Swab-yourself Trial With Economic Monitoring and Testing for Infections Collectively (SYSTEMATIC): Part 1. A Diagnostic Accuracy and Cost-effectiveness Study Comparing Clinician-taken vs Self-taken Rectal and Pharyngeal Samples for the Diagnosis of Gonorrhea and Chlamydia

Quality, acceptability and usability of self-sampling kits used by non-healthcare professionals for STI diagnosis in Spain: a single-blind study

OBJECTIVES

Sexually transmitted infections (STIs) have markedly increased over the last decade in Spain, calling for prevention and control innovative approaches. While there is evidence indicating the effectiveness of self-sampling for STI diagnosis, no kits for this purpose have been authorised in Spain.

METHODS

A prospective single-blind cross-sectional study carried out between November and December 2022 in an STI clinic in Madrid, Spain, to determine the validity, feasibility and acceptability of self-sampling kits used by non-healthcare professionals from vagina, pharynx, rectum and urethra to diagnose Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG). Self-samples were compared with samples collected by healthcare professional (HC samples) and analysed by PCR. Frequency of CT and NG diagnosis by sample type was compared using McNemar's test for paired data. Sensitivity and specificity of self-samples for CT and NG diagnosis were also calculated.

RESULTS

306 self-samples from 51 participants were analysed. 80% were men with median age of 33 (IQR: 28-38) years. Self-samples and HC samples showed no significant statistical differences in CT and NG diagnosis. Self-samples had a sensitivity of 81% for CT and 93% for NG, with a specificity of 97% for CT and 95% for NG. More than 90% of participants had no difficulty understanding the kit instructions and 71% expressed high levels of satisfaction with the self-sampling kit.

CONCLUSION

Self-sampling kits for CT and NG diagnosis can be safely and effectively used by non-healthcare professionals in Spain. National strategies for STI prevention and control should prioritise self-sampling strategies.

Using Self-Reported Sexual Positioning as an Indicator for Rectal Chlamydia and Gonorrhea Screening Among Men Who Have Sex With Men in China: A Missed Opportunity

BACKGROUND

Rectal Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) infections among men who have sex with men (MSM) are escalating public health concerns. This study aimed to explore (1) the reliability of self-reported sexual positioning as an indicator for rectal CT and NG screening, and (2) factors associated with rectal CT and NG infections in Shenzhen, China.

METHODS

A cross-sectional study was conducted in 2 settings in Shenzhen, China, from April 1, 2021, to March 31, 2022. Data on sociodemographic characteristics, sexual behaviors, and basic CT knowledge were collected. Urine and self-collected rectal swabs were collected for CT and NG testing.

RESULTS

In total, 195 MSM participated in the study, and 5.1% tested positive for urogenital CT, 29.2% for rectal CT, 1.0% for urogenital NG, and 8.2% for rectal NG. Among those who reported exclusively insertive anal sex, 69.2% of CT infections and 85.7% of NG infections would have remained undetected with urine testing alone. Risk factors for rectal CT infection included engaging in both insertive and receptive anal sex, with a significant association found for coinfection with rectal NG.

CONCLUSIONS

Self-reported sexual positioning was found to be an unreliable indicator for CT and NG screening, as a substantial proportion of infections would have remained undetected. The findings suggest that CT and NG screening in China should be offered to all MSM regardless of self-reported sexual positioning, and that the dual CT/NG testing is recommended.

Testing for extragenital Neisseria gonorrhoeae and Chlamydia trachomatis: At-home pharyngeal and rectal self-swabs are non-inferior to those completed in healthcare settings

INTRODUCTION

The rates of gonorrhea and chlamydia have been increasing in the years preceding the COVID19 pandemic. Because most gonorrhea and chlamydia infections are located in the oropharynx and rectum for men who have sex with men (MSM), and because at-home self-collected swabs for these infections are not licensed by Health Canada or the United States Food and Drug Administration, decreased accessed to in-person care during and since the COVID19 pandemic potentially means missed case findings.

OBJECTIVES

To evaluate the performance of at-home self-collected pharyngeal and rectal swabs for gonorrhea and chlamydia nucleic acid amplification testing.

METHODOLOGY

All persons who contacted our Sexual Health Clinic and who had a clinical indication to complete oral and/or rectal swabs for gonorrhea and chlamydia were invited to complete at-home swabs in advance of their scheduled appointments. We mailed swabs and instructions to those who consented. Participants brought these swabs to their scheduled in clinic appointments, where we repeated the same swabs. All matching swabs were sent to the laboratory for analysis to determine concordance.

RESULTS

From September 8, 2022 to July 18, 2023, we enrolled 296 eligible participants who provided 1184 swabs. For analysis, cancelled specimens and specimens with invalid results were excluded, leaving 1032 swabs for comparison. We identified 66 STI diagnoses in 47 unique participants. Overall accuracy was high (exceeding 99%), except for rectal chlamydia, which was 96.0%. While the performance of self-swabs for chlamydia was lower compared to gonorrhea, at-home swabs identified six chlamydia infections that were missed by in-clinic collected swabs (two pharyngeal, four rectal). Removing these six cases as "false positives" increased overall accuracy for chlamydia detection to 99.7% (pharyngeal) and 97.8% (rectal).

CONCLUSION

Self-collected at-home swabs had good performance acceptable for gonorrhea and chlamydia nucleic acid amplification testing.

Use of Home-Based Self-Collected Dried Blood Spots to Test for Syphilis, Human Immunodeficiency Virus, Hepatitis C and B Virus Infections and Measuring Creatinine Concentration

INTRODUCTION

Home-based self-collected dried blood spot (DBS) sampling could simplify sexual health and preexposure prophylaxis care and reduce sexually transmitted infections (STIs) clinic visits for men who have sex with men (MSM). We compared the performance of DBS to venipuncture collected blood samples to test four STIs and creatinine concentration.

METHODS

We invited MSM clients of the Amsterdam STI clinic to participate. Routinely collected peripheral blood was tested for syphilis treponemal antibody, HIV (HIV Ag/Ab), HCV (antibodies), HBV (HBsAg) and creatinine concentration. Participants received a home kit for DBS sampling, a return envelope and a questionnaire to evaluate the acceptability, feasibility and usability of DBS, measured on 5-point Likert scales, 1 representing complete disagreement and 5 complete agreement. We assessed sensitivity and specificity of DBS versus peripheral blood-based testing.

RESULTS

In 2020 to 2021, we included 410 participants; 211 (51.5%) returned a completed DBS card, 117 (28.5%) returned a partially filled card and 82 (20.0%) did not return a card. The sensitivity for syphilis was 90.8% and the specificity 84.3%. For both HIV Ag/Ab and HBsAg, the sensitivity and specificity were 100.0%. The sensitivity for HCV antibody was 80.0%, and the specificity was 99.2%. The DBS creatinine concentration was a mean of 5.3 μmol/L higher than in venipuncture obtained plasma. Participants' median willingness to take a future DBS was 4 (interquartile range, 3-5).

DISCUSSION

Dried blood spot may be an acceptable method among MSM for STI testing and creatinine follow-up during preexposure prophylaxis use. However, collecting enough blood on DBS cards was a challenge, and sensitivities for syphilis and HCV serology were too low.

Prevalence of Chlamydia infection detected by immunohistochemistry in patients with anorectal ulcer and granulation tissue

Anorectal ulcer with granulation tissue is typically associated with left-sided inflammatory bowel disease or infection. Due to emerging cases of Chlamydia proctitis, we aim to investigate the prevalence of Chlamydia infection using immunohistochemistry (IHC) in anorectal biopsies showing ulcer and granulation tissue. Seventy-seven patients including 60 males and 17 females with mean age of 51 years old were retrospectively identified in surgical pathology archives. Chlamydia IHC was validated with a monoclonal antibody on an index who was positive for Chlamydia by rectal swab nucleic acid amplification test (NAAT), then performed on formalin fixed and paraffin embedded (FFPE) tissue sections. Confirmative molecular test using real-time PCR was performed on DNA extractions of 14 IHC-positive and 14 IHC-negative FFPEs, 18 NAAT-positive, and 5 NAAT-negative cytology specimens. Chlamydia IHC showed strong intracytoplasmic or extracellular sphere morphology in 14 of 77 (18.2 %) FFPEs, including 11 of 60 (18.3 %) males and 3 of 17 (17.6 %) females (age 11-84 years). Eight of 14 (57.1 %) Chlamydia-IHC positive patients had known history of STDs, high-risk behavior, or immunosuppressive conditions. One of 14 (7.1 %) IHC-positive FFEP and 15 of 18 (83.3 %) NAAT-positive cytology cases were confirmed by real-time PCR. Chlamydia inclusions were detected in all 4 randomly selected NAAT and PCR-positive cytology specimens by IHC. Our data suggested that Chlamydia infection is more prevalent than we thought in patients with active proctitis and ulceration. Chlamydia IHC may be performed as a screening test in biopsies to facilitate early detection of this treatable proctitis in high-risk population.

Evaluation of Self-Collected Versus Health Care Professional (HCP)-Performed Sampling and the Potential Impact on the Diagnostic Results of Asymptomatic Sexually Transmitted Infections (STIs) in High-Risk Individuals

Sexually transmitted infections (STIs) are increasing among men who have sex with men (MSM). Screening can improve the detection and outcome of asymptomatic STIs in high-risk populations. Self-sampling may be a resource-optimized strategy; however, its diagnostic reliability compared to testing by healthcare professionals (HCPs) requires further investigation. In this prospective, multicenter cohort study in a high-income country, asymptomatic MSM with a sexual risk profile for STIs were included. Sequential swabs for STI nucleic acid-based diagnosis of Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) were performed after randomization, either through self-sampling or HCP-performed sampling. Baseline demographic information, sexual risk behavior, and acceptance and feedback on self-sampling were recorded using an electronic questionnaire. Out of 236 asymptomatic MSM, 47 individuals (19.9%) tested positive for CT and/or NG through self- or HCP-performed sampling. For CT, the sensitivity was 93.3% for both sampling methods, while for NG, it was 90.0% for self-sampling and 95.0% for HCP-performed sampling. Our study demonstrates that self-sampling for asymptomatic STIs has a comparable diagnostic outcome to HCP-performed sampling, with high acceptance in high-risk MSM.

Self-sampling strategies (with/without digital innovations) in populations at risk of Chlamydia trachomatis and Neisseria gonorrhoeae: a systematic review and meta-analyses

BACKGROUND

Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (GC) resulted in over 200 million new sexually transmitted infections last year. Self-sampling strategies alone or combined with digital innovations (ie, online, mobile or computing technologies supporting self-sampling) could improve screening methods. Evidence on all outcomes has not yet been synthesised, so we conducted a systematic review and meta-analysis to address this limitation.

METHODS

We searched three databases (period: 1 January 2000-6 January 2023) for reports on self-sampling for CT/GC testing. Outcomes considered for inclusion were: accuracy, feasibility, patient-centred and impact (ie, changes in linkage to care, first-time testers, uptake, turnaround time or referrals attributable to self-sampling).We used bivariate regression models to meta-analyse accuracy measures from self-sampled CT/GC tests and obtain pooled sensitivity/specificity estimates. We assessed quality with Cochrane Risk of Bias Tool-2, Newcastle-Ottawa Scale and Quality Assessment of Diagnostic Accuracy Studies-2 tool.

RESULTS

We summarised results from 45 studies reporting self-sampling alone (73.3%; 33 of 45) or combined with digital innovations (26.7%; 12 of 45) conducted in 10 high-income (HICs; n=34) and 8 low/middle-income countries (LMICs; n=11). 95.6% (43 of 45) were observational, while 4.4% (2 of 45) were randomised clinical trials.We noted that pooled sensitivity (n=13) for CT/GC was higher in extragenital self-sampling (>91.6% (86.0%-95.1%)) than in vaginal self-sampling (79.6% (62.1%-90.3%)), while pooled specificity remained high (>99.0% (98.2%-99.5%)).Participants found self-sampling highly acceptable (80.0%-100.0%; n=24), but preference varied (23.1%-83.0%; n=16).Self-sampling reached 51.0%-70.0% (n=3) of first-time testers and resulted in 89.0%-100.0% (n=3) linkages to care. Digital innovations led to 65.0%-92% engagement and 43.8%-57.1% kit return rates (n=3).Quality of studies varied.

DISCUSSION

Self-sampling had mixed sensitivity, reached first-time testers and was accepted with high linkages to care. We recommend self-sampling for CT/GC in HICs but additional evaluations in LMICs. Digital innovations impacted engagement and may reduce disease burden in hard-to-reach populations.

PROSPERO REGISTRATION NUMBER

CRD42021262950.

Chlamydial and Gonococcal Genital Infections: A Narrative Review

Sexually transmitted infections (STIs) constitute one of the leading causes of disease burden worldwide, leading to considerable morbidity, mortality, health expenditures, and stigma. Of note are the most common bacterial STIs, chlamydial and gonococcal infections, whose etiological agents are Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG), respectively. Despite being usually asymptomatic, in some cases these infections can be associated with long-term severe complications, such as pelvic inflammatory disease, chronic pelvic pain, infertility, ectopic pregnancy, and increased risk of other STIs acquisition. As the symptoms, when present, are usually similar in both infections, and in most of the cases these infections co-occur, the dual-test strategy, searching for both pathogens, should be preferred. In line with this, herein we focus on the main aspects of CT and NG infections, the clinical symptoms as well as the appropriate state-of-the-art diagnostic tests and treatment. Cost-effective strategies for controlling CT and NG infections worldwide are addressed. The treatment for both infections is based on antibiotics. However, the continuing global rise in the incidence of these infections, concomitantly with the increased risk of antibiotics resistance, leads to difficulties in their control, particularly in the case of NG infections. We also discuss the potential mechanism of tumorigenesis related to CT infections. The molecular bases of CT and NG infections are addressed, as they should provide clues for control or eradication, through the development of new drugs and/or effective vaccines against these pathogens.

Challenges in Managing Gonorrhea and New Advances in Prevention

Gonorrhea is the second most common bacterial sexually transmitted infection in the United States. Rates are increasing, and multiple challenges compound management, including worsening antimicrobial resistance. New therapeutics, enhanced screening and partner notification, and treatment through point-of-care testing and expedited partner therapy, as well as primary prevention efforts provide opportunities for success in combating these trends.

Regular Testing of HIV and Sexually Transmitted Infections With Self-Collected Samples From Multiple Anatomic Sites to Monitor Sexual Health in Men Who Have Sex With Men: Longitudinal Study

Background

Regular HIV and sexually transmitted infection (STI) testing for men who have sex with men (MSM) is an important means of infection prevention, the adoption of which remains suboptimal in the community.

Objective

On the hypothesis that engagement plays an important role in sexual health monitoring, this study aimed to pilot-test internet-based HIV and STI testing with self-sampling to enhance engagement of MSM with regular testing.

Methods

This 1-year cohort study was conducted on HIV-negative MSM aged 18 years or older. A designated website was set up to enable participants to make appointments for baseline and follow-up visits at 3-monthly intervals. On-site blood sampling was performed for HIV and syphilis tests, along with self-collection of pharyngeal swabs, rectal swabs, and urine samples for Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) testing. Full engagement, as defined by having made at least 3 visits over a 6-12 months’ follow-up period, was compared with partial engagement in the bivariable logistic regression model.

Results

Between August 2019 and October 2020, 204 MSM were recruited, after the exclusion of 2 baseline HIV-positive MSM. The majority (189/204, 92.7%) were Chinese, the median age was 31 (IQR 26-39) years, and 58.0% (116/200) had experience with pre-exposure prophylaxis (PrEP) at baseline. Full engagement (146/204, 71.6%) was associated with incident STI during the follow-ups (odds ratio [OR] 4.23, 95% CI 1.63-10.94), seeking a medical referral after STI detection (OR 10.25, 95% CI 3.25-29.79), and a synchronized schedule of HIV and STI testing with PrEP visits (OR 51.85, 95% CI 19.30-139.34). No incident HIV was detected in the follow-up period. At baseline, the overall STI (CT, NG, or syphilis) prevalence was 30%, with CT at 18%, NG at 13%, and syphilis at 5%. During follow-up, the incidences were 59.08/100 person-years (py) for any STI, 33.05/100 py for CT, 29.86/100 py for NG, and 10.4/100 py for syphilis. The detection rates of CT and NG in urine samples were lower than with pharyngeal swabs and rectal swabs. The scores for convenience, confidence of correct sampling, and accuracy of self-sampling were high (7 to 8 out of 10).

Conclusions

Both baseline prevalence and incidence of STI were high among MSM engaged in regular testing. A high degree of engagement in regular STI and HIV testing was positively associated with incident STI, history of health-seeking behaviors, and perceived convenience of self-sampling. Self-sampling could be introduced as a means of enhancing engagement in regular HIV and STI testing.

Self-testing kit for sexually transmitted infections increases diagnoses while reducing costs

The studyWilson JD, Wallace HE, Loftus-Keeling M, et al. Swab-yourself trial with economic monitoring and testing for infections collectively (SYSTEMATIC): Part 2. A diagnostic accuracy, and cost-effectiveness, study comparing rectal, pharyngeal and urogenital samples analysed individually, versus as a pooled specimen, for the diagnosis of gonorrhoea and chlamydia. Clin Infect Dis 2020;73:3183-93.To read the full NIHR Alert, go to: https://evidence.nihr.ac.uk/alert/sexually-transmitted-infections-self-testing-increases-diagnoses-reduces-costs/.

Rectal specimen self-collection for chlamydia and gonorrhea screening: a cross-sectional feasibility study at a community health center

Background

Men who have sex with men (MSM) are at increased risk for extra-genital sexually transmitted infections (STIs). Without extra-genital screening, many chlamydia and gonorrhea infections would be missed among MSM. Yet, many barriers exist to extra-genital testing, and, in particular, to rectal collection. Self-collection increases screening and detection of asymptomatic chlamydia and gonorrhea among at-risk MSM and transgender women. This feasibility study assessed use of rectal self-collection and its acceptance among patients and primary care providers (PCPs) at a large, general practice community health center. The primary objective of this project was to assess the feasibility of including rectal self-collection as part of an implementation study looking to embed an STI care program in a safety-net primary care setting that would shift routine screening tasks to non-provider clinical team members such as medical assistants and nurses.

Methods

Three PCPs identified and offered rectal self-collection to their MSM and transgender female patients who were due for routine or risk-based STI screening. For those patients who elected to participate in the study, the PCP’s medical assistant (MA) reviewed the self-collection instructions with them as part of their routine preventive care duties, and patients collected their own sample. Patients and PCPs completed brief cross-sectional surveys assessing the self-collection process.

Results

Of 1191 patients with sexual orientation and gender identity (SOGI) data on file who were seen for a medical visit by one of the three PCPs, 87 (7.3%) identified as MSM or transgender female. Seventy-five were due for rectal screening, of whom 33 (44%) were offered and completed rectal self-collection. Survey results indicated that self-collection was acceptable to and preferred over clinician-collection by both PCPs and patients.

Conclusions

This study demonstrated that rectal self-collection is feasible as part of STI screening in a high-volume primary care setting, and can be administered as part of the clinical tasks that MAs routinely conduct. The overall acceptance by both PCPs and patients will allow the inclusion of rectal self-collection in an implementation study looking to increase STI screening at a large community health center by facilitating MA-led collection during medical provider visits and by establishing standalone nurse-led STI visits.