Predictors of serological failure after treatment in HIV-infected patients with early syphilis in the emerging era of universal antiretroviral therapy use

Syphilis Serologies: A Practical Approach for the Primary Care Clinician

Syphilis serology interpretation can be challenging even for experienced providers. This article reviews the staging of syphilis and the principles of syphilis serology testing, the algorithms used in diagnosis, and guidance for their use in monitoring the response to treatment. The authors illustrate these principles through a series of clinical scenarios and describe the rationale behind the management approaches.

Meningovascular Neurosyphilis with Cerebral Hemorrhaging in a Human Immunodeficiency Virus-1-positive Patient

Meningovascular neurosyphilis is a rare manifestation of early neurosyphilis that causes infectious arteritis and ischemic infarction. We herein report a 44-year-old man with meningovascular neurosyphilis who presented with cerebral hemorrhaging. He complained of nausea, vomiting and lightheadedness. The patient tested positive for human immunodeficiency virus (HIV), and head computed tomography showed cerebral hemorrhaging in the upper right frontal lobe and left subcortical parietal lobe. Positive cerebrospinal fluid syphilis tests confirmed the diagnosis. He recovered after treatment for neurosyphilis and anti-HIV therapy. Our case highlights the importance of considering meningovascular neurosyphilis in young patients with multiple instances of cerebral hemorrhaging.

Changes in rapid plasma reagin titers in patients with syphilis before and after treatment: A retrospective cohort study in an HIV/AIDS referral hospital in Tokyo

INTRODUCTION

Although the rapid plasma reagin (RPR) test is used to determine treatment efficacy for syphilis, animal studies show that it decreases gradually after an initial increase even without treatment. Pre-treatment changes in RPR titer in humans and its relationship with post-treatment changes in RPR titer are not well known.

METHODS

We retrospectively analyzed the clinical records of syphilitic patients who underwent automated RPR (Mediace) testing twice before treatment (i.e., at diagnosis and treatment initiation) within 1-3 months at an HIV/AIDS referral hospital in Japan between 2006 and 2018. The RPR values were expressed as the ratio to the value at treatment initiation. The mean monthly relative change in the RPR after treatment was calculated on the log2 scale for each patient and analyzed by multivariable linear regression.

RESULTS

Sixty-eight patients were identified. The median age was 45 (interquartile range [IQR], 38-50), 98.5% (67/68) were men, and 97.1% (66/68) had HIV. The median RPR titer ratio at treatment initiation/diagnosis was 0.87 (IQR, 0.48-1.30). The RPR titer decreased more than twofold in 26.5% (18/68) and more than fourfold in 10.3% (7/68) before treatment. In the multivariable analysis, higher age (predicted monthly RPR relative change on the log2 scale 0.23/10 years [95% confidence interval [CI], 0.090-0.37]), history of syphilis (0.36 [95% CI, 0.07-0.65]), and a lower ratio of RPR at treatment initiation/diagnosis (-0.52/every 10-fold increase [95% CI, -0.81 to -0.22]) were associated with a slower RPR decrease after treatment.

CONCLUSIONS

In a mostly HIV patient population, RPR titer can show more than four-fold spontaneous increase or decrease within 1-3 months. Pre-treatment spontaneous decrease of RPR titer was associated with a slower decrease in post-treatment RPR titer.

Syphilis Infections, Reinfections and Serological Response in a Large Italian Sexually Transmitted Disease Centre: A Monocentric Retrospective Study

Background: Syphilis infection does not confer definitive and protective immunity against reinfection, and crucial aspects of repeated episodes of syphilis are far from being understood, especially among people living with HIV (PLWH). Methods: In order to explore the burden of syphilis in a large cohort of HIV-negative patients and PLWH, this retrospective study describes the demographics, clinical presentation and treatment outcome of patients with syphilis treated at our clinic from 2013 to 2021. Results: Within the study period, 1859 syphilis episodes (827, 44.5% first infections and 1032, 55.5% reinfections) were recorded. A total of 663 patients, of whom 347 (52%) had PLWH, were considered. Syphilis was mostly diagnosed in males (77%) and European (79%) patients. More than half of syphilis episodes were recorded during the late latent stage (64%) or during follow-up/screening visits for other diseases, while symptomatic stages led to a diagnosis in almost half of HIV-negative patients (p < 0.001). PLWH with syphilis infection were predominantly homo/bisexual (p < 0.001). A significantly higher rate of syphilis reinfection was observed in PLWH, who also demonstrated a higher range of subsequent episodes. The serofast state was found to be similar at the 6- and 12-month follow-up visits. The multivariate analysis carried out in the HIV-positive group showed that an RPR titre >1:16 was an independent predictor for serological non-response. Conclusions: Syphilis reinfections are predominantly diagnosed in HIV-positive MSM. The high rate of asymptomatic presentation among PLWH supports the role of periodical syphilis screening. In PLWH, the only baseline factor associated with an increased risk of non-response was an RPR titre >1:16, while assessment at 12 months after treatment increased the possibility of detecting a serological response, indicating that PLWH have a slower serological response to treatment.

Ceftriaxone compared with penicillin G for the treatment of neurosyphilis: study protocol for a multicenter randomized controlled trial

BACKGROUND

Neurosyphilis may cause irreversible neurological sequelae. First-line treatment consists of penicillin G, with ceftriaxone being an alternative treatment in patients allergic to penicillin. The lack of clinical data comparing the efficacy of these two drugs indicated the need for comparative clinical trials to improve national treatment guidelines in China.

METHODS/DESIGN

In this multicenter randomized controlled clinical trial, 290 patients newly diagnosed with neurosyphilis will be randomized 1:1 to treatment with aqueous crystalline penicillin G (ACPG) or ceftriaxone. Patients will be treated with standard regimens of ACPG or ceftriaxone according to Chinese National Guidelines and will be followed up for 12 months. All clinical parameters will be assessed at baseline and at follow-up 3, 6, 9, and 12 months later. The primary outcomes will include cerebrospinal fluid (CSF) white blood cell (WBC) count, serological efficacy, and clinical efficacy. The secondary outcomes will include CSF protein concentrations, Mini-Mental State Examination (MMSE) scores, imaging results, recurrence, and time to recovery from neurosyphilis. Adverse events will be monitored and recorded during the trial.

DISCUSSION

This trial will provide clinical data to determine whether ceftriaxone is non inferior to ACPG in treating neurosyphilis and will provide evidence for the improvement of treatment guidelines.

TRIAL REGISTRATION

Chinese Clinical Trial Registry ChiCTR2100047164. Registered on 9 June 2021 and updated on 23 November 2021.

Concurrent coronavirus disease 2019 and primary syphilis in a young man: A rare case report

INTRODUCTION

The global rise of syphilis infections and the ongoing coronavirus disease 2019 (COVID-19) pandemic are causes for concern. We herein report a rare case of concurrent primary syphilis and COVID-19.

CASE REPORT

A 29-year-old man was admitted with a diagnosis of COVID-19. Although COVID-19 pneumonia appeared during ciclesonide and favipiravir treatment, his symptoms improved without developing severe hypoxemia. A small, red ulcer on the left-side of his glans penis was noted and left inguinal lymph node swellings were detected on computed tomography (CT). He reported that his last engagement in sexual intercourse had been 3 months previously, and that his partner had subsequently been diagnosed with syphilis. Although both serum Treponema pallidum (TP) antibody and rapid plasma reagin (RPR) quantitative tests were negative on the day of admission, we clinically diagnosed a suspected case of primary syphilis and started treatment with amoxicillin (1500 mg/day). We subsequently learned that the TP antibody and RPR quantitative tests had been positive 4 days before starting syphilis treatment. Amoxicillin treatment was continued for 61 days, and the ulcer gradually improved. One year later, the RPR quantitative test was negative, and CT revealed a reduction in size of the inguinal lymph nodes and no residual signs of COVID-19 pneumonia.

CONCLUSION

The prevalence of syphilis has been increasing even during the COVID-19 pandemic, and the incidence of concurrent syphilis and COVID-19 might be higher than is recognized. Asking patients with COVID-19 about high-risk sexual behavior and genital lesions could help with early diagnosis of syphilis.

The treatment outcome and predictors of serological response in syphilis in a sexually transmitted infections center, China

Serology is the mainstay for syphilis treatment monitoring. Baseline rapid plasma reagin (RPR) titre, HIV status, and syphilis stage have been found to be associated with the time to serological response among syphilis patients. This study mainly aims to evaluate the time to serological response, and to identify factors affecting the serological outcome. Medical records of syphilis cases diagnosed in Peking Union Medical College Hospital (PUMCH) between 2008 and 2018 were retrospectively reviewed. Kaplan-Meier analysis was performed to evaluate the median time to serologic response and cumulative probability of serologic response over time according to different variables. Cox regression model was conducted to find factors associated with serological response. There were 984 patients diagnosed with primary, secondary, or latent syphilis cases and receiving injections of benzathine penicillin G (BPG) as initial treatment at the Peking Union Medical College Hospital (PUMCH) between 2008 and 2018. Finally, data on 571 patients, including 49 (8.6%) primary syphilis, 261 (45.7%) secondary syphilis, and 261 (45.7%) latent syphilis, were used for analysis. It took longer time to achieve serological response for subjects aged ≥45 years than younger individuals (89 days versus 58 days; p=0.008). Males achieved serological response more quickly than females (71 days versus 83 days; p = 0.011). There was a significant difference in the time to serological response according to different syphilis stages (p < 0.001), with 55 days (95% CI, 43-67 days) for primary, 57 days (95% CI, 51-63 days) for secondary, and 117 days for latent syphilis. In addition, patients with lower baseline RPR titre had longer period to achieve serological response (252 days [95% CI, 129-375 days] for RPR titre ≤1:8, 78 days [95% CI, 63-93 days] for RPR titres from 1:16 to 1:32, and 53 days [95% CI, 49-57 days] for RPR titres ≥1:64, respectively; p<0.001). However, no significant difference in time to serological response to treatment was found according to HIV coinfection status. The result of multivariate Cox regression analysis showed that being older than 45 years with latent syphilis, HIV coinfection, or with baseline RPR titre ≤1:8 was associated with slow response. Among patients followed for at least 1 year or seroreverted, 128 (36.9%) had seroreverted within a year, and 219 (63.1%) still had a positive RPR after 1 year. For multiple logistical regression, being female and HIV coinfection were significantly associated with the failure of seroreversion (OR, 0.42 [95% CI, 0.26-0.68]; p <0.001). This study revealed that younger age, higher initial RPR titre, early syphilis stage, and HIV-negative status were associated with faster serological cure. Female sex, individuals with HIV coinfection, and latent syphilis were significantly associated with the failure of seroreversion.

Management of Adult Syphilis: Key Questions to Inform the 2021 Centers for Disease Control and Prevention Sexually Transmitted Infections Treatment Guidelines

A panel of experts generated 5 "key questions" in the management of adult syphilis. A systematic literature review was conducted and tables of evidence were constructed to answer these questions. Available data suggest no clinical benefit to >1 dose of benzathine penicillin G for early syphilis in human immunodeficiency virus (HIV)-infected patients. While penicillin remains the drug of choice to treat syphilis, doxycycline to treat early and late latent syphilis is an acceptable alternate option if penicillin cannot be used. There are very limited data regarding the impact of additional antibiotic doses on serologic responses in serofast patients and no data on the impact of additional antibiotic courses on long-term clinical outcomes. In patients with isolated ocular or otic signs and symptoms, reactive syphilis serologic results, and confirmed ocular/otic abnormalities at examination, a diagnostic cerebrospinal fluid (CSF) examination is not necessary, because up to 40% and 90% of patients, respectively, would have no CSF abnormalities. Based on the results of 2 studies, repeated CSF examinations are not necessary for HIV-uninfected patients or HIV-infected patients on antiretroviral therapy who exhibit appropriate serologic and clinical responses after treatment for neurosyphilis. Finally, several important gaps were identified and should be a priority for future research.

The challenge of diagnosis and treatment of neurosyphilis in China: results from a nationwide survey

Background The uncertainty of how neurosyphilis is diagnosed and treated in clinical settings led us to investigate whether this serious manifestation of syphilis infection is properly managed in China.

METHODS

This national cross-sectional study of the diagnosis and treatment of neurosyphilis included 1392 clinicians at 398 hospitals located in 116 cities in China.

RESULTS

Of 398 hospitals, 244 (61.3%) failed to perform diagnostic laboratory tests and 181 (45.5%) failed to provide recommended treatment for neurosyphilis. Of 1392 clinicians, 536 (38.5%) had previously diagnosed patients with neurosyphilis, but 419 (78.2%) of the latter provided diagnoses that did not meet the criteria set by national guidelines. Of the 485 clinicians who had previously treated patients with neurosyphilis, 280 (57.7%) failed to follow national guidelines for treatment. Analysis indicated that clinicians working in North China (adjusted odds ratio (aOR), 4.24; 95% confidence interval (CI), 1.65-10.88), tertiary hospitals (aOR, 3.23; 95% CI, 1.63-6.41), and hospitals specialising in sexually transmitted infections (aOR, 2.49; 95% CI, 1.24-4.99) were more likely to follow national guidelines for neurosyphilis treatment.

CONCLUSION

Lack of knowledge in disease management poses a great obstacle to prevent the serious consequences of neurosyphilis in Chinese patients. More effective measures are urgently needed to improve this suboptimal situation.

A Longitudinal Case Study of Concurrent Infection with Syphilis and Human Immunodeficiency Virus During the Early Phase

Due to the low incidence of concurrent human immunodeficiency virus (HIV) and syphilis infection identified during the early phase, such as window period (WP), little is known about the clinical manifestations, diagnosis, and treatment efficacy at very early stages. One longitudinal study was conducted in a 42-year-old blood donor who was concurrently infected with syphilis and HIV. This blood donor was treated with a penicillin-based regimen and early antiretroviral therapy (ART). Sequential serological and nucleic acid tests were performed and the results were comparatively analyzed. A regular male donor who had two occasions of high-risk sexual behaviors 41 and 35 days before donation donated whole blood at the Shenzhen Blood Center. ART was initiated at the 28th day after donation (DAD), and syphilis treatment was received at the 49th DAD. Microbiological analysis using a fourth-generation anti-HIV enzyme-linked immunosorbent assay (ELISA) (4th GAHE) and electro-chemiluminesent immunoassay indicated a positive signal at the 6th DAD, while a third-generation anti-HIV ELISA (3rd GAHE) showed positive at the 26th DAD. All nucleic acid testing (NAT) for HIV RNA were reactive except the minipool NAT of 6 pooled samples at 117th DAD. The HIV viral load declined more than 4-log in copies per milliliter over 3 months, until reaching nondetectable levels at 246th DAD. Nevertheless, HIV-1 DNA was still detectable at 403rd DAD. Among all methods utilized, anti-treponema pallidum ELISA detected syphilis infection at the earliest time. A successful serological response to syphilis treatment was reached around the 80th DAD. Concurrent infection with syphilis and HIV during early phases did not significantly change the sensitivity of reagents in detection nor alter the therapeutic efficacy for the treatment of both pathogens, but might result in delayed HIV serological WP.

Comparisons of Serologic Responses of Early Syphilis to Treatment with a Single-Dose Benzathine Penicillin G Between HIV-Positive and HIV-Negative Patients

Introduction

Poorer serologic responses of early syphilis to treatment have been inconsistently reported in HIV-positive patients compared with HIV-negative patients, but the interpretation of previous studies is limited by discrepant study designs. The present study aimed to evaluate the effect of HIV infection on the treatment response to a single dose of benzathine penicillin G (BPG) for early syphilis.

Methods

From January 2015 to March 2020, adult patients with early syphilis who received a single dose of BPG were enrolled and rapid plasma reagin (RPR) titers were periodically determined. The primary outcome was serologic response, defined as at least a fourfold decline of RPR titer at 12 months of BPG treatment compared with that at baseline, which was examined in the intention-to-treat (ITT) and per-protocol analyses. Treatment failure included lack of at least a fourfold decline in RPR titers and at least a fourfold increase in RPR titers.

Results

We prospectively enrolled 184 HIV-positive and 68 HIV-negative participants with early syphilis, who were all men who have sex with men, with a higher proportion of previous syphilis (70.1%) and early latent syphilis (64.1%) among HIV-positive participants. In the ITT with last-observation-carried-forward analysis, HIV-positive participants had a significantly lower serologic response rate at 12 months of treatment than HIV-negative participants (73.4% vs. 91.2%). Of HIV-positive participants, 12.5% failed to achieve at least fourfold decline in RPR titers and 14.1% had at least a fourfold increase in RPR titers. The factors associated with 12-month serologic response were HIV infection (adjusted odds ratio [AOR] 0.33; 95% confidence interval [CI] 0.13–0.81) and RPR titer (per 1-log₂ increase, AOR 1.36; 95% CI 1.23–1.51).

Conclusion

HIV-positive patients with early syphilis had poorer serologic responses to BPG treatment than HIV-negative patients during a 12-month follow-up period.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40121-021-00450-6.

Time to Serological Cure and Associated Factors Among Syphilis Patients With and Without HIV in a Sexually Transmitted Infections Center, Thailand

BACKGROUND

Together with clinical correlation, nontreponemal titers are used to monitor treatment outcomes. Syphilis patients with HIV and without HIV coinfection were found to have different serological responses after treatment. This study aims to determine time to serological cure for treatment of syphilis and factors associated with it in patients with and without HIV.

METHOD

A descriptive study of syphilis patients who visited Bangrak STIs Center between January 1, 2007, and December 31, 2016. Univariate analysis was done to determine factors associated with serological outcomes. Survival curve analysis and multivariate Cox regression analysis were applied to compare time to serological cure between patients with various characteristics.

RESULTS

Of 497 syphilis patients, 62.1% had serological cure, 2.2% had nonresponse, 4.6% had treatment failure or reinfection, 9.9% had serofast status, and 21.2% were undetermined because of loss to follow-up. The time to serological cure was 110 days (95% confidence interval [CI], 59-163 days) and 102 days (95% CI, 94-110 days) among patients with HIV and without HIV, respectively (P = 0.162). Time to serological cure was significantly faster in early syphilis and baseline titer ≥1:32. After adjustment with the Cox regression model, patients with early syphilis were associated with serological cure with a hazard ratio of 1.75 (95% CI, 1.32-2.32). Time to serological cure among early syphilis patients was significantly longer in HIV-positive than HIV-negative patients (P = 0.002), whereas no difference was observed in late syphilis (P = 0.104).

CONCLUSION

Early syphilis was associated with faster time to serological cure. HIV patients with early syphilis took longer time to reach serological cure than did HIV-negative patients, whereas no such a difference was observed in late syphilis.

Ocular and neurosyphilis: epidemiology and approach to management

PURPOSE OF REVIEW

In the context of a resurgence of syphilis worldwide, it can be anticipated that a rise in cases of ocular, otic, and neurosyphilis will also be seen. This article reviews the current epidemiology, manifestations, and approach to management and treatment.

RECENT FINDINGS

Although studies continue investigating alternate approaches and new diagnostic tests for ocular and neurosyphilis, few data exist to change current diagnostic algorithms and approaches to diagnosis, management, or follow up.

SUMMARY

The diagnosis of neurologic and eye/ear involvement with syphilis may be delayed because of a lack of specificity of findings, low suspicion for syphilis, fluctuation in symptoms, and/or similarities in presentation to other diseases. A high index of suspicion for syphilis and re-education about the protean manifestations of syphilis by all clinicians is required provide timely diagnosis and management of ocular, otic, and neurosyphilis.

Prevalence of syphilis, neurosyphilis and associated factors in a cross-sectional analysis of HIV infected patients attending Bugando Medical Centre, Mwanza, Tanzania

Background

HIV-syphilis co-infection can enhance the rapid progression of early or late latent syphilis to neurosyphilis and can cause catastrophic neurological complications. In studies in Mwanza, syphilis affects ~ 8% of healthy outpatients and studies done in the 1990s have suggested that up to 23.5% of HIV-syphilis co-infected patients also have neurosyphilis.

Methodology

This was a cross sectional study in which adult HIV infected patients who were hospitalized or attending the outpatient Care and Treatment Clinic (CTC) were interviewed using a structured questionnaire and screened for syphilis using serum Treponema Pallidum Hemagglutination Assay (TPHA). Blood was also taken for CD4+ T cells and viral load. Those who were found to have syphilis underwent neurological examination for any neurologic deficit and were offered a lumbar puncture.

Results

The prevalence of syphilis in HIV infected patients was found to be 9.6%. The majority of patients were female (72.5%) and median age was 42 years [interquartile range, 32–50]. Most patients were on ART (99.4%). In the study population of 1748 participants, 9.6% were TPHA positive; the majority (89.2%) reported not knowing their syphilis status and not previously been treated. One hundred and forty-one participants with syphilis had neurological examinations performed. Four of these had abnormal findings that necessitated a lumbar puncture. Neurosyphilis was confirmed in one patient (0.7%).

Conclusion

The high prevalence of syphilis in HIV infected patients indicates that there is a need to increase efforts in targeting this population to reduce sexually transmitted infections. Screening for syphilis should be done for all HIV patients given the high prevalence of the infection and the risk that aggressive forms of neurosyphilis can occur despite recovery of CD4+ T cell counts in untreated syphilis.

Deciphering the serological response to syphilis treatment in men living with HIV

OBJECTIVE

To examine syphilis serology after treatment in people living with HIV. No unanimous guidelines exist in the era of increasing coinfection.

DESIGN

Retrospective review using a tertiary care clinic in Toronto from 2000 to 2017.

METHODS

The 2015 Centers for Diseases Control and Prevention syphilis guidelines were used to define an adequate serologic response. Cumulative distribution estimates and proportional hazards models accounting for interval censoring estimated the time to serologic response and seroreversion. Multistate models were used to investigate extended periods of serofast serology.

RESULTS

A total of 171 patients with syphilis met our inclusion criteria (16 primary, 53 secondary, 26 early latent, 46 late latent, 30 neurosyphilis). Serologic response was achieved by 12 months for 65 (94%) patients and by 12-18 months for four (6%) patients with primary/secondary syphilis. For latent and neurosyphilis, 94 (92%) achieved serologic response by 24 months and one (1%) at 24.1 months. 84 (49%) patients achieved seroreversion with a median (95% confidence interval) time of 2 (1.44, 2.68) years. Latent syphilis was associated with a lower likelihood of achieving serologic response [hazard ratio (HR) = 0.52, P = 0.05] and seroreversion (HR = 0.27, P < 0.001) compared with primary/secondary syphilis. The probability of moving from a new infection state to a serofast state within 1 year was high (0.65) but the 1-year probability of transitioning from a serofast state to seroreversion was low (0.27).

CONCLUSION

The majority of people living with HIV infected with syphilis will achieve an adequate serologic response as per the Centers for Diseases Control and Prevention guidelines. Seroreversion was observed in about half but can take years to occur.

Predictors of serofast state after treatment for early syphilis in HIV-infected patients

OBJECTIVES

Non-treponemal serological tests are used to monitor treatment response during syphilis infection. Syphilis- and HIV-coinfected patients may experience incomplete resolution in non-treponemal titres, which is referred to as the serofast state. The goal of this study was to evaluate risk factors for serofast state in HIV-infected patients.

METHODS

From November 2015 to June 2018, 1530 HIV-positive patients were tested for syphilis using a Treponema pallidum particle agglutination (TPPA) assay. Among TPPA-positive patients, medical records were reviewed for early syphilis infection. Serofast state was defined as a less than four-fold decrease in non-treponemal antibody titres during a 6-month follow-up period in the absence of symptoms of syphilis. Baseline characteristics were tested as predictive factors of serological response.

RESULTS

In all, 515 patients (33.7%) tested positive in TPPA assays, and in 163 patients at least one previous syphilis infection was documented. A total of 61 out of 163 patients (37.4%) were in a serofast state. A history of previous syphilis infection (61 vs. 43%; P = 0.04) was more common in serofast patients than in patients with serological cure after 6 months. Non-treponemal titres ≥ 1:32 before therapy (47 vs. 25%; P = 0.005) and adjunctive corticosteroids to prevent the Jarisch-Herxheimer reaction (35% vs 15%; P = 0.006) were associated with serological cure after 6 months, but corticosteroid therapy had no influence at 12 months. The intensity of syphilis treatment did not affect serological cure.

CONCLUSION

Corticosteroids for prevention of the Jarisch-Herxheimer reaction were associated with earlier serological cure. Although serological response is the accredited surrogate method to monitor syphilis treatment, the biological significance of the serofast state remains unclear.

Antibiotic therapy for adults with neurosyphilis

BACKGROUND

Neurosyphilis is an infection of the central nervous system, caused by Treponema pallidum, a spirochete capable of infecting almost any organ or tissue in the body causing neurological complications due to the infection. This disease is a tertiary manifestation of syphilis. The first-line treatment for neurosyphilis is aqueous crystalline penicillin. However, in cases such as penicillin allergy, other regimes of antibiotic therapy can be used.

OBJECTIVES

To assess the clinical effectiveness and safety of antibiotic therapy for adults with neurosyphilis.

SEARCH METHODS

We searched the Cochrane Library, CENTRAL, MEDLINE, Embase, LILACS, World Health Organization International Clinical Trials Registry Platform and Opengrey up to April 2019. We also searched proceedings of eight congresses to a maximum of 10 years, and we contacted trial authors for additional information.

SELECTION CRITERIA

We included randomised clinical trials that included men and women, regardless of age, with definitive diagnoses of neurosyphilis, including HIV-seropositive patients. We compared any antibiotic regime (concentration, dose, frequency, duration), compared to any other antibiotic regime for the treatment for neurosyphilis in adults.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected eligible trials, extracted data, and evaluated risk of bias. We resolved disagreements by involving a third review author. For dichotomous data (serological cure, clinical cure, adverse events), we presented results as summary risk ratios (RR) with 95% confidence intervals (CI). We assessed the quality of evidence using the GRADE approach.

MAIN RESULTS

We identified one trial, with 36 participants​ diagnosed ​with syphilis and HIV. The participants were mainly men, with a median age of 34 years. This trial, ​funded by a pharmaceutical company, compared ceftriaxone in 18 participants (2 g daily for 10 days), with penicillin G, also in 18 participants (4 million/Units (MU)/intravenous (IV) every 4 hours for 10 days). The trial reported incomplete and inconclusive results. Three of 18 (16%) participants receiving ceftriaxone versus 2 of 18 (11%) receiving penicillin G achieved serological cure (RR 1.50; 95% CI: 0.28 to 7.93; 1 trial, 36 participants very low-quality evidence); and 8 of 18 (44%) participants receiving ceftriaxone versus 2 of 18 (18%) participants receiving penicillin G achieved clinical cure (RR 4.00; 95% CI: 0.98 to 16.30; 1 trial, 36 participants very low-quality evidence). Although more participants who received ceftriaxone achieved serological and clinical cure compared to those who received penicillin G, the evidence from this trial was insufficient to determine whether there was a difference between treatment with ceftriaxone or penicillin G.In this trial, the authors reported what would usually be adverse events as symptoms and signs in the follow-up of participants. Furthermore, this trial did not evaluate recurrence of neurosyphilis, time to recovery nor quality of life. We judged risk of bias in this clinical trial to be unclear for random sequence generation, allocation, ​and blinding of participants, and high for incomplete outcome data, potential conflicts of interest (funding bias), and other bias, due to the lack of a sample size calculation. We rated the quality of evidence as very low.

AUTHORS' CONCLUSIONS

Due to low quality and insufficient evidence, it was not possible to determine whether there was a difference between treatment with ceftriaxone or Penicillin G. Also, the benefits to people without HIV and neurosyphilis are unknown, as is the ceftriaxone safety profile.Therefore, these results should be interpreted with caution. This conclusion does not mean that antibiotics should not be used for treating this clinical entity. This Cochrane Review has identified the need of adequately powered trials, which should be planned according to Standard Protocol Items: Recommendations for Interventional Trials (SPIRIT) recommendations, conducted and reported as recommended by the CONSORT statement. Furthermore, the outcomes should be based on patients' perspectives taking into account Patient-Centered Outcomes Research Institute (PCORI) recommendations.

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.

Incidence and Predictors of Serological Treatment Response in Early and Late Syphilis Among People Living With HIV

Background

Few studies have investigated predictors of serological response to syphilis treatment in people living with HIV (PLWH).

Methods

This was a retrospective, longitudinal study on PLWH who were diagnosed with and treated for syphilis who had an assessable serological response between January 2004 and June 2016. Serological treatment response (TR) was defined as a ≥4-fold decline in rapid plasma reagin (RPR) titers or a reversion to nonreactive (if RPR ≤1:4 at diagnosis) 12 months after treatment for early syphilis and 24 months after treatment for late syphilis. Factors associated with a TR were assessed with multivariate Cox proportional hazard models for recurrent events.

Results

A total of 829 episodes of syphilis (686 early, 143 late) in 564 patients were recorded. TR was observed in 732 (88%) syphilis episodes. The proportion of TR differed between early and late syphilis (89% vs 83%, respectively; P = .045). For early syphilis, TR was associated with a higher nadir CD4+ cell count (adjusted hazard ratio [AHR], 1.06; P = .029), an RPR titer >1:32 at diagnosis (AHR, 1.26; P = .009), secondary syphilis (AHR, 1.29; P = .008), and cases of syphilis diagnosed in more recent calendar years (AHR, 1.36; P < .0001). In late syphilis, TR was more likely to occur for first infections (AHR, 1.80; P = .027), for episodes that occurred in more recent years (AHR, 1.62; P = .007), and for RPR titers >1:32 at diagnosis (AHR, 2.04; P = .002). TR was not associated with the type of treatment regimen in early and late syphilis.

Conclusions

Higher RPR titers at diagnosis and a diagnosis of syphilis that was made in more recent years were associated with TR in early and late syphilis.

Risk Factors and Incidence of Syphilis in Human Immunodeficiency Virus (HIV)-Infected Persons: The HIV Outpatient Study, 1999-2015

Background

Since 2000, the incidence of syphilis has been increasing, especially among gay, bisexual, and other men who have sex with men (MSM) in the United States. We assessed temporal trends and associated risk factors for newly diagnosed syphilis infections among human immunodeficiency virus (HIV)-infected patients during a 16-year period.

Methods

We analyzed data from the HIV Outpatient Study (HOPS) cohort participants at 10 US HIV clinics during 1999-2015. New syphilis cases were defined based on laboratory parameters and clinical diagnoses. We performed Cox proportional hazards regression analyses of sociodemographic, clinical, and behavioral risk factors for new syphilis infections.

Results

We studied 6888 HIV-infected participants; 641 had 1 or more new syphilis diagnoses during a median follow-up of 5.2 years. Most participants were male (78%), aged 31-50 years, and 57% were MSM. The overall incidence was 1.8 (95% confidence interval [CI], 1.6-1.9) per 100 person-years (PY) and it increased from 0.4 (95% CI, .2-.8) to 2.2 (95% CI, 1.4-3.5) per 100 PY during 1999-2015. In multivariable analyses adjusting for calendar year, risk factors for syphilis included age 18-30 years (hazard ratio [HR], 1.3 [95% CI, 1.1-1.6]) vs 31-40 years, being MSM (HR, 3.1 [95% CI, 2.4-4.1]) vs heterosexual male, and being non-Hispanic black (HR, 1.6 [95% CI, 1.4-1.9]) vs non-Hispanic white.

Conclusions

The increases in the syphilis incidence rate through 2015 reflect ongoing sexual risk and highlight the need for enhanced prevention interventions among HIV-infected patients in care.

Lack of antiretroviral therapy is associated with higher risk of neurosyphilis among HIV-infected patients who remain serofast after therapy for early syphilis

Resolution of clinical symptoms and at least 4-fold decline in nontreponemal antibody titers after treatment of syphilis is regarded as "proof of cure." However, a substantial proportion of patients demonstrates <4-fold reduction of titers after recommended therapy (serofast state). It remains unclear whether the serofast state is indicative of persistence of bacteria or only a residual immune response.The aim of the present study was to determine the association between the serofast state and the risk of neurosyphilis in human immunodeficiency virus (HIV)-infected individuals and to identify potential predictors of neurosyphilis.Thirty-three patients with early syphilis and HIV co-infection were included. One year after the recommended treatment of syphilis, all patients who did not achieve proper serologic response underwent lumbar puncture and cerebrospinal fluid (CSF) examination.Twelve months after completing therapy for syphilis, the proportion of patients with serofast state after syphilis therapy was 36.4% (n = 12). Among them, 5 (41.7%) had neurosyphilis. Individuals who remained serofast and had neurosyphilis (n = 5) when compared to those without neurosyphilis (n = 7) were characterized by significantly lower CD4+ cell count and higher HIV RNA levels (P < .05). Moreover, a significantly higher proportion of patients with neurosyphilis was not receiving antiretroviral therapy (ART). The nonreceipt of ART independently increased the risk of neurosyphilis in the analyzed group of serofast HIV-infected patients (odds ratio = 4.5; 95% confidence interval 1.5-13.59, P = .003).Patients co-infected with HIV require careful serologic and clinical follow-up after therapy for syphilis. In all of the patients who do not respond serologically after treatment for syphilis, especially in those who are not receiving ART, lumbar puncture and CSF examination should be considered.

Serological evolution in early syphilis

INTRODUCTION

The evolution of syphilis after treatment could be affected by different factors, for example HIV. In consequence, HIV positive patients are sometimes treated with more doses of penicillin (PBG). The aim of the study is to describe and compare the serological evolution by different factors in patients with early syphilis in Barcelona.

METHODS

The serological control was made over the following year. A time analysis was performed through the study of Kaplan- Meier curves.

RESULTS

The serological control was made in 208 patients, 42.5% of whom were HIV-positive. In a Kaplan-Meier curve the median of days needed to observe the cure was 99 [97-105] without differences depending on HIV, previous syphilis, stage or RPR titters. A better evolution was observed in patients treated with doxycycline P=.02.

CONCLUSIONS

The serological evolution is similar in HIV-negative and HIV-positive patients treated according to current recommendations, observing the cure at 3 month after treatment.

Field evaluation of a smartphone-based electronic reader of rapid dual HIV and syphilis point-of-care immunoassays

OBJECTIVE

Electronic (E) devices read and quantify lateral flow-based rapid tests, providing a novel approach to assay interpretation. We evaluated the performance of one E-reader for two dual HIV and syphilis immunoassays.

METHODS

We enrolled men who have sex with men and transgender women >18 years of age seeking medical services at an STD clinic in Lima, Peru, between October 2016 and April 2017. Venous blood was tested using two dual HIV and syphilis antibody immunoassays (SD BIOLINE HIV/Syphilis Duo, Republic of Korea, and First Response HIV 1+2/Syphilis Combo, India). Reference testing included a fourth-generation ELISA for HIV antibodies and use of the Treponema pallidum particle agglutination assay for syphilis antibodies. Trained clinic staff visually inspected the immunoassay results, after which the immunoassays were read by the HRDR-200 E-reader (Cellmic, USA), an optomechanical smartphone attachment. We calculated the concordance of the E-reader with visual inspection, as well as the sensitivity of both rapid immunoassays, in detecting HIV and T. pallidum antibodies.

RESULTS

On reference testing of 283 participant specimens, 34% had HIV antibodies and 46% had T. pallidum antibodies. Using First Response, the concordance of the E-reader with visual inspection was 97% (95% CI 94% to 99%) for T . pallidum and 97% (95% CI 95% to 99%) for HIV antibodies. Using SD BIOLINE, the concordance of the E-reader with visual inspection was 97% (95% CI 94% to 99%) for T. pallidum and 99% (95% CI 98% to 99%) for HIV antibodies. For both immunoassays, the sensitivity for HIV antibodies was 98% (95% CI 93% to 100%) and the sensitivity for T. pallidum antibodies was 81% (95% CI 73% to 87%).

CONCLUSIONS

E-reader results correlated well with visual inspection. The sensitivities of both rapid assays were comparable with past reports. Further evaluation of the E-reader is warranted to investigate its utility in data collection, monitoring and documentation of immunoassay results.

Rate of Decline in Nontreponemal Antibody Titers and Seroreversion After Treatment of Early Syphilis

BACKGROUND

Syphilis management is complex and demonstration of treatment response requires monitoring of nontreponemal antibody titers for a ≥ 4-fold decline and/or seroreversion to nonreactive titers.

METHODS

We evaluated data from a multicenter clinical trial of syphilis treatment conducted from 2000 to 2009 involving human immunodeficiency virus (HIV)-negative patients 18 years or older with early syphilis. To assess the rate of titer decline and seroreversion after effective therapy, rapid plasma reagin (RPR) titers were analyzed at 1, 3, 6, 9, and 12 months among patients with an appropriate treatment response. We plotted the rate of RPR titer decline after treatment, estimated the frequency of seroreversion, and conducted multivariate analyses to assess characteristics associated with seroreversion.

RESULTS

Among 369 (79.4%) of 465 HIV-negative patients with early syphilis who had an appropriate treatment response, 333 participants had complete RPR data over 12 months. Although the decline in RPR titers was ≥ 4-fold among 88.0% (293/333) of participants at 3 months and ≥ 8-fold among 77.8% at 6 months, only 9.6% achieved complete RPR seroreversion at 6 months and 17.1% at 12 months after therapy. Male sex (adjusted odds ratio, 4.3; 95% confidence interval, 1.8-10.5) and baseline RPR titers ≤ 1:32 (adjusted odds ratio, 14.5; 95% confidence interval, 6.8-31.2) were associated with higher odds of seroreversion compared with females and titers > 1:32, respectively.

CONCLUSIONS

Despite a ≥ 4-fold RPR titer decline after treatment, the majority of HIV-negative patients with early syphilis failed to have seroreversion at 12 months. Nontreponemal antibody titers often persist despite an appropriate treatment response.

Factors associated with syphilis treatment failure and reinfection: a longitudinal cohort study in Shenzhen, China

Background

The treatment failure and reinfection rates among syphilis patients are high, and relevant studies in China are limited. The aim of this study was to detect the rates of treatment failure and reinfection after syphilis treatment and to explore the potential associated factors.

Methods

We conducted a longitudinal cohort study in a sexually transmitted disease clinic, the Department of Dermatology and Venereology in Nanshan Center for Chronic Disease Control. Serological testing was performed at baseline and throughout the 2-year follow-up for syphilis patients. To identify potential predictors of treatment outcomes, multivariate logistics analyses were utilized to compare the demographic and clinical characteristics of patients with serological failure/reinfection to those with serological cure/serofast.

Results

From June 2011 to June 2016, a total of 1133 patients were screened for syphilis. Among the 770 patients who completed the 2-year follow-up, 510 first-diagnosed patients were included in the final analysis. Multivariate logistics analysis revealed the stage of syphilis (secondary syphilis VS. primary syphilis: adjusted odds ratio, 3.50; 95% confidence interval, 1.11-15.47; p = 0.04), HIV status (positive VS. negative: adjusted odds ratio, 3.06; 95% confidence interval, 1.15-8.04; p = 0.02) and frequency of condom use (always use VS. never use: adjusted odds ratio, 0.28; 95% confidence interval 0.08-0.75; p = 0.02) were significantly associated with the serological outcome.

Conclusions

The clinical implications of our findings suggest that it is very important to perform regular clinical and serologic evaluations after treatment. Health counseling and safety education on sex activity should be intensified among HIV-infected patients and secondary syphilis patients after treatment.

Single Dose Versus 3 Doses of Intramuscular Benzathine Penicillin for Early Syphilis in HIV: A Randomized Clinical Trial

Background

Patients coinfected with syphilis and human immunodeficiency virus (HIV) may have a slower decrease in rapid plasma reagin (RPR) titers. Currently a single dose of 2.4 million units of intramuscular benzathine penicillin G (BPG) is recommended for the treatment of early syphilis. Some observational studies have suggested that this regimen may lead to high failure rates in coinfected patients.

Methods

We conducted an open-label randomized clinical trial to compare the efficacy of single-dose and 3-dose regimens of BPG for the treatment of early syphilis in HIV-infected individuals. RPR titers were monitored every 3 months. Treatment success was defined as a decrease in RPR titers of ≥2 dilutions (4-fold) during a 12-month follow-up period.

Results

Sixty-four patients were included. In the intention-to-treat analysis, treatment success rates were 80% (28 of 35 subjects) and 93% (27 of 29 subjects) in the single-dose and 3-dose regimens, respectively (absolute difference, 13% [95% confidence interval {CI}, -5% to 30%; P = .17). In the per-protocol analysis, success rates were 93% (27 of 29) and 100% in the single-dose and 3-dose regimens, respectively (absolute difference, 7% [95% CI, -7% to 22%]; P = .49). CD4 T-cell count, RPR titer and syphilis stage did not affect treatment results.

Conclusions

When compared with a single dose of BPG, a 3-dose regimen did not improve syphilis serological outcomes. Our results support the Centers for Disease Control and Prevention recommendation of a single dose of BPG in HIV-infected patients with early syphilis.

Clinical Trials Registration

NCT02611765.

Factors associated with syphilis incidence in the HIV-infected in the era of highly active antiretrovirals

After several years of steady decline, syphilis is reemerging globally as a public health hazard, especially among people living with human immunodeficiency virus (HIV). Syphilis resurgence is observed mainly in men who have sex with men (MSM), yet other transmission groups are affected too. In this manuscript, we study the factors associated with syphilis incidence in the Swiss HIV cohort study in the era of highly effective antiretrovirals. Using parametric interval censored models with fixed and time-varying covariates, we studied the immunological, behavioral, and treatment-related elements associated with syphilis incidence in 3 transmission groups: MSM, heterosexuals, and intravenous drug users. Syphilis incidence has been increasing annually since 2005, with up to 74 incident cases per 1000 person-years in 2013, with MSM being the population with the highest burden (92% of cases). While antiretroviral treatment (ART) in general did not affect syphilis incidence, nevirapine (NVP) was associated with a lower hazard of syphilis incidence (multivariable hazard ratio 0.5, 95% confidence interval 0.2-1.0). We observed that condomless sex and younger age were associated with higher syphilis incidence. Moreover, time-updated CD4, nadir CD4, and CD8 cell counts were not associated with syphilis incidence. Finally, testing frequency higher than the recommended once a year routine testing was associated with a 2-fold higher risk of acquiring syphilis. Condomless sex is the main driver of syphilis resurgence in the Swiss HIV Cohort study; ART and immune reconstitution provide no protection against syphilis. This entails targeted interventions and frequent screening of high-risk populations. There is no known effect of NVP on syphilis; therefore, further clinical, epidemiological, and microbiological investigation is necessary to validate our observation.

Early syphilis treatment in HIV-infected patients: single dose vs. three doses of benzathine penicillin G

BACKGROUND

Current treatment guidelines for early stages of syphilis are the same regardless of HIV serostatus. There is still controversy about the best treatment for syphilis in HIV patients and the current recommendations are based on limited data.

OBJECTIVE

The primary goal of this study was to compare the serological response rates to a single dose vs. three weekly doses of benzathine penicillin G (BPG) in HIV-infected patients with early syphilis and to assess the adequacy of current recommendations.

METHODS

Clinical and laboratory data of HIV patients with early syphilis treated in Sexually Transmitted Disease Clinic between January 2000 and December 2014 were recorded. A good serological response was defined as a ≥4-fold decline in Venereal Disease Research Laboratory (VDRL) titre within 12 months after treatment. Serological failure was defined as a lack of at least fourfold decrease in VDRL titres within 12 months after treatment.

RESULTS

After applying inclusion and exclusion criteria, 60 patients were enrolled in the study. Seventeen (28.3%) patients were treated with a single dose of BPG, while in 43 (71.7%) patients, three weekly doses were used. Fifty eight (96.7%) had a good serological response at 12 months and seroconversion was confirmed in 29 (48.3%) patients. There was no statistically significant difference between the two treatment groups regarding serological response, seroconversion rate and the time needed to obtain a good serological response. Furthermore, treatment response was not affected by the number of CD₄ cells.

CONCLUSIONS

The results of our study support the current international treatment guidelines, recommending early syphilis treatment with a single dose of BPG in HIV patients.

A systematic review of syphilis serological treatment outcomes in HIV-infected and HIV-uninfected persons: rethinking the significance of serological non-responsiveness and the serofast state after therapy

BACKGROUND

Syphilis remains a global public health threat and can lead to severe complications. In addition to resolution of clinical manifestations, a reduction in nontreponemal antibody titers after treatment is regarded as "proof of cure." However, some patients manifest < 4-fold decline ("serological non-response") or persistently positive nontreponemal titers despite an appropriate decline ("serofast") that may represent treatment failure, reinfection, or a benign immune response. To delineate these treatment phenomena, we conducted a systematic review of the literature regarding serological outcomes and associated factors among HIV-infected and -uninfected subjects.

METHODS

Six databases (PubMed, Embase, CINAHL, Web of Science, Scopus, and BIOSIS) were searched with no date restrictions. Relevant articles that evaluated serological treatment responses and correlates of serological cure (≥ four-fold decline in nontreponemal titers) were included.

RESULTS

We identified 1693 reports in the literature, of which 20 studies met selection criteria. The median proportion of patients who had serological non-response was 12.1% overall (interquartile range, 4.9-25.6), but varied depending on the time points after therapy. The serofast proportion could only be estimated from 2 studies, which ranged from 35.2-44.4%. Serological cure was primarily associated with younger age, higher baseline nontreponemal titers, and earlier syphilis stage. The relationship between serological cure and HIV status was inconsistent; among HIV-infected patients, CD4 count and HIV viral load was not associated with serological cure.

CONCLUSIONS

Serological non-response and the serofast state are common syphilis treatment outcomes, highlighting the importance of determining the immunological and clinical significance of persistent nontreponemal antibody titers after therapy.

Syphilis testing, typing, and treatment follow-up: a new era for an old disease

PURPOSE OF REVIEW

The past 15 years have seen a dramatic increase in syphilis diagnoses in several regions including China, North America, Western Europe and Australia. Worldwide, the disease remains prevalent, contributing to substantial adult morbidity and neonatal mortality. Testing and treatment strategies are largely informed by data from the early antibiotic era, but increasing use of molecular diagnostics and new screening strategies could improve the management of syphilis substantially.

RECENT FINDINGS

The review explores new testing strategies for syphilis, including the importance of screening test selection and advances in point-of-care diagnostics. It then examines molecular studies of Treponema pallidum, covering typing; macrolide resistance; association between genotype and phenotype and the use of PCR in testing and monitoring strategies.

SUMMARY

Clinicians should be aware of testing strategies employed by their laboratories to ensure optimal sensitivity and specificity. Locally available T. pallidum PCR assays may improve the diagnosis of early disease and inform antibiotic choice. Robust serologic follow-up is still required, but predictors of potential treatment failure, including PCR-measured bacterial load, have been identified. Re-treatment should be considered for patients in the serofast state. The publication of T. pallidum genomes would allow further and more detailed study of strains and disease pathogenesis.

[Sexually transmitted coinfections. HIV coinfections]

Coinfections of sexually transmitted infections are frequent due to the same transmission routes which may facilitate the transmission of other sexually transmitted infections. Sexually transmitted coinfections are associated with atypical and generally more severe clinical features, more complications, resistency to treatment, unfavourable outcome, and worse prognosis. Sexually transmitted infections may increase the likelihood of acquiring and transmission of HIV infection. The authors summarize the most important characteristics of sexually transmitted infections (such as HIV and hepatitis B virus, HIV and hepatitis C virus, HIV and syphilis, HIV and gonorrhoeae, HIV and chlamydia coinfections). These infections are more frequent in HIV infected patients than in the normal population. The shared transmission routes, impairment of the immune response, elevated cytokine levels and the associated inflammatory milieu produce local tissue damage, breaches in mucosal epithelium, which increases the risk of human immunodeficiency virus infection. Regular screening for sexually transmitted infections, use of more sensitive diagnostic methods, improved reporting and avoidance of unsafe sexual behaviour among certain subpopulations as well as education are essential in the prevention of sexually transmitted coinfections.

Current standards for syphilis treatment: comparing the russian and foreign guidelines (part II)

The introduction of penicillin has been a breakthrough in the treatment of syphilis. For 70 years, penicillin remains the preferred drug for the treatment of all forms of the disease; its effectiveness has been proven by wide experience gained from clinical observations. However, a very limited number of published meta-analyzes, systematic reviews and data from randomized controlled trials on the comparative assessment of the effectiveness of various antibiotics and treatment regimens are currently available. Some aspects of syphilis treatment are insufficiently developed, particularly, the treatment schedules for neurosyphilis, syphilis in pregnancy, syphilis in HIV-infected individuals and persons allergic to penicillin. There are disagreements in the assessment of the clinical significance of serofast state after a course of antibiotic therapy. There is no uniform approach to the management of patients with treatment failures. This article compares the Russian standards for syphilis treatment set out in the «Federal guidelines for the management of patients with syphilis» with the current European recommendations of the International Union against Sexually Transmitted Infections (IUSTI) and the recommendations of the US Centers for Disease Control and Prevention (CDC). The peculiarities of these guidelines, their strengths and shortcomings, as well as controversial issues of syphilis therapy are discussed. The differences between the domestic and foreign recommendations are more significant in the section concerning the treatment of syphilis than in the section of diagnosis.

Treatment of syphilis: a systematic review

IMPORTANCE

The incidence of syphilis in the United States is increasing; it is estimated that more than 55,000 new infections will occur in 2014. Treatment regimens are controversial, especially in specific populations, and assessing treatment response based on serology remains a challenge.

OBJECTIVE

To review evidence regarding penicillin and nonpenicillin regimens, implications of the "serofast state," and treatment of specific populations including those with neurosyphilis or human immunodeficiency virus (HIV) infection and pregnant women.

EVIDENCE REVIEW

We searched MEDLINE for English-language human treatment studies dating from January 1965 until July 2014. The American Heart Association classification system was used to rate quality of evidence.

FINDINGS

We included 102 articles in our review, consisting of randomized trials, meta-analyses, and cohort studies. Case reports and small series were excluded unless they were the only studies providing evidence for a specific treatment strategy. We included 11 randomized trials. Evidence regarding penicillin and nonpenicillin regimens was reviewed from studies involving 11,102 patients. Data on the treatment of early syphilis support the use of a single intramuscular injection of 2.4 million U of benzathine penicillin G, with studies reporting 90% to 100% treatment success rates. The value of multiple-dose treatment of early syphilis is uncertain, especially in HIV-infected individuals. Less evidence is available regarding therapy for late and late latent syphilis. Following treatment, nontreponemal serologic titers should decline in a stable pattern, but a significant proportion of patients may remain seropositive (the "serofast state"). Serologic response to treatment should be evident by 6 months in early syphilis but is generally slower (12-24 months) for latent syphilis. Evidence defining treatment for HIV-infected persons and for pregnant women is limited, but available data support penicillin as first-line therapy.

CONCLUSIONS AND RELEVANCE

The mainstay of syphilis treatment is parenteral penicillin G despite the relatively modest clinical trial data that support its use.

A single dose of benzathine penicillin G is as effective as multiple doses of benzathine penicillin G for the treatment of HIV-infected persons with early syphilis

BACKGROUND

Treatment guidelines recommend the use of a single dose of benzathine penicillin G (BPG) for treating early syphilis in human immunodeficiency virus (HIV)-infected persons. However, data supporting this recommendation are limited. We examined the efficacy of single-dose BPG in the US Military HIV Natural History Study.

METHODS

Subjects were included if they met serologic criteria for syphilis (ie, a positive nontreponemal test [NTr] confirmed by treponemal testing). Response to treatment was assessed at 13 months and was defined by a ≥4-fold decline in NTr titer. Multivariate Cox proportional hazard regression models were utilized to examine factors associated with treatment response.

RESULTS

Three hundred fifty subjects (99% male) contributed 478 cases. Three hundred ninety-three cases were treated exclusively with BPG (141 with 1 dose of BPG). Treatment response was the same among those receiving 1 or >1 dose of BPG (92%). In a multivariate analysis, older age (hazard ratio [HR], 0.82 per 10-year increase; 95% confidence interval [CI], .73-.93) was associated with delayed response to treatment. Higher pretreatment titers (reference NTr titer <1:64; HR, 1.94 [95% CI, 1.58-2.39]) and CD4 counts (HR, 1.07 for every 100-cell increase [95% CI, 1.01-1.12]) were associated with a faster response to treatment. Response was not affected by the number of BPG doses received (reference, 1 dose of BPG; HR, 1.11 [95% CI, .89-1.4]).

CONCLUSIONS

In this cohort, additional BPG doses did not affect treatment response. Our data support the current recommendations for the use of a single dose of BPG to treat HIV-infected persons with early syphilis.

One dose versus three weekly doses of benzathine penicillin G for patients co-infected with HIV and early syphilis: a multicenter, prospective observational study

BACKGROUND

One dose of benzathine penicillin G (BPG) has been recommended for HIV-infected patients with early syphilis (primary, secondary, and early latent syphilis) in the sexually transmitted diseases treatment guidelines, but clinical data to support such a recommendation are limited.

METHODS

We prospectively observed the serological response to 1 or 3 weekly doses of BPG in HIV-infected adults who sought treatment of early syphilis at 8 hospitals around Taiwan. Rapid plasma reagin (RPR) titers were followed every 3-6 months after treatment. The serological response was defined as a 4-fold or greater decline in RPR titers at 12 months of treatment. The missing values were treated by following the last-observed-carried-forward principle. We hypothesized that 1 dose was non-inferior to 3 weekly doses of BPG with the non-inferiority margin for the difference of serological response set to 10%.

RESULTS

Between 2007 and 2012, 573 patients completed at least 12 months of follow-up: 295 (51.5%) receiving 1 dose of BPG (1-dose group) and 278 (48.5%) 3 doses (3-dose group). Overall, 198 patients (67.1%; 95% confidence interval [CI], 61.4-72.5%) in the 1-dose group achieved serological response at 12 months, as did 208 patients (74.8%; 95% CI, 69.3-79.8%) in the 3-dose group (one-sided 95% CI of the difference, 15.1%). In the multivariate analysis, secondary syphilis (adjusted odds ratio [AOR], 1.90; 95% CI 1.17-3.09), RPR titer ≥32 (AOR, 1.93; 95% CI, 1.38-2.69), and 3 doses of BPG (AOR, 1.68; 95% CI, 1.20-2.36) were independently associated with a serological response. The time to the first episode of treatment failure was 1184 (standard deviation [SD], 70.5) and 1436 (SD, 80.0) days for 1- and 3-dose group, respectively.

CONCLUSIONS

Single-dose BPG resulted in a higher serological failure rate and shorter time to treatment failure than 3 weekly doses of BPG in the treatment of early syphilis in HIV-infected patients.