STI prevention & management

This transcript is the automated English captions in the recordings. The text may not align with the audio, and there may be errors in the transcript.

Tom Lee: Okay, great. Well, hi everyone. thank you all for joining today's webinar.

My name is Tom Lee and I'm a policy analyst with the Public Health Agency of Canada. this webinar series is known as the communicable diseases and infection control webinar series and we're pleased to have you join us for today's webinar. As we join together virtually, I want to recognize the importance of the lands on which we find ourselves on. 

From coast to coast to coast, we acknowledge that we are on the traditional lands of the First Nations, Inuit, and Metis people. Let us collectively honor and cherish the spirit of reciprocity, cultivating a shared commitment to the respect and care of these lands for generations to come. A few notes for today's webinar. 

Following today's event, a copy of the presentation deck and recording as well as a feedback form will be sent to you. Your feedback will be greatly appreciated. This webinar will be conducted in English only. 

Simultaneous interpretation in French can be accessed through selecting the interpretation button in the menu at the bottom of your screen. Please take a moment to find that button if you would like to listen to the webinar in French. Your audio has been muted to reduce noise and video is disabled for this webinar. 

If you're having any technical problems and need help, you can reach us through the chat function. Feel free to communicate in either English or French. If you have a question for the presenter, please submit your question using the Q&A function and we will look to answer them during the panel discussion at the end of the webinar. 

Note, you may send check you may select send anonymously if you choose to not wish to have your information shared. and we will have all the questions allocated towards the end of the webinar. I will now welcome Dr. Andrea Chittle who will be the main speaker for today's webinar.  

Andrea Chittle: Thanks Tom. I'm just sorting out my settings. 

Okay, so hopefully folks are able to see me as well as my screen. so I'd like to take a moment to introduce myself. I'm joining from Guelph in Ontario. 

Guelph is located on the traditional lands of the Attawandaron, Anishinaabek and Haudenosaunee people, and on the treaty lands of the Mississaugas of the Credit. My training is in family medicine and public health and I am a medical advisor at the Public Health Agency of Canada. Much of my clinical work and my work at the Public Health Agency of Canada has focused on the prevention, detection, and management of sexually transmitted and bloodborne infections. 

After the presentation as relevant to your context, I hope that you will refer to and apply national advisory committee on sexually transmitted and bloodborne infection or NAC-STBBI screening recommendations for gonorrhea, chlamydia and syphilis. I hope you'll refer to and apply the interim recommendations for the treatment of uncomplicated gonorrhea infections. be able to explain the role of epidemiologic information, clinical exam findings and the interpretation of test results in the diagnosis of syphilis and also locate and use PHAC's sexually transmitted and bloodborne infections STBBI resources for health professionals. 

For my presentation today, I'm going to start by reviewing national level epidemiologic trends in chlamydia, gonorrhea, and syphilis. Then I'll use two case examples to highlight the NAC-STBBI's recommendations for chlamydia, gonorrhea, and syphilis screening, and gonorrhea and syphilis management in adolescence and adults. I'll also briefly mention the new doxycycline post-exposure prophylaxis, Doxy-PEP, recommendations when I review the first case and I want to acknowledge that the use of doxycycline as prophylaxis against bacterial sexually transmitted infections STI is an off label use of this drug. 

This means that health Canada has not approved the use of doxycycline for this indication.  

Oh, sorry. I'm seeing that there's a lot of echo. 

Might move it closer. Is that any better?  

Tom: Andrea, the audio sounds good. Thank you.

Andrea: Okay. throughout the presentation, I will share resources that PHAC has developed for health professionals, including some resources that include images of syphilis clinical exam findings. 

There are some quiz questions embedded throughout the presentation to hopefully make things a bit more interactive. and we should have at least 10 minutes at the end for Q&A. So to provide a bit of context for the recommendations that I'll review today, I'm going to highlight some national trends in chlamydia, gonorrhea, and syphilis. 

I adapted the next few slides with permission from another recent webinar. Chlamydia is the most reported notifiable disease in Canada and the most reported bacterial sexually transmitted infection by far. In 2023, nearly 130,000 cases of chlamydia were reported nationally for a total rate of 323 per 100,000 population. 

The rate of chlamydia has been increasing over the past 30 years. And over the past 10 years, from 2014 to 2023, the rate increased by 5%. Rates of reported chlamydia have consistently been higher among females than males, although the gap between female and male rates has been narrowing. 

Gonorrhea is the second most reported bacterial STI. In 2023, more than 42,000 cases were reported. The rate of gonorrhea has also been increasing over the past 30 years and has more than doubled over the last 10 years. 

In contrast to chlamydia, higher rates of gonorrhea are reported in males compared to females. The rate among males has been increasing more rapidly, widening the gap between the reported rate for males compared to females. For infectious syphilis in 2023, there were over 12,000 cases reported nationally, and that corresponds with a rate of 30.5 cases per 100,000 population. 

Syphilis rates have increased dramatically in recent years. In 2023, the national rate of infectious syphilis was more than four times the 2014 rate. And while a decrease was observed in 2023 compared to 2022, it's too soon to tell if this downward trend will continue. 

The map on the right side of the slide shows that infectious syphilis rates vary dramatically between provinces and territories in Canada. The prairie provinces and territories are disproportionately impacted by infectious syphilis. Manitoba, Yukon, Northwest Territories, and Nunavut all reported infectious syphilis rates higher than the national rate in 2023. 

The main part of the presentation today will use case examples to highlight guidance from PHAC for preventing and managing chlamydia, gonorrhea, and syphilis. PHAC provides public health guidance for the prevention and management of sexually transmitted and bloodborne infections. This guidance is developed in collaboration with an expert advisory committee, the NAC-STBBI. 

You can find the guidance in PHAC STBBI guides for health professionals online. This information is also available through a mobile app. And I just want to flag that there's often a bit of a delay between posting new content to the online version of the guides and updating the content on the mobile app. 

So for Doxy-PEP specifically, the recommended updates are pending in the mobile app and you should refer to the guides for the most current information at this time. The first quiz question should pop up for folks. And this may be a question that you've seen before if you've attended other webinars that I've delivered. 

but I think it's an important point to emphasize. If there are discrepancies between provincial, territorial, or local guidance and PHAC guidance for STI care, clinicians should follow provincial, territorial, or local guidance. And is that true or false? 

Okay. And so the large majority of people selected true, which is correct. Local, provincial, and territorial recommendations. 

Consider important factors that are relevant to your context, including epidemiologic trends and antimicrobial resistance patterns. So, if there is a discrepancy, you should defer to the local, provincial, or territorial recommendations. Today, my presentation is going to focus on PHAC guidance. 

The first case, Rick, is a fabricated case. So any similarities that you may notice between Rick and a real person are purely coincidental. As I go through the case, I'll review the NAC STBBI's chlamydia, gonorrhea, and syphilis screening recommendations for nonpregnant people. 

And I'll also highlight the committee's interim recommendation for treating uncomplicated gonorrhea infections. I'll also share some information about the new recommendations for Doxy-PEP, which as I mentioned is an off label use. Rick is a 27 year-old cisgender man. 

This means that Rick's assigned sex at birth was male and his gender identity is man. He uses the pronouns he him. Rick works as a computer programmer and his sexual partners are cisgender men. 

He has insertive and receptive anal and oral sex and has had five sexual partners in the last two months. He hasn't traveled outside of Canada recently. He shares that he has used shared bills when using inhaled substances and the most recent episode of using shared bills was one year ago. 

He doesn't have a history of tattoos or piercings from any unlicensed facilities. He's attending a follow-up HIV preexposure prophylaxis or HIV prep visit for a renewed prescription and STBBI screening. Rick was previously treated for secondary syphilis 2 years ago and his non-treponemal RPR titre has declined to a stable low level of 1. 

He has completed immunization series for hepatitis A, hepatitis B, HPV and MPOX. Rick is taking oral anti-retroviral medication for HIV prep and he doesn't have any known drug allergies. So, another quiz question should pop up for you. 

According to PHAC STBBI guides, how frequently should syphilis, gonorrhea, and chlamydia screening be considered for non-pregnant sexually active adolescents and adults who belong to population groups or communities experiencing a high prevalence of sexually transmitted and bloodborne infections? Should it be as often as every three months, every 3 to six months, every 12 months, or every 24 months? 

Okay, and so more than half of people selected answer A or the first answer which was as often as every 3 months with a significant number of people suggest selecting every 3 to 6 months. and I'll go through those recommendations. The top answer was the most correct. 

When I speak about screening, I'm referring to investigations aimed at detecting an infection in someone who doesn't have any symptoms. PHAC published updated syphilis screening recommendations for non-pregnant adolescents and adults in 2023. And on the screen right now is a screenshot of a double-sided infographic that we developed called Let's Talk About Syphilis. 

It summarizes current syphilis screening, treatment, and follow-up recommendations. The NAC-STBBI recommends screening all sexually active adolescence and adults with new and/or multiple partners and or upon request of the individual. The NAC STBBI recommends screening those with multiple sexual partners every 3 to 6 months. 

And when serving population groups or communities experiencing a high prevalence of syphilis, the NAC-STBBI recommends targeted opt out screening as frequently as every 3 months. Population groups and communities experiencing a high prevalence of syphilis include gay, bisexual, and other men who have sex with men, people living with HIV, people who are or have been incarcerated, people who use substances or addiction services, and some indigenous communities. PHAC published updated recommendations for gonorrhea and chlamydia screening for non-pregnant adolescents and adults in 2025 to prevent complications and sexual transmission. 

The NAC STBBI suggests screening sexually active persons younger than 30 years of age annually. For those with multiple sexual partners or a new partner since last testing, screening can be considered as frequently as every 3 to 6 months. And in addition, in populations or communities experiencing high rates of sexually transmitted and bloodborne infections, NAC- STBBI suggests opt out screening as often as every 3 months. 

And NAC STBBI encourages considering approaches to increase the uptake of screening like opportunistic screening and the use of strategies to increase the accessibility of and normalize testing like testing in outreach settings and the use of self-sampling for specimen collection. PHACs STBBI guides contain some pragmatic suggestions about pharyngeal and rectal screening for gonorrhea and chlamydia and I'm aware that extrogenital testing is not routinely available in some provinces and territories so practically this will have an impact on the ability to conduct these types of screening tests sight screening is recommended for individuals assigned female at birth who have performed oral sex. And for people assigned male sex at birth who have performed oral sex and who are at high risk of exposure, including gay, bisexual, and other men who have sex with men, GBMSM, those with multiple sexual partners and those with sex partners at high risk of infection. 

According to the STBBI guides, rectal sight screening is indicated for people who have a history of receptive anal sex regardless of condom use. and rectal screening is suggested for all GBMSM regardless of history of receptive anal sex. In general, chlamydia and gonorrhea testing can be done with culture and antimicrobial susceptibility testing or nucleic acid amplification testing, NAAT. 

The tests available may vary by anatomical site and by lab and they often change over time. So, it's important to verify with your lab. Generally NAAT is used for screening as it's more sensitive than culture. 

Urogenital gonorrhea specimens for NAAT can be a first void urine or urethral endocervical or self or clinician collected vaginal swab and as available self or clinician collected pharyngeal and rectal chlamydia and gonorrhea specimens can also be obtained for NAAT. When you're screening for gonorrhea, the NAC STBBI recommends collecting a specimen for both culture and NAAT. If you're screening someone who is a known gonorrhea contact in the context of sexual assault or abuse or if someone may have acquired a gonorrhea infection in an area with high rates of AMR in gonorrhea or antimicrobial resistance in gonorrhea. 

This slide does flag that we're aware of an error in the STBBI guides and we're in the process of correcting that. Routine collection of specimens for gonorrhea culture testing when you're screening prenatal patients is not indicated. You can screen with NAAT in the absence of symptoms or any of these other indications for culture. 

This is a summary of the results from Rick's complete STBBI screening panel. Gonorrhea was detected by NAAT on urine and throat specimens. Rick also had blood testing for HIV, syphilis, and hepatitis C. 

His HIV result is negative. As expected, his syphilis testing was positive with a reactive treponemal CMIA, reactive non-treponemal RPR result with a titre of one and reactive treponemal TPPA results. I will review syphilis testing and test interpretation when I discuss the next case. 

But as a sidebar, if Rick had a new syphilis infection, we would expect to see the non-treponemal RPR titre increase at least four-fold or two dilutions. So this would be to a titre of 1 to four or greater. Rick's hepatitis C antibody screen is negative. 

An additional caveat about gonorrhea culture testing. The NAC-STBBI advises that when a gonorrhea infection was detected using NAAT only, if feasible and if doing so would not delay treatment, collect a specimen for culture and antimicrobial susceptibility testing before administering treatment. Practically in Rick's case, I would likely collect a pharyngeal swab for culture and antimicrobial susceptibility testing before administering treatment, but I would only collect a urethral specimen if he was experiencing discharge because of the discomfort associated with such tests. 

And I would emphasize the importance of a test of cure. Another quiz question should show up for folks. According to PHAC STBBI guides, what is the interim preferred treatment for uncomplicated gonorrhea in individuals 10 years of age and older? 

Is it dual therapy with ceftriaxone 250 mg and 1 gram of azithromycin? Dual therapy with cefixime  800 mg and a gram of azithromycin. Monotherapy with ceftriaxone 500 mg. Monotherapy with azithromycin two grams or could you use all of the above as preferred treatment regimens? Okay. so the responses should show for folks as well I think and the correct answer was the third option which most people selected or just over half selected and that was monotherapy with ceftriaxone 500 milligrams intramuscular as a single dose. 

The NAC-STBBI's interim recommendation for treatment of uncomplicated gonorrhea was published in December 2024. Uncomplicated gonorrhea infections include infections that are localized to the urethra, cervix, rectal and or pharynx. And the preferred treatment for uncomplicated gonorrhea infections in adults and adolescents 10 years of age and older is now monotherapy with ceftriaxone 500 mg intramuscular as a single dose. 

This recommendation replaces the previous dual therapy recommended regimens and those included 250 mg of ceftriaxone in combination with a gram of azithromycin or 250 mg of ceftriaxone with doxycycline administered twice daily for 7 days. The NAC-STBBI does note that if you haven't ruled out co-infection with chlamydia at the time of treatment, you should also treat for chlamydia and that can be by adding oral azithromycin 1 gram as a single dose or doxycycline 100 mg twice daily for 7 days to the gonorrhea treatment regimen. In addition, the NAC STBBI recommends a gonorrhea test of cure for all positive sites in all cases. 

Test of cure is particularly important when a regimen other than monotherapy with ceftriaxone 500 mg was used for treatment. And I'll speak a bit more about test of cure considerations after I quickly go through the alternative treatments. The regimens listed here for pharyngeal and anogenital gonorrhea infections would primarily be considered when there's a strong rationale for oral over injection treatment. 

This could include if you're working in treatment facilities that don't have injection capabilities or when caring for patients who decline an injection. The currently published alternatives vary by sight of infection because pharyngeal infections are more difficult to eradicate and because of concerns about high rates of tetracycline class antibiotic resistance in gonorrhea. The regimen containing doxycycline is not a listed alternative for treating pharyngeal gonorrhea infections. 

The STBBI Guides list additional alternatives for consideration when patients have contraindications to cephalosporins, or contraindications to cephalosporins and macrolides. As I mentioned, the NAC STBBI recommends gonorrhea test of cure for all positive sites in all cases. Ideally, gonorrhea test of cure samples should be collected for both culture and NAAT, but there are some considerations to bear in mind about the timing of each of these test types. 

Specimens for culture testing should be delayed until at least 3 days after treatment completion and specimens for NAAT should be delayed until at least 3 to four weeks after treatment completion. So if an individual returns for test of cure within 3 weeks after treatment was completed, the initial test of cure should be with culture. Ideally, assuming the culture was negative to complete their follow-up, a subsequent additional test of cure with NAAT should be conducted at least 3 to 4 weeks after treatment was completed. 

If someone returns for test of cure more than 3 weeks after treatment was completed, both NAAT and culture can be collected at that time. So, returning to our case, Rick comes back. Oh, sorry. 

I'll wait for it to show up on everyone's screen. Getting excited. Rick returns for test of cure 4 weeks after treatment with ceftriaxone 500 mg administered intramuscularly as a single dose. 

Which tests would be appropriate for tests of cure? Urethral swab for gonorrhea culture, urine for gonorrhea NAAT, pharyngeal swab for gonorrhea culture, pharyngeal swab for gonorrhea NAAT or all of the above. Okay. 

And so most people 63% of people selected the last response all of the above. and that is the correct answer. However, practically as with testing prior to treatment, I would likely personally not collect a urethral specimen for urethral culture if Rick did not have symptoms that at that time because of the discomfort associated with collecting such a specimen. 

So Rick's urine NAAT and pharyngeal NAAT and pharyngeal culture results indicate that the infections in those sites were cured. And when you're reviewing those results with him, Rick asks about doxycycline postexposure prophylaxis Doxy-PEP. Another question for people to consider. 

This one's true or false. Considering baseline rates of tetracycline resistance in gonorrhea in Canada, Doxy-PEP may be less effective for preventing gonorrhea compared to syphilis and chlamydia. and 82% of people selected true for that question, which is correct. 

In November 2025, PHAC published new NAC-STBBI recommendations on the use of Doxy-PEP. These recommendations answer the first of four guideline questions that the NAC-STBBI prioritized related to the use of doxycycline for the prevention of bacterial STI. And that question is should Doxy-PEP or standard care be used in cisgender GBMSM and transgender women at risk of chlamydia, gonorrhea, or syphilis infection. 

So because of the question that these recommendations are answering, the recommendations focus on cisgender GBMSM and transgender women. Importantly, these are the groups for whom there is currently the most high quality evidence about the intervention. Presently, the NAC STBBI does not have recommendations for Doxy-PEP for other population groups and there are no recommendations for doxycycline pre-exposure prophylaxis Doxy-PrEP. 

The NAC-STBBI recommends considering Doxy-PEP for cisgender, gay, bisexual, and other men who have sex with men who are at increased risk of bacterial, sexually transmitted infections as part of comprehensive STBBI services to reduce the risk of syphilis, chlamydia, and possibly gonorrhea. In addition, the NAC-STBBI recommends discussing personal, community, and population level risks of antimicrobial resistance with individuals considering Doxy-PEP to inform shared clinical decision-making about its use. Remarks accompany each of these recommendations. 

They explain the recommendation and describe relevant considerations to support health professionals in incorporating the Doxy-PEP recommendations into their practice. We developed a double-sided quick reference docent. It summarizes the recommendations and includes details from the remarks. 

The first Doxy-PEP recommendation refers to comprehensive STBBI services. So I want to step back for a moment to conceptualize STBBI prevention more broadly. This slide depicts the range of effective STBBI prevention methods as tools in a figurative toolbox. 

STBBI prevention methods reduce the risk of acquiring STBBI and or the impact and spread of STBBI. While some tools like education and vaccination against hepatitis B have broad use and benefit, others like harm reduction and vaccination against MPOX are strategies that have particular relevance and benefit for certain individuals and communities. Generally the prevention methods complement each other and a comprehensive STBBI approach will incorporate all relevant tools. 

For this illustration and in PHAC STBBI guides we've used the term biomed interventions to describe a category of prevention tools that includes vaccinations and therapeutics used as pre and postexposure prophylaxis for HIV and bacterial STI. The methods that are highlighted here are the ones that are particularly relevant for our case, Rick. In most clinical settings, addressing all relevant tools in a single visit is not practical. 

In reviewing this case today, I highlighted bacterial STI screening and Doxy-PEP. After discussing the possible benefits and drawbacks of Doxy-PEP, Rick decides that he would like to use it. He's given a prescription that includes detailed instructions for using Doxy-PEP. 

These details are covered in the infographic that I shared. Rick is advised to continue regular STI screening and seek testing if he notices symptoms that could be an STI. Some important points that I hope you'll take away after reviewing this case are summarized on this slide. 

The NAC-STBBI suggests opt out screening for syphilis, chlamydia, and gonorrhea as frequently as every 3 months in populations or communities experiencing a high prevalence of STBBI. The preferred treatment of uncomplicated gonorrhea is with ceftriaxone 500 mg intramuscular as monotherapy and cure should be confirmed ideally with both culture and that off label use of Doxy-PEP can be considered as a component of comprehensive STBBI care for cisgender GBMSM and transgender women increased risk of bacterial STI to prevent syphilis, chlamydia and possibly gonorrhea. Health professionals should discuss the potential AMR risks of Doxy-PEP with patients considering its use. 

The second case, Anna, is a two-part case. The first part is fabricated and the second is adapted from a published case. The first time you meet Anna, she's 21. 

She's a cisgender woman. This means that she was assigned female sex at birth and her gender is woman. She uses she her pronouns. 

Her sexual partners are cisgender men, meaning that they were assigned male sex at birth, and their gender is man. Anna has receptive vaginal, anal, and oral sex. She has had one sexual partner in the last 2 months, and she hasn't recently traveled outside of Canada. 

She's presenting for a first prenatal visit. By her last menstrual period, gestational age is estimated to be 7 weeks and 1 day. She doesn't have any significant past health history and is not taking any prescription medications. 

She doesn't have any known drug allergies. Another poll question. According to PHAC STBBI guides, when should prenatal screening for syphilis be conducted? 

During the first trimester or at the first prenatal visit. At 28 to 32 weeks if at ongoing risk and in areas experiencing outbreaks. At delivery if at ongoing risk and in areas experiencing outbreaks more frequently if at ongoing risk all of the above. 

Okay. and it looks like oh my my screen was doing something funny there so I couldn't see that most people 90% selected all of the above which is the correct answer. This is the same Let's Talk about Syphilis infographic that I previously shared. 

The NAC STBBI has prioritized review of recommendations for syphilis screening in pregnancy. Currently, PHAC guides recommend screening pregnant individuals for syphilis in the first trimester or at the first prenatal visit. In areas with outbreaks and for people at ongoing risk of infection, screening should be repeated between 28 and 32 weeks gestation and again during labor. 

And I understand that the guidance for prenatal syphilis screening varies between provinces and territories. As I mentioned, where there are differences between PHAC guides and provincial, territorial, or local recommendations, you should follow provincial, territorial, or local recommendations because those consider relevant contextual factors. In 2023, PHAC published updated screening recommendations for urogenital chlamydia and gonorrhea during pregnancy. 

We developed an infographic to summarize those recommendations and a section of that resource is showing is showing on this slide. As with syphilis, initial screening for gonorrhea and chlamydia is advised during the first trimester or at the first prenatal visit. For gonorrhea and chlamydia, repeat prenatal screening is suggested for everyone in the third trimester. 

And in addition, screening at the time of labor is suggested if no prenatal screening has occurred, including no third trimester screening or if follow up of a positive chlamydia or gonorrhea result during pregnancy was not completed. As for non-pregnant people, urogenital gonorrhea and chlamydia screening can be done using NAAT and either a urine, vaginal or endocervical specimen can be collected and the same indications for collecting a specimen for gonorrhea culture apply for pregnant as for non-pregnant people. To reiterate, the NAC STBBI recommends collecting a specimen for culture and antimicrobial susceptibility testing along with a specimen for NAAT if you're screening someone who is a known gonorrhea contact in the context of sexual assault or abuse or for someone who may have acquired an infection somewhere with high rates of antimicrobial resistance in gonorrhea. 

So Anna collected a vaginal self swab for chlamydia and gonorrhea NAAT and blood testing was submitted for syphilis and all of these results were negative. 8 years later Anna presents to care as a syphilis contact. She discloses that she is pregnant with an uncertain last menstrual period and no prior prenatal care in this pregnancy. 

This is her fourth pregnancy and her three children were born at term by spontaneous vaginal deliveries. In the years since she was last seen, she has not been diagnosed with any new medical conditions and she is still not taking any prescription medications and has no known drug allergies. Anna hasn't noticed any signs or symptoms of a syphilis infection. 

Her neurological exam, including cranial nerve exams and balance and coordination testing, are all normal. There is a painless shallow vulvar lesion at the bottom of the opening of the vagina with associated bilateral inguinal lymphadenopathy. No other abnormal skin or mucosal lesions are noted. 

Her uterine fundus is palpable 2 cm below the umbilicus suggesting a pregnancy that is around 18 weeks gestation and fetal heart sounds are detected at a rate of 140 beats per minute. Another poll question. Given the information available to you, how would you clinically stage an syphilis infection? 

It be primary syphilis, secondary syphilis, early latent syphilis, late latent syphilis, or are laboratory tests required to clinically stage an syphilis infection? Okay. And so we have about two thirds of people selecting the first answer, primary syphilis, and about a third of people thinking that maybe lab tests are required to conduct clinical staging. 

In this case, given the information that you have that Anna is a contact of syphilis and in the context of characteristic findings of primary syphilis, you could clinically stage this infection as primary syphilis. So the first answer is most correct. This is a screenshot of a resource that's included in a visual staging guide for syphilis that PHAC developed. 

The infographic highlights clinical exam findings that can support staging a syphilis infection. In general, diagnosing syphilis involves combining test results with a clinical staging assessment. Syphilis has been referred to as the great impersonator because it has so many manifestations. 

Syphilis infections progress through stages. The primary, secondary, and early latent stages are also referred to as infectious syphilis because of the higher risk of syphilis transmission during these stages. Individuals may have characteristic symptoms or experience non-specific symptoms or not notice any symptoms at all. 

In some cases, characteristic features of a syphilis infection are only discovered during a comprehensive clinical exam that is performed to assess someone who is a contact of syphilis or has reactive serological test results. Importantly, the stage of infection informs decisions about treatment, follow up, and contact tracing. The hallmark of primary syphilis is the chancre, which often goes unnoticed by patients. 

Signs and symptoms of secondary syphilis can develop as the chancre is resolving and can include constitutional symptoms and a body rash. Latent syphilis is not associated with any signs or symptoms. Early latent syphilis spans the first year after infection and late latent syphilis is an infection lasting longer than one year. 

Early and late neurosyphilis can also occur. The visual staging guide contains images of characteristic features of syphilis infections. And this slide depicts the common features of primary syphilis which typically begins the chancre typically begins as a solitary painless papule at the site of inoculation which could be genital, perianal or oral. 

The papule then ulcerates and appears as a one to two cm round lesion with a raised inderrated margin and non-oozing base. Multiple shankers can occur particularly in the context of HIV and there can be associated regional lymphadenopathy. Tests for syphilis include the suite of tests generally processed in medical labs like conventional serologic tests, direct tests from rashes or lesions and tests performed on cerebral spinal fluid. 

In addition, four point of care tests have been licensed for use in Canada in the last few years. In general, conventional serologic tests are used for syphilis screening. Serologic testing follows an algorithm that includes treponemal tests and non- treponemal tests and I'll share a diagram of the reverse algorithm which I understand is the process used in Manitoba, Yukon, Northwest Territories and Nunavut on the next slide. 

Treponemal tests are for antibodies against Treponema pallidum and the results are usually reported as reactive or non-reactive. Once someone has had a syphilis infection, these tests generally remain reactive for life. Non-treponemal tests are tests for other antibodies and these results are reported as titres, numerical ratios which generally decline after time over time and after treatment. 

They can become negative after treatment and in some untreated late syphilis infections. In some cases non-treponemal titre test results remain at a stable usually low level after treatment. These tests are less likely to become negative after reinfections. 

There are also direct tests that can be performed on samples from rashes or lesions that are concerning for syphilis, including PCR tests. Point of care tests for syphilis may detect treponemal and/or non-treponemal antibodies. And I won't get into any more detail about those for reasons of time, but the ones highlighted in green are currently approved. 

And dual treponemal non-treponemal test is currently only approved in Canada for investigational purposes. This diagram depicts the reverse algorithm for syphilis serologic testing. In the reverse algorithm, the first test is a non-treponemal test, usually CMIA or EIA. 

If that test result is reactive, confirmatory testing is then done. Most commonly the non-treponemal RPR test is the second test performed. Additional confirmatory tests may be done often with the TPPA which is another treponemal test. 

And this table shows some common combinations of syphilis serologic results. Someone who has not had a syphilis infection previously will generally have a non-reactive screening test result. It is possible to have non-reactive treponemal test results in the weeks after an exposure. 

So if there are clinical or epidemiologic risks for syphilis and initial testing is negative that testing should re be repeated in 2 to 4 weeks. Someone who has infectious syphilis will generally have a reactive screening non-treponemal test result along with reactive treponemal test results. The image on the right side of this slide is a depiction of a manual RPR test where the RPR titre is 1 to 8. 

And this test involves mixing a standardized suspension of antigen with the specimen if there are no antibodies to the RPR antigen in the specimen. A uniform gray mixture appears and the result is reported as non-reactive. If antibodies to the antigen are present in the sample, the antigen and antibodies combine and they glutenate and appear as black dots on the card. 

The specimen is then diluted successively and mixed with the antigen until no dots can be visualized. And the last dilution for which dots are evident is reported as the titre. A higher titre thus indicates more dilutions were required and that there were more antibodies present in the sample. 

And usually a titre equal to or greater than 1 to 8 is considered to be a high titre and suggestive of infectious syphilis. There are a few possible interpretations. If someone has a reactive screening treponemal test result and non-reactive non-treponemal and treponemal confirmatory test results, it could be a false positive or it could indicate early previously treated or late latent syphilis. 

If the individual may have an early syphilis infection, repeat the testing in four weeks. And for individuals with reactive initial and confirmatory treponemal test results and non-reactive non-treponemal test results, they likely have recent or prior syphilis. So returning to our case, Anna's investigations are summarized here. 

Her ultrasound confirms a singleton pregnancy at 18 weeks and 2 days gestational age with no abnormalities reported. Her syphilis test confirmed the clinical diagnosis of primary syphilis. There was PCR testing done of the vulvar lesion and it detects treponemal palladium which confirms that the lesion was a chancre. 

And her serologic test results are also consistent with an early syphilis infection with a reactive treponemal and non-treponemal test result. Her RPR titre is quite high at 1 to 64 dilutions. So how would you treat an syphilis infection? 

And I'll give a moment for that to pop up. Would you treat with a single dose of benzathine penicillin G long acting 2.4 million units administered intramuscularly? Would you give weekly doses of benzathine penicillin G long acting 2.4 million units? 

Would you for two doses? Would you use doxycycline 100 milligrams twice daily for 14 days or doxycycline 100 milligrams twice daily for 28 days or would you choose one of the top two regimens the benzathine penicillin long acting regimens whatever is recommended by local experts and so there's quite this is a wider split than we've seen with some of the other questions about a third of people pick the each of the top two answers and about a third of people picked the final answer. and I would say that all of those actually are correct. 

The final one is the most correct. there is some variability in terms of the recommendations for managing syphilis, infectious syphilis in pregnancy. and some individuals do recommend two doses of benzathine penicillin g long acting. 

and some people recommend one. So, the first, the second, and the final answer were all correct. This slide is just another section of the let's talk about syphilis infographic. 

The PHAC guides recommend managing syphilis in pregnancy in consultation with an obstetric or maternal fetal specialist. And I know that this level of specialist or sub specialist support is not available in all areas and health professionals then are encouraged to consult with colleagues who are familiar with the management of syphilis in pregnancy. and we reviewed the recommendations for one or two doses of benzathine penicillin G long acting. 

Ultimately there is no satisfactory alternative to penicillin for the treatment of syphilis in pregnancy. The Jarisch-Herxheimer reaction is an acute febrile reaction that can occur after the administration of penicillin for the treatment of syphilis most often secondary syphilis. It's generally a self-limited reaction and can be managed with over-the-counter antipyretics. 

People may notice fever, chills, myalgia, arthralagia, headache, and in the context of secondary syphilis, possibly an exacerbation of rash. In pregnancy, this reaction can be more consequential as it has been associated with fetal distress and premature labor. While high rates of the reaction in pregnancy are reported in the medical literature, recent published case series from Alberta and Manitoba found the reaction to be relatively uncommon and all reactions in those case series were mild. 

in general, follow institutional protocols for inpatient versus monitored management of individuals who are being treated for syphilis in pregnancy. The syphilis toolkit contains a simplified algorithm for clinical staging. This is an updated version of an algorithm previously developed by members of the NAC-STBBI. 

It aims to support the staging and treatment of primary, secondary, and latent syphilis infections. It doesn't include any alternative treatments. The boxes that are in yellow on this slide highlight the inputs related to Anna's clinical scenario. 

And this is a screenshot of another section of that let's talk about syphilis infographic and reviews the followup of syphilis. Serial non-treponemal titres are used to confirm that syphilis treatment has been effective and in general those titres should be followed until they've reverted to a non-reactive result or a stable low level of 1 to four or lower. Documenting the lowest follow-up titre can support the detection of reinfections. 

and this slide also highlights the frequency of monitoring for individuals who are pregnant as well as trace back period for sexual contacts which varies by stage. The decline in non-treponemal titres following successful treatment varies depending on the stage of infection at the time of treatment, the titre at the time of treatment and whether the individual has been previously treated for syphilis. In primary syphilis, the guides indicate the titre should decline at least fourfold or become non-reactive by six months after treatment and eight-fold or become non-reactive by 12 months after treatment. 

The diagram on the right side of the slide depicts two examples of a four-fold or two dilution decline in titre. And you can use division of the denominators to determine how many folds the titre has changed by. So, as you can see, a change from 1 to 32 to 1 to 8. 

32 / 8 is a four-fold change or it's a two dilution change. Another poll question. Anna's baseline titre for this case was 1 to 64. 

What follow-up titres would indicate an adequate treatment response 6 months after treatment? Okay. and about half of people selected all of the above which is the correct answer. 

So for Anna whose baseline titre was 1 to 64, we want to see at least a four-fold decline in titre by 6 months. And so this would be to a titre of 1 to 16 or lower. and so all of those are 1 to 16 or lower. 

And I won't reiterate the messages that are the main messages from this portion of the presentation because I would like to leave a few moments for questions. PHAC has published community focused syphilis and HIV resources in eight indigenous languages and you can download these and obtain print copies from CATIE's ordering center. And so my apologies in advance. 

We don't have what I'd hoped we would have at the end. but hopefully we can answer a few of the questions that folks asked. Perfect. 

Tom: Thanks so much Andrea for the great presentation. we do have a few more minutes available for the Q&A. So there are questions that are coming in to us and we'll get started. 

Andrea, I have a first question here regarding Anna's case study. it's not always feasible to perform an invasive exam on clients depending on the healthcare setting. So how would a health care practitioner determine an syphilis stage if they did not observe the chancre? 

Andrea: Yeah, that's a a great question and of course very practically relevant. from my perspective working in public health clinical settings, it's super important for us to accurately stage syphilis infection so that we know that we've administered the correct treatment and so that we can be confident that we've seen an adequate decline in titre because that can change depending on the stage. so wherever possible and using any mechanisms means available to you I would really recommend doing that complete head-to- toe exam for your patient so that you're ensuring that they're getting appropriate antibiotics and that that we know that we are documenting an adequate response to treatment. 

the patient may often not notice something like a chancre. So, of course, that would only be discovered through a complete physical examination. Perfect. 

Tom: Thank you for that answer. this one's more of a logistical question, but ceftriaxone is currently supplied as 250 milligrams intramuscular vials. Will Canada have access to 500 mgram vials to reflect the new recommendations from PHAC? 

Andrea: thanks for that question. Health Canada is responsible for licensing drugs for use in Canada and drug companies apply to have their products approved. I'm not aware of any companies applying for approval for the 500 mgram formulation, but there is a little section in the statement about the gonorrhea treatment recommendations that lets people know that you can combine two 250 mgram vials into a single dosage. 

So you would use double the diluent which in my setting we use plain lidocaine and so we use 1.8 cc's of plain lidocaine with the two vials of 250 mg of ceftriaxone. 

Tom: Okay, perfect. I think we have time to squeeze in maybe one or two more questions. 

some people with a history of syphilis serif at 4 to eight dilutions. Why would some people see fast at a higher level? 

Andrea: Yeah, that's a great question as well. Thanks for asking that. It can be really variable between individuals. we know that people who have reinfections are less likely to have their non-treponemal titre revert to non-reactive. 

In my clinical setting, I've seen individuals be zero fast at 1 to 32. And my training was always if you see somebody who appears to be ser at 1 to eight or above, you should really be doing a lumbar puncture to confirm that the individual doesn't have a neurosyphilis infection. so that's a learning that I've incorporated into my practice. 

 just to make sure that that's not the case for someone who has a persistently high titre. But if someone had quite a high titre at baseline, then they may not revert to non-reactive. in pregnancy there can be a lag in sort of the decline of titre. 

So there's sort of different factors that can contribute to that. but in general we hope that you see a decline and if you're not seeing an appropriate decline in titre, it raises questions about could the individual have been reexposed? Was the treatment appropriate for the stage or was the staging perhaps not correct and they actually need a longer duration of therapy or is there a neurosyphilis infection that's been missed? 

Tom: Okay, perfect. I know we are at time. We're just going to squeeze in one last question here. 

For those who you feel are high risk for not following up, are there recommendations for treatment prior to labs? 

Andrea: I'm trying to think of what is in the guides. we there definitely in the guides is a recommendation to think about empiric therapy for somebody who is a recent i.e. within the last 90 days contact sexual contact of someone who has infectious syphilis. so then you would be treating somebody as if they also have infectious syphilis while waiting for their lab results. if you see somebody and you think that based on the clinical findings, they have a rash, they are part of a population group that you know is at higher risk for syphilis, you could draw serologic testing at the same time as initiating your empiric treatment for secondary syphilis. 

that would be a very clinically reasonable thing to do. But drawing that blood work as much as feasible is a is really important to do because you want to capture what their titre is so that you can do followup. Hopefully you're able to do that. 

 and so that you can docent reinfections if those occur. So if you don't have titres, you're not able to follow titres, then documenting and detecting reinfections and then managing patients down the road becomes quite challenging. 

Tom: Perfect. Thanks so much Andrea. we are past time for today's webinar. So, I just like to thank Andrea again for the wonderful presentation. 

We hope that you've had a chance to learn some really great insights and use the case study examples as a way to apply the guidelines into practice. as next steps, we will share a copy of the slide deck as well as the recording for today's webinar. a feedback form should be coming to you once you have left the webinar. 

And if you have any follow-up questions, feel free to contact us via email, which we have included in the chat. otherwise have a wonderful rest of the day and thank you so much for joining us.