Canadian Public Health Laboratory Network laboratory guidelines for congenital syphilis and syphilis screening in pregnant women in Canada

Interventions in maternal syphilis care globally: A scoping review

Infectious and Congenital Syphilis rates continue to rise globally. Current recommendations for syphilis screening and treatment may be insufficient, and there is a pressing need for improved programs and services to address the increase in cases. A scoping review was conducted to examine approaches to maternal syphilis screening and treatment. Theoretical underpinnings and the key characteristics of these interventions were studied to identify gaps in the existing literature to guide future research. Developing a modified version of the socio-ecological model to guide data analysis, we included 33 academic studies spanning 31 years, covering a range of interventions, programs, and policies globally. We highlight key facets of interventions aligning with the five levels of the modified model that include: individual, interpersonal, institutional, community and policy. In this review, we provide valuable insights into the characteristics and principles of maternal syphilis screening and treatment interventions.

Prevalence of syphilis coinfection in hepatitis C virus positive prenatal patients from Alberta during a pilot routine screening program

BACKGROUND: Alberta routinely screens pregnant patients for select communicable diseases. Hepatitis C virus (HCV) was added to the prenatal screening panel as part of a provincial pilot program in February 2020. This retrospective cross-sectional study aimed to characterize the prevalence of syphilis coinfections in prenatal patients infected with HCV following implementation of the pilot program.METHODS: Routine prenatal HCV and syphilis testing data were extracted from the Public Health Laboratory Information System over a 21-month period. HCV positivity was defined as HCV enzyme immunoassay (EIA) reactive with detected HCV ribonucleic acid (RNA) following molecular confirmation, and positive results were examined for syphilis coinfections. All patients reactive on a syphilis EIA and confirmatory Treponema pallidum particle agglutination (TPPA) or follow-up rapid plasma reagin (RPR) test were considered positive for syphilis. Descriptive statistics for coinfected patients were analyzed. RESULTS: Eighty-seven prenatal patients were identified to be positive for HCV. Of those, 19 (21.8%) were reactive on the syphilis EIA and 17 (19.5%) had confirmed infections with the TPPA or RPR tests. For HCV/syphilis coinfected patients, the majority resided in metropolitan regions (64.6%), were from the lowest income quintile neighbourhoods (47.1%) and had previously tested positive for HCV (82.4%) and syphilis (64.6%) at the public health laboratory. CONCLUSIONS: The prevalence of syphilis coinfections in prenatal patients infected with HCV is high in Alberta. HCV/syphilis coinfection prevalence should be further investigated in other jurisdictions and prenatal cohorts to better understand testing and treatment options for prevention of congenital transmission.

Characteristics of polymerase chain reaction-positive syphilis cases in Manitoba, Canada, 2017 to 2020: Demographic analysis, specimen types, and Treponema pallidum gene targets

BACKGROUND

A resurgence of syphilis infections has been described in a number of countries including Canada in the last decade.

METHODS

This study identified polymerase chain reaction (PCR) positive syphilis cases based on detection of Treponema pallidum genes (polA, tpp47, and bmp) in 3,350 clinical specimens obtained from patients in the province of Manitoba, Canada between 2017 and 2020. Patient demographics were obtained from specimen requisition forms.

RESULTS

PCR identified 740 syphilis cases: 718 were adolescents and adults, while 22 were congenital syphilis cases. For non-congenital syphilis investigation, the clinical specimens with the highest yield of positive PCR results were genital (632), oral (73), and anal (55), while for congenital syphilis, they were nasal or nasopharyngeal secretions (20), followed by blood (5) and umbilical cord (4). Female syphilis cases appeared younger (61.7% between 14 and 29 years), while male syphilis cases appeared older (58.4% between 30 and 65 years). Although, overall more syphilis cases (62.7%) occurred in the urban cities; the proportion of urban cases showed a significant decline from 87.0% in 2017 to 55.6% in 2020, while in rural regions it increased from 13.0% in 2017 to 44.4% in 2020. Most (98.8%) PCR- positive specimens were found to contain all three T. pallidum genes and 99.8% also displayed the macrolide resistance genotype.

CONCLUSIONS

This study identified the clinical specimen types and T. pallidum genes most suitable for PCR diagnosis of syphilis. Changing demographics of cases were noted over time.

British Columbia's Experience after Implementation of the Treponema pallidum Reverse Algorithm and PCR Detection, 2015 to 2020

British Columbia (BC) implemented the syphilis reverse screening algorithm and Treponema pallidum PCR testing in 2014. We summarize the performance characteristics of the algorithm, together with PCR direct detection, and report on syphilis cases identified from 2015 to 2020. Prior to 2015, samples for syphilis diagnosis were first screened by rapid plasma reagin (RPR). As of 2015, sera were screened by the Siemens Advia Centaur syphilis assay (enzyme immunoassay [EIA]). Positive and equivocal samples were reflex tested by a T. pallidum passive particle agglutination assay (TPPA) and RPR. We used T. pallidum DNA PCR on clinical samples and restriction fragment length polymorphism analysis to identify azithromycin resistance mutations. Case/epidemiological data were obtained from the BC surveillance system. Of 1,631,519 samples screened by the EIA, 72,492 (4.4%) were positive and 187 (<0.1%) were equivocal. Of EIA-positive/equivocal samples, 10.6% were false positive, and false positivity was higher at lower EIA indices. The reverse algorithm detected 4,693 late latent syphilis cases that likely would have been missed by RPR screening. PCR had a very high sensitivity of 100% versus 52.9% and 52.4% for dark-field (DF) and immunofluorescence (IF) microscopy, respectively. The azithromycin resistance mutation A2058G was identified in 96% of PCR-positive samples, and A2059G was identified in 4%. Annually, there were 944 to 1,467 syphilis cases, with 62% in men who reported male sexual partners. The reverse algorithm had a low false-positive rate and very few equivocal screening results but did identify previously undiagnosed late latent syphilis cases. PCR was more sensitive than both DF and IF microscopy for direct diagnosis and enabled monitoring for azithromycin resistance. IMPORTANCE In this study, we summarize the performance characteristics of the algorithm, together with PCR direct detection and epidemiological analysis, and report on syphilis cases identified from 2015 to 2020. This allowed us to paint a complete picture of the outcome of the utilization of the reverse algorithm for diagnosing syphilis cases. The study clearly showed that the reverse algorithm had a low false-positive rate and very few equivocal screening results but did identify previously undiagnosed late latent syphilis cases. PCR was more sensitive than both DF and IF microscopy for direct diagnosis and enabled monitoring for azithromycin resistance.

Syphilis in Ottawa: An evolving epidemic

Background

The incidence of infectious syphilis in Canada has declined throughout the latter decades of the last century; however, in Ottawa, an upsurge in new cases began in 2001. The local epidemic continues to involve predominantly gay, bisexual and other men who have sex with men (gbMSM), but in recent years, has expanded further into heterosexual populations. This has coincided with an increase in the number of pregnant women testing positive for syphilis on antenatal screening. The aim of this study is to understand the changing epidemiology in infectious syphilis cases diagnosed in Ottawa to strengthen primary care management and public health response.

Methods

Surveillance data from the Ontario Ministry of Health were used to describe the evolving epidemiology of infectious syphilis in the Ottawa region from 2010 to 2019, including a comprehensive chart review of cases from 2015-2019.

Results

The number of cases of infectious syphilis in Ottawa rose from 50 cases in 2010 to 171 cases in 2019. These rates were consistently high among males, and increased from 10.9/100,000 in 2010 to 30.9/100,000 in 2019. The rates among females, in comparison, increased from 0.4/100,000 in 2010 to 3.2/100,000 in 2019, with corresponding increases during antenatal screening (with no congenital syphilis cases to date).

Conclusion

As the syphilis epidemic continues to evolve in Ottawa, ongoing surveillance plays a crucial role. Public health resources must address the needs of populations already impacted but at the same time be flexible enough to respond to changes in trends and support clinicians providing care to populations where the epidemic is emerging.

Importance of Serological Tests in the Diagnosis of Asymptomatic Congenital Syphilis in Neonates: A Case Report

Introduction: Congenital Syphilis (CS) is caused by the vertical transmission of Treponema pallidum during pregnancy. Here, we describe a case of CS, diagnosed solely by serological tests. Case Presentation: The patient was a newborn with CS, whose mother was infected with Treponema pallidum at the gestational age of 16 - 20 weeks. However, the patient had no signs of early CS, such as low birth weight, nasal congestion, maculopapular rash, or hepatosplenomegaly. The histopathological features in both mother and neonate suggested syphilitic placentitis. Regarding the serological tests, a non-reactive Venereal Disease Research Laboratory (VDRL) test result and a reactive Treponema pallidum haemagglutination (TPHA) test result were reported. After establishing the diagnosis of CS, we initiated treatment with procaine penicillin G (50,000 U/kg body weight), which was injected intramuscularly once a day for 10 days. Six months after discharge, physical examinations showed normal findings and non-reactive results of VDRL and TPHA tests. Conclusions: It can be concluded that detailed history-taking and serological tests play a vital role in establishing the diagnosis of CS, particularly in patients with asymptomatic congenital syphilis. An early diagnosis of CS can guide clinicians to initiate a standardized treatment and improve patient outcomes.

TPPA titer as a new adaptation for early diagnosis of congenital syphilis: a retrospective analysis of observation over three years in Yunnan, China

Background

Early diagnosis of congenital syphilis (CS) is difficult. This study aimed to determine the serological response discipline of syphilis passive antibody (SPA) in infants born to mothers with syphilis and provide the basis for the early diagnosis of CS.

Methods

Thirty-three infants born to mothers with syphilis and six infants with CS were recruited. The toluidine red unheated serum test (TRUST) and Treponema pallidum particle agglutination (TPPA) titers were followed up after birth.

Results

The results showed that serological response in the serum of infants with the TPPA titer decreased threefold at 3rd month, or the titer dropped to a minimum of 1:40 at 9th month was SPA. The TPPA titer of 6 CS cases remained positive after 3-year follow-up, and the titer did not decline after treatment and maintained longer. The infants with TRUST titer ≥ 1:4 at birth were prone to become syphilis serofast, while TRUST titer < 1:4 turned to negative quickly.

Conclusion

In infants with SPA, the TRUST converted negative earlier than the TPPA. The lower the TPPA initial titer was, the shorter the seroreversion time required. The TPPA titer can be used to predict CS in infants born to mothers with syphilis.

Syphilis in during pregnancy: association of maternal and perinatal characteristics in a region of southern Brazil

Objective:

To analyze the prevalence of syphilis in during pregnancy and its association with socioeconomic characteristics, reproductive history, prenatal and labor care, and newborn characteristics.

Method:

A retrospective, cross-sectional study based on gestational and congenital syphilis reports. A (records) linkage was performed in the Brazilian databases: “Information System for Notifiable Diseases” (Sistema de Informação de Agravos de Notificação - SINAN); “Live Births Information System” (Sistema de Informação sobre Nascidos Vivos - SINASC); and “Mortality Information System” (Sistema de Informação sobre Mortalidade - SIM).

Results:

The prevalence of gestational syphilis was 0.57%. The following associations of syphilis in pregnancy were found: non-white skin color/ethnicity (PR=4.6, CI=3.62-5.76); low educational level (PR=15.4; CI=12.60-18.86); and absence of prenatal care (PR=7.4, CI=3.68-14.9). The perinatal outcomes associated with gestational syphilis were prematurity (PR=1.6 CI=1.17-2.21) and low birth weight (PR=1.6; CI=1.14-2.28). Two deaths from congenital syphilis, one death from another cause and five stillbirths were reported.

Conclusion:

The results signify a long way until reaching the World Health Organization’s goal of eradicating congenital syphilis.

Detección de Treponema pallidum subespecie pallidum para el diagnóstico de sífilis congénita mediante reacción en cadena de la polimerasa anidada

Introducción. La sífilis es una enfermedad producida por Treponema pallidum subespecie pallidum cuya incidencia mundial es de 12 millones de casos por año, aproximadamente; de estos, más de dos millones se presentan en mujeres gestantes, siendo la sífilis congénita la complicación más grave de esta infección en el embarazo.Objetivo. Detectar la presencia de T. pallidum subespecie pallidum en muestras clínicas para el diagnóstico de sífilis congénita mediante reacción en cadena de la polimerasa (PCR) anidada y determinar su concordancia con las pruebas serológicas.Materiales y métodos. Mediante PCR convencional y anidada, se amplificaron tres genes diana (polA, 16S ADNr y TpN47) y se confirmaron los productos de amplificación de los genes TpN47 y polA por secuenciación. Las pruebas serológicas empleadas fueron la VDRL (Venereal Disease Research Laboratory), la de reagina plasmática rápida (Rapid Plasma Reagin, RPR) y la de aglutinación de partículas para Treponema pallidum (Treponema pallidum Particle Agglutination Assay, TPPA).Resultados. La sensibilidad para la PCR convencional fue de 52 pg y, para la PCR anidada, de 0,52 pg. La especificidad con los iniciadores TpN47 y polA fue de 100 %; los resultados de la secuenciación mostraron una identidad de 97 % con T. pallidum. En 70 % de las muestras, los resultados de las pruebas serológicas y la PCR anidada concordaron.Conclusión. El gen TpN47 resultó ser el mejor blanco molecular para la identificación de T. pallidum. La PCR anidada se presenta como una alternativa de diagnóstico molecular promisoria para el diagnóstico de sífilis congénita.

Early Congenital Syphilis: Recognising Symptoms of an Increasingly Prevalent Disease

BACKGROUND

Congenital syphilis (CS) is an infectious disease resulting from transplacental transmission of Treponema pallidum spirochetes from an infected mother to fetus during pregnancy. While uncommon, CS has shown an increased incidence in Canada and the United States since 2001 and 2012, respectively.

CASE REPORT

We present the case of a 5-week-old female infant with blistering rash on the palms and soles. The infant displayed decreased movement of the left upper extremity, clinically consistent with Parrot pseudoparalysis. Cutaneous involvement was limited to few tan crusted papules on the palms and soles. Mother reported a "false-positive" result of rapid plasma reagin (RPR) testing at 31 weeks. Cerebrospinal fluid studies of the infant resulted with positive Venereal Disease Research Laboratory (VRDL) test and positive microhemagglutination assay (MHA-TP). Histopathology of a crusted papule revealed a lichenoid infiltrate composed of lymphocytes, histiocytes, and plasma cells. Immunohistochemical staining for T pallidum was negative. The patient completed treatment with a 10-day course of intravenous penicillin.

DISCUSSION

While CS is largely considered a historic entity, it has been increasing in incidence in the United States since 2012 and in Canada since the early 2000s. Diagnosis of CS can be difficult as infants may be asymptomatic or present with nonspecific signs. This case highlights the presentation of minimal cutaneous involvement as well as skeletal involvement after birth. RPR testing may result in false negatives or indeterminate results, further complicating diagnosis. Given these difficulties in screening and the increasing incidence of CS, clinicians may need to refamiliarise themselves with its clinical findings.

Contribution of a Comparative Western Blot Method to Early Postnatal Diagnosis of Congenital Syphilis

Serology has a pivotal role in the diagnosis of congenital syphilis (CS), but problems arise because of the passive transfer of IgG antibodies across the placenta. The aim of this study was to assess the diagnostic value of a comparative Western blot (WB) method finalized to match the IgG immunological profiles of mothers and their own babies at birth in order to differentiate between passively transmitted maternal antibodies and antibodies synthesized by the infants against Treponema pallidum Thirty infants born to mothers with unknown or inadequate treatment for syphilis were entered in a retrospective study, conducted at St. Orsola-Malpighi Hospital, Bologna, Italy. All of the infants underwent clinical, instrumental, and laboratory examinations, including IgM WB testing. For the retrospective study, an IgG WB assay was performed by blotting T. pallidum antigens onto nitrocellulose sheets and incubating the strips with serum specimens from mother-child pairs. CS was diagnosed in 11 out of the 30 enrolled infants; 9/11 cases received the definitive diagnosis within the first week of life, whereas the remaining two were diagnosed later because of increasing serological test titers. The use of the comparative IgG WB testing performed with serum samples from mother-child pairs allowed a correct CS diagnosis in 10/11 cases. The CS diagnosis was improved by a strategy combining comparative IgG WB results with IgM WB results, leading to a sensitivity of 100%. The comparative IgG WB test is thus a welcome addition to the conventional laboratory methods used for CS diagnosis, allowing identification and adequate treatment of infected infants and avoiding unnecessary therapy of uninfected newborns.

Current Perspectives on Prevention of Mother-to-Child Transmission of Syphilis

This article aims to provide an update on the prevention of mother-to-child transmission of syphilis by drawing upon some important basic concepts and reviewing the most recent literature on the diagnosis and treatment of syphilis in pregnancy. New technologies, such as automated and point-of-care immunologic tests, are shifting some paradigms, which will certainly be further investigated in the forthcoming years. This is the time to carefully evaluate traditional as well as new strategies to prevent congenital syphilis. Adverse outcomes of mother-to-child transmission of syphilis can be prevented with antenatal screening and penicillin therapy, which proved to have an excellent cost-benefit ratio even in populations with a low prevalence of syphilis. However, syphilis epidemiology is influenced by socioeconomic and cultural factors, and major challenges are faced by poor and developing countries in which the severity of the problem is extremely alarming. On the other hand, the emergence of new technologies has raised doubts about the best algorithm to be used when proper laboratory resources are available. Conditions are quite heterogeneous across populations, and some procedures should not be generalized while there is no evidence that supports some changes and while in-depth studies about local conditions are not conducted. Official organizations need to be alert in order to avoid isolated decisions and ensure that evidence-based guidelines be used in the management of syphilis in pregnancy.