhoeae is evolving high levels of antimicrobial resistance (AMR), which threatens the effectiveness of the available gonorrhoea treatments. Improved global surveillance of the emergence, evolution, fitness, and geographical and temporal spread of AMR in N. gonorrhoeae, and improved understanding of the pharmacokinetics and pharmacodynamics for current and future antimicrobials in the treatment of urogenital and extragenital gonorrhoea, are essential to inform treatment guidelines. Key priorities for gonorrhoea control include strengthening prevention, early diagnosis, and treatment of patients and their partners; decreasing stigma; expanding surveillance of AMR and treatment failures; and promoting responsible antimicrobial use and stewardship. To achieve these goals, the development of rapid and affordable point-of-care diagnostic tests that can simultaneously detect AMR, novel therapeutic antimicrobials and gonococcal vaccine(s) in particular is crucial.

Acceptability and Feasibility of a Telehealth Intervention for Sexually Transmitted Infection Testing Among Male Couples: Protocol for a Pilot Study

Background

Gay, bisexual, and other men who have sex with men (MSM) are at elevated risk for acquiring sexually transmitted infections (STIs) in the United States, especially chlamydia and gonorrhea. While research has indicated main partners over casual partners may play a central role in STI risk, the frequency of STI screening among MSM couples is particularly low. Self-sample collection for chlamydia and gonorrhea screening has been shown to be highly accurate, and at-home STI testing has been shown to be highly acceptable among diverse populations. However, there is little research exploring the feasibility and acceptability of at-home chlamydia and gonorrhea screening among MSM couples. Our pilot study aims to help evaluate the viability of this screening modality as an intervention tool for MSM couples

Objective

The objective of this study was to assess the feasibility and acceptability of an at-home chlamydia and gonorrhea sample collection and remote lab testing program among a sample of 50 MSM couples living in the United States.

Methods

This pilot study enrolled 50 MSM couples, ranging from 18-40 years old and living in the United States, who participated in a larger at-home HIV testing randomized controlled trial. Participating couples completed a pretest instructional video call and then had the option of completing at-home sample collection across three bodily sites (rectal swab, pharyngeal swab, and urine sample) for remote chlamydia and gonorrhea lab testing. For participants who completed any sample collection, they received their results via a posttest video call. All participants completed an online survey examining satisfaction and acceptability of the home testing process, experience with logistics, willingness to test at home in the future, recent sexual risk behavior, STI testing history, and linkage to care. A subset of 10 couples completed an in-depth interview about their attitudes towards the sample collection process, different decisions they made while collecting their samples, and their experience accessing treatment (for those who received a positive result).

Results

Recruitment began in September 2017, and as of March 2019 a total of 50 couples have been enrolled. Overall, 49/50 couples have returned their samples and completed the posttest delivery call, and 10 in-depth interviews have been completed and transcribed.

Conclusions

Screening MSM couples at home for chlamydia and gonorrhea and providing video-facilitated results delivery may offer a tailored approach to address the increasing prevalence of these STIs. By collecting data on how MSM couples experience at-home STI screening, this project will provide valuable insight into the utility of such a service delivery program to public health interventionists and researchers alike.

International Registered Report Identifier (IRRID)

DERR1-10.2196/14481

Simultaneous detection of eleven sexually transmitted agents using multiplexed PCR coupled with MALDI-TOF analysis

Purpose

Sexually transmitted infections (STIs), representing a major global health problem, are caused by different microbes, including bacteria, viruses, and protozoa. Unfortunately, infections of different sexually transmitted pathogens often present similar clinical symptoms, so it is almost impossible to distinguish them clinically. Therefore, the aim of the current study was to develop a sensitive, multitarget, and high-throughput method that can detect various agents responsible for STIs.

Methods

We developed and tested a 23-plex PCR coupled with matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry (MS) assay (sexually transmitted infection-mass spectrometry, STI-MS) that simultaneously targets 11 different agents, including 8 most common clinical pathogens related to STIs (HSV-1, HSV-2, Neisseria gonorrhoeae, Chlamydia trachomatis, Treponema pallidum, Trichomonas vaginalis, Mycoplasma genitalium, and Haemophilus ducreyi) and 3 controversial microorganisms as pathogens (Mycoplasma hominis, Ureaplasma urealyticum, and Ureaplasma parvum).

Results

The results showed that the STI-MS approach can accurately detect the expected agents, without cross-reaction with other organisms. The limit of detection of each STI-MS assay was ranged from 1.739 to 10.009 copies/reaction, using probit analyses. The verification rate for each target organism of the STI-MS ranged from a minimum of 89.3% to a maximum of 100%, using conventional assays and ultrasensitive digital PCR to confirm the STI-MS-positive results. To further evaluate the clinical performance of this assay, 241 clinical specimens (124 urethral/cervical swabs and 117 urine) were tested in parallel using the STI-MS assay and monoplex real-time PCR for each agent. The overall validation parameters of STI-MS were extremely high including sensitivity (from 85.7% to 100%), specificity (from 92.3% to 100%), PPV (from 50% to 100%), and NPV (from 99.1% to 100%) for each target.

Conclusion

STI-MS is a useful high-throughput screening tool for detecting mixed infections of STIs and has great potential for application in large-scale epidemiological programs for specific microorganisms of STI.

Evaluation of the performance of nucleic acid amplification tests (NAATs) in detection of chlamydia and gonorrhoea infection in vaginal specimens relative to patient infection status: a systematic review

OBJECTIVE

We evaluated the performance of nucleic acid amplification tests (NAATs) using vaginal specimens in comparison to specimens from the cervix or urine in their ability to detect chlamydia and gonorrhoea infection in women based on patient infection status (PIS).

DESIGN

Systematic review.

DATA SOURCES

EMBASE and Ovid MEDLINE databases were searched through 3 October 2017.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

We included studies that tested samples from the vagina and ≥1 other site (cervix and/or urine) with ≥2 NAATs for chlamydia and ≥2 NAATs or 1 NAAT and culture for gonorrhoea for each site.

DATA EXTRACTION AND SYNTHESIS

Performance is defined as the sensitivity of a NAAT using a specimen site and PIS of the patient. We assessed risk of bias using modified QUADAS-2.

RESULTS

Nine publications met the inclusion criteria (eight for chlamydia; six for gonorrhoea) and were narratively reviewed. Pooled summary estimates were not calculated due to the variable methodology and PIS definitions. Tests performed on vaginal specimens accomplished similar performance to cervical and urine specimens for chlamydia (range of performance estimates: vaginal 65%-100%, cervical 59%-97%, urine 57%-100%) and gonorrhoea (vaginal 64%-100%, cervical 85%-100%, urine 67%-94%). Vaginal specimens were estimated to have a performance >80% for chlamydia and gonorrhoea infections in all but one study.

CONCLUSIONS

Performance of the NAATs for chlamydia and gonorrhoea detection using vaginal specimens was similar to that of cervical and urine specimens relative to PIS. As vaginal samples have a higher acceptability and lower cost, the study can support clinical testing guidelines by providing evidence that vaginal samples are a suitable alternative to traditionally used specimens.

The Additive Value of Pelvic Examinations to History in Predicting Sexually Transmitted Infections for Young Female Patients With Suspected Cervicitis or Pelvic Inflammatory Disease

STUDY OBJECTIVE

We evaluate the additive value of pelvic examinations in predicting sexually transmitted infection for young female patients with suspected cervicitis or pelvic inflammatory disease in a pediatric emergency department (ED).

METHODS

This was a prospective observational study of female patients aged 14 to 20 years who presented to an urban academic pediatric ED with a complaint of vaginal discharge or lower abdominal pain. Enrolled patients provided a urine sample for chlamydia, gonorrhea, and trichomonas testing, which served as the criterion standard for diagnosis. A practitioner (pediatric ED attending physician, emergency medicine or pediatric resident, pediatric ED fellow, or advanced practice provider) obtained a standardized history from the patient to assess for cervicitis or pelvic inflammatory disease according to the Centers for Disease Control and Prevention criteria. They then recorded the likelihood of cervicitis or pelvic inflammatory disease on a 100-mm visual analog scale. The same practitioner then performed a pelvic examination and again recorded the likelihood of cervicitis or pelvic inflammatory disease on a visual analog scale with this additional information. Using the results of the urine sexually transmitted infection tests, the practitioner calculated and compared the test characteristics of history alone and history with pelvic examination.

RESULTS

Two hundred eighty-eight patients were enrolled, of whom 79 had positive urine test results for chlamydia, gonorrhea, or trichomonas, with a sexually transmitted infection rate of 27.4% (95% confidence interval [CI] 22.6% to 32.8%). The sensitivity of history alone in diagnosis of cervicitis or pelvic inflammatory disease was 54.4% (95% CI 42.8% to 65.5%), whereas the specificity was 59.8% (95% CI 52.8% to 66.4%). The sensitivity of history with pelvic examination in diagnosis of cervicitis or pelvic inflammatory disease was 48.1% (95% CI 36.8% to 59.5%), whereas the specificity was 60.7% (95% CI 53.8% to 67.3%). The information from the pelvic examination changed management in 71 cases; 35 of those cases correlated with the sexually transmitted infection test and 36 did not.

CONCLUSION

For young female patients with suspected cervicitis or pelvic inflammatory disease, the pelvic examination does not increase the sensitivity or specificity of diagnosis of chlamydia, gonorrhea, or trichomonas compared with taking a history alone. Because the test characteristics for the pelvic examination are not adequate, its routine performance should be reconsidered.

Comparison of cobas 4800, m2000, Viper XTR, and Infinity 80 Automated Instruments When Processing Urine Specimens for the Diagnosis of Chlamydia trachomatis and Neisseria gonorrhoeae

OBJECTIVES

North American and European advisory groups recommend testing for Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) with nucleic acid amplification tests. Testing is often performed on automated instruments. The objectives of this study were to process urines for the diagnosis of CT and NG and to examine workflow procedures and outcomes.

METHODS

While processing 1, 24, 48, 96, and 192 urine specimens on 3 batch-mode systems which use 96-well plates: cobas 4800, m2000, and Viper XTR and the random access cartridge testing GeneXpert Infinity 80, we measured assay performance, hands-on time for processing and maintenance, reagents and plastics consumption, time required to obtain results, and testing accuracy.

RESULTS

The Infinity 80 required the least hands-on time for single specimens and smaller batches, whereas the Viper XTR and m2000 required the most hands-on time for all batch sizes. Cumulative daily, weekly, and monthly maintenance was highest for the Viper XTR and lowest for Infinity 80. All batch-mode instruments consumed large amounts of disposables. Time to results was shortest for the Infinity 80, and the Viper XTR provided the shortest time for the batch-mode instruments. All systems showed similar diagnostic accuracy.

CONCLUSIONS

Because detection performances were similar, issues of hands-on time, maintenance, time to results, and consumables are important operational factors for the diagnosis and treatment of CT/NG infections.

Underdiagnosis of Chlamydia trachomatis and Chlamydia psittaci revealed by introduction of respiratory multiplex PCR assay with Chlamydiaceae family primers

We describe unanticipated detection of respiratory infection with Chlamydia trachomatis and Chlamydia psittaci after introduction of respiratory multiplex polymerase chain reaction assay that includes Chlamydiaceae family primers. We detected cases of pediatric C. trachomatis and of adult C. psittaci infection in patients with previously unrecognized risk factors. Directed testing for C. trachomatis and C. psittaci based on clinical features and risk factors alone is likely to miss the majority of infected cases.

Cross-sectional study to evaluate Trichomonas vaginalis positivity in women tested for Neisseria gonorrhoeae and Chlamydia trachomatis, attending genitourinary medicine and primary care clinics in Bristol, South West England

BACKGROUND

Highly sensitive, commercial nucleic acid amplification tests (NAAT) for Trichomonas vaginalis have only recently been recommended for use in the UK. While testing for T. vaginalis is routine in symptomatic women attending genitourinary medicine (GUM) clinics, it is rare in asymptomatic women or those attending primary care. The aim of this study was to evaluate the positivity of T. vaginalis using a commercial NAAT, in symptomatic and asymptomatic women undergoing testing for chlamydia and gonorrhoea in GUM and primary care settings.

METHODS

Samples from 9186 women undergoing chlamydia and gonorrhoea testing in South West England between May 2013 and Jan 2015 were also tested for T. vaginalis by NAAT alongside existing tests.

RESULTS

T. vaginalis positivity using NAAT was as follows: in GUM 4.5% (24/530, symptomatic) and 1.7% (27/1584, asymptomatic); in primary care 2.7% (94/3499, symptomatic) and 1.2% (41/3573, asymptomatic). Multivariable regression found that in GUM older age, black ethnicity and deprivation were independent risk factors for T. vaginalis infection. Older age and deprivation were also risk factors in primary care. Testing women presenting with symptoms in GUM and primary care using TV NAATs is estimated to cost £260 per positive case diagnosed compared with £716 using current microbiological tests.

CONCLUSIONS

Aptima TV outperforms existing testing methods used to identify T. vaginalis infection in this population. An NAAT should be used when testing for T. vaginalis in women who present for testing with symptoms in primary care and GUM, based on test performance and cost.

[Methods of rapid diagnosis in clinical microbiology: Clinical needs]

The diagnostic methods of infectious diseases should be fast, accurate, simple and affordable. The speed of diagnosis can play a crucial role in healing the patient, allowing the administration of appropriate antibiotic treatment. One aspect that increasingly determines the need for rapid diagnostic techniques is the increased rates of serious infections caused by multidrug resistant bacteria, which cause a high probability of error in the empirical treatment. Some of the conventional methods such as Gram staining or antigen detection can generate results in less than 1 hour but lack sensitivity. Today we are witnessing a major change in clinical microbiology laboratories with the technological advances such as molecular diagnostics, digital microbiology and mass spectrometry. There are several studies showing that these changes in the microbiological diagnosis reduce the generation time of the test results, which has an obvious clinical impact. However, if we look into the future, other new technologies which will cover the needs required for a rapid microbiological diagnosis are on the horizon. This review provides an in depth analysis of the clinical impact that the implementation of rapid diagnostic techniques will have on unmet clinical needs.

Hierarchical group testing for multiple infections

Group testing, where individuals are tested initially in pools, is widely used to screen a large number of individuals for rare diseases. Triggered by the recent development of assays that detect multiple infections at once, screening programs now involve testing individuals in pools for multiple infections simultaneously. Tebbs, McMahan, and Bilder (2013, Biometrics) recently evaluated the performance of a two-stage hierarchical algorithm used to screen for chlamydia and gonorrhea as part of the Infertility Prevention Project in the United States. In this article, we generalize this work to accommodate a larger number of stages. To derive the operating characteristics of higher-stage hierarchical algorithms with more than one infection, we view the pool decoding process as a time-inhomogeneous, finite-state Markov chain. Taking this conceptualization enables us to derive closed-form expressions for the expected number of tests and classification accuracy rates in terms of transition probability matrices. When applied to chlamydia and gonorrhea testing data from four states (Region X of the United States Department of Health and Human Services), higher-stage hierarchical algorithms provide, on average, an estimated 11% reduction in the number of tests when compared to two-stage algorithms. For applications with rarer infections, we show theoretically that this percentage reduction can be much larger.

Estimating the prevalence of multiple diseases from two-stage hierarchical pooling

Testing protocols in large-scale sexually transmitted disease screening applications often involve pooling biospecimens (e.g., blood, urine, and swabs) to lower costs and to increase the number of individuals who can be tested. With the recent development of assays that detect multiple diseases, it is now common to test biospecimen pools for multiple infections simultaneously. Recent work has developed an expectation-maximization algorithm to estimate the prevalence of two infections using a two-stage, Dorfman-type testing algorithm motivated by current screening practices for chlamydia and gonorrhea in the USA. In this article, we have the same goal but instead take a more flexible Bayesian approach. Doing so allows us to incorporate information about assay uncertainty during the testing process, which involves testing both pools and individuals, and also to update information as individuals are tested. Overall, our approach provides reliable inference for disease probabilities and accurately estimates assay sensitivity and specificity even when little or no information is provided in the prior distributions. We illustrate the performance of our estimation methods using simulation and by applying them to chlamydia and gonorrhea data collected in Nebraska. Copyright © 2016 John Wiley & Sons, Ltd.

Diagnostic Procedures to Detect Chlamydia trachomatis Infections

The intracellular life style of chlamydia and the ability to cause persistent infections with low-grade replication requires tests with high analytical sensitivity to directly detect C. trachomatis (CT) in medical samples. Nucleic acid amplification tests (NAATs) are the most sensitive assays with a specificity similar to cell culture and are considered the method of choice for CT detection. In addition, NAATs can be performed on various clinical specimens that do not depend on specific transport and storage conditions, since NAATs do not require infectious bacteria. In the case of lower genital tract infections, first void urine and vaginal swabs are the recommended specimens for testing males and females, respectively. Infections of anorectal, oropharyngeal and ocular epithelia should also be tested by NAAT analysis of corresponding mucosal swabs. In particular, anorectal infections of men who have sex with men (MSM) should include evaluation of lymphogranuloma venereum (LGV) by identification of genotypes L1, L2 or L3. Detection of CT antigens by enzyme immunoassay (EIAs) or rapid diagnostic tests (RDTs) are unsuitable due to insufficient sensitivity and specificity. Recent PCR-based RDTs, however, are non-inferior to standard NAATs, and might be used at the point-of-care. Serology finds application in the diagnostic work-up of suspected chronic CT infection but is inappropriate to diagnose acute infections.

2015 UK national guideline for the management of infection with Chlamydia trachomatis

This guideline offers recommendations on the diagnostic tests, treatment regimens and health promotion principles needed for the effective management of Chlamydia trachomatis genital infection. It covers the management of the initial presentation, as well the prevention of transmission and future infection. The guideline is aimed at individuals aged 16 years and older presenting to healthcare professionals working in departments offering Level 3 care in sexually transmitted infections management within the UK. However, the principles of the recommendations should be adopted across all levels, using local care pathways where appropriate.

Evaluation of the new AmpliSens multiplex real-time PCR assay for simultaneous detection of Neisseria gonorrhoeae, Chlamydia trachomatis, Mycoplasma genitalium, and Trichomonas vaginalis

In this study, we performed an evaluation of the new CE-marked multiplex real-time AmpliSens N.gonorrhoeae/C.trachomatis/M.genitalium/T.vaginalis-MULTIPRIME-FRT PCR assay compared to APTIMA tests, i.e., APTIMA COMBO 2 assay, APTIMA Trichomonas vaginalis assay (FDA-approved), and two different APTIMA Mycoplasma genitalium assays (research use only; one of them only used for discrepancy analysis). Vaginal swabs (n = 209) and first-void urine (FVU) specimens from females (n = 498) and males (n = 554), consecutive attendees (n = 1261) at a dermatovenerological clinic in Sweden, were examined. The sensitivity of the AmpliSens PCR assay for detection of C. trachomatis (6.3% prevalence), M. genitalium (5.7% prevalence), N. gonorrhoeae (0.3% prevalence), and T. vaginalis (0.08% prevalence) was 97.5% (95% confidence interval (CI): 91.2-99.6%), 81.9% (95% CI: 70.7-89.7%), 100% (95% CI: 40.2-100%) and 100% (95% CI: 16.5-100%), respectively. The specificity of the AmpliSens PCR assay was 100% (95% CI: 99.6-100%) for all agents. The analytical sensitivity and specificity for N. gonorrhoeae detection was excellent, i.e., 55 international gonococcal strains detected and 135 isolates of 13 non-gonococcal Neisseria species were negative. In conclusion, the multiplex real-time AmpliSens N.gonorrhoeae/C.trachomatis/M.genitalium/T.vaginalis-MULTIPRIME-FRT PCR assay demonstrated high sensitivity and excellent specificity for the detection of C. trachomatis, N. gonorrhoeae, and T. vaginalis, and excellent specificity but suboptimal sensitivity for M. genitalium detection.

Self-Collected versus Clinician-Collected Sampling for Chlamydia and Gonorrhea Screening: A Systemic Review and Meta-Analysis

BACKGROUND

The increases in STI rates since the late 1990s in Canada have occurred despite widespread primary care and targeted public health programs and in the setting of universal health care. More innovative interventions are required that would eliminate barriers to STI testing such as internet-based or mail-in home and community service testing for patients that are hard to reach, who refuse to go for clinician-based testing, or who decline an examination. Jurisdictions such as New Zealand and some American states currently use self-collected sampling, but without the required evidence to determine whether self-collected specimens are as accurate as clinician-collected specimens in terms of chlamydia and gonorrhea diagnostic accuracy. The objective of the review is to compare self-collected vaginal, urine, pharyngeal and rectal samples to our reference standard - clinician-collected cervical, urethral, pharyngeal and rectal sampling techniques to identify a positive specimen using nucleic acid amplification test assays.

METHODS

The hierarchical summary receiver operating characteristic and the fixed effect models were used to assess the accuracy of comparable specimens that were collected by patients compared to clinicians. Sensitivity and specificity estimates with 95% confidence intervals (CI) were reported as our main outcome measures.

FINDINGS

We included 21 studies based on over 6100 paired samples. Fourteen included studies examined chlamydia only, 6 compared both gonorrhea and chlamydia separately in the same study, and one examined gonorrhea. The six chlamydia studies comparing self-collection by vaginal swab to a clinician-collected cervical swab had the highest sensitivity (92%, 95% CI 87-95) and specificity (98%, 95% CI 97-99), compared to other specimen-types (urine/urethra or urine/cervix). Six studies compared urine self-samples to urethra clinician-collected samples in males and produced a sensitivity of 88% (95% CI 83-93) and a specificity of 99% (95% CI 0.94-0.99). Taking into account that urine samples may be less sensitive than cervical samples, eight chlamydia studies that compared urine self-collected verses clinician-collected cervical samples had a sensitivity of 87% (95% CI 81-91) and high specificity of 99% (95% CI 0.98-1.00). For gonorrhea testing, self-collected urine samples compared to clinician-collected urethra samples in males produced a sensitivity of 92% (95% CI 83-97) and specificity of 99% (95% CI 0.98-1.00).

CONCLUSION

The sensitivity and specificity of vaginal self-collected swabs compared to swabs collected by clinicians supports the use of vaginal swab as the recommended specimen of choice in home-based screening for chlamydia and gonorrhea. Urine samples for gonorrhea collected by men had comparably high sensitivity and specificity, so could be recommended as they can be left at room temperature for several days, allowing for the possibility of mail-in home-based testing. In populations that may not go for testing at all, do not have the option of clinical testing, or who refuse a clinical examination, self-collected screening would be a good alternative. We recommend that guidelines on how to self-collect gonorrhea and chlamydia urine, vaginal, rectal and pharyngeal specimens be published.

Gonorrhoea notifications and nucleic acid amplification testing in a very low-prevalence Australian female population

OBJECTIVES

To examine whether the rapid increase of gonorrhoea notifications in Victoria, Australia, identified by nucleic acid amplification test (NAAT) is supported by similar changes in diagnoses by culture, which has higher specificity, and to determine the proportion of tests positive among women tested.

DESIGN, SETTING AND PARTICIPANTS

Retrospective analysis of Medicare reporting of dual NAATs in Victoria, Victorian Department of Health gonorrhoea notifications, and gonorrhoea culture data at the Melbourne Sexual Health Centre (MSHC), among women, 2008 to 2013.

MAIN OUTCOME MEASURES

Gonorrhoea notifications and testing methods.

RESULTS

Gonorrhoea cases identified by NAAT increased from 98 to 343 cases over the study period. Notifications by culture alone decreased from 19 to five cases. The proportion of NAATs positive for gonorrhoea in Victoria was low (0.2%-0.3%) and did not change over time (P for trend, 0.66). Similarly, the proportion of women tested at the MSHC for gonorrhoea who tested positive (0.4%-0.6%) did not change over time (P for trend, 0.70). Of untreated women who had a positive NAAT result for gonorrhoea and were referred to the MSHC, 10/25 were confirmed by culture.

CONCLUSIONS

The positivity of gonorrhoea in women identified by culture remains stable over time. Using NAAT for gonorrhoea screening in low-prevalence populations will result in many false positives. Positive NAAT results among low-risk women should be regarded as doubtful, and confirmatory cultures should be performed.

Evaluation of the Versant CT/GC DNA 1.0 assay (kPCR) for the detection of extra-genital Chlamydia trachomatis and Neisseria gonorrhoeae infections

Screening for extra-genital Chlamydia trachomatis and Neisseria gonorrhoeae infections is a crucial component for sexually transmitted diseases management, even if at present days no commercial methods have been approved for use on pharyngeal and rectal specimens by the US FDA or have received the conformity CE marking. Here we report the analytical sensitivities of the Versant CT/GC 1.0 assay (Siemens Healthcare Diagnostics, Tarrytown, NY, USA) on rectal and pharyngeal swabs, and an evaluation about the suitability for this assay with two widely used swab collection devices (E-Swab and eNAT, Copan, Brescia, Italy). The limits of detection for rectal and pharyngeal specimens with the Versant assay were 10 copies/ml and 1.0 copies/ml, for C. trachomatis and N. gonorrhoeae, respectively. False positive results due to the presence of non-gonococcal Neisseria species were excluded when clinical rectal and pharyngeal samples containing organisms identified as N. meningitidis, N. sicca, N. flavescens and N. subflava were tested. Due to its sensitivity and specificity, the Versant assay represents a good choice for the diagnosis of chlamydial and/or gonococcal infections not only in genito-urinary samples, but also on rectal and pharyngeal swabs.

Prevalence of sexually transmitted infections including HIV in street-connected adolescents in western Kenya

PURPOSE

The objectives of this study were to characterise the sexual health of street-connected adolescents in Eldoret, Kenya, analyse gender disparity of risks, estimate the prevalence of sexually transmitted infections (STIs), and identify factors associated with STIs.

METHODS

A cross-sectional study of street-connected adolescents ages 12-21 years was conducted in Eldoret, Kenya. Participants were interviewed and screened for Chlamydia trachomatis, Neisseria gonorrhoeae, Trichomonas vaginalis, herpes simplex virus-2, syphilis and HIV. Descriptive statistics and logistic regression were used to identify factors associated with having any STI.

RESULTS

Of the 200 participants, 81 (41%) were female. 70.4% of females and 60.5% of males reported sexual activity. Of those that participated in at least one STI test, 28% (55/194) had ≥1 positive test, including 56% of females; 14% (28/194) had >1 positive test. Twelve females and zero males (6% overall, 14.8% of females) were HIV positive. Among females, those with HIV infection more frequently reported transactional sex (66.7% vs. 26.1%, p=0.01), drug use (91.7% vs. 56.5%, p=0.02), and reported a prior STI (50.0% vs. 14.7%, p<0.01). Having an adult caregiver was less likely among those with HIV infection (33.3% vs. 71.0%, p=0.04). Transactional sex (AOR 3.02, 95% CI (1.05 to 8.73)), a previous STI (AOR 3.46 95% CI (1.05 to 11.46)) and ≥2 sexual partners (AOR 5.62 95% (1.67 to 18.87)) were associated with having any STI.

CONCLUSIONS

Street-connected adolescents in Eldoret, Kenya are engaged in high-risk sexual behaviours and females in particular have a substantial burden of STIs and HIV. There is a need for STI interventions targeted to street-connected youth.

Analysis of laboratory testing results collected in an enhanced chlamydia surveillance system in Australia, 2008-2010

BACKGROUND

Chlamydial infection is the most common notifiable disease in Australia, Europe and the US. Australian notifications of chlamydia rose four-fold from 20,274 cases in 2002 to 80,846 cases in 2011; the majority of cases were among young people aged less than 29 years. Along with test positivity rates, an understanding of the number of tests performed and the demographics of individuals being tested are key epidemiological indicators. The ACCESS Laboratory Network was established in 2008 to address this issue.

METHODS

The ACCESS Laboratory Network collected chlamydia testing data from 15 laboratories around Australia over a three-year period using data extraction software. All chlamydia testing data from participating laboratories were extracted from the laboratory information system; patient identifiers converted to a unique, non-reversible code and de-identified data sent to a single database. Analysis of data by anatomical site included all specimens, but in age and sex specific analysis, only one testing episode was counted.

RESULTS

From 2008 to 2010 a total of 628,295 chlamydia tests were referred to the 15 laboratories. Of the 592,626 individual episodes presenting for testing, 70% were from female and 30% from male patients. In female patients, chlamydia positivity rate was 6.4% overall; the highest rate in 14 year olds (14.3%). In male patients, the chlamydia positivity rate was 9.4% overall; the highest in 19 year olds (16.5%). The most common sample type was urine (57%). In 3.2% of testing episodes, multiple anatomical sites were sampled. Urethral swabs gave the highest positivity rate for all anatomical sites in both female (7.7%) and male patients (14%), followed by urine (7.6% and 9.4%, respectively) and eye (6.3% and 7.9%, respectively).

CONCLUSIONS

The ACCESS Laboratory Network data are unique in both number and scope and are representative of chlamydia testing in both general practice and high-risk clinics. The findings from these data highlight much lower levels of testing in young people aged 20 years or less; in particular female patients aged less than 16 years, despite being the group with the highest positivity rate. Strategies are needed to increase the uptake of testing in this high-risk group.