Are Treponema pallidum specific rapid and point-of-care tests for syphilis accurate enough for screening in resource limited settings? Evidence from a meta-analysis

Provider-Reported Barriers in Sexual Health Care Services for Women With Upstream Barriers: The Case of Syphilis and Congenital Syphilis in Southern Colorado, 2022

BACKGROUND

Syphilis and congenital syphilis rates have increased sharply in Colorado in the past 5 years. Congenital syphilis is passed during pregnancy in utero and can cause lifelong physical, developmental, and neurologic problems for the child, or can lead to miscarriage, stillbirth, or early infant death. Congenital syphilis is easily prevented if the mother receives timely testing, treatment, and prenatal care. Providers can play a key role in preventing congenital syphilis for women with social vulnerabilities, who have a higher likelihood of syphilis and/or congenital syphilis infection.

METHODS

We surveyed 23 and interviewed 4 health care providers in southern Colorado in 2022 to record their experiences in providing sexual health care services. We asked providers with direct care experience about perceived barriers in effectively treating syphilis.

RESULTS

The most significant barriers reported in the survey were the cost of treatment (26%) and the loss to follow-up (22%). Interviews revealed further challenges, including discretionary testing procedures, delays in screening results, treatment referral issues, and stigma around substance use and sexual activity.

CONCLUSIONS

Elevated syphilis and congenital syphilis rates pose significant public health challenges. Coordinated interventions are necessary to effectively reduce the transmission of syphilis and congenital syphilis among women with upstream barriers. Potential care solutions include expanding rapid, point-of care testing and treatment options, supporting bicillin delivery or web-based inventory systems, offering anti-stigma training for providers, offering mental and behavioral health resources at providers' clinics, and expanding partnerships with syringe access programs.

Southern African HIV Clinicians Society Guideline for the clinical management of syphilis

Syphilis, 'the great imitator', caused by Treponema pallidum infection, remains a complex and multifaceted disease with a rich history of clinical diversity. This guideline aims to be a comprehensive guide for healthcare workers in Southern Africa, offering practical insights into the epidemiology, pathogenesis, clinical manifestations, diagnostic testing, therapeutic principles, and public health responses to syphilis. Although the syphilis burden has declined over the years, recent data indicate a troubling resurgence, particularly among pregnant women and neonates. This guideline highlights the diagnostic challenges posed by syphilis, stemming from the absence of a single high-sensitivity and -specificity test. While treatment with penicillin remains the cornerstone of treatment, alternative regimens may be used for specific scenarios. We highlight the importance of thorough patient follow-up and management of sex partners to ensure optimal care of syphilis cases. In the context of public health, we emphasise the need for concerted efforts to combat the increasing burden of syphilis, especially within high-risk populations, including people living with HIV.

Syphilis for dermatologists: Current concepts

Dermatologists are familiar with the classic aspects of syphilis. Our objective in this update is to display novel features of sexually acquired syphilis, its pathophysiology, natural history, atypical clinical variants, skin of color, clinical pearls, and prospects. Textbook knowledge, congenital syphilis, epidemiology, and historical data are excluded.

Resurgence of congenital syphilis: new strategies against an old foe

Congenital syphilis is a major global cause of fetal loss, stillbirth, neonatal death, and congenital infection. In 2020, the global rate of congenital syphilis was 425 cases per 100 000 livebirths-substantially higher than WHO's elimination target of 50 cases per 100 000 livebirths. Case rates are rising in many high-income countries, but remain low compared with those in low-income and middle-income settings. This Review aims to summarise the current epidemiology and knowledge on transmission and treatment of syphilis in pregnancy, and proposes measures to reduce the rising incidence seen worldwide. We also describe emerging diagnostic and treatment tools to prevent vertical transmission and improve management of congenital syphilis. Finally, we outline a programme of public health priorities, which include research, clinical, and preventive strategies.

Good performance of syphilis rapid diagnostic test kits among young key populations in Thailand

BACKGROUND

The prevalence of syphilis is increasing among adolescents and young adults (AYAs) globally. Use of syphilis rapid diagnostic treponemal tests (RDTs) may improve test coverage and same-day treatment. This study aims to determine sensitivity and specificity of two syphilis RDTs.

METHODS

A cross-sectional study was conducted in men who have sex with men and transgender women aged 15-24 years attending a sexual health clinic in Bangkok. Syphilis RDTs used were Determine Syphilis TP and Bioline Syphilis 3.0, using whole blood from finger pricks and venipuncture. Treponemal pallidum electrochemiluminescence assay was used as standard reference.

RESULTS

From February to July 2022, 200 AYAs with a mean age 21.1 (SD2.1) years were enrolled, including 50 (25.0%) living with HIV. Prevalence of syphilis was 10.5% (95%CI 6.6-15.6), which was higher among AYAs living with HIV (22.0%) compared with AYAs unaffected by HIV (6.7%). Sensitivities of Determine Syphilis TP and Bioline Syphilis 3.0 were 85.7% (95%CI 63.7-97.0) and 66.7% (95%CI 43.0-85.4), respectively. Specificity of both RDTs was 100% (95%CI 98.0-100.0). Performance of RDTs was similar for both specimens.

CONCLUSIONS

Syphilis RDTs have high sensitivity and specificity in diagnosing syphilis. It should be considered for use in sexual health clinics with high syphilis prevalence to initiate treatment promptly.

Syphilis

Syphilis is a sexually and vertically transmitted bacterial infection caused by the bacterium Treponema pallidum. Its prevalence is high in low-income and middle-income countries, and its incidence has increased in high-income countries in the last few decades among men who have sex with men. Syphilis is a major cause of adverse pregnancy outcomes in low-income and middle-income countries. Clinical features include a primary chancre at the point of inoculation, followed weeks later by the rash of secondary syphilis, a latent period, and in some cases, involvement of the eyes, CNS, and cardiovascular systems. It is diagnosed serologically. A single intramuscular dose of long-acting benzathine penicillin is recommended for people who have had syphilis for less than 1 year and longer courses for people with late latent syphilis. Control strategies include screening and treatment of all pregnant women, and targeted interventions for groups at high risk. Vaccine development, research on antibiotic prophylaxis, and digital messaging as prevention strategies are ongoing.

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.

Advances in Diagnostics of Sexually Transmitted Infections

Sexually transmitted infections (STIs) are caused by various pathogens, many of which have common symptoms. Diagnostic tests are critical to supporting clinical evaluations in making patient management decisions. Molecular diagnostics are the preferred test type when available, especially in asymptomatic patients for many STIs. However, for some infections, serology offers the best insight into infectious status. Clinicians should be aware of the performance characteristics of the available STI diagnostic tests and understand how to use them. Point-of-care tests are helpful to implement rapid and accurate treatment responses, which are particularly helpful in certain at-risk populations.

Improved rapid diagnostic tests to detect syphilis and yaws: a systematic review and meta-analysis

BACKGROUND

Current rapid tests for syphilis and yaws can detect treponemal and non-treponemal antibodies. We aimed to critically appraise the literature for rapid diagnostic tests (RDTs) which can better distinguish an active infection of syphilis or yaws.

METHODS

We conducted a systematic review and meta-analysis, searching five databases between January 2010 and October 2021 (with an update in July 2022). A generalised linear mixed model was used to conduct a bivariate meta-analysis for the pooled sensitivity and specificity. Heterogeneity was assessed using the I² statistic. We used the Quality Assessment of Diagnostic Accuracy Studies (QUADAS) to assess the risk of bias and Grading of Recommendations, Assessment, Development and Evaluations (GRADE) to evaluate the certainty of evidence.

RESULTS

We included 17 studies for meta-analyses. For syphilis, the pooled sensitivity and specificity of the treponemal component were 0.93 (95% CI: 0.86 to 0.97) and 0.98 (95% CI: 0.96 to 0.99), respectively. For the non-treponemal component, the pooled sensitivity and specificity were 0.90 (95% CI: 0.82 to 0.95) and 0.97 (95% CI: 0.92 to 0.99), respectively. For yaws, the pooled sensitivity and specificity of the treponemal component were 0.86 (95% CI: 0.66 to 0.95) and 0.97 (95% CI: 0.94 to 0.99), respectively. For the non-treponemal component, the pooled sensitivity and specificity were 0.80 (95% CI: 0.55 to 0.93) and 0.96 (95% CI: 0.92 to 0.98), respectively.

CONCLUSIONS

RDTs that can differentiate between active and previously treated infections could optimise management by providing same-day treatment and reducing unnecessary treatment.

PROSPERO REGISTRATION NUMBER

CRD42021279587.

Point-of-Care Diagnostics for Diagnosis of Active Syphilis Infection: Needs, Challenges and the Way Forward

Syphilis, a curable sexually transmitted infection, has re-emerged as a global public health threat with an estimated 5.6 million new cases every year. Pregnant women and men who have sex with men are key target populations for syphilis control and prevention programs. Frequent syphilis testing for timely and accurate diagnosis of active infections for appropriate clinical management is a key strategy to effectively prevent disease transmission. However, there are persistent challenges in the diagnostic landscape and service delivery/testing models that hinder global syphilis control efforts. In this commentary, we summarise the current trends and challenges in diagnosis of active syphilis infection and identify the data gaps and key areas for research and development of novel point-of-care diagnostics which could help to overcome the present technological, individual and structural barriers in access to syphilis testing. We present expert opinion on future research which will be required to accelerate the validation and implementation of new point-of-care diagnostics in real-world settings.

Does performance and operational superiority of point-of-care test make it the investigation of choice in confirming syphilis?

Background

According to the World Health Organization, 6 million cases of syphilis occur every year. Serological tests for syphilis form the mainstay of diagnosis for syphilis. We evaluated the performance of point-of-care test (POCT) against other specific treponemal test for confirming the diagnosis of syphilis.

Materials and Methods

Does performance and operational superiority of POCT make it the investigation of choice in confirming syphilis? Retrospectively, data were analyzed of 599 serum samples from Apex Regional sexually transmitted disease centre, Safdarjung Hospital, New Delhi, received for testing by syphilis treponemal assays (both nontreponemal reactive and nonreactive). These samples underwent treponemal testing for syphilis by the Treponema pallidum hemagglutination (TPHA), fluorescent treponemal antibody absorption test (FTA-ABS), and POCT. Performance characteristics (sensitivity, specificity, positive predictive value [PPV], negative predictive value [NPV], and diagnostic accuracy), and operational characteristics of POCT and TPHA were evaluated against the gold standard FTA-ABS.

Results

A total of 599 samples were evaluated, of which 61.76% were positive by FTA-ABS. On analysis, the sensitivity was 91.08% and 91.89%, specificity was 89.08% and 87.34%, PPV was 93.09% and 92.14%, NPV was 86.08% and 86.96%, and diagnostic accuracy was 90.32% and 90.15% for POCT and TPHA, respectively. The lower cost, shorter turnaround time, lesser infrastructure and workforce need, and easy availability make the POCT operationally superior to TPHA.

Conclusion

Owing to its operational superiority and higher specificity POCT can replace TPHA for confirming the diagnosis of Syphilis. POCT are affordable, equipment free, have room temperature storage, and yield result within 15 minutes, enabling same day testing and treatment. It can be used in a resource limited setting, for community setup or even self-testing.

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.

High Lifetime Prevalence of Syphilis in Men Who Have Sex With Men and Transgender Women Versus Low Lifetime Prevalence in Female Sex Workers in Lima, Peru

A study of men who have sex with men, transwomen, and female sex workers in Lima, Peru found that lifetime prevalence of syphilis was substantially lower in female sex workers compared with other groups.

The syphilis epidemic continues to cause substantial morbidity worldwide and is worsening despite ongoing control efforts. Syphilis remains an important public health problem among 3 key populations: men who have sex with men (MSM), transgender women, and female sex workers.

An old disease on the rise: new approaches to syphilis in pregnancy

PURPOSE OF REVIEW

Maternal and congenital syphilis infection is on the rise in the United States and worldwide. Without adequate testing or provider recognition of infection, treatment can be neglected resulting in significant perinatal morbidity and mortality. This review article discusses the epidemiology of T. pallidum, describes novel diagnostic tests, and considers the need to expand therapeutic options.

RECENT FINDINGS

A new chemiluminescence immunoassay for use in the reverse-sequence algorithm is more sensitive and specific in pregnant women than previously noted and is helpful for identifying pregnant women at highest risk for neonatal congenital syphilis. Point-of-care testing may be used to detect early syphilitic disease and provide same-day testing and treatment. Randomized control trials of oral cefixime for treatment of syphilis are paving the way for potential use in pregnant women. Penicillin skin testing, challenge, and desensitization in pregnancy can be done safely.

SUMMARY

Congenital syphilis is a preventable disease and treatable infection in the modern world, but we are still met with challenges in its eradication. We should proceed with advancing efficient laboratory testing, expanding medical therapy, and implementing public health measures to curb the rise of the disease.

The impact of antenatal syphilis point of care testing on pregnancy outcomes: A systematic review

Background

Mother-to-child transmission of syphilis remains a leading cause of neonatal death and stillbirth, disproportionally affecting women in low-resource settings where syphilis prevalence rates are high and testing rates low. Recently developed syphilis point-of-care tests (POCTs) are promising alternatives to conventional laboratory screening in low-resource settings as they do not require a laboratory setting, intensive technical training and yield results in 10–15 minutes thereby enabling both diagnosis and treatment in a single visit. Aim of this review was to provide clarity on the benefits of different POCTs and assess whether the implementation of syphilis POCTs is associated with decreased numbers of syphilis-related adverse pregnancy outcomes.

Methods

Following the PRISMA guidelines, three electronic databases (PubMed, Medline (Ovid), Cochrane) were systematically searched for intervention studies and cost-effectiveness analyses investigating the association between antenatal syphilis POCT and pregnancy outcomes such as congenital syphilis, low birth weight, prematurity, miscarriage, stillbirth as well as perinatal, fetal or infant death.

Results

Nine out of 278 initially identified articles were included, consisting of two clinical studies and seven modelling studies. Studies compared the effect on pregnancy outcomes of treponemal POCT, non-treponemal POCT and dual POCT to laboratory screening and no screening program. Based on the clinical studies, significantly higher testing and treatment rates, as well as a significant reduction (93%) in adverse pregnancy outcomes was reported for treponemal POCT compared to laboratory screening. Compared to no screening and laboratory screening, modelling studies assumed higher treatment rates for POCT and predicted the most prevented adverse pregnancy outcomes for treponemal POCT, followed by a dual treponemal and non-treponemal POCT strategy.

Conclusion

Implementation of treponemal POCT in low-resource settings increases syphilis testing and treatment rates and prevents the most syphilis-related adverse pregnancy outcomes compared to no screening, laboratory screening, non-treponemal POCT and dual POCT. Regarding the benefits of dual POCT, more research is needed. Overall, this review provides evidence on the contribution of treponemal POCT to healthier pregnancies and contributes greater clarity on the impact of diverse diagnostic methods available for the detection of syphilis.

Nonviral sexually transmitted infections in pregnancy: current controversies and new challenges

PURPOSE OF REVIEW

This review provides an update of nonviral, curable sexually transmitted infections (STIs) in pregnancy and summarizes our understanding of the current issues and controversies surrounding risk factors, screening, and treatment of STIs in pregnancy primarily in high-income countries (using the United States and the United Kingdom as examples). The infections covered in this review are syphilis, gonorrhea, chlamydia, trichomoniasis, and Mycoplasma genitalium infections.

RECENT FINDINGS

Overall, limited modern data is available to update researchers and clinicians on the epidemiology and care of STIs in pregnancy. Though common risk factors can be identified among these STIs, like socioeconomic status and inadequate antenatal care, specific screening and treatment challenges vary by geography and pathogen. Wherever available, surveillance data and research evidence are often limited to nonpregnant patients, leading to imperfect pregnancy-specific risk estimates and obstetric lags in the development and adoption of new guidelines. We have identified three areas of opportunity that may enhance the effectiveness of current approaches and inform new ones: improved data collection and evidence-based screening practices; prompt and comprehensive therapy, including partner services, and evaluations of new treatment modalities; and equitable antenatal and sexual healthcare for all pregnant persons and their partners.

SUMMARY

These findings highlight the need to revisit standards of screening and management of STIs in pregnancy in high-income countries.

Point-of-Care Testing for Sexually Transmitted Infections: A Review of Recent Developments

CONTEXT.—

Sexually transmitted infections (STIs) are among the most common communicable diseases globally and are associated with significant morbidity and mortality worldwide. Point-of-care tests have the potential to revolutionize the prevention and control of STIs by enabling rapid diagnosis and early treatment of infections, thus interrupting transmission and preventing the sequelae of untreated infections. Currently, there are several point-of-care (POC) tests available for the diagnosis of Treponema pallidum, Chlamydia trachomatis, Neisseria gonorrhoeae, and Trichomonas vaginalis infections, although these tests differ with regard to their performance, turnaround time, and cost.

OBJECTIVE.—

To provide an updated review of the POC tests available and under development for the diagnosis of T pallidum, C trachomatis, N gonorrhoeae, and T vaginalis infections, to discuss the context for which these tests might be used, and to highlight future directions for test development.

DATA SOURCES.—

We reviewed the literature pertaining to the recent development and performance evaluations of POC tests for the diagnosis of syphilis, chlamydia, gonorrhea, and trichomonas.

CONCLUSIONS.—

Recently, there has been rapid development of new POC tests for STIs. Although there are inexpensive, rapid, and accurate POC tests available for syphilis, there are few such tests available for the diagnosis of chlamydia, gonorrhea, or trichomonas, and currently none with the ability to detect antimicrobial resistance in N gonorrhoeae. Research evaluating implementation strategies for the currently available tests and the development of additional POC tests that are rapid, accurate, and affordable are urgently needed to address the rising number of STIs worldwide.

Nanotechnology in reproductive medicine: Opportunities for clinical translation

In recent years, nanotechnology has revolutionized global healthcare and has been predicted to exert a remarkable effect on clinical medicine. In this context, the clinical use of nanomaterials for cancer diagnosis, fertility preservation, and the management of infertility and other pathologies linked to pubertal development, menopause, sexually transmitted infections, and HIV (human immunodeficiency virus) has substantial promise to fill the existing lacunae in reproductive healthcare. Of late, a number of clinical trials involving the use of nanoparticles for the early detection of reproductive tract infections and cancers, targeted drug delivery, and cellular therapeutics have been conducted. However, most of these trials of nanoengineering are still at a nascent stage, and better synergy between pharmaceutics, chemistry, and cutting-edge molecular sciences is needed for effective translation of these interventions from bench to bedside. To bridge the gap between translational outcome and product development, strategic partnerships with the insight and ability to anticipate challenges, as well as an in-depth understanding of the molecular pathways involved, are highly essential. Such amalgamations would overcome the regulatory gauntlet and technical hurdles, thereby facilitating the effective clinical translation of these nano-based tools and technologies. The present review comprehensively focuses on emerging applications of nanotechnology, which holds enormous promise for improved therapeutics and early diagnosis of various human reproductive tract diseases and conditions.

[Rapid diagnosis of sexually transmitted infections : Joint statement of DSTIG, RKI, and PEI, as well as the reference centers for HIV, HBV, and HCV and consulting laboratories for Chlamydia, gonococci, and Treponema pallidum]

In February 2019, the fourth expert meeting on rapid diagnostic tests (RDTs) for sexually transmitted infections (STI) was held at the Robert Koch Institute (RKI) in Berlin. Novel technical developments and new aspects of RDT applications were discussed by representatives from the German STI Society (DSTIG); RKI; the Paul Ehrlich Institute; national reference centers for HIV, HBV, and HCV; and reference laboratories for Chlamydia, gonococci, and Treponema pallidum.As a result of this meeting, we present a revision of the joint statement on STI diagnostics with RDTs from 2017. The Regulation (EU) 2017/746 of the European Parliament and of the Council on in vitro diagnostic medical devices became effective in May 2017 and includes more stringent regulatory requirements for RDTs, mainly concerning conformity of manufacturing processes and performance characteristics of class D in vitro diagnostics (detection of HIV, HBV, HCV, and T. pallidum). Some RDTs for HIV, HCV, and T. pallidum have been evaluated in clinical studies and/or were WHO prequalified and may be used in low-threshold services. Among them are some HIV RDTs available and approved for self-testing. In addition, some HBV RDTs based on detection of HBs antigen (HBsAg) received WHO prequalification. However, false negative results may occur in samples with low HBsAg levels, as for instance in HIV-coinfected patients receiving antiretroviral therapy. For Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG), antigen-based RDTs still do not allow reliable detection of infection. Only PCR-based CT/NG RDTs possess sufficient diagnostic accuracy to be used as point-of-care tests. Rapid PCR tests for NG, however, do not provide any information about antimicrobial resistance.

Point-of-Care Testing in Microbiology: A Mechanism for Improving Patient Outcomes

BACKGROUND

Increasingly, demands for improved health and quality of life conflict with the realities of delivering healthcare in an environment of higher expenditures, adherence to test utilization, and patient-centered experience. Patient-centered care is commonly identified as a goal of healthcare delivery, and yet healthcare systems struggle with delivery of care to patients, often failing to identify the seriously ill and capitalize on the predictive qualities of diagnostic testing. Point-of-care (POC) testing provides access to rapid diagnosis and predictive value key to realizing patient outcomes. An evaluation of cost-effective models and the clinical impact of POC testing for clinical microbiology is needed.

CONTENT

Accurate and rapid diagnostics have the potential to affect healthcare decisions to a degree well out of proportion to their cost. Contemporary healthcare models increasingly view POC testing as a mechanism for efficient deployment of healthcare. POC testing can deliver rapid diagnosis in environments where testing results can be used to direct management during patient visits and in areas where centralized laboratory testing may limit access to care. Nucleic acid assays, designed for POC testing, can match, or exceed, the sensitivity of conventional laboratory-based testing, eliminating the need for confirmation testing. Here, the goals of POC testing for microbiology, applications, and technologies, as well as outcomes and value propositions, are discussed.

SUMMARY

The combination of rapid reporting, an increasing array of organisms capable of causing disease, actionable resulting, and improved patient outcomes is key in the evolution of POC testing in clinical microbiology.

Improving the coverage and accuracy of syphilis testing: The development of a novel rapid, point-of-care test for confirmatory testing of active syphilis infection and its early evaluation in China and South Africa

BACKGROUND

Current point-of-care tests (POCT) for syphilis, based on the detection of Treponema pallidum (TP) total antibodies, have limited capacity in distinguishing between active and past/treated syphilis. We report the development and early evaluation of a new prototype POCT based on the detection of TP-IgA antibodies, a novel biomarker for active syphilis.

METHODS

The TP-IgA POCT (index test) was developed in response to the World Health Organisation (WHO) target product profile (TPP) for a POCT for confirmatory syphilis testing. Two sub-studies were conducted consecutively using 458 pre-characterised stored plasma samples in China (sub-study one, addressing the criteria for the WHO TPP), and 503 venous blood samples collected from pregnant/postpartum women in South Africa (sub-study two, addressing potential clinical utility). Performance of the index test was assessed against standard laboratory-based serology using a combination of treponemal (TPHA) and non-treponemal (rapid plasma reagin [RPR]) tests.

FINDINGS

In sub-study one, the index test demonstrated 96·1% (95%CI=91·7%-98·5%) sensitivity and 84·7% (95%CI=80·15-88·6%) specificity for identification of active syphilis (TPHA positive, RPR positive). It correctly identified 71% (107/150) samples of past-treated syphilis (TPHA positive, RPR negative). In sub-study two, the index test achieved 100% (95%CI=59%-100%) sensitivity for active syphilis and correctly identified all nine women with past syphilis.

INTERPRETATION

The TP-IgA POCT has met the WHO TPP for a POCT for diagnosis of active syphilis and demonstrated its potential utility in a clinical setting. Future studies are warranted to evaluate field performance of the final manufactured test.

FUNDING

Saving Lives at Birth: Grand Challenge for Development, Thrasher Research Fund, and the Victorian Government Operational Infrastructure Scheme.

Evaluation of a Rapid Syphilis Test in an Emergency Department Setting in Detroit, Michigan

BACKGROUND

Syphilis transmission can be prevented by prompt diagnosis and treatment of primary and secondary infection. We evaluated the performance of a point-of-care rapid syphilis treponemal (RST) test in an emergency department (ED) setting.

METHODS

Between June 2015 and April 2016, men aged 18 to 34 years seeking services in a Detroit ED, and with no history of syphilis, were screened for syphilis with the RST test, rapid plasma reagin (RPR) test, and Treponema pallidum particle agglutination assay (TP-PA). A positive reference standard was both a reactive RPR and a reactive TP-PA. We compared test results in self-reported men who have sex with men (MSM) to non-MSM.

RESULTS

Among 965 participants, 10.9% of RST tests were reactive in MSM and only 1.5% in non-MSM (P < 0.001). Sensitivity of the RST test was 76.9% and specificity was 99.0% (positive predictive value, 50.0%) compared with the positive reference standard. Three discordant specimens found negative with the RST test but positive with the reference standard had an RPR titer of 1:1, compared with 10 specimens with concordant positive results that had a median RPR titer of 1:16. The RST sensitivity was 50.0% (positive predictive value, 68.4%) compared to the TP-PA test alone. Among men seeking care in an ED, the RST detected 76.9% of participants with a reactive RPR and TP-PA.

CONCLUSIONS

The RST test detected all of the participants with an RPR titer ≥1:2 but less than 20% of participants with a positive TP-PA and negative RPR. The RST test was useful to detect a high proportion of participants with an active syphilis in an urban ED.

Performance of the Syphilis Health Check in Clinic and Laboratory-Based Settings

A study to evaluate clinical and laboratory performance of the Syphilis Health Check, found improved sensitivity when testing with whole blood compared to serum, in detecting likely active syphilis.

Background

In this study, we evaluate the performance of the Syphilis Health Check (SHC) in clinical and laboratory settings using fingerstick whole blood and serum.

Methods

Fingerstick whole blood and serum specimens from adult patients (n = 562) without prior syphilis history presenting at 2 county health department STD clinics in North Carolina were tested. Fingerstick specimens were tested with the SHC in clinic, and serum specimens were tested at the North Carolina State Laboratory of Public Health with: (1) qualitative rapid plasma reagin, (2) treponemal EIA, and (3) SHC. Sensitivity and specificity were calculated with 95% confidence intervals.

Results

The fingerstick whole blood had a sensitivity of 100% (7 of 7) and specificity of 95.7% (531 of 555), compared with consensus reference testing (CRT) (rapid plasma reagin and EIA reactive), but a sensitivity of 50% (8 of 16), and specificity of 95.9% (523 of 546), when compared with the treponemal EIA. Both laboratory-based SHC on serum and whole-blood SHC performed similarly, compared with CRT, and the treponemal EIA alone. Twenty-four specimens SHC reactive on whole blood were nonreactive by CRT. In 8 of these 24 cases, STD clinic staff reported difficulty reading the test line for the SHC. Of the fingerstick whole-blood SHC reactive specimens, only 14 of 31 were also serum SHC reactive.

Conclusions

The SHC on whole blood appears to be sensitive at detecting patients likely to have syphilis and could be an option for testing among high-risk populations. However, given challenges in interpreting SHC test results, adequate training of persons performing testing and ongoing quality assurance measures are key.

Integrating HIV, syphilis, malaria and anaemia point-of-care testing (POCT) for antenatal care at dispensaries in western Kenya: discrete-event simulation modelling of operational impact

BACKGROUND

Despite WHO advocating for an integrated approach to antenatal care (ANC), testing coverage for conditions other than HIV remains low and women are referred to distant laboratories for testing. Using point-of-care tests (POCTs) at peripheral dispensaries could improve access to testing and timely treatment. However, the effect of providing additional services on nurse workload and client wait times are unknown. We use discrete-event simulation (DES) modelling to understand the effect of providing four point-of-care tests for ANC on nurse utilization and wait times for women seeking maternal and child health (MCH) services.

METHODS

We collected detailed time-motion data over 20 days from one high volume dispensary in western Kenya during the 8-month implementation period (2014-2015) of the intervention. We constructed a simulation model using empirical arrival distributions, activity durations and client pathways of women seeking MCH services. We removed the intervention from the model to obtain wait times, length-of-stay and nurse utilization rates for the baseline scenario where only HIV testing was offered for ANC. Additionally, we modelled a scenario where nurse consultations were set to have minimum durations for sufficient delivery of all WHO-recommended services.

RESULTS

A total of 183 women visited the dispensary for MCH services and 14 of these women received point-of-care testing (POCT). The mean difference in total waiting time was 2 min (95%CI: < 1-4 min, p = 0.026) for MCH women when integrated POCT was given, and 9 min (95%CI: 4-14 min, p < 0.001) when integrated POCT with adequate ANC consult times was given compared to the baseline scenario. Mean length-of-stay increased by 2 min (95%CI: < 1-4 min, p = 0.015) with integrated POCT and by 16 min (95%CI: 10-21 min, p < 0.001) with integrated POCT and adequate consult times compared to the baseline scenario. The two nurses' overall daily utilization in the scenario with sufficient minimum consult durations were 72 and 75%.

CONCLUSION

The intervention had a modest overall impact on wait times and length-of-stay for women seeking MCH services while ensuring pregnant women received essential diagnostic testing. Nurse utilization rates fluctuated among days: nurses experienced spikes in workload on some days but were under-utilized on the majority of days. Overall, our model suggests there was sufficient time to deliver all WHO's required ANC activities and offer integrated testing for ANC first and re-visits with the current number of healthcare staff. Further investigations on improving healthcare worker, availability, performance and quality of care are needed. Delivering four point-of-care tests together for ANC at dispensary level would be a low burden strategy to improve ANC.

Evaluation of Rapid Syphilis Testing Using the Syphilis Health Check in Florida, 2015-2016

The Syphilis Health Check (SHC) had low estimated specificity (91.5%) in one Florida county. We investigated use of SHC by a range of Florida publicly-funded programs between 2015 and 2016 to estimate specificity, positive predictive value (PPV), field staff acceptance, and impacts on programmatic outcomes. All reported SHC results were extracted from routinely collected program data. Field staff were surveyed about SHC's utility. Analyses investigated differences between SHC and traditional syphilis testing outcomes. Of 3,630 SHC results reported, 442 were reactive; 92 (20.8%) had prior diagnoses of syphilis; 7 (1.6%) had no further testing. Of the remaining 343; 158 (46.0%) were confirmed cases, 168 (49.0%) were considered false-positive, and 17 (5.0%) were not cases but not clearly false-positive. Estimated specificity of SHC was 95.0%. Overall, 48.5% of positives became confirmed cases (PPV). PPV varied according to prevalence of syphilis in populations tested. Staff (90%) thought SHC helped identify new cases but expressed concern regarding discordance between reactive SHC and lab-based testing. Programmatic outcomes assessment showed shorter time to treatment and increased numbers of partners tested for the SHC group; these enhanced outcomes may better mitigate the spread of syphilis compared to traditional syphilis testing alone, but more research is needed.

Diagnosing sexually transmitted infections in resource-constrained settings: challenges and ways forward

INTRODUCTION

Sexually transmitted infections (STIs) remain prevalent and are increasing in several populations. Appropriate STI diagnosis is crucial to prevent the transmission and sequelae of untreated infection. We reviewed the diagnostic accuracy of syndromic case management and existing point-of-care tests (POCTs), including those in the pipeline, to diagnose STIs in resource-constrained settings.

METHODS

We prioritized updating the systematic review and meta-analysis of the diagnostic accuracy of vaginal discharge from 2001 to 2015 to include studies until 2018. We calculated the absolute effects of different vaginal flowcharts and the diagnostic performance of POCTs on important outcomes. We searched the peer-reviewed literature for previously conducted systematic reviews and articles from 1990 to 2018 on the diagnostic accuracy of syndromic management of vaginal and urethral discharge, genital ulcer and anorectal infections. We conducted literature reviews from 2000 to 2018 on the existing POCTs and those in the pipeline.

RESULTS AND DISCUSSIONS

The diagnostic accuracy of urethral discharge and genital ulcer disease syndromes is relatively adequate. Asymptomatic Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) infections limit the use of vaginal discharge and anorectal syndromes. The pooled diagnostic accuracy of vaginal syndromic case management for CT/NG is low, resulting in high numbers of overtreatment and missed treatment. The absolute effect of POCTs was reduced overtreatment and missed treatment. Findings of the reviews on syndromic case management underscored the need for low-cost and accurate POCTs for the identification, first, of CT/NG, and, second, of Mycoplasma genitalium (MG) and Trichomonas vaginalis (TV) and NG and MG resistance/susceptibility testing. Near-patient POCT molecular assays for CT/NG/TV are commercially available. The prices of these POCTs remain the barrier for uptake in resource-constrained settings. This is driving the development of lower cost solutions.

CONCLUSIONS

The WHO syndromic case management guidelines should be updated to raise the quality of STI management through the integration of laboratory tests. STI screening strategies are needed to address asymptomatic STIs. POCTs that are accurate, rapid, simple and affordable are urgently needed in resource-constrained settings to support the uptake of aetiological diagnosis and treatment.

Sexually acquired syphilis: Laboratory diagnosis, management, and prevention

The methods used for the laboratory diagnosis of syphilis include direct detection of Treponema pallidum subspecies pallidum and serologic testing. Serologic testing relies on both nontreponemal and treponemal tests. In newly developed reverse-sequence screening algorithms, treponemal tests are performed before nontreponemal tests. The management of syphilis requires appropriate staging, treatment, and follow-up of patients along with the prompt reporting of infections to public health authorities to assist with prevention and control efforts. Benzathine penicillin G remains the treatment of choice for all stages of syphilis. Screening of populations at higher risk for syphilis is recommended by the US Centers for Disease Control and Prevention, the US Preventive Services Task Force, and the World Health Organization. The second article in this continuing medical education series reviews the testing for and the management of sexually acquired syphilis.

Antibiotic treatment for newborns with congenital syphilis

BACKGROUND

Congenital syphilis continues to be a substantial public health problem in many parts of the world. Since the first use of penicillin for the treatment of syphilis in 1943, which was a notable early success, it has remained the preferred and standard treatment including for congenital syphilis. However, the treatment of congenital syphilis is largely based on clinical experience and there is extremely limited evidence on the optimal dose or duration of administration of penicillin or the use of other antibiotics.

OBJECTIVES

To assess the effectiveness and safety of antibiotic treatment for newborns with confirmed, highly probable and possible congenital syphilis.

SEARCH METHODS

We searched the Cochrane STI Group Specialized Register, CENTRAL, MEDLINE, Embase, LILACS, WHO ICTRP, ClinicalTrials.gov and Web of Science to 23 May 2018. We also handsearched conference proceedings, contacted trial authors and reviewed the reference lists of retrieved studies.

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing antibiotic treatment (any concentration, frequency, duration and route) with no intervention or any other antibiotic treatment for neonates with confirmed, highly probable or possible congenital syphilis.

DATA COLLECTION AND ANALYSIS

All review authors independently assessed trials for inclusion, extracted data and assessed the risk of bias in the included studies. We resolved any disagreements through consensus. We assessed the quality of the evidence using the GRADE approach.

MAIN RESULTS

Two RCTs (191 participants) met our inclusion criteria and none of these trials was funded by the industry. One trial (22 participants) compared benzathine penicillin with no intervention for infants with possible congenital syphilis. Low-quality evidence suggested that benzathine penicillin administration may not have decreased the rate of neonatal death due to any cause (risk ratio (RR) 0.83, 95% confidence interval (CI) 0.06 to 11.70), and showed a possible reduction into the proportion of neonates with clinical manifestations of congenital syphilis (RR 0.12, 95% CI 0.01 to 2.09). Penicillin administration increased the serological cure at the third month (RR 2.13, 95% CI 1.06 to 4.27). These results should be taken with caution, because the trial was stopped early because there were four cases with clinical congenital syphilis in the no treatment group and none in the treatment group. Interim analysis suggested this difference was significant. This study did not report neonatal death due to congenital syphilis or the frequency of serious or minor adverse events after therapy. We downgraded the quality of evidence because of imprecision and risk of bias.One trial (169 participants) compared benzathine penicillin versus procaine benzylpenicillin. High- and moderate-quality evidence suggested that there were probably no differences between benzathine penicillin and procaine benzylpenicillin for the outcomes: absence of clinical manifestations of congenital syphilis (RR 1.00, 95% CI 0.97 to 1.03) and serological cure (RR 1.00, 95% CI 0.97 to 1.03). There were no cases of neonatal death due congenital syphilis; all 152 babies who followed up survived. This study did not report on the frequency of serious or minor adverse events after therapy. We downgraded the quality of evidence because of serious risk of bias.

AUTHORS' CONCLUSIONS

At present, the evidence on the effectiveness and safety of antibiotic treatment for newborns with confirmed, highly probable or possible congenital syphilis is sparse, implying that we are uncertain about the estimated effect. One trial compared benzathine penicillin with no intervention for infants with possible congenital syphilis. Low-quality evidence suggested penicillin administration possibly reduce the proportion of neonates with clinical manifestations of congenital syphilis, penicillin administration increased the serological cure at the third month. These findings support the clinical use of penicillin in neonates with confirmed, highly probable or possible congenital syphilis. High- and moderate-quality evidence suggests that there are probably no differences between benzathine penicillin and procaine benzylpenicillin administration for the outcomes of absence of clinical manifestations of syphilis or serological cure.

Integrated point-of-care testing (POCT) for HIV, syphilis, malaria and anaemia at antenatal facilities in western Kenya: a qualitative study exploring end-users' perspectives of appropriateness, acceptability and feasibility

Background

HIV, syphilis, malaria and anaemia are leading preventable causes of adverse pregnancy outcomes in sub-Saharan Africa yet testing coverage for conditions other than HIV is low. Availing point-of-care tests (POCTs) at rural antenatal health facilities (dispensaries) has the potential to improve access and timely treatment. Fundamental to the adoption of and adherence to new diagnostic approaches are healthcare workers’ and pregnant women’s (end-users) buy-in. A qualitative approach was used to capture end-users’ experiences of using POCTs for HIV, syphilis, malaria and anaemia to assess the appropriateness, acceptability and feasibility of integrated testing for ANC.

Methods

Seven dispensaries were purposively selected to implement integrated point-of-care testing for eight months in western Kenya. Semi-structured interviews were conducted with 18 healthcare workers (14 nurses, one clinical officer, two HIV testing counsellors, and one laboratory technician) who were trained, had experience doing integrated point-of-care testing, and were still working at the facilities 8–12 months after the intervention began. The interviews explored acceptability and relevance of POCTs to ANC, challenges with testing, training and supervision, and healthcare workers’ perspectives of client experiences. Twelve focus group discussions with 118 pregnant women who had attended a first ANC visit at the study facilities during the intervention were conducted to explore their knowledge of HIV, syphilis, malaria, and anaemia, experience of ANC point-of-care testing services, treatments received, relationships with healthcare workers, and experience of talking to partners about HIV and syphilis results.

Results

Healthcare workers reported that they enjoyed gaining new skills, were enthusiastic about using POCTs, and found them easy to use and appropriate to their practice. Initial concerns that performing additional testing would increase their workload in an already strained environment were resolved with experience and proficiency with the testing procedures. However, despite having the diagnostic tools, general health system challenges such as high client to healthcare worker volume ratio, stock-outs and poor working conditions challenged the delivery of adequate counselling and management of the four conditions. Pregnant women appreciated POCTs, but reported poor healthcare worker attitudes, drug stock-outs, and fear of HIV disclosure to their partners as shortcomings to their ANC experience in general.

Conclusion

This study provides insights on the acceptability, appropriateness, and feasibility of integrating POCTs into ANC services among end-users. While the innovation was desired and perceived as beneficial, future scale-up efforts would need to address health system weaknesses if integrated testing and subsequent effective management of the four conditions are to be achieved.

Electronic supplementary material

The online version of this article (10.1186/s12913-018-3844-9) contains supplementary material, which is available to authorized users.

REASSURED diagnostics to inform disease control strategies, strengthen health systems and improve patient outcomes

Lack of access to quality diagnostics remains a major contributor to health burden in resource-limited settings. It has been more than 10 years since ASSURED (affordable, sensitive, specific, user-friendly, rapid, equipment-free, delivered) was coined to describe the ideal test to meet the needs of the developing world. Since its initial publication, technological innovations have led to the development of diagnostics that address the ASSURED criteria, but challenges remain. From this perspective, we assess factors contributing to the success and failure of ASSURED diagnostics, lessons learnt in the implementation of ASSURED tests over the past decade, and highlight additional conditions that should be considered in addressing point-of-care needs. With rapid advances in digital technology and mobile health (m-health), future diagnostics should incorporate these elements to give us REASSURED diagnostic systems that can inform disease control strategies in real-time, strengthen the efficiency of health care systems and improve patient outcomes.

A high burden of asymptomatic genital tract infections undermines the syndromic management approach among adolescents and young adults in South Africa: implications for HIV prevention efforts

BACKGROUND

Youth in southern Africa, particularly adolescent girls and young women, are a key population for HIV prevention interventions. Untreated genital tract infections (GTIs) increase both HIV transmission and acquisition risks. South African GTI treatment guidelines employ syndromic management, which relies on individuals to report GTI signs and symptoms. Syndromic management may, however, underestimate cases, particularly among youth. We compared genital tract infection (GTI) prevalence by symptom-based and laboratory assessment among sexually-experienced youth in South Africa, overall and stratified by sex.

METHODS

Interviewer-administered surveys assessed socio-demographics, behaviors, and GTI symptoms among 352 youth (16-24 yrs., HIV-negative or unknown HIV status at enrollment) enrolled in community-based cohorts in Durban and Soweto (2014-2016). Laboratory tests assessed HIV, Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG), Mycoplasma genitalium (MG), Trichomonas vaginalis (TV) infections and, among females, bacterial vaginosis (BV) and Candida species. Youth with genital ulcers were tested for HSV-2 and syphilis. We assessed sensitivity (and specificity) of symptom-based reporting in identifying laboratory-confirmed GTIs.

RESULTS

At baseline, 16.2% of females (32/198) and < 1% (1/154) of males reported ≥1 GTI symptom. However, laboratory tests identified ≥1 GTI in 70.2% and 10.4%, respectively. Female CT prevalence was 18.2%, NG 7.1%, MG 9.6%, TV 8.1%, and 5.1% were newly diagnosed with HIV. BV prevalence was 53.0% and candidiasis 9.6%. One female case of herpes was identified (0 syphilis). Male CT prevalence was 7.8%, NG 1.3%, MG 3.3%, TV < 1%, and 2.0% were newly diagnosed with HIV. Overall, 77.8% of females and 100% of males with laboratory-diagnosed GTIs reported no symptoms or were asymptomatic. Sensitivity (and specificity) of symptom-based reporting was 14% (97%) among females and 0% (99%) among males.

CONCLUSION

A high prevalence of asymptomatic GTIs and very poor sensitivity of symptom-based reporting undermines the applicability of syndromic GTI management, thus compromising GTI control and HIV prevention efforts among youth. Syndromic GTI management does not meet the sexual health needs of young people. Policy changes incorporating innovations in GTI diagnostic testing are needed to reduce GTIs and HIV-associated risks among youth.

Laboratory Evaluation of a Commercially Available Rapid Syphilis Test

Serological diagnosis of syphilis depends on assays that detect treponemal and nontreponemal antibodies. Laboratory certification and trained personnel are needed to perform most of these tests, while high costs and long turnaround time can hinder treatment initiation or linkage to care. A rapid treponemal syphilis test (RST) that is simple to perform, accessible, and inexpensive would be ideal. The Syphilis Health Check (SHC) assay is the only Food and Drug Administration (FDA)-cleared and Clinical Laboratory Improvement Amendments (CLIA)-waived RST in the United States. In this study, 1,406 archived human serum samples were tested using SHC and traditional treponemal and nontreponemal assays. Rapid test results were compared with treponemal data alone and with a laboratory test panel consensus defined as being reactive by both treponemal and nontreponemal assays for a given specimen, or nonreactive by both types of assays. The sensitivity and specificity of the SHC assay compared with treponemal tests alone were 88.7% (95% confidence interval [CI], 86.2 to 90.0%) and 93.1% (95% CI, 90.0 to 94.9%), respectively, while comparison with the laboratory test panel consensus showed 95.7% (95% CI, 93.6 to 97.2%) sensitivity and 93.2% (95% CI, 91.0 to 95.1%) specificity. The data were further stratified based on age, sex, pregnancy, and HIV status. The sensitivity and specificity of the SHC assay ranged from 66.7% (95% CI, 46.0 to 83.5%) to 91.7% (95% CI, 87.7 to 94.7%) and 88% (95% CI, 68.8 to 97.5%) to 100% (95% CI, 47.8 to 100%), respectively, across groups compared to traditional treponemal assays, generally increasing for all groups except the HIV-positive (HIV+) population when factoring in the laboratory test panel consensus. These data contribute to current knowledge of the SHC assay performance for distinct populations and may guide use in various settings.

Integrated point-of-care testing (POCT) of HIV, syphilis, malaria and anaemia in antenatal clinics in western Kenya: A longitudinal implementation study

Background

In sub-Saharan Africa, HIV, syphilis, malaria and anaemia are leading preventable causes of adverse pregnancy outcomes. In Kenya, policy states women should be tested for all four conditions (malaria only if febrile) at first antenatal care (ANC) visit. In practice, while HIV screening is conducted, coverage of screening for the others is suboptimal and early pregnancy management of illnesses is compromised. This is particularly evident at rural dispensaries that lack laboratories and have parallel programmes for HIV, reproductive health and malaria, resulting in fractured and inadequate care for women.

Methods

A longitudinal eight-month implementation study integrating point-of-care diagnostic tests for the four conditions into routine ANC was conducted in seven purposively selected dispensaries in western Kenya. Testing proficiency of healthcare workers was observed at initial training and at three monthly intervals thereafter. Adoption of testing was compared using ANC register data 8.5 months before and eight months during the intervention. Fidelity to clinical management guidelines was determined by client exit interviews with success defined as ≥90% adherence.

Findings

For first ANC visits at baseline (n = 529), testing rates were unavailable for malaria, low for syphilis (4.3%) and anaemia (27.8%), and near universal for HIV (99%). During intervention, over 95% of first attendees (n = 586) completed four tests and of those tested positive, 70.6% received penicillin or erythromycin for syphilis, 65.5% and 48.3% received cotrimoxazole and antiretrovirals respectively for HIV, and 76.4% received artemether/lumefantrine, quinine or dihydroartemisinin–piperaquine correctly for malaria. Iron and folic supplements were given to nearly 90% of women but often at incorrect doses.

Conclusions

Integrating point-of-care testing into ANC at dispensaries with established HIV testing programmes resulted in a significant increase in testing rates, without disturbing HIV testing rates. While more cases were detected and treated, treatment fidelity still requires strengthening and an integrated monitoring and evaluation system needs to be established.

Evaluation of the utility of a rapid test for syphilis at a sexually transmitted disease clinic in Buenos Aires, Argentina

Even though syphilis can be easily diagnosed by simple and low-cost laboratory methods, it continues to be an important health problem. Rapid tests (RT) for the detection of treponemal antibodies can facilitate earlier diagnosis, access to treatment and linkage to care. The aim of this study was to analyse the usefulness of the incorporation of a RT in the detection of patients infected with T. pallidum in a sexually-transmitted disease (STD) clinic. Between March and December 2015, a syphilis RT was offered to patients who spontaneously attended the clinic. Conventional serology testing was additionally indicated to every participant. The RT for syphilis was offered to 1887 patients, of whom 31.1% agreed to get tested. VDRL test was performed in 84.0% of patients that were also tested with syphilis RT, with a significantly higher frequency observed among participants with reactive RT (94.3% vs. 79.8%, p < 0.001). These results showed that 33.7% of the participants were reactive for the RT and 27.0% were reactive for the VDRL test. Both tests were reactive in 24.9% and non-reactive in 64.3%. A high prevalence of active syphilis was detected in patients attending the clinic. The use of a syphilis RT had a positive impact, which in combination with the VDRL test increased the number of patients that were effectively diagnosed.

Expanding syphilis testing: a scoping review of syphilis testing interventions among key populations

INTRODUCTION

Syphilis is an important sexually transmitted infection (STI). Despite inexpensive and effective treatment, few key populations receive syphilis testing. Innovative strategies are needed to increase syphilis testing among key populations. Areas covered: This scoping review focused on strategies to increase syphilis testing in key populations (men who have sex with men (MSM), sex workers, people who use drugs, transgender people, and incarcerated individuals). Expert commentary: We identified many promising syphilis testing strategies, particularly among MSM. These innovations are separated into diagnostic, clinic-based, and non-clinic based strategies. In terms of diagnostics, self-testing, dried blood spots, and point-of-care testing can decentralize syphilis testing. Effective syphilis self-testing pilots suggest the need for further attention and research. In terms of clinic-based strategies, modifying default clinical procedures can nudge physicians to more frequently recommend syphilis testing. In terms of non-clinic based strategies, venue-based screening (e.g. in correctional facilities, drug rehabilitation centres) and mobile testing units have been successfully implemented in a variety of settings. Integration of syphilis with HIV testing may facilitate implementation in settings where individuals have increased sexual risk. There is a strong need for further syphilis testing research and programs.

Advancing prevention of sexually transmitted infections through point-of-care testing: target product profiles and landscape analysis

OBJECTIVES

Advancing the field of point-of-care testing (POCT) for STIs can rapidly and substantially improve STI control and prevention by providing targeted, essential STI services (case detection and screening). POCT enables definitive diagnosis and appropriate treatment in a single visit and home and community-based testing.

METHODS

Since 2014, the WHO Department of Reproductive Health and Research, in collaboration with technical partners, has completed four landscape analyses of promising diagnostics for use at or near the point of patient care to detect syphilis, Neisseria gonorrhoeae, Chlamydia trachomatis, Trichomonas vaginalis and the human papillomavirus. The analyses comprised a literature review and interviews. Two International Technical Consultations on STI POCTs (2014 and 2015) resulted in the development of target product profiles (TPP). Experts in STI microbiology, laboratory diagnostics, clinical management, public health and epidemiology participated in the consultations with representation from all WHO regions.

RESULTS

The landscape analysis identified diagnostic tests that are either available on the market, to be released in the near future or in the pipeline. The TPPs specify 28 analytical and operational characteristics of POCTs for use in different populations for surveillance, screening and case management. None of the tests that were identified in the landscape analysis met all of the targets of the TPPs.

CONCLUSION

More efforts of the global health community are needed to accelerate access to affordable quality-assured STI POCTs, particularly in low- and middle-income countries, by supporting the development of new diagnostic platforms as well as strengthening the validation and implementation of existing diagnostics according to internationally endorsed standards and the best available evidence.

Rapid diagnostic test for antenatal syphilis screening in low-income and middle-income countries: a systematic review and meta-analysis

OBJECTIVES

To undertake a systematic review and meta-analysis to evaluate the test performance including sensitivity and specificity of rapid immunochromatographic syphilis (ICS) point-of-care (POC) tests at antenatal clinics compared with reference standard tests (non-treponemal (TP) and TP tests) for active syphilis in pregnant women.

METHODS

Five electronic databases were searched (PubMed, EMBASE, CRD, Cochrane Library and LILACS) to March 2016 for diagnostic accuracy studies of ICS test and standard reference tests for syphilis in pregnant women. Methodological quality was assessed using QUADAS-2 (Quality Assessment of Diagnostic Accuracy Studies). A bivariate meta-analysis was undertaken to generate pooled estimates of diagnostic parameters. Results were presented using a coupled forest plot of sensitivity and specificity and a scatter plot.

RESULTS

The methodological quality of the five included studies with regards to risk of bias and applicability concern judgements was either low or unclear. One study was judged as high risk of bias for patient selection due to exclusion of pregnant women with a previous history of syphilis, and one study was judged at high risk of bias for study flow and timing as not all patients were included in the analysis. Five studies contributed to the meta-analysis, providing a pooled sensitivity and specificity for ICS of 0.85 (95% CrI: 0.73 to 0.92) and 0.98 (95% CrI: 0.95 to 0.99), respectively.

CONCLUSIONS

This review and meta-analysis observed that rapid ICS POC tests have a high sensitivity and specificity when performed in pregnant women at antenatal clinics. However, the methodological quality of the existing evidence base should be taken into consideration when interpreting these results.

PROSPERO REGISTRATION NUMBER

CRD42016036335.

Rapid diagnostic testing to improve access to screening for syphilis in prison

OBJECTIVES

To assess the accuracy of on-site rapid treponemal test for syphilis diagnosis in women deprived of liberty in Bolivia.

MATERIAL AND METHODS

Serological tests for syphilis were performed on 219 women deprived of liberty from the San Sebastián prison in Cochabamba, Bolivia. Syphilis was diagnosed using RPR (bioMérieux) and TPPA (Fujirebio) serological tests, and the results were compared to on-site rapid treponemal test (Alere DetermineTM Syphilis TP) in whole blood. Diagnostic performance of two FTA tests were also compared (bioMérieux and Biocientífica).

RESULTS

All participants (28) with RPR+/TPPA+ had the rapid syphilis test positive (sensitivity 100%). Eleven participants had rapid syphilis test positive without RPR and TPPA both positive; nevertheless 7 of them had RPR or TPPA positive. Of 33 participants with FTA-bioMérieux positive, 22 (66.6%) had FTA-Biocientífica positive.

DISCUSSION

The rapid syphilis test Determine shows excellent performance as a screening tool among women deprived of liberty affected by high prevalence of syphilis. This test is particularly indicated when there are barriers for access to conventional serological tests. It is inexpensive, easy to use and does not require electricity and laboratory infrastructure. The FTA test performed with reagents from Biocientífica had a suboptimal sensitivity.

Point-of-Care Sexually Transmitted Infection Diagnostics: Proceedings of the STAR Sexually Transmitted Infection-Clinical Trial Group Programmatic Meeting

The STAR STI-CTG programmatic meeting reviewed point-of-care sexually transmitted infection diagnostics including current and emerging technologies, clinical and public health benefits, international applications, regulatory considerations, and future developments.

The goal of the point-of-care (POC) sexually transmitted infection (STI) Diagnostics meeting was to review the state-of-the-art research and develop recommendations for the use of POC STI diagnostics. Experts from academia, government, nonprofit, and industry discussed POC diagnostics for STIs such as Chlamydia trachomatis, human papillomavirus, Neisseria gonorrhoeae, Trichomonas vaginalis, and Treponema pallidum. Key objectives included a review of current and emerging technologies, clinical and public health benefits, POC STI diagnostics in developing countries, regulatory considerations, and future areas of development. Key points of the meeting are as follows: (i) although some rapid point-of-care tests are affordable, sensitive, specific, easy to perform, and deliverable to those who need them for select sexually transmitted infections, implementation barriers exist at the device, patient, provider, and health system levels; (ii) further investment in research and development of point-of-care tests for sexually transmitted infections is needed, and new technologies can be used to improve diagnostic testing, test uptake, and treatment; (iii) efficient deployment of self-testing in supervised (ie, pharmacies, clinics, and so on) and/or unsupervised (ie, home, offices, and so on) settings could facilitate more screening and diagnosis that will reduce the burden of sexually transmitted infections; (iv) development of novel diagnostic technologies has outpaced the generation of guidance tools and documents issued by regulatory agencies; and (v) questions regarding quality management are emerging including the mechanism by which poor-performing diagnostics are removed from the market and quality assurance of self-testing is ensured.

The cost and cost-effectiveness of rapid testing strategies for yaws diagnosis and surveillance

Background

Yaws is a non-venereal treponemal infection caused by Treponema pallidum subspecies pertenue. The disease is targeted by WHO for eradication by 2020. Rapid diagnostic tests (RDTs) are envisaged for confirmation of clinical cases during treatment campaigns and for certification of the interruption of transmission. Yaws testing requires both treponemal (trep) and non-treponemal (non-trep) assays for diagnosis of current infection. We evaluate a sequential testing strategy (using a treponemal RDT before a trep/non-trep RDT) in terms of cost and cost-effectiveness, relative to a single-assay combined testing strategy (using the trep/non-trep RDT alone), for two use cases: individual diagnosis and community surveillance.

Methods

We use cohort decision analysis to examine the diagnostic and cost outcomes. We estimate cost and cost-effectiveness of the alternative testing strategies at different levels of prevalence of past/current infection and current infection under each use case. We take the perspective of the global yaws eradication programme. We calculate the total number of correct diagnoses for each strategy over a range of plausible prevalences. We employ probabilistic sensitivity analysis (PSA) to account for uncertainty and report 95% intervals.

Results

At current prices of the treponemal and trep/non-trep RDTs, the sequential strategy is cost-saving for individual diagnosis at prevalence of past/current infection less than 85% (81–90); it is cost-saving for surveillance at less than 100%. The threshold price of the trep/non-trep RDT (below which the sequential strategy would no longer be cost-saving) is US$ 1.08 (1.02–1.14) for individual diagnosis at high prevalence of past/current infection (51%) and US$ 0.54 (0.52–0.56) for community surveillance at low prevalence (15%).

Discussion

We find that the sequential strategy is cost-saving for both diagnosis and surveillance in most relevant settings. In the absence of evidence assessing relative performance (sensitivity and specificity), cost-effectiveness is uncertain. However, the conditions under which the combined test only strategy might be more cost-effective than the sequential strategy are limited. A cheaper trep/non-trep RDT is needed, costing no more than US$ 0.50–1.00, depending on the use case. Our results will help enhance the cost-effectiveness of yaws programmes in the 13 countries known to be currently endemic. It will also inform efforts in the much larger group of 71 countries with a history of yaws, many of which will have to undertake surveillance to confirm the interruption of transmission.

Yaws is a non-venereal treponemal infection. The disease is targeted by WHO for eradication by 2020. Testing is envisaged for diagnosis to confirm of clinical cases during treatment campaigns and for surveillance to certify the interruption of transmission. However resources available to the global eradication programme are severely limited and the cost of testing must be contained. Testing requires simultaneous detection of antibodies to both treponemal and non-treponemal antigens for diagnosis of active infection. Currently, there is one commercially available rapid diagnostic test for yaws that can do just that. However, it is considerably more expensive than the available syphilis tests detecting treponemal antibodies only. We evaluate the cost and cost-effectiveness of a sequential testing strategy (using the treponemal test first, before the combined test), relative to a combined testing strategy (using only the combined test). We consider the two use cases: individual diagnosis and community surveillance. We find that the sequential strategy is cost-saving for both diagnosis and surveillance in most relevant settings. Yaws eradication programme should consider adopting the sequential strategy. Still, a cheaper trep/non-trep RDT is needed, costing no more than US$ 0.50–1.00. Our results will help enhance the cost-effectiveness of yaws programmes in the 13 countries known to be currently endemic. It will also inform efforts in the much larger group of 71 countries with a history of yaws, many of which will have to undertake surveillance to confirm the interruption of transmission.

Syphilis

Treponema pallidum subspecies pallidum (T. pallidum) causes syphilis via sexual exposure or via vertical transmission during pregnancy. T. pallidum is renowned for its invasiveness and immune-evasiveness; its clinical manifestations result from local inflammatory responses to replicating spirochaetes and often imitate those of other diseases. The spirochaete has a long latent period during which individuals have no signs or symptoms but can remain infectious. Despite the availability of simple diagnostic tests and the effectiveness of treatment with a single dose of long-acting penicillin, syphilis is re-emerging as a global public health problem, particularly among men who have sex with men (MSM) in high-income and middle-income countries. Syphilis also causes several hundred thousand stillbirths and neonatal deaths every year in developing nations. Although several low-income countries have achieved WHO targets for the elimination of congenital syphilis, an alarming increase in the prevalence of syphilis in HIV-infected MSM serves as a strong reminder of the tenacity of T. pallidum as a pathogen. Strong advocacy and community involvement are needed to ensure that syphilis is given a high priority on the global health agenda. More investment is needed in research on the interaction between HIV and syphilis in MSM as well as into improved diagnostics, a better test of cure, intensified public health measures and, ultimately, a vaccine.

Point-of-care diagnostics to improve maternal and neonatal health in low-resource settings

Each day, approximately 830 women and 7400 newborns die from complications during pregnancy and childbirth. Improving maternal and neonatal health will require bringing rapid diagnosis and treatment to the point of care in low-resource settings. However, to date there are few diagnostic tools available that can be used at the point of care to detect the leading causes of maternal and neonatal mortality in low-resource settings. Here we review both commercially available diagnostics and technologies that are currently in development to detect the leading causes of maternal and neonatal mortality, highlighting key gaps in development where innovative design could increase access to technology and enable rapid diagnosis at the bedside.

Sexually transmitted infections: challenges ahead

WHO estimated that nearly 1 million people become infected every day with any of four curable sexually transmitted infections (STIs): chlamydia, gonorrhoea, syphilis, and trichomoniasis. Despite their high global incidence, STIs remain a neglected area of research. In this Commission, we have prioritised five areas that represent particular challenges in STI treatment and control. Chlamydia remains the most commonly diagnosed bacterial STI in high-income countries despite widespread testing recommendations, sensitive and specific non-invasive testing techniques, and cheap effective therapy. We discuss the challenges for chlamydia control and evidence to support a shift from the current focus on infection-based screening to improved management of diagnosed cases and of chlamydial morbidity, such as pelvic inflammatory disease. The emergence and spread of antimicrobial resistance in Neisseria gonorrhoeae is globally recognised. We review current and potential future control and treatment strategies, with a focus on novel antimicrobials. Bacterial vaginosis is the most common vaginal disorder in women, but current treatments are associated with frequent recurrence. Recurrence after treatment might relate to evidence that suggests sexual transmission is integral to the pathogenesis of bacterial vaginosis, which has substantial implications for the development of effective management approaches. STIs disproportionately affect low-income and middle-income countries. We review strategies for case management, focusing on point-of-care tests that hold considerable potential for improving STI control. Lastly, STIs in men who have sex with men have increased since the late 1990s. We discuss the contribution of new biomedical HIV prevention strategies and risk compensation. Overall, this Commission aims to enhance the understanding of some of the key challenges facing the field of STIs, and outlines new approaches to improve the clinical management of STIs and public health.

[Incidence of congenital syphilis and factors associated with vertical transmission: data from the Birth in Brazil study]

The objectives were to estimate incidence of congenital syphilis and verify factors associated with vertical transmission. A national hospital-based study was performed in 2011-2012 with 23,894 postpartum women using an in-hospital interview and data from patient charts and prenatal cards. Univariate logistic regression was performed to verify factors associated with congenital syphilis. Estimated incidence of congenital syphilis was 3.51 per 1,000 live births (95%CI: 2.29-5.37) and vertical transmission rate was 34.3% (95%CI: 24.7-45.4). Congenital syphilis was associated with lower maternal schooling, black skin color, higher rate of risk factors for prematurity, late initiation of prenatal care, fewer prenatal visits, and lower rate of prenatal serological testing. Fetal mortality was six times higher in congenital syphilis, and newborns with congenital syphilis showed higher hospital admission rates. Congenital syphilis is a persistent public health problem in Brazil and is associated with greater social vulnerability and gaps in prenatal care.