Single-test syphilis serology: A case of not seeing the forest for the trees.

INTRODUCTION: There have been few empirical studies for diagnostic test accuracy of syphilis using a sequence of rapid tests in populations with low prevalence of syphilis such as pregnant women. This analysis describes syphilis test positivity frequency among pregnant women at an antenatal clinic in Zambia using a reverse-sequence testing algorithm for antenatal syphilis screening. METHODS: Between August 2019 and May 2023, we recruited 1510 pregnant women from a peri-urban hospital in Lusaka, Zambia. HIV positive and HIV negative women were enrolled in a 1:1 ratio. Blood collected at recruitment from the pregnant mothers was tested on-site for syphilis using a rapid treponemal test. Samples that tested positive were further tested at a different laboratory, with rapid plasma reagin using archived plasma. RESULTS: Of the total 1,421 sera samples which were screened with a rapid treponemal test, 127 (8.9%) were positive and 1,294 (91.1%) were negative. Sufficient additional samples were available to perform RPR testing on 114 of the 127 (89.8%) RDT positive specimens. Thirty-one (27.2%) of these 114 were reactive by RPR and 83 (72.8%) were negative, resulting in a syphilis overtreatment rate of 3 fold (i.e, 84/114). Insufficient sample or test kit availability prevented any testing for the remaining 89 (5.9%) participants. CONCLUSION: Use of only treponemal tests in low prevalence populations, like pregnant women, subjects individuals with non-active syphilis to the costs and possible risks of overtreatment. The use of the dual treponemal and non-treponemal tests would minimize this risk at some additional cost.

Platelet-derived major histocompatibility complex class I coating on Treponema pallidum attenuates natural killer cell lethality.

The evasive tactics of Treponema pallidum pose a major challenge in combating and eradicating syphilis. Natural killer (NK) cells mediate important effector functions in the control of pathogenic infection, preferentially eliminating targets with low or no expression of major histocompatibility complex (MHC) class I. To clarify T. pallidum's mechanisms in evading NK-mediated immunosurveillance, experiments were performed to explore the cross-talk relations among T. pallidum, NK cells, and platelets. T. pallidum adhered to, activated, and promoted particle secretion of platelets. After preincubation with T. pallidum, platelets expressed and secreted high levels of MHC class I, subsequently transferring them to the surface of T. pallidum, potentially inducing an immune phenotype characterized by the "pseudo-expression" of MHC class I on the surface of T. pallidum (hereafter referred to a "pseudo-expression" of MHC class I). The polA mRNA assay showed that platelet-preincubated T. pallidum group exhibited a significantly higher copy number of polA transcript than the T. pallidum group. The survival rate of T. pallidum mirrored that of polA mRNA, indicating that preincubation of T. pallidum with platelets attenuated NK cell lethality. Platelets pseudo-expressed the MHC class I ligand on the T. pallidum surface, facilitating binding to killer cell immunoglobulin-like receptors with two immunoglobulin domains and long cytoplasmic tail 3 (KIR2DL3) on NK cells and initiating dephosphorylation of Vav1 and phosphorylation of Crk, ultimately attenuating NK cell lethality. Our findings elucidate the mechanism by which platelets transfer MHC class I to the T. pallidum surface to evade NK cell immune clearance.

Health care of sexual partners of adolescents with gestational syphilis and their children: an integrative review. / Atenção à saúde dos parceiros sexuais de adolescentes com sífilis gestacional e seus filhos: uma revisão integrativa.

Gestational syphilis (GS) in adolescents is a challenge for Brazilian public health, with high incidence rates. Testing, diagnosis and treatment of sexual partners is essential to interrupt the chain of transmission, but since 2017 it is no longer a criterion for the proper treatment of pregnant women. We sought to analyze and synthesize the knowledge produced about the health care of sexual partners of adolescents with GS in Brazil. We carried out a systematic review in the BVS, SciELO and PubMed databases, selecting articles that addressed GS and/or congenital syphilis (CS) in adolescents aged 15 to 19 years and that included information about sexual partners. Forty-one articles were comprehensively analyzed using the WebQDA software and classified into two categories: a) Approach to sexual partners during prenatal care, and b) The role of sexual partners in the transmission cycle of GS and CS. The studies show that the partner's approach is deficient, with a lack of data on the sociodemographic profile and information on testing and treatment. In the context of Primary Health Care, there are no studies that address factors inherent to the context of vulnerability of sexual partners in relation to coping with syphilis.

A sífilis gestacional (SG) em adolescentes é um desafio para a saúde pública brasileira, com elevadas taxas de incidência. A testagem, diagnóstico e tratamento dos parceiros sexuais é indispensável para interromper a cadeia de transmissão, mas desde 2017 deixou de ser critério para o tratamento adequado da gestante. Buscamos analisar e sintetizar o conhecimento produzido sobre a atenção à saúde de parceiros sexuais de adolescentes com SG no Brasil. Realizamos uma revisão integrativa nas bases de dados BVS, SciELO e PubMed, selecionando artigos que abordavam SG e/ou sífilis congênita (SC) em adolescentes de 15 a 19 anos e que incluíam informações sobre os parceiros sexuais. Quarenta e um artigos foram analisados compreensivamente com auxílio do software WebQDA e classificados em duas categorias: (a) Abordagem dos parceiros sexuais no pré-natal, e (b) Papel dos parceiros sexuais no ciclo de transmissão da SG e da SC. Os estudos evidenciam que a abordagem do parceiro é deficitária, com ausência de dados sobre o perfil sociodemográfico e informações sobre testagem e tratamento. No âmbito da atenção primária à saúde não se encontram estudos que abordem fatores inerentes ao contexto de vulnerabilidade dos parceiros sexuais em relação ao enfrentamento da sífilis.

Estimating the Proportion of People Living With HIV Who May Benefit From the Reverse Algorithm for the Diagnosis of Incident Syphilis.

ABSTRACT: Among 8455 people engaged in HIV care in 4 US cities, 4925 (58%) had treponemal testing at care entry. Of the 4925 tested, 3795 (77%) had a nonreactive result and might benefit from the reverse algorithm for a future incident syphilis diagnosis. Furthermore, low-barrier treponemal testing as a first step in the reverse algorithm may increase syphilis screening and decrease time to treatment.

Follmann Balanitis: An Unusual Case of Syphilis.

A 33-year-old man presented with suprapubic abdominal pain and small vesicular lesions on the foreskin of the penis. Based on the presentation, he was empirically treated for genital herpes, although the herpes simplex virus swab was negative. He returned to the emergency department 4 months after his initial presentation with worsening symptoms that were consistent with balanoposthitis and cystitis. He was tachycardic and febrile on presentation. He denied any sexual contact for the last 3 months, with previous negative screening tests for sexually transmitted infections. Syphilis was eventually diagnosed during this admission. The incidence rates of syphilis have increased in recent years, and the infection is often undiagnosed given atypical manifestations. Here we present an atypical manifestation of syphilis that was initially misdiagnosed as herpes simplex virus.

Immunophenotypic variations in syphilis: insights from Mendelian randomization analysis.

Background: Infection with Treponema pallidum instigates complex immune responses. Prior research has suggested that persistent Treponema pallidum infection can manipulate host immune responses and circumvent host defenses. However, the precise role of immune cells in Treponema pallidum infection across different stages remains a contentious issue. Methods: Utilizing summary data from genome-wide association studies, we employed a two-sample Mendelian randomization method to investigate the association between 731 immunophenotypes and syphilis. Syphilis was categorized into early and late stages in this study to establish a more robust correlation and minimize bias in database sources. Results: Our findings revealed that 33, 36, and 27 immunophenotypes of peripheral blood were associated with syphilis (regardless of disease stage), early syphilis and late syphilis, respectively. Subsequent analysis demonstrated significant variations between early and late syphilis in terms of immunophenotypes. Specifically, early syphilis showcased activated, secreting, and resting regulatory T cells, whereas late syphilis was characterized by resting Treg cells. More B cells subtypes emerged in late syphilis. Monocytes in early syphilis exhibited an intermediate and non-classical phenotype, transitioning to classical in late syphilis. Early syphilis featured naive T cells, effector memory T cells, and terminally differentiated T cells, while late syphilis predominantly presented terminally differentiated T cells. Immature myeloid-derived suppressor cells were evident in early syphilis, whereas the dendritic cell immunophenotype was exclusive to late syphilis. Conclusion: Multiple immunophenotypes demonstrated associations with syphilis, showcasing substantial disparities between the early and late stages of the disease. These findings hold promise for informing immunologically oriented treatment strategies, paving the way for more effective and efficient syphilis interventions.

Gaps in the prevention of mother-to-child transmission of syphilis: a review of reported cases, South Africa, January 2020-June 2022.

INTRODUCTION: Congenital syphilis (CS) is preventable through timely antenatal care (ANC), syphilis screening and treatment among pregnant women. Robust CS surveillance can identify gaps in this prevention cascade. We reviewed CS cases reported to the South African notifiable medical conditions surveillance system (NMCSS) from January 2020 to June 2022. METHODS: CS cases are reported using a case notification form (CNF) containing limited infant demographic and clinical characteristics. During January 2020-June 2022, healthcare workers supplemented CNFs with a case investigation form (CIF) containing maternal and infant testing and treatment information. We describe CS cases with/without a matching CIF and gaps in the CS prevention cascade among those with clinical information. FINDINGS: During January 2020-June 2022, 938 CS cases were reported to the NMCSS with a median age of 1 day (interquartile range: 0-5). Nine percent were diagnosed based on clinical signs and symptoms only. During January 2020-June 2022, 667 CIFs were reported with 51% (343) successfully matched to a CNF. Only 57% of mothers of infants with a matching CIF had an ANC booking visit (entry into ANC). Overall, 87% of mothers were tested for syphilis increasing to 98% among mothers with an ANC booking visit. Median time between first syphilis test and delivery was 16 days overall increasing to 82 days among mothers with an ANC booking visit. DISCUSSION: Only 37% of CS cases had accompanying clinical information to support evaluation of the prevention cascade. Mothers with an ANC booking visit had increased syphilis screening and time before delivery to allow for adequate treatment.

Untreated maternal syphilis has devastating consequences for the foetus. Congenital syphilis (CS) is preventable through timely maternal screening and treatment with robust surveillance. We evaluated CS surveillance data to identify gaps in CS surveillance and in the prevention cascade in South Africa.

Communicable Disease Screening and Human Immunodeficiency Virus Prevention in the Emergency Department.

Emergency departments (ED) provide care to populations with high rates of communicable diseases, like HIV, hepatitis C virus, and syphilis. For many patients, the ED is their sole entry point into the healthcare system and they do not routinely access screening and prevention services elsewhere. As such, the ED can serve an important public health role through communicable disease identification, treatment, and prevention. In this article, we examine national recommendations, peer-reviewed literature, and expert consensus to provide cutting edge strategies for implementing communicable infectious disease screening and prevention programs into routine ED care.

Understanding dynamics and overlapping epidemiologies of HIV, HSV-2, chlamydia, gonorrhea, and syphilis in sexual networks of men who have sex with men.

Introduction: We aimed to investigate the overlapping epidemiologies of human immunodeficiency virus (HIV), herpes simplex virus type 2 (HSV-2), chlamydia, gonorrhea, and syphilis in sexual networks of men who have sex with men (MSM), and to explore to what extent the epidemiology of one sexually transmitted infection (STI) relates to or differs from that of another STI. Methods: An individual-based Monte Carlo simulation model was employed to simulate the concurrent transmission of STIs within diverse sexual networks of MSM. The model simulated sexual partnering, birth, death, and STI transmission within each specific sexual network. The model parameters were chosen based on the current knowledge and understanding of the natural history, transmission, and epidemiology of each considered STI. Associations were measured using the Spearman's rank correlation coefficient (SRCC) and maximal information coefficient (MIC). Results: A total of 500 sexual networks were simulated by varying the mean and variance of the number of partners for both short-term and all partnerships, degree correlation, and clustering coefficient. HSV-2 had the highest current infection prevalence across the simulations, followed by HIV, chlamydia, syphilis, and gonorrhea. Threshold and saturation effects emerged in the relationship between STIs across the simulated networks, and all STIs demonstrated moderate to strong associations. The strongest current infection prevalence association was between HIV and gonorrhea, with an SRCC of 0.84 (95% CI: 0.80-0.87) and an MIC of 0.81 (95% CI: 0.74-0.88). The weakest association was between HSV-2 and syphilis, with an SRCC of 0.54 (95% CI: 0.48-0.59) and an MIC of 0.57 (95% CI, 0.49-0.65). Gonorrhea exhibited the strongest associations with the other STIs while syphilis had the weakest associations. Across the simulated networks, proportions of the population with zero, one, two, three, four, and five concurrent STI infections were 48.6, 37.7, 11.1, 2.4, 0.3, and < 0.1%, respectively. For lifetime exposure to these infections, these proportions were 13.6, 21.0, 22.9, 24.3, 13.4, and 4.8%, respectively. Conclusion: STI epidemiologies demonstrate substantial overlap and associations, alongside nuanced differences that shape a unique pattern for each STI. Gonorrhea exhibits an "intermediate STI epidemiology," reflected by the highest average correlation coefficient with other STIs.

Syphilis seroprevalence and associated factors: A cross-sectional study in formal female sex workers in a province of Peru.

Syphilis is a sexually transmitted infection (STI) considered a public health problem that affects vulnerable and at-risk populations, such as sex workers. We designed a retrospective cross-sectional study based on the review of health evaluation records of sex workers who attended consultations to obtain comprehensive health cards at a Health Center in the Province of San Vicente de Cañete in Peru during the year 2020. We obtained sociodemographic and employment information and the RPR (rapid plasma reagin) test results to diagnose syphilis. We evaluated 220 records of sex workers with a mean age of 27.9 ±â€…6.9 years and the initiation of sexual relations of 16.0 ±â€…1.6 years, while the accumulated time they had as sex workers was 2.9 ±â€…2.4 years. 85.9% of those evaluated reported being heterosexual. The prevalence of syphilis was 7.3% (CI95: 4.2%-11.5%). Being a homosexual sex worker was significantly associated with syphilis (OR: 19.6; 95% CI: 4.8-80.0) compared to heterosexuals. The prevalence of syphilis presented a value similar to that reported in other Latin American and national studies, and it is evident that it is a health problem among sex workers.

The cost-effectiveness of syphilis screening in pregnant women: a systematic literature review.

Introduction: The cost-effectiveness study of syphilis screening in pregnant women has not been synthesized. This study aimed to synthesize the economic evidence on the cost-effectiveness of syphilis screening in pregnant women that might contribute to making recommendations on the future direction of syphilis screening approaches. Methods: We systematically searched MEDLINE, PubMed, and Web of Science databases for relevant studies published before 19 January 2023 and identified the cost-effectiveness analyses for syphilis screening in pregnant women. The methodological design quality was appraised by the Consolidated Health Economic Evaluation Reporting Standards (CHEERS) 2022 checklist. Results: In total, 17 literature met the eligibility criteria for a full review. Of the 17 studies, four evaluated interventions using different screening methods, seven assessed a combination of syphilis testing and treatment interventions, three focused on repeat screening intervention, and four evaluated the interventions that integrated syphilis and HIV testing. The most cost-effective strategy appeared to be rapid syphilis testing with high treatment rates in pregnant women who were positive. Discussion: The cost-effectiveness of syphilis screening for pregnancy has been widely demonstrated. It is very essential to improve the compliance with maternal screening and the treatment rates for positive pregnant women while implementing screening.

Digital dual test syphilis/HIV detection based on Fourier Descriptors of Cyclic Voltammetry curves.

BACKGROUND: Effective and timely detection is vital for mitigating the severe impacts of Sexually Transmitted Infections (STI), including syphilis and HIV. Cyclic Voltammetry (CV) sensors have shown promise as diagnostic tools for these STI, offering a pathway towards cost-effective solutions in primary health care settings. OBJECTIVE: This study aims to pioneer the use of Fourier Descriptors (FDs) in analyzing CV curves as 2D closed contours, targeting the simultaneous detection of syphilis and HIV. METHODS: Raw CV signals are filtered, resampled, and transformed into 2D closed contours for FD extraction. Essential shape characteristics are captured through selected coefficients. A complementary geometrical analysis further extracts features like curve areas and principal axes lengths from CV curves. A Mahalanobis Distance Classifier is employed for differentiation between patient and control groups. RESULTS: The evaluation of the proposed method revealed promising results with classification performance metrics such as Accuracy and F1-Score consistently achieving values rounded to 0.95 for syphilis and 0.90 for HIV. These results underscore the potential efficacy of the proposed approach in differentiating between patient and control samples for STI detection. CONCLUSION: By integrating principles from biosensors, signal processing, image processing, machine learning, and medical diagnostics, this study presents a comprehensive approach to enhance the detection of both syphilis and HIV. This setts the stage for advanced and accessible STI diagnostic solutions.

Prevalence of Sexually Transmitted Infections and Predictors for Loss to Follow Up among Marginalized Homeless and Migrant Communities: a Cross-Sectional Study.

Background: In Europe and Italy, marginalized communities have a higher risk for both contracting sexually transmitted infections (STI) and progressing towards adverse outcomes. Objectives: This study focuses on the screening of HIV, HBV, HCV, and syphilis among homeless individuals and agricultural migrant workers living in Apulia, Italy. It aims to assess STI prevalence and investigate factors that might hinder return to collect test results. In addition, it explores STI knowledge, attitudes, and practices among these vulnerable populations. Methods: A cross-sectional study was conducted from September 1, 2022, to September 30, 2023. Participants were recruited from community health centers and migrant camps. Blood tests for HBV, HCV, HIV, and syphilis were performed, and Knowledge, Attitude, and Practices (KAP) survey were conducted via face-to-face interviews. Descriptive and logistic regression analyses were used to assess factors influencing the return for test results. Results: A total of 149 persons were recruited, including 64 agricultural migrant workers and 85 homeless people. Overall, 24.8% (n = 37) tested positive for at least one infection, and only 50.3% (n = 75) of the screened participants returned to collect their test results. Significant disparities in STI knowledge and healthcare access were observed between the two populations, with only 14.1% (n = 9) of migrants having access to primary healthcare. At multivariable analysis, the strongest predictor for not returning for test results was being positive for HCV. Conclusions: Among homeless people and agricultural migrant workers, STI prevalence was high, and only half of the population returned to collect test results. The study underscores the urgent need for targeted interventions and policy reevaluation to address healthcare disparities in marginalized communities.

Development and validation of an individualised nomogram to predict mother-to-child transmission in pregnant women with syphilis in China: a retrospective cohort study.

OBJECTIVES: The elimination of mother-to-child transmission (MTCT) of syphilis has been set as a public health priority. However, an instrument to predict the MTCT of syphilis is not available. We aimed to develop and validate an intuitive nomogram to predict the individualised risk of MTCT in pregnant women with syphilis in China. DESIGN: Retrospective cohort study. SETTING: Data was acquired from the National Information System of Prevention of MTCT of Syphilis in Guangdong province between 2011 and 2020. PARTICIPANTS: A total of 13 860 pregnant women with syphilis and their infants were included and randomised 7:3 into the derivation cohort (n=9702) and validation cohort (n=4158). PRIMARY OUTCOME MEASURES: Congenital syphilis. RESULTS: Among 13 860 pregnant women with syphilis and their infants included, 1370 infants were diagnosed with congenital syphilis. Least absolute shrinkage and selection operator regression and multivariable logistic regression showed that age, ethnicity, registered residence, marital status, number of pregnancies, transmission route, the timing of syphilis diagnosis, stage of syphilis, time from first antenatal care to syphilis diagnosis and toluidine red unheated serum test titre were predictors of MTCT of syphilis. A nomogram was developed based on the predictors, which demonstrated good calibration and discrimination with an area under the curve of the receiver operating characteristic of 0.741 (95% CI: 0.728 to 0.755) and 0.731 (95% CI: 0.710 to 0.752) for the derivation and validation cohorts, respectively. The net benefit of the predictive models was positive, demonstrating a significant potential for clinical decision-making. We have also developed a web calculator based on this prediction model. CONCLUSIONS: Our nomogram exhibited good performance in predicting individualised risk for MTCT of syphilis, which may help guide early and personalised prevention for MTCT of syphilis.