A Narrative Review of Where We Are With Point-of-Care Sexually Transmitted Infection Testing in the United States

An Evaluation of the Performance, Patient Acceptability, and Feasibility of a Point-of-Care HIV-Syphilis Assay in an Urban Emergency Department

BACKGROUND

Point-of-care (POC) tests for sexually transmitted infections (STIs) permit delivery of results during the patient's emergency department (ED) encounter. We evaluated performance, patient acceptability, and feasibility of a new duplex POC test, Chembio Dual Path Platform HIV-Syphilis Assay, in an urban ED setting.

METHODS

Convenience sampling approach prioritizing those considered at increased risk for an STI and/or with a history of HIV. For the performance evaluation, participants were tested for HIV/syphilis with the Chembio POC assay and the reference laboratory tests; sensitivity and specificity were determined. For the patient acceptability evaluation, participants completed pre- and post-user surveys. For the feasibility evaluation, ED clinical technicians completed a survey evaluating their perceptions regarding feasibility of use of this POC test.

RESULTS

A total of 327 patients were consented and enrolled. The diagnostic sensitivity and specificity of the Chembio POC assay for HIV were 96.5% (95% confidence interval [CI], 90.1%-99.3%) and 99.6% (95% CI, 97.7%-100.0%), respectively, and for syphilis, the values were 93.9% (95% CI, 85.0%-98.3%) and 99.6% (95% CI, 97.9%-100.0%), respectively. Regarding patient acceptability, 87% trusted the result, and 93% reported that they were more likely to seek treatment if they received a positive STI test result in the ED rather than after the ED visit. Regarding feasibility, 90% of the technicians reported that they would recommend using the test in EDs.

CONCLUSIONS

The Chembio Dual Path Platform HIV-Syphilis POC Assay had excellent performance characteristics when evaluated in an ED population, as well as high perceived acceptability from patients, and feasibility for ED use from clinical technicians. The test may have utility for HIV-syphilis screening among high-risk ED patients.

Sexually Transmitted Infections in the Emergency Department

As the United States faces a worsening epidemic of sexually transmitted infections (STIs), emergency departments (EDs) play a critical role in identifying and treating these infections. The growing health inequities in the distribution and disproportionate impact of STIs add to the urgency of providing high-quality sexual health care through the ED. Changes in population health are reflected in the new Centers for Disease Control recommendations on screening, diagnostic testing, and treatment of STIs. This review covers common, as well as and less common or emerging STIs, and discusses the state-of-the-art guidance on testing paradigms, extragenital sampling, and antimicrobial treatment and prevention of STIs.

Sexually Transmitted Infections in Adolescents and Young Adults: A Cross Section of Public Health

INTRODUCTION

Sexually transmitted infections (STIs) can be caused by a number of microorganisms that vary greatly in size, life cycle, clinical manifestations, and sensitivity to available treatments. Transmission of STIs can occur during unprotected (or condomless) sexual contact and through the exchange of body fluids during any type of activity. The prevalence of sexually transmitted diseases remains high in the world, despite diagnostic and therapeutic improvements for these infectious diseases that rapidly eliminate the contagiousness of patients. Our study determines the prevalence of STI pathogens in adolescents and young adults in the population of the Province of Macerata (Italy). We will analyze data in correspondence to age and gender, and we will compare our results to international studies.

MATERIALS AND METHOD

We analyzed STI test results from the entire database of a Provincial Health Authority for the period 2021-2022. The samples came from the following age groups: 0-12, 13-18, 19-25, and 26-35 from 2021 to 2022. The results came from vaginal and cervical swabs (for females); urethral, rectal, and pharyngeal swabs (for males and females); and seminal fluid (for males) for the following infections: HPV, Chlamydia trachomatis, Mycoplasma genitalium, Ureaplasmas, Gardnerella, Trichomonas vaginalis, Neisseria gonorrhoeae, and Treponema pallidum. The results also came from blood tests for HIV, hepatitis C, hepatitis B, and Treponema pallidum (TPHA, VDRL). In addition, we examined results from urine tests for chlamydia, Neisseria gonorrhoeae, trichomonas, and Treponema pallidum.

CONCLUSIONS

The literature for other countries reports the need for comprehensive, culturally and developmentally sensitive care to address sexuality-related issues in adolescents and young adults, a need that also applies to Italy. These data will be of great importance in adopting evidence-based STI control programs in Marche Region. This study could, indeed, represent a landmark for public health officials and professionals, with the aim of promoting adolescents' access to sexual health services to receive useful information, strengthening preventive measures in younger age groups, and designing sexual education programs.

On The Horizon: Novel Approaches to Sexually Transmitted Infection Prevention

Rates of sexually transmitted infections (STIs), especially cases of infectious and congenital syphilis, are increasing in the United States. Novel strategies for STI prevention are being explored and include doxycycline post-exposure prophylaxis and the potential utility of vaccines against gonorrhea. Self-collection of samples and point of care testing for STI are increasingly being employed in a variety of settings. Both can improve uptake of screening and lead to earlier detection and treatment of incident STI in target populations. Overcoming existing regulatory issues and optimizing implementation of current evidence-based strategies will be key to maximizing future STI prevention efforts. Here we provide an update for primary care providers on selected new strategies for STI prevention either currently available or under development for possible future use.

Microfluidic systems for infectious disease diagnostics

Microorganisms, encompassing both uni- and multicellular entities, exhibit remarkable diversity as omnipresent life forms in nature. They play a pivotal role by supplying essential components for sustaining biological processes across diverse ecosystems, including higher host organisms. The complex interactions within the human gut microbiota are crucial for metabolic functions, immune responses, and biochemical signalling, particularly through the gut-brain axis. Viruses also play important roles in biological processes, for example by increasing genetic diversity through horizontal gene transfer when replicating inside living cells. On the other hand, infection of the human body by microbiological agents may lead to severe physiological disorders and diseases. Infectious diseases pose a significant burden on global healthcare systems, characterized by substantial variations in the epidemiological landscape. Fast spreading antibiotic resistance or uncontrolled outbreaks of communicable diseases are major challenges at present. Furthermore, delivering field-proven point-of-care diagnostic tools to the most severely affected populations in low-resource settings is particularly important and challenging. New paradigms and technological approaches enabling rapid and informed disease management need to be implemented. In this respect, infectious disease diagnostics taking advantage of microfluidic systems combined with integrated biosensor-based pathogen detection offers a host of innovative and promising solutions. In this review, we aim to outline recent activities and progress in the development of microfluidic diagnostic tools. Our literature research mainly covers the last 5 years. We will follow a classification scheme based on the human body systems primarily involved at the clinical level or on specific pathogen transmission modes. Important diseases, such as tuberculosis and malaria, will be addressed more extensively.

Heterogeneity in practitioner-reported barriers to use, cost considerations and priorities for point of care sexually transmitted infection tests on surveys across seven years

BACKGROUND

Point of care diagnostic tests (POCTs) for sexually transmitted infections (STIs) have the potential to improve STI care worldwide. However, barriers to adoption, cost considerations and practitioner priorities may not be uniform globally and over time. We conducted two surveys, 7 years apart, among members of the International Union Against Sexually Transmitted Infections (IUSTI), and compare results here.

METHODS

Surveys were given to members attending two IUSTI conferences in 2012 (Australia) and 2019 (Estonia). Descriptive analyses were performed and chi-square or Fisher's exact tests conducted.

RESULTS

Amongst N = 190 participants in 2012 and N = 166 in 2019, 61% in 2012 and 77% in 2019 were from high-income countries (HICs). In 2012, 84% of respondents from low- and middle-income countries (LMICs) and 70% from HICs thought cost of test was more important than amount of reimbursement. Trends were similar in 2019. In 2012, unreliability was considered the most important barrier to POCT use by all groups, followed by being laboratory-driven and complexity. In 2019, time frame was considered most important, followed by unreliability and being laboratory-driven. In 2012, the top priority for POCT development among LMIC respondents was early HIV seroconversion (31%), versus chlamydia (57%) for HICs. In 2019, chlamydia remained top priority for HICs (40%), followed by early HIV seroconversion (19%) and gonorrhea (17%); top priorities for LMICs were chlamydia (26%), HPV (24%), and early HIV seroconversion (21%).

CONCLUSIONS

Practitioner priorities for STI POCTs may be shifting. Cost may be critical to adoption in all settings. Larger studies are needed to verify findings.

Outpatient sexually transmitted infection testing and treatment patterns in the United States: a real-world database study

BACKGROUND

Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) are the most common notifiable sexually transmitted infections (STIs) in the United States. Because symptoms of these infections often overlap with other urogenital infections, misdiagnosis and incorrect treatment can occur unless appropriate STI diagnostic testing is performed in clinical settings. The objective of this study was to describe STI diagnostic testing and antimicrobial treatment patterns and trends among adolescent and adult men and women with lower genitourinary tract symptoms (LGUTS).

METHODS

We analyzed insurance claims data from the IBM® MarketScan® Research Databases. Patients included were between 14 and 64 years old with LGUTS as determined by selected International Classification of Diseases codes between January 2010 and December 2019. Testing of STIs and relevant drug claims were captured, and distribution of testing patterns and drug claims were described.

RESULTS

In total, 23,537,812 episodes with LGUTS (87.4% from women; 12.6% from men) were analyzed from 12,341,154 patients. CT/NG testing occurred in only 17.6% of all episodes. For episodes where patients received treatment within 2 weeks of the visit date, 89.3% received treatment within the first 3 days (likely indicating presumptive treatment), and 77.7% received it on the first day. For women with pelvic inflammatory disease and men with orchitis/epididymitis and acute prostatitis, ≤ 15% received CT/NG testing, and around one-half received antibiotic treatment within 3 days.

CONCLUSIONS

Our study revealed low CT/NG testing rates, even in patients diagnosed with complications commonly associated with these STIs, along with high levels of potentially inappropriate presumptive treatment. This highlights the need for timely and accurate STI diagnosis in patients with LGUTS to inform appropriate treatment recommendations.

The impact of COVID-19 pandemic on technologic and process innovation in point-of-care diagnostics for sexually transmitted infections

The STI diagnostic landscape of FDA cleared tests for use at point-of-care (POC), as well as those emergency use authorized for COVID-19 are reviewed; some of these COVID-19 diagnostics may have platform potential as STI diagnostics. Finally, process innovation is described with self-collection and hub-and-spoke mail-in to reference lab models. Movement of Clinical Laboratory Improvement Amendments (CLIA)-waived POC tests to over-the-counter formats will make tests more accessible to consumers. Together with public health messaging, these measures could accelerate STI and COVID-19 syndemic diagnostic solutions.

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.

Point-of-Care Testing for Sexually Transmitted Infections

Point-of-care testing for sexually transmitted infections is essential for controlling transmission and preventing sequelae in high-risk populations. Since the World Health Organization published the ASSURED criteria, point-of-care testing has improved for use in large population screening and rapid testing that prevents loss of clinical follow-up. Recent advancements have been advantageous for low-resource areas allowing testing at a minimal cost without reliable electricity or refrigeration. Point-of-care nucleic acid detection and amplification techniques are recommended, but are often inaccessible in low-resource areas. Future advancements in point-of-care diagnostic testing should focus on improving antibody-based assays, monitoring viral loads, and detecting antimicrobial resistance.

Sensitivity and Specificity of two Investigational Point of care Tests for Syphilis and HIV (PoSH Study) for the diagnosis and treatment of infectious syphilis in Canada: a cross sectional study

OBJECTIVES

Single visit testing and treatment for syphilis can reduce follow-up visits. The objectives of this study were to evaluate the performance and treatment outcomes of two dual syphilis/HIV point-of care tests (POCT).

METHODS

Participants aged 16 years and older were offered concurrent syphilis/HIV POCT from fingerstick blood using two extremely rapid (<5 minutes) devices [MedMira Multiplo Rapid TP/HIV Test and INSTI Multiplex HIV1/2 Syphilis Ab test]. Those with positive POCT results were offered same day syphilis treatment and linkage to HIV care. Nurses performed testing at two emergency departments, First Nations community, correctional facility and STI clinic. POCT results were compared to standard serological testing. Sensitivity and specificity were calculated.

RESULTS

Between August 2020 and February 2022, 1526 visits were completed. Both POCT accurately identified participants with HIV (sensitivity=100·0% [24/24], 95% CI=86·2-100·0%, specificity=99·6% [1319/1324], 95% CI=99·1-99·8%), linking 24 HIV cases to care. Both tests were most sensitive with an RPR > 8 dilutions (Multiplo: sensitivity=98·3% [231/235], 95% CI=95·7-99·3%, specificity=99·5% [871/875], 95% CI=98·8-99·8%, INSTI Multiplex: sensitivity=97·9% [230/235], 95% CI=95·1-99·1%, specificity=99·8% [873/875], 95% CI=99·2-99·9%) and least sensitive with non-reactive RPR (Multiplo: sensitivity=54·1% [59/109], 95% CI=44·8-63·2%, specificity=99·5% [871/875], 95% CI=98·8-99·8%, INSTI Multiplex: sensitivity=28·4% [31/109], 95% CI=20·8-37·5%, specificity=99·8% [873/875], 95% CI=99·2-99·9%). 87·0% with a positive POCT were treated the same day.

CONCLUSIONS

Two extremely rapid (<5 minutes) dual syphilis/HIV POCT showed excellent sensitivity and specificity for the diagnosis of active syphilis (RPR > 1:8 dilutions) and HIV and confirmed the ability to offer single visit testing and treatment for syphilis and linkage to HIV care in diverse clinical settings.

Syphilis

Syphilis is an important public health problem in the U.S. and many high-income nations. The rates of syphilis continue to increase and there is an urgent need for medical providers of a variety of backgrounds to recognize this disease. In this review, we cover the key clinical findings of syphilis and provide an overview of the diagnosis and management of this disease in adults.

Trichomoniasis

Trichomoniasis is the most common nonviral sexually transmitted infection worldwide. It has been associated with a variety of adverse sexual and reproductive health outcomes for both men and women. In this review, the authors discuss updates in its epidemiology, pathophysiology, clinical significance, diagnosis, and treatment.

An amplification-free, 16S rRNA test for Neisseria gonorrhoeae in urine

An amplification-free, nanopore-based nucleic acid detection platform has been demonstrated for rapid, 16S rRNA sequence-specific detection of Neisseria gonorrhoeae at 10-100 CFU mL^-1 in human urine against background bacterial flora at 1000 CFU mL^-1. Gonorrhea is a very common notifiable communicable disease, antibiotic resistant strains have emerged, and the rate of reported gonococcal infections continues to increase. Since rapid clinical identification of bacterial pathogens in clinical samples is needed to guide proper antibiotic treatment and to control disease spread, it is important to engineer rapid, sensitive, selective, and inexpensive point-of-care (POC) diagnostic devices for pathogens such as N. gonorrhoeae. Our detector technology is based on straightforward conductometric detection of sustained blockage of a glass nanopore. Charge neutral, complementary peptide nucleic acid probes are conjugated to polystyrene beads to capture N. gonorrhoeae 16S rRNA selectively. In the presence of an electric field applied externally through a glass nanopore, the PNA-microbead conjugates that acquire substantial negative charge upon target hybridization are driven to the smaller diameter nanopore. At least partial blockage of the nanopore results in a sustained drop in ionic current that can be measured easily with simple electronics. The ability to detect N. gonorrhoeae over the range of 10 to 100 CFU mL^-1 spiked in human urine was demonstrated successfully with estimated sensitivity and specificity of ∼98% and ∼100%, respectively. No false positives were observed for the control group of representative background flora (E. coli, K. pneumoniae, and E. faecalis) at 1000 CFU mL^-1. Also, N. gonorrhoeae at 50 CFU mL^-1 was successfully detected against 1000 CFU mL^-1 of background flora in urine. These results suggest that this amplification-free technology may serve as the basis for rapid, inexpensive, low-power detection of pathogens in clinical samples at the POC.

Ratiometric PCR in a Portable Sample-to-Result Device for Broad-Based Pathogen Identification

Polymerase chain reaction (PCR)-based diagnostic testing is the gold standard method for pathogen identification (ID) with recent developments enabling automated PCR tests for point-of-care (POC) use. However, multiplexed identification of several pathogens in PCR assays typically requires optics for an equivalent number of fluorescence channels, increasing instrumentation's complexity and cost. In this study, we first developed ratiometric PCR that surpassed one target per color barrier to allow multiplexed identification while minimizing optical components for affordable POC use. We realized it by amplifying pathogenic targets with fluorescently labeled hydrolysis probes with a specific ratio of red-to-green fluorophores for each bacterial species. We then coupled ratiometric PCR and automated magnetic beads-based sample preparation within a thermoplastic cartridge and a portable droplet magnetofluidic platform. We named the integrated workflow POC-ratioPCR. We demonstrated that the POC-ratioPCR could detect one out of six bacterial targets related to urinary tract infections (UTIs) in a single reaction using only two-color channels. We further evaluated POC-ratioPCR using mock bacterial urine samples spiked with good agreement. The POC-ratioPCR presents a simple and effective method for enabling broad-based POC PCR identification of pathogens directly from crude biosamples with low optical instrumentation complexity.

Laboratory evaluation of two point-of-care test kits for the identification of infectious syphilis

Background

Syphilis is a sexually transmitted disease that can have atypical clinical presentations. Conventional laboratory tests to confirm the diagnosis are not rapid enough to affect clinical decision on treatment and contact tracing. Rapid point-of-care tests (POCT) can be useful for control of infectious diseases; however, no POCT for syphilis detection is currently available in Canada. The aim of this study is to evaluate two POCTs (RevealTM Rapid TP (Treponema pallidum) Antibody test and DPP® Syphilis Screen and Confirm test) for detection of infectious syphilis.

Methods

One hundred serum samples with known syphilis serological status, based on treponemal and non-treponemal test results, were analysed in the laboratory with two POCTs by two independent operators in a blind fashion. Results were analysed to evaluate their ability to detect infectious syphilis.

Results

The Reveal Rapid TP Antibody POCT showed an overall sensitivity of 95.0% and a specificity of 83.3%, while the DPP Syphilis Screen and Confirm POCT showed a sensitivity of 87.5% and a specificity of 98.3%. Both POCTs gave a sensitivity of 100% on active syphilis samples with Venereal Disease Research Laboratory (VDRL) titres of greater than 1:4, but their sensitivities decreased for samples with low VDRL titres. Both POCTs gave weakly or very weakly reactive results on 11.3%-25.0% of the treponemal antibody positive samples.

Conclusion

This laboratory evaluation has shown promising results for both POCTs to detect infectious syphilis. Further evaluations in the field would be required to confirm this preliminary finding.

Bridging the gap between development of point-of-care nucleic acid testing and patient care for sexually transmitted infections

The incidence rates of sexually transmitted infections (STIs), including the four major curable STIs - chlamydia, gonorrhea, trichomoniasis and, syphilis - continue to increase globally, causing medical cost burden and morbidity especially in low and middle-income countries (LMIC). There have seen significant advances in diagnostic testing, but commercial antigen-based point-of-care tests (POCTs) are often insufficiently sensitive and specific, while near-point-of-care (POC) instruments that can perform sensitive and specific nucleic acid amplification tests (NAATs) are technically complex and expensive, especially for LMIC. Thus, there remains a critical need for NAAT-based STI POCTs that can improve diagnosis and curb the ongoing epidemic. Unfortunately, the development of such POCTs has been challenging due to the gap between researchers developing new technologies and healthcare providers using these technologies. This review aims to bridge this gap. We first present a short introduction of the four major STIs, followed by a discussion on the current landscape of commercial near-POC instruments for the detection of these STIs. We present relevant research toward addressing the gaps in developing NAAT-based STI POCT technologies and supplement this discussion with technologies for HIV and other infectious diseases, which may be adapted for STIs. Additionally, as case studies, we highlight the developmental trajectory of two different POCT technologies, including one approved by the United States Food and Drug Administration (FDA). Finally, we offer our perspectives on future development of NAAT-based STI POCT technologies.

COVID-19: a gray swan's impact on the adoption of novel medical technologies

The COVID-19 pandemic offers a unique context and opportunity to investigate changes in healthcare professional perceptions towards the adoption of novel medical technologies, such as point-of-care technologies (POCTs). POCTs are a nascent technology that has experienced rapid growth as a result of COVID-19 due to their ability to increase healthcare accessibility via near-patient delivery, including at-home. We surveyed healthcare professionals before and during COVID-19 to explore whether the pandemic altered their perceptions about the usefulness of POCTs. Our network analysis method provided a structure for understanding this changing phenomenon. We uncovered that POCTs are not only useful for diagnosing COVID-19, but healthcare professionals also perceive them as increasingly important for diagnosing other diseases, such as cardiovascular, endocrine, respiratory, and metabolic diseases. Healthcare professionals also viewed POCTs as facilitating the humanization of epidemiology by improving disease management/monitoring and strengthening the clinician-patient relationship. As the accuracy and integration of these technologies into mainstream healthcare delivery improves, hurdles to their adoption dissipate, thereby encouraging healthcare professionals to rely upon them more frequently to diagnose, manage, and monitor diseases. The technological advances made in POCTs during COVID-19, combined with shifting positive perceptions of their utility by healthcare professionals, may better prepare us for the next pandemic.