Clinical and immunological characteristics of HIV/syphilis co-infected patients following long-term antiretroviral treatment

Objective

This study aims to analyze the efficacy of anti-syphilis treatment and the impact of syphilis events on HIV virology and immunology in HIV/syphilis co-infected patients on long-term antiretroviral therapy (ART) and to investigate the incidence and factors of syphilis recurrence/re-infection/serofast state. The insights derived from this investigation can potentially guide strategies for preventing and managing syphilis and AIDS.

Methods

A retrospective case-control study was conducted at the AIDS clinic of Peking Union Medical College Hospital from January 2003 to December 2022. The study involved 86 HIV/syphilis co-infected patients and 86 HIV mono-infected patients matched based on age, baseline CD4 + T cell counts, and viral load. We examined the clinical characteristics of HIV/syphilis co-infected patients, evaluated the efficacy of anti-syphilis treatment, and analyzed the dynamic changes in HIV virology and immunology. The Generalized Estimating Equations (GEE) model investigated the factors associated with HIV/syphilis co-infection and syphilis recurrence/reinfection/serofast state.

Results

Syphilis serofast state was observed in 11.6% (10/86) of HIV/syphilis co-infected patients after treatment, and 33.7% (29/86) had syphilis recurrence or re-infection. The overall effectiveness of syphilis treatment stood at 76.8% (63/82). Notably, the effectiveness of syphilis treatment displayed a significant correlation with baseline syphilis titers exceeding 1:128 (p = 0.003). Over the 10-year follow-up period on ART, the HLA-DR + CD8+/CD8 + % levels in the HIV/syphilis co-infected group were markedly higher than those in the HIV mono-infected group (p < 0.05). However, no significant differences were observed between the two groups regarding HIV viral load, CD4+ T cell counts, CD8+ T cell counts, CD4/CD8 ratio, and CD38 + CD8+/CD8 + % (p > 0.05). GEE analysis model revealed that elevated HLA-DR + CD8+/CD8 + % levels were associated with HIV/syphilis co-infection (OR = 1.026, 95% CI = 1.007-1.046; p = 0.007) and syphilis recurrence/reinfection/serofast state (OR = 1.036, 95% CI = 1.008-1.065; p = 0.012).

Conclusion

While HIV/syphilis co-infected patients typically receive adequate treatment, the incidence of syphilis recurrence and reinfection remain notably elevated. A heightened HLA-DR + CD8+/CD8+ % is a notable risk factor for HIV/syphilis co-infection and syphilis recurrence/reinfection/serofast state. Therefore, it is advisable to reinforce health education efforts and ensure regular follow-ups for people living with HIV undergoing ART to monitor syphilis infection or increased risk of syphilis infection.

Immunization with Tp0954, an adhesin of Treponema pallidum, provides protective efficacy in the rabbit model of experimental syphilis

Syphilis, a chronic multisystemic disease caused by spirochete Treponema pallidum subspecies pallidum infection, continues to be a serious global health problem and congenital syphilis remains a major cause of adverse outcomes in pregnancy in developing countries. The development of an effective vaccine is the most cost-effective way to eliminate syphilis, but so far has been elusive. Here, we evaluated the immunogenicity and protective efficacy of Tp0954, a T. pallidum placental adhesin, as a potential vaccine candidate in a New Zealand White rabbit model of experimental syphilis. Animals immunized with recombinant Tp0954 (rTp0954) produced high titers of Tp0954-specific serum IgG, high levels of IFN-γ from splenocytes and specific splenocyte proliferation response when compared to control animals immunized with PBS and Freund’s adjuvant (FA). Furthermore, rTp0954 immunization significantly delayed the development of cutaneous lesions, promoted inflammatory cellular infiltration at the primary lesion sites, as well as inhibited T. pallidum dissemination to distal tissues or organs when compared with that of the control animals. In addition, the naïve rabbits receiving popliteal lymph nodes from Tp0954-immunized, T. pallidum-challenged animals were not infected by T. pallidum, confirming sterile immunity. These findings suggest that Tp0954 is a potential vaccine candidate against syphilis.

Prevalence of HIV and syphilis and their co-infection among men having sex with men in Asia: A systematic review and meta-analysis

Background

Studies found that the group of men who have sex with men (MSM) is at a very high level of risk of HIV and sexually transmitted infections (STIs) in Asian regions due to multiple reasons. Although the prevalence of HIV among general people in Asia is considered low, the prevalence of HIV and Syphilis among MSM in this region was found very high and usually, it goes unnoticed. This study aimed to inspect the prevalence of and trends in HIV, Syphilis, and their co-infection among MSM in Asia.

Methods

A systematic search was performed on January 5, 2021, in PubMed, Web of Science, and Google Scholar databases. To evaluate the heterogeneity, Q-tests, and I ² were used. To explore the publication bias, Eggers' test and funnel plot were used. The random-effect model and subgroup analysis were performed due to the significant heterogeneity.

Results

A total of 2872 articles were identified, and 66 articles were included in the final analysis. The overall prevalence of HIV and Syphilis among MSM was estimated considering 69 estimates from 66 studies whereas 19 estimates of co-infection were found in 17 studies. The pooled HIV prevalence was 8.48% (CI: 7.01-9.95) and the pooled Syphilis prevalence was 9.86% (CI: 8.30-11.41) with significant heterogeneity and publication bias. The pooled prevalence of HIV and Syphilis co-infection was 2.99% (CI: 1.70-4.27) with significant heterogeneity and no publication bias. The HIV, Syphilis, and HIV-Syphilis co-infection prevalence estimates exhibited an upward trend during 2002-2017.

Conclusions

HIV, Syphilis, and their co-infection are quite prevalent among MSM in the Asia-Pacific region. Integrated and intensified intervention strategies, HIV testing, and improved access to antiretroviral treatment as well as increased awareness are needed to reduce HIV, Syphilis, and their co-infection among the discussed vulnerable group.

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

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

Two Potential Syphilis Vaccine Candidates Inhibit Dissemination of Treponema pallidum

Syphilis, caused by the spirochete Treponema pallidum subspecies pallidum, continues to be a major public health problem worldwide. Recent increases in the number of syphilis cases, in addition to the lack of an efficient vaccine against T. pallidum for humans, highlights an urgent need for the design and development of an efficacious syphilis vaccine. Here, we assess the vaccine potential of the adhesion protein Tp0136 and the outer membrane protein Tp0663. Rabbits were subcutaneously immunized with recombinant proteins Tp0136, Tp0663, or control PBS. Immunization with Tp0136 or Tp0663 generated a strong humoral immune response with high titers of IgG, as assessed by ELISA. Moreover, animals immunized with Tp0136 or Tp0663 exhibited attenuated lesion development, increased cellular infiltration at the lesion sites, and inhibition of treponemal dissemination to distant organs compared to the unimmunized animals. These findings indicate that Tp0136 and Tp0663 are promising syphilis vaccine candidates. Furthermore, these results provide novel and important information for not only understanding the pathogenic mechanisms of spirochetes, but also the development of spirochete-specific subunit vaccines.

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.

Epidemiology of lymphogranuloma venereum in New South Wales, 2006-2015

Aim

To describe the epidemiology of lymphogranuloma venereum (LGV) in New South Wales (NSW) from 2006 to 2015.

Methods

LGV notification data between 2006 and 2015 from New South Wales were analysed to describe time trends in counts and rates by gender, age group and area of residence, as well as anatomical sites of infection. A positivity ratio was calculated using the number of LGV notifications per 100 anorectal chlamydia notifications per year. Data linkage was used to ascertain the proportion of LGV cases that were co-infected with HIV.

Results

There were 208 notifications of LGV in NSW from 2006 to 2015; all were among men, with a median age of 42 years, and half were residents of inner-city Sydney. Annual notifications peaked at 57 (1.6 per 100,000 males) in 2010, declined to 16 (0.4 per 100,000 males) in 2014, and then increased to 34 (0.9 per 100,000 males) in 2015. Just under half (47.4%) of LGV cases were determined to be co-infected with HIV.

Conclusion

The number of LGV notifications each year has not returned to the low levels seen prior to the peak in 2010. Continued public health surveillance is important for the management and control of LGV.

Syphilis

Syphilis is an infectious disease caused by the spirochaete Treponema pallidum subsp. pallidum which is transmitted by sexual contact or vertical transmission during pregnancy. The incidence of syphilis has increased in the last years, mainly among men who have sex with men. Without treatment, the disease develops into different clinical stages, being able to present cardiovascular or irreversible neurological complications after a number of years. The disease is classified as early syphilis - primary, secondary and early latent syphilis (less than 12 months) - which is contagious, and as late syphilis - late latent and tertiary syphilis- which is rarely contagious. Diagnosis and management are often a challenge because of its diversity of manifestations and the difficulty of interpretation of serological tests. The treatment of syphilis is based on penicillin or doxycycline in allergic patients. Treatment failure because of resistance has been described with azithromycin. The follow up with a serological test is recommended in all patients with syphilis in order to ascertain cure after the treatment and to diagnose possible reinfections.

Syphilis reinfection is associated with an attenuated immune profile in the same individual: a prospective observational cohort study

Background

Ascertaining if the clinical and immunological response to repeat syphilis differs from that in initial syphilis may assist in designing optimal syphilis screening strategies and vaccine design.

Methods

We prospectively recruited 120 patients with a new diagnosis of (baseline) syphilis. During a 24-month follow-up period, 11 of these patients had a further diagnosis of (repeat) syphilis. We conducted a paired comparison of their plasma cyto-chemokines at baseline and repeat syphilis.

Results

Comparing to their baseline infection, paired analyses of the 11 individuals with repeat infections during follow-up revealed that these reinfections had lower concentrations of Interferon (IFN)α (0.8 [Interquartile range (IQR) 0.8–0.8 vs. 12.2 [IQR 1.6–24.2], P = 0.004) and Chemokine (C-C motif) ligand (CCL) 4 (0.9 [IQR 0.9–12.2 vs. 17.5 [IQR 4.9–32.8], P = 0.022].

Conclusion

In this small study of 11 individuals, repeat syphilis was found to present with an attenuated immune response. The relevance of these findings to the design of optimal syphilis screening programs is discussed.

Rapid progression to gummatous tertiary syphilis in a patient with HIV

Co-infection with human immunodeficiency virus-1 (HIV) and syphilis is associated with rapid progression to tertiary syphilis. This case report describes the early development of gummatous skin disease and suspected neurosyphilis in a patient with untreated HIV and approaches to treatment.

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.

A defined syphilis vaccine candidate inhibits dissemination of Treponema pallidum subspecies pallidum

Syphilis is a prominent disease in low- and middle-income countries, and a re-emerging public health threat in high-income countries. Syphilis elimination will require development of an effective vaccine that has thus far remained elusive. Here we assess the vaccine potential of Tp0751, a vascular adhesin from the causative agent of syphilis, Treponema pallidum subsp. pallidum. Tp0751-immunized animals exhibit a significantly reduced bacterial organ burden upon T. pallidum challenge compared with unimmunized animals. Introduction of lymph nodes from Tp0751-immunized, T. pallidum-challenged animals to naive animals fails to induce infection, confirming sterile protection. These findings provide evidence that Tp0751 is a promising syphilis vaccine candidate.

There are no vaccines for the prevention of syphilis, a disease caused by the bacterium Treponema pallidum subsp. pallidum. Here, the authors use an animal model of infection to show that immunization with the Tp0751 bacterial protein inhibits the pathogen's spread within the body.

Syphilis and HIV/Syphilis Co-infection Among Men Who Have Sex With Men (MSM) in Ecuador

There is a reemergence of syphilis in the Latin American and Caribbean region. There is also very little information about HIV/Syphilis co-infection and its determinants. The aim of this study is to investigate knowledge, attitudes, and practices regarding sexually transmitted infections (STIs), in particular syphilis infection and HIV/Syphilis co-infection, as well as to estimate the prevalence of syphilis among men who have sex with men (MSM) in a city with one of the highest HIV prevalence rates in Ecuador. In this study, questionnaires were administered to 291 adult MSM. Questions included knowledge about STIs and their sexual practices. Blood samples were taken from participants to estimate the prevalence of syphilis and HIV/syphilis co-infection. In this population, the prevalence of HIV/syphilis co-infection was 4.8%, while the prevalence of syphilis as mono-infection was 6.5%. Participants who had syphilis mono-infection and HIV/syphilis co-infection were older. Men who had multiple partners and those who were forced to have sex had increased odds of syphilis and HIV/syphilis co-infection. A high prevalence of syphilis and self-reported STI was observed, which warrants targeted behavioral interventions. Co-infections are a cause for concern when treating a secondary infection in a person who is immunocompromised. These data suggest that specific knowledge, attitudes, and behaviors among MSM are associated with increased odds of STIs (including HIV/syphilis co-infections) in this region of Ecuador.

Comparison of serological responses to single-dose azithromycin (2 g) versus benzathine penicillin G in the treatment of early syphilis in HIV-infected patients in an area of low prevalence of macrolide-resistant Treponema pallidum infection

OBJECTIVES

Effectiveness of single-dose azithromycin (2 g) in the treatment of early syphilis among HIV-infected patients has rarely been evaluated in the era of combination ART.

METHODS

Consecutive HIV-infected patients with early syphilis, who received 2 g single-dose azithromycin or 2.4 MU benzathine penicillin G, between 2007 and 2014, were prospectively observed. Genotypic resistance to macrolides was determined in Treponema pallidum isolates identified from clinical specimens using PCR assays. Rapid plasma reagin (RPR) titres were determined at baseline and every 3 months after treatment. Primary outcome was a decline of RPR titre by ≥4-fold at 12 months after treatment.

RESULTS

During the study period, 162 HIV-infected patients with early syphilis received benzathine penicillin G and 237 patients received azithromycin. At 12 months follow-up, the serological response rate for penicillin and azithromycin groups was 61.1% and 56.5% (P = 0.41), respectively; respective response rate was 61.1% and 65.9% (P = 0.49) if we only included patients infected with T. pallidum not harbouring macrolide resistance in the azithromycin group. In multivariate analysis, RPR titres ≥1:32 (OR 2.56; 95% CI 1.55-4.21) and prior syphilis (OR 0.54; 95% CI 0.35-0.81) were predictors of serological response. Most common adverse effects of azithromycin included diarrhoea (52.7%), nausea (22.4%), abdominal pain (18.6%), bloating (17.7%) and lassitude/somnolence (27.4%).

CONCLUSIONS

In the setting of a low prevalence of macrolide-resistant T. pallidum, 2 g single-dose azithromycin achieved a similar serological response to benzathine penicillin G in HIV-infected patients with early syphilis. Major adverse effects of azithromycin were gastrointestinal symptoms and lassitude/somnolence.

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.

Early syphilis affects markers of HIV infection

The objective of this study was to investigate if early syphilis infection affects markers of HIV infection; CD4 T cells and viral load (VL). A retrospective study was performed on 160 HIV-positive patients (111 receiving antiretroviral therapy [ART] and 49 without ART). Early syphilis diagnosis was made in HIV patients during their follow-up at the HIV/AIDS Unit at a Greek Dermatology and Venereology Unit. The patients' blood tests were available at the time of diagnosis, as well as before and 12 weeks after early syphilis diagnosis. CD4 T cell counts and VL levels were measured. It was found that syphilis infection had a negative impact on the CD4 T cell counts in both groups, with reduced CD4 T cell counts observed in 84.6% (99/111) and 79.5% (39/49) of patients receiving and not receiving ART, respectively. After treatment for syphilis, CD4 T cell counts returned to pre-treatment levels in most patients, especially those receiving ART. There was a slight and transient VL increase. Patients receiving ART had a 27% increase in VL, compared to 71.4% among patients not receiving ART. Although the VL increase was slight (41-14,000 copies/ml) in the group under treatment, 4-5% (5/111) patients did not return to pre-treatment levels. Moreover, viral mutations associated with treatment resistance were identified in these patients. Early syphilis accelerates and complicates the progression of HIV infection. Early diagnosis and treatment of syphilis may prevent infection-associated complications in most instances. Consequently, prevention of syphilis and other sexually transmitted infections is of great importance for patients infected with HIV.

Clinical and epidemiological characteristics of patients with early syphilis from three academic centres in Poland, Germany and Ireland: initial findings from the POETS study

OBJECTIVES

Syphilis recognition in HIV-positive patients has important implications. Initial data from this study, established in June 2012 to better understand the natural history of syphilis and treatment response, examine the characteristics of patients including sexual behaviour, rates of concurrent sexually transmitted infections (STI) and type of treatment given.

METHODS

Patients were recruited from Ireland, Poland and Germany. Data gathered included demographics, method of syphilis acquisition, stage of syphilis infection, HIV status, nadir and current CD4 counts and HIV viral suppression rates. Data were then subanalysed into HIV-positive and HIV-negative groups.

RESULTS

Of 175 patients recruited, 68% were HIV-positive and 86.3% were men who have sex with men. Most HIV-positive patients presented with secondary syphilis (55.7% vs 13.2%) (p=0.0001) while the majority of HIV-negative patients had primary syphilis noted at the time of recruitment (47.2% vs18.9%, p=0.0002). Approximately half of all patients had a HIV RNA viral load <40 copies/mL (55%). Previous syphilis infection occurred more frequently in HIV-positive than HIV-negative patients (p=0.0001). Concurrent STIs at the time of syphilis diagnosis were found in 26.8%, of whom 31 (25.4%) were HIV-positive (p=0.64). HIV-positive patients received doxycycline more frequently than their HIV-negative counterparts (33.6% vs 1.9%, p=0.0001) while HIV-negative patients were treated with long-acting penicillin in 88.7% of cases vs 58% of HIV-positive patients (p=0.0002).

CONCLUSIONS

A 40% rate of unsuppressed viraemia, high levels of STIs and varying treatment regimens represent a public health risk for Europe, suggesting the model of sexual healthcare delivery in HIV-positive patients requires further evaluation.

Increasing trends of syphilis among men who have sex with men in high income countries

Background The epidemiology of syphilis, and therefore the population most impacted, differs between countries. Many developed countries have reported an increase in syphilis notifications among men who have sex with men (MSM) over the past decade.

METHODS

The rates of syphilis notifications between 2000 and 2013 in the 31 countries categorised by the Organisation for Economic Co-operation and Development (OECD) as high income were investigated. Data was taken primarily from published national surveillance reports, and a male-to-female ratio substantially greater than two in syphilis notifications was taken as a proxy for the infection being disproportionately diagnosed in MSM.

RESULTS

Data was available for 27 high-income countries. The male-to-female ratio exceeded two in all but four countries. This ratio significantly increased across all geographical areas over time. Globally, the male-to-female ratio in these countries increased from 4.1 in 2000 to 7.9 in 2013 (P=0.001). Furthermore, the proportion of male cases reported as being among MSM increased over time from 26.8% to 55.0% between 2000 and 2013 (P<0.001).

CONCLUSION

These data show that in countries with high income, there is a near universal finding of increasing rates of syphilis in MSM. It is therefore clear that no country has identified an effective method to control syphilis in this population.

Treatment and outcomes of polymerase chain reaction-confirmed early syphilis

Background Syphilis is resurgent among gay and bisexual men (GBM) despite effective treatment and widely available diagnostic serology. The polymerase chain reaction assay for Treponema pallidum (TP-PCR) is available, but little is known about the clinical features and outcomes for patients testing positive by TP-PCR.

METHODS

Clinical data were collected from four medical practices for patients recording a positive TP-PCR result between 2004 and 2011. Demographic, serological, treatment and reinfection details were obtained. Results were stratified by HIV status and whether treatment conformed to international guidelines.

RESULTS

220 patients were positive for TP-PCR, of whom 92% were GBM. Seventeen (8.1%) were positive by TP-PCR before seroconversion. Almost one-third (32.1%) received treatment beyond that recommended in guidelines, and this was associated with HIV status (40.3% HIV positive vs 22.4% HIV negative, P<0.01). All but one patient with adequate follow up achieved serological cure. There was no significant difference in time to serological cure between the groups receiving standard therapy or enhanced therapy (95 vs 108 days; P=0.67) or between HIV positive and negative patients (93 vs 104 days, P=0.06). Nineteen patients were reinfected during follow up.

CONCLUSION

TP-PCR aids early diagnosis of syphilis and may be reactive before conventional serological tests. Treatment outcomes for TP-PCR-positive early infection were excellent, but a significant proportion of patients received non-standard therapy. Expanded use of syphilis PCR testing in at-risk populations is recommended since early identification and treatment is likely to be important in controlling the current epidemic in GBM.

Demographic, risk factors and motivations among blood donors with reactive serologic tests for syphilis in São Paulo, Brazil

OBJECTIVE

To identify the demographic characteristics, risk factors and motivations for donating among blood donors with reactive serologic tests for syphilis.

BACKGROUND

Post-donation interviews with syphilis seropositive blood donors improve recruitment and screening strategies.

METHODS

This case-control study compares 75 Venereal Disease Research Laboratory (VDRL) > 8, EIA+ (enzyme immunoassay) and FTA-ABS+ (fluorescent treponemal antibody); 80 VDRL-, EIA+ and FTA-ABS+; and 34 VDRL- and EIA- donors between 2004 and 2009. Donors were assessed by their demographic characteristics, sexual behaviour, history of alcohol and illicit drugs use, and motivations to donate.

RESULTS

Donors with VDRL > 8 were more likely to be divorced [AOR = 12·53; 95% confidence interval (CI) 1·30-120·81], to have had more than six sexual partners (AOR=7·1; 95% CI 1·12-44·62) and to report male-male-sex in the past 12 months (AOR=8·18; 95% CI 1·78-37·60). Donors with VDRL-, EIA+ and FTA-ABS+ were less likely to be female (AOR=0·26; 95% CI 0·07-0·96), more likely to be older (AOR=10·2; 95% CI 2·45-42·58 ≥ 39 and <60 years old) and to have had more than six sexual partners in the past 12 months (AOR = 8·37; 95% CI 1·49-46·91). There was no significant difference among groups regarding illicit drugs use; 30·7% (VDRL > 8) and 12·5% (VDRL-, EIA+ and FTA-ABS+) of donors reported that they had been at risk for HIV infection (P = 0·004). One-third of donors came to the blood bank to help a friend or a relative who needed blood.

CONCLUSION

Although donors exposed to syphilis reported and recognised some high risk behaviour, most were motivated by direct appeal to donate blood. Monitoring the risk profile of blood donors can benefit public health and improve blood safety.