Factors associated with reinfection of syphilis in reference centers for sexually transmitted infections

Syphilitic scleritis and episcleritis: A review

Scleritis and episcleritis are rare, but potentially sight-threatening forms of syphilis. To provide a full description of this neglected subset of ocular syphilis, we evaluated the English literature for reports of syphilitic scleritis and episcleritis, recording the demographics, clinical characteristics, serological data, management practices, treatment responses, and visual outcomes. Previously published descriptions of 44 patients with syphilitic scleritis (50 eyes) and 9 patients with syphilitic episcleritis (14 eyes) were identified. The predominant type of scleritis was anterior scleritis, accounting for 92.9% of cases, with nodular anterior scleritis being the most frequent subtype at 58.1%. Almost one-quarter of patients were co-infected with human immunodeficiency virus (HIV). Initial misdiagnosis was common and led to delays in initiating treatment with appropriate antibiotics. Visual outcomes were often good in both scleritis and episcleritis, irrespective of HIV infection status, although complications including scleral thinning, keratitis, and uveitis, along with permanent visual loss and an association with neurosyphilis, were reported. Response to antibiotic treatment was typically rapid, often within 1 week. With the rising global incidence of syphilis, testing patients with scleritis or episcleritis for this infectious disease is important to ensure prompt diagnosis and treatment for best ocular and systemic outcomes.

Timely Diagnosis of Incubating Syphilis Infections Using Treponema pallidum Transcription-Mediated Amplification Assay

BACKGROUND

Syphilis is a complex, multistage, sexually transmitted infection (STI) caused by the bacterium Treponema pallidum subspecies pallidum (TP). New diagnostic tools are needed to minimize transmission. In this study, we aimed to assess the additional value of an investigational transcription-mediated amplification test for TP (TP-TMA) for routine diagnostics.

METHODS

Between September 2021 and August 2022, visits by all participants of the national preexposure prophylaxis (PrEP) program at the sexual health center (SHC) in Amsterdam were included. Anal, pharyngeal, vaginal, and urine samples collected for Chlamydia trachomatis and Neisseria gonorrhoeae screening were additionally tested with the TP-TMA assay based on detection of 23S rRNA of TP.

RESULTS

In total, 9974 SHC visits by 3283 participants were included. There were 191 infectious syphilis cases diagnosed: 26 (14%) primary syphilis, 54 (29%) secondary syphilis, and 111 (58%) early latent syphilis. In 79 of the 191 (41%) syphilis cases, at least 1 sample was TP-TMA-positive. For 16 participants, the positive TP-TMA result was not concordant with routine diagnostics. Of those, 2 participants were treated for syphilis within a week before the visit. Eight participants were treated for a syphilis notification at the visit or for another STI. Five participants were diagnosed with syphilis at the following visit, and 1 participant was lost to follow-up.

CONCLUSIONS

By adding the TP-TMA assay to routine diagnostics, we identified 14 of 191 (7%) additional syphilis infections among participants of the national PrEP program. The TP-TMA assay is a useful diagnostic tool to increase syphilis case finding and thus limit the transmission of syphilis.

Reduced Risk of Syphilis Reinfection in Men Interviewed by Disease Intervention Specialists: A Pilot Study

Introduction

Syphilis is a highly transmissible sexually transmitted infection. Rising rates of infection and reinfection are of great concern to public health officials. In local health departments across the U.S., disease intervention specialists attempt to interview all people diagnosed with early syphilis, to elicit sexual partner information, and to trace and treat the partners. This method of interviewing and contact tracing is an evidence-based practice that reduces the spread of the disease in the community, but few studies address the relationship between the disease intervention specialists' interviews and index patient reinfections. We hypothesized that patients who were interviewed, patients who provided partner information, and patients with more treated partners would have a reduced risk of reinfection.

Methods

Our sample consisted of 82 men listed in the Suffolk County Department of Health Services syphilis log who were diagnosed with primary, secondary, or early latent syphilis. We determined whether and when the patients were reinfected during a set time period, from 2016 to 2020. Kaplan-Meier analyses with log-rank statistics and Cox hazard proportional models were used to calculate time to reinfection and hazard ratios.

Results

Although none of the models produced p<0.05, notable trends were observed. In subset analyses of interviewed patients, 23.8% of patients who named partners were reinfected during the study period, whereas 50% of those who did not name partners were reinfected during that time. In addition, the hazard ratio for index patients who named partners was 0.51 (95% CI=0.225, 1.170, p=0.113). When some or all the patients' partners were treated, 20% were reinfected by the end of the study, whereas 33.3% of cases with no partners treated were reinfected by the end of the study. The hazard ratio for patients with some or all partners treated was 0.48 (95% CI=0.136, 1.711, p=0.258).

Conclusions

Although none of the results was statistically significant, trends suggest that partner elicitation and partner treatment status could be associated with reduced risk of syphilis reinfection. Because this pilot study utilized a small convenience sample that was not tested for statistical power, we could not adequately address these trends. Future studies, with larger sample sizes, should address these relationships.

Syphilis vaccine: challenges, controversies and opportunities

Syphilis is a sexually or vertically (mother to fetus) transmitted disease caused by the infection of Treponema pallidum subspecie pallidum (TPA). The incidence of syphilis has increased over the past years despite the fact that this bacterium is an obligate human pathogen, the infection route is well known, and the disease can be successfully treated with penicillin. As complementary measures to preventive campaigns and early treatment of infected individuals, development of a syphilis vaccine may be crucial for controlling disease spread and/or severity, particularly in countries where the effectiveness of the aforementioned measures is limited. In the last century, several vaccine prototypes have been tested in preclinical studies, mainly in rabbits. While none of them provided protection against infection, some prototypes prevented bacteria from disseminating to distal organs, attenuated lesion development, and accelerated their healing. In spite of these promising results, there is still some controversy regarding the identification of vaccine candidates and the characteristics of a syphilis-protective immune response. In this review, we describe what is known about TPA immune response, and the main mechanisms used by this pathogen to evade it. Moreover, we emphasize the importance of integrating this knowledge, in conjunction with the characterization of outer membrane proteins (OMPs), to expedite the development of a syphilis vaccine that can protect against TPA infection.

An Updated Review of Recent Advances in Neurosyphilis

Neurosyphilis is caused by Treponema pallidum invading the central nervous system, of which the incidence is increasing worldwide. Due to its variable clinical manifestations, diagnosis of neurosyphilis remains challenging, especially the asymptomatic form. This review focuses on recent advances in neurosyphilis, including epidemiology, clinical manifestations, laboratory findings, comorbidities, diagnosis, treatment, prognosis, and basic research. The expansion of men who have sex with men and the infection of human immunodeficiency virus mainly accounted for the increasing incidence of neurosyphilis. The rate of some historically described forms of neurosyphilis in the pre-antibiotic era declined significantly; atypical features are more prevalent. Neurosyphilis, regarded as a great mimicker for neuro-ophthalmic, audio-vestibular, and psychiatric disorders, often presents concomitantly with other diseases, including metabolic disorders. Studies on long non-coding RNAs, miRNAs, chemokines, and metabolites in peripheral blood and cerebrospinal fluid may facilitate exploring the pathogenesis and identifying novel biomarkers of neurosyphilis. The drug resistance of Treponema pallidum to penicillin has not been reported; ceftriaxone was proposed to be more effective than penicillin, whereas few randomized controlled trials supported this view. This study may pave the way for further research, especially the diagnosis and treatment of neurosyphilis.

Burden of syphilis in Brazil and federated units, 1990-2016: estimates from the Global Burden of Disease Study 2019

Background:

Syphilis is a chronic infectious disease that has created challenging situations for humanity for centuries. Transmission can occur sexually or vertically, with great repercussions on populations, particularly among women and children. The present study presents information on the main burden imposed by syphilis generated by the Global Burden of Disease (GBD) Study 2019 for Brazil and its 27 federated units.

Methods:

We described the metrics of incidence, deaths, years of life lost (YLLs), years lived with disability (YLDs), and disability-adjusted life years (DALYs), standardized by age and per 100,000 inhabitants, from 1990 to 2019, and we compared the disease burden between the years 1990 and 2019.

Results:

In Brazil, the disease burden increased between 2005 and 2019 for all metrics. Although a higher incidence of syphilis was found among women in 2019, DALYs [YLLs (males: 15.9%; females: 21.8%), YLDs (males: 25.0%; females: 50.0%), and DALYs (males: 16.2%; females: 22.4%)] were higher among men. In 2019, the highest DALY rate per 100,000 inhabitants was observed in individuals aged above 50 years. The State of Maranhão presented the highest values of DALYs {1990: 165.2 [95% uncertainty interval (UI) 96.2-264.4]; 2005: 43.8 [95% UI 30.3-62.4]; 2019: 29.1 [95% UI 19.8-41.1]} per 100,000 inhabitants in the three years analyzed.

Conclusions:

The burden of syphilis has increased in recent years. Men presented higher DALYs, although the incidence of the disease was higher in women. Syphilis affects a large number of people across all age groups, causing different degrees of disability and premature death (DALYs).

A 2021 Update on Syphilis: Taking Stock from Pathogenesis to Vaccines

In 2021 the scientific community’s efforts have been focused on solving the back-breaking challenge of the COVID-19 pandemic, but sexually transmitted infections (STI) are still one of the most common global health problems. Syphilis is a systemic disease caused by the spirochaete Treponema pallidum (TP) and is one of the oldest known diseases. Its incidence has increased in the last few years and syphilis still remains a contemporary plague that continues to afflict millions of people worldwide. Despite research improvements, syphilis pathogenesis is not completely clear; clinical presentation is very heterogeneous and the diagnosis can sometimes be difficult. Furthermore, few therapeutic options are available, and a vaccine has not been found yet. In this review, we describe the most recent evidence concerning the clinical manifestation, diagnosis, treatment and vaccine prospectives for this disease.

Characterization of sexually transmitted infections, their pharmacological treatment, and recurrence in a Colombian population

Introduction:

Sexually transmitted infections are a public health problem worldwide. Their inadequate antimicrobial management has been associated with a higher risk of recurrence.

Objective:

To characterize the main sexually transmitted infections, the adherence to clinical practice guidelines, and the factors associated with recurrence in Colombia.

Materials and methods:

We conducted an observational study to identify the main sexually transmitted infections, the sociodemographic variables, and the pharmacological management in a patient cohort from a population database of 6.5 million people affiliated with the Colombian health system. We made a multivariate analysis to identify the variables associated with recurrence.

Results:

We detected 3,158 patients with a mean age of 41.8 ± 14.5 years, of whom 63.1% were men. We found 4.030 episodes of sexually transmitted infections, predominantly urethral syndrome (27.5%). Only 13.6% of patients with urethral syndrome, ulcerative syndrome, or genital warts were managed in compliance with clinical practice guidelines and 20.6% were dispensed condoms; 16.7% of patients had recurrences and being male (OR=1.32; 95%CI 1.08-1.63), <30 years old (OR=1.72; 95%CI 1.40-2.13), being treated in municipalities other than capital cities (OR=1.43; 95%CI 1.06-1.94), and having received inadequate treatment for the first episode (OR=1.93; 95%CI 1.52-2.39) were associated with recurrence.

Conclusions:

The majority of patients with sexually transmitted infections were not treated in compliance with clinical practice guidelines and those who did not have adequate management had a higher risk of recurrence.

Clinical presentation and serological diagnosis of syphilis reinfection in men living with HIV: a retrospective cohort study

OBJECTIVES

Studies on the characteristics of syphilis reinfection are scarce despite increasing numbers and proportions of cases. We aimed to gain insights into the clinical and serological presentation of reinfected men living with HIV and to evaluate diagnostic criteria for syphilis reinfection.

METHODS

We conducted a retrospective cohort study of 259 HIV-positive men diagnosed with syphilis between January 1999 and September 2015 at the University Hospital Zurich. We compared patients with a single syphilis infection (n=109) to patients with reinfections (n=150).

RESULTS

The two groups matched in age, sexual orientation and numbers of other STIs. Reinfected patients more often presented with latent syphilis than patients with a single syphilis episode (41.9% vs 8.9%; p<0.001). Although generally high venereal diseases research laboratory (VDRL) or rapid plasma reagin (RPR) titres (median 1:32) were seen in reinfected patients, 19.4% had titres ≤1:8. Treponema pallidum passive particle agglutination (TPPA) titres were significantly higher (1:81 840 vs 1:10 240; p<0.001), while IgM values were significantly lower (1.27 vs 3.5; p<0.001) in syphilis reinfections than in first infections. The TPPA increased ≥fourfold in >92.3% of reinfected patients.

CONCLUSIONS

Our data highlight the paramount importance of regularly screening patients at risk as syphilis reinfections in men living with HIV are more likely to be latent infections, that is, without symptoms. As non-treponemal tests might be biologically false-positive (up to a titre of 1:8) due to various conditions, a ≥fourfold increase of the TPPA might be considered as optional criterion for the diagnosis of syphilis reinfections. This could be especially valuable for diagnosing reinfected latent stage patients.

Recurrent ocular syphilis in a patient living with HIV

A 26-year-old male living with human immunodeficiency virus (HIV) and who had previously been treated for ocular syphilis presented to the Emergency Department with progressive vision loss and uveitis. The efficacy of standard management for neurosyphilis in HIV and recurrence was examined.

Increased repeat syphilis among HIV-infected patients: A nationwide population-based cohort study in Taiwan

Among human immunodeficiency virus (HIV)-infected individuals, syphilis is an important sexually transmitted infection (STI), and repeat infections are common. Identifying risk factors for delineating the trends in repeat syphilis are essential for STI and HIV prevention.This study is to investigate the dynamic of the syphilis epidemic among HIV-infected patients and to identify the risk factors associated with repeat syphilis.A population-based cohort design was used to analyze claim data between January 2000 and December 2010 using the Taiwan National Health Insurance Research Database. The Poisson regression test was used to identify risk factors for repeat syphilis.Of 13,239 HIV-infected patients, annual syphilis screen tests have been performed in 4,907 (37.1%) of these patients. Syphilis has been diagnosed in 956 (19.5%) patients, and 524 (10.7%) had repeat syphilis. The annual trend in repeat syphilis showed a significant increase in the study period (β = 0.23, P < .001). Younger age (adjusted incidence rate ratio [aIRR] 1.43; 95% CI 1.11-1.86), male gender (aIRR 11.14, 95% CI 4.16-29.79), a history of STIs (aIRR 1.39, 95% CI 1.21-1.59) were independently associated with repeat syphilis. The retention in HIV care and adherence to antiretroviral therapy ≥85% ([aIRR] 0.77, 95% CI 0.61-0.98; P < .001) were associated with a reduced risk of repeat syphilis.The incidence of repeat syphilis increased during 11 years of follow-up. The screening of syphilis for early diagnosis and retention in HIV care with medication adherence should be encouraged to minimize the risk of repeat syphilis in the targeted population.

Comparative genomics and full-length Tprk profiling of Treponema pallidum subsp. pallidum reinfection

Developing a vaccine against Treponema pallidum subspecies pallidum, the causative agent of syphilis, remains a public health priority. Syphilis vaccine design efforts have been complicated by lack of an in vitro T. pallidum culture system, prolific antigenic variation in outer membrane protein TprK, and lack of functional annotation for nearly half of the genes. Understanding the genetic basis of T. pallidum reinfection can provide insights into variation among strains that escape cross-protective immunity. Here, we present comparative genomic sequencing and deep, full-length tprK profiling of two T. pallidum isolates from blood from the same patient that were collected six years apart. Notably, this patient was diagnosed with syphilis four times, with two of these episodes meeting the definition of neurosyphilis, during this interval. Outside of the highly variable tprK gene, we identified 14 coding changes in 13 genes. Nine of these genes putatively localized to the periplasmic or outer membrane spaces, consistent with a potential role in serological immunoevasion. Using a newly developed full-length tprK deep sequencing protocol, we profiled the diversity of this gene that far outpaces the rest of the genome. Intriguingly, we found that the reinfecting isolate demonstrated less diversity across each tprK variable region compared to the isolate from the first infection. Notably, the two isolates did not share any full-length TprK sequences. Our results are consistent with an immunodominant-evasion model in which the diversity of TprK explains the ability of T. pallidum to successfully reinfect individuals, even when they have been infected with the organism multiple times.

Sexual Risk Behaviors of Patients with HIV/AIDS over the Course of Antiretroviral Treatment in Northern Vietnam

Antiretroviral therapy (ART) improves the health and well-being of people living with the human immunodeficiency virus (HIV, PLWH), and reduces their risk of transmitting the virus to sexual partners. However, patterns of sexual risk behavior among HIV-positive patients taking ART in Vietnam remain largely unknown. In this study, we sought to examine sexual risk behaviors and their associated factors among HIV-positive patients receiving ART in northern Vietnam. The socio-demographic characteristics, ART use, health status, and sexual behaviors of 1133 patients taking ART in the Hanoi and Nam Dinh provinces were explored through face-to-face interviews. There were 63.5% of patients who had one sex partner, while 3.6% and 5.6% of patients had sexual intercourse with casual partners or sex workers, respectively, in the previous 12 months. Most participants tended to use condoms more often with commercial sex partners (90.2%) and intimate partners (79.7%), and less often with casual partners (60.9%). Higher age (odds ratio, OR = 1.0; 95% CIs = 1.0, 1.1) or suffering pain/discomfort (OR = 1.7; 95% CIs = 1.2, 2.4) were factors more likely to be associated with multiple sex partners. Patients who were self-employed were more likely to have sexual intercourse with casual partners/sex workers (OR = 2.1; 95% CIs = 1.1, 4.0). Meanwhile, a higher score on the EuroQol visual analog scale (EQ-VAS), an unknown HIV stage, and a longer duration of ART were adversely associated with not using condoms with casual partners/sex workers. Patients with longer durations of ART had a lower likelihood of not using a condom with casual partners/sex workers (OR = 0.5; 95% CIs = 0.3, 0.8). Our study underscored a relatively high rate of unsafe sexual behaviors among HIV-positive patients. Continuing to improve the physical and psychological well-being of HIV-positive patients in Vietnam is important in reducing the spread of HIV via risky sexual behaviors. In addition, safe-sex education should be provided to older people, and to those who are self-employed.