The Call-On-Doc Guide to Syphilis

Syphilis is spread when the bacterium Treponema pallidum enters the body through a break in the skin or comes into contact with the mucous membranes. (6) The primary mode of syphilis transmission is from an infected male to another man or woman. (4) More specifically, sex through the following methods has been recorded as the primary mean of spread: 

• Anal: ​​Syphilis is transmitted through anal sex when an individual engages in unprotected anal intercourse with an infected male partner. During this sexual activity, the bacterium Treponema pallidum can be passed from the infected person's genital sores, skin rashes, or mucous membranes into the anal mucosa of the uninfected partner. The anal mucosa is a thin, delicate lining that covers the inner surface of the anus, and it can be easily susceptible to infections. Once the bacterium enters the body through small tears or abrasions in the anal mucosa caused by the sexual activity, it can establish an infection, leading to the development of syphilis. (8)
• Oral: Syphilis transmission through oral sex can occur when an individual engages in oral contact with the genitals, anus, or mouth of an infected partner of either sex. Treponema pallidum can be present in the genital sores, skin rashes, or mucous membranes of the infected person. During oral sex, if the mucous membranes or tiny cuts in the mouth or throat come into contact with the infected areas, the bacterium can enter the body and establish an infection. Similarly, if an individual with syphilis has oral sores or lesions, the bacterium can be passed to the mouth or throat of their partner during oral contact. (4)
• Vaginal: Syphilis is transmitted through vaginal sex when an individual engages in intercourse with an infected partner. The syphilis-causing bacteria can be present in the genital sores, skin rashes, or mucous membranes of the infected person. During vaginal sex, if the mucous membranes or tiny cuts in the genital area or surrounding skin come into contact with the infected areas, the bacterium can enter the body and establish an infection. Similarly, if a person with syphilis has sores or lesions on their genitals, the bacterium can be passed to their partner during sexual contact. (4)

Even in the absence of visible sores, an infected person, regardless of gender, who engages in kissing or sexual interactions with an uninfected individual of any gender, still poses a significant risk of transmitting syphilis. Syphilis can be present in the body even without showing external symptoms, particularly during the early stages of infection. 

While not as common, syphilis can indeed spread non-sexually through multiple means. Put simply, the bacteria only needs to gain entry to an uninfected person’s mucus membranes or bloodstream to infect them with the STI. The following examples are the most common means of non-sexual syphilis transmission: 

• Accidental Exposure: Accidental exposure to syphilis occurs when an individual inadvertently comes into contact with infected blood or bodily fluids in situations outside the traditional healthcare setting. While rare, such instances may arise in various occupational or non-medical scenarios. For instance, healthcare workers and laboratory personnel face the potential risk of accidental needlesticks or exposure to infected blood while handling samples or conducting tests. Emergency responders, including paramedics and first aid providers, might encounter situations where they inadvertently come into contact with the blood or bodily fluids of an infected individual while administering medical assistance. Additionally, community accidents, such as road collisions or physical altercations, could lead to accidental exposure to syphilis if the blood or bodily fluids of an infected person come into contact with broken skin or mucous membranes of others. 
• Blood Transfusion: Blood transfusion as a mode of syphilis transmission involves the inadvertent transfer of the bacterium Treponema pallidum from an infected donor's blood to a recipient during a blood transfusion. While the risk of syphilis transmission through blood transfusion is low in developed countries due to stringent blood screening measures, it remains a noteworthy concern in areas with limited resources or less robust screening protocols. The transmission can occur if the donor is in the early stages of syphilis, where the bacterium might be present in their bloodstream despite the absence of visible symptoms.
• Sharing Contaminated Needles: Sharing contaminated needles is a significant mode of syphilis transmission, particularly among individuals who engage in intravenous drug use. When people inject drugs using shared needles or syringes, they create a direct pathway for the bacterium Treponema pallidum to pass from an infected person's bloodstream to that of an uninfected individual. Syphilis is just one of several sexually transmitted infections and blood-borne diseases that can be spread through needle-sharing practices.
• Mother-to-child Transmission: Vertical transmission occurs when an infected pregnant woman passes the bacterium Treponema pallidum to her unborn child during pregnancy or childbirth. This mode of transmission poses severe risks to both the mother and the baby. If left untreated, syphilis can lead to serious complications during pregnancy, such as miscarriage, stillbirth, premature birth, or the birth of a baby with congenital syphilis. Congenital syphilis occurs when the bacterium crosses the placenta and infects the developing fetus, leading to a wide range of health problems, including developmental delays, physical abnormalities, and organ damage.

Syphilis has stages due to the progressive nature of the infection caused by the bacterium Treponema pallidum. As the infection develops, the bacterium spreads throughout the body, causing a series of distinct clinical manifestations. The stages of syphilis help categorize the various signs and symptoms that individuals may experience at different points during the course of the infection. 

• Primary Stage: The primary stage of syphilis typically begins with the appearance of a single, painless sore known as a chancre. The chancre is the initial sign of infection and develops at the site where the bacterium Treponema pallidum entered the body through sexual contact or direct contact with infected skin. Chancres can vary in size and may be located on or around the genitals, anus, mouth, or other parts of the body. They are usually firm and round with a clean base and can last for 3 to 6 weeks. Chancres often go unnoticed or are mistaken for other harmless skin conditions, which can lead to delayed diagnosis and treatment.
• Secondary Stage: If syphilis remains untreated, the infection progresses to the secondary stage, which typically occurs a few weeks to several months after the primary stage. During this stage, individuals may experience a variety of symptoms. One of the main signs is a rash that can develop on different parts of the body, but it is commonly seen on the palms of the hands and soles of the feet. The rash may be reddish-brown or copper-colored and can be accompanied by other symptoms such as fever, sore throat, swollen lymph nodes, fatigue, and muscle aches. The rash can be patchy and can come and go over several weeks, making it challenging to distinguish from other skin conditions.
• Latent Stage: After the secondary stage, syphilis enters a latent stage. In this stage, the visible symptoms disappear, and individuals may not experience any noticeable signs of infection. Latent syphilis can last for years, during which the infection is still present in the body but is considered "hidden" or "dormant." Despite the lack of symptoms, the infection can continue to progress and cause damage to internal organs, especially during the early part of this stage. At this point, the sores may heal and disappear, heavily reducing the chance of passing on the infection, but that does not mean there is a chance for it to be cured naturally. 
• Tertiary Stage: If syphilis remains untreated for a prolonged period, it can progress to the tertiary stage, which is the most severe and potentially life-threatening phase of the infection. Tertiary syphilis can occur many years after the initial infection. During this stage, the bacterium can cause severe complications, including cardiovascular problems such as aortic aneurysms and aortic regurgitation, neurological disorders like neurosyphilis, gummatous lesions (soft, tumor-like growths), and destructive bone and skin lesions. Tertiary syphilis can lead to irreversible damage to various organs and systems in the body, and it poses significant health risks if left untreated.

The likelihood of asymptomatic syphilis can vary depending on several factors, including the stage of the infection and the infected individual’s immune response. During the primary stage of syphilis, many will have visible symptoms, such as the appearance of a chancre (sore) at the site of infection. However, due to how there is little feeling to the sore itself, many do not notice the symptom until the condition progresses. This leads to a condition known as "unrecognized" or "hidden" primary syphilis.

The chances of experiencing syphilis symptoms tend to be high when the STI progresses to the second stage, which causes both rashes and some flu-like symptoms that are harder to ignore. Many people with syphilis do not seek testing or treatment due to the latent stage, where many individuals do not experience any noticeable symptoms. Latent syphilis can last for years, and it is essential to note that asymptomatic individuals can still transmit the infection to others.(9)

However, asymptomatic syphilis is not typical in the fourth stage, also known as the tertiary stage, of the infection. By the time syphilis reaches the tertiary stage, which can occur many years after the initial infection, the bacterium Treponema pallidum has caused extensive damage to various organs and systems in the body. During this stage, individuals are more likely to experience severe and potentially life-threatening complications, such as cardiovascular issues, neurological disorders, gummatous lesions (soft, tumor-like growths), and destructive bone and skin lesions. While some symptoms in the tertiary stage can be subtle or easily mistaken for other medical conditions, the progression of the infection often results in visible and noticeable signs of the disease that tend to push infected individuals to a medical provider. 

The most common and reliable way to diagnose syphilis is through a rapid plasma reagin or "RPR" test. The RPR test is a nontreponemal test, meaning it does not directly detect the bacterium itself that causes syphilis but rather identifies antibodies that the body produces in reaction to the infection. 

During a syphilis infection, the body generates specific antibodies called reagins, which are a type of non-specific antibody produced in response to the presence of the syphilis bacterium. The RPR test works by mixing a small sample of the patient's blood with cardiolipin, a substance found in the heart muscle of cattle. The cardiolipin is combined with charcoal particles to create the RPR test card. If the patient's blood contains syphilis antibodies (reagins), they will react with the cardiolipin on the test card, causing visible clumping or agglutination. The degree of agglutination is then measured and provides an indication of the amount of antibodies present in the blood.

The RPR test is commonly used as a screening tool for syphilis because it is relatively quick and easy to perform. However, it is a screening test and not a definitive diagnosis. If the RPR test yields a positive result, a confirmatory test, such as a treponemal test, is typically conducted to confirm the presence of syphilis antibodies and confirm the diagnosis. As per CDC regulations, each positive syphilis test must be reported to the state government.

Yes, it is possible to have a false-positive result for syphilis during testing. A false-positive occurs when the test indicates the presence of syphilis antibodies or the bacterium Treponema pallidum, even though the individual does not actually have the infection.

Several factors can contribute to false-positive syphilis test results, including:

• Cross-Reactivity: Some conditions or infections can lead to cross-reactivity with the antibodies tested in syphilis screening. For example, individuals with certain autoimmune diseases, such as lupus or rheumatoid arthritis, may produce antibodies that can trigger a false-positive result.
• Previous Infection or Treatment: Individuals who have been previously infected with syphilis and have been successfully treated may continue to have detectable antibodies for an extended period. These residual antibodies can cause false-positive test results.
• Recent Vaccination: Some vaccinations, such as the flu vaccine, may lead to the temporary production of antibodies that can cross-react with syphilis tests, resulting in false positives.
• Lab Error or Contamination: In rare cases, errors in the testing process or contamination of samples can lead to false-positive results.
• Pregnancy: Pregnancy can cause changes in the immune system, leading to false-positive syphilis test results in some cases.
• Testing in Low-Risk Populations: When syphilis prevalence is low in a particular population, the likelihood of false-positive results may increase, as the positive predictive value of the test decreases in low-prevalence settings.

To confirm a positive syphilis test result and distinguish it from a false-positive, additional testing and follow-up may be required. Healthcare providers may suggest a second screening test for the best possible answer to be found about your diagnosis. If either of the tests come out as positive, the chances of infection are incredibly high. 

The United States government and the Centers for Disease Control and Prevention (CDC) require syphilis cases to be reported for several critical reasons. First and foremost, reporting syphilis cases is essential for public health surveillance. By monitoring and tracking the number of syphilis cases, their distribution, and trends over time, health authorities can assess the prevalence of the infection and identify potential outbreaks. Early detection through reporting allows for timely intervention and treatment, preventing disease progression, reducing complications, and limiting transmission to others. Additionally, the data collected from reported cases help public health officials understand the patterns and risk factors associated with syphilis transmission, leading to targeted prevention and control efforts. Reporting also facilitates partner notification and treatment, breaking the chain of infection and reducing community-wide spread. Moreover, it aligns with national and international reporting obligations, contributing to global efforts to combat sexually transmitted infections and improve overall public health. Ultimately, reporting syphilis cases is a fundamental public health measure that enables a rapid response to outbreaks, protects the health of communities, and empowers the implementation of effective preventive measures.

Several medical conditions can be mistaken for syphilis due to overlapping symptoms or similar manifestations. Here are some of the most common conditions we see patients confusing syphilis for: 

• Genital Herpes: Genital herpes is a viral infection caused by the herpes simplex virus (HSV). It can lead to the development of painful sores or blisters on or around the genitals, which may resemble the primary syphilis chancre. However, there are some key differences between the two. Genital herpes sores are usually painful, and they may be filled with clear or cloudy fluid. Additionally, genital herpes tends to recur, with individuals experiencing periodic outbreaks of sores. Differentiating between genital herpes and syphilis is crucial for providing appropriate treatment and management, as they are caused by different pathogens and require distinct approaches for care.
• Genital Warts: Genital warts are caused by certain strains of the human papillomavirus (HPV). They appear as small, flesh-colored bumps or clusters around the genital area. These warts can be mistaken for syphilis sores, especially during the primary stage. However, unlike syphilis chancres, genital warts are usually painless and have a distinct cauliflower-like appearance. HPV is a prevalent sexually transmitted infection, and while it is not curable, its symptoms can be managed through various treatments.
• Contact Dermatitis: Contact dermatitis is a skin condition caused by exposure to irritants or allergens. It can lead to red, itchy, and inflamed skin, which might be mistaken for syphilis rashes or sores. However, contact dermatitis does not involve the presence of syphilis bacteria or viral agents and is not sexually transmitted. Identifying the underlying cause of the skin reaction is crucial for providing the appropriate treatment and avoiding further exposure to the irritant or allergen.
• Eczema: Eczema, also known as atopic dermatitis, is a chronic skin condition characterized by dry, itchy, and inflamed skin. In some cases, eczema patches or lesions may be mistaken for syphilis rashes, especially during the secondary stage when the skin manifestations of syphilis can resemble eczema. However, the presence of other symptoms, such as a history of sexual exposure or the presence of syphilis sores, can help differentiate between the two conditions.
• Psoriasis: Psoriasis is a chronic autoimmune skin disorder that can cause red, scaly patches on the skin. These patches may resemble syphilis rashes, especially when they occur in certain areas of the body. However, psoriasis is not a sexually transmitted infection and has a different underlying cause. A thorough examination and medical history review can help differentiate between psoriasis and syphilis.

Syphilis treatment can include penicillin or doxycycline, which will treat it at each of the four stages. However, The fourth stage will require more specialized treatment due to how advanced it becomes. While the treatment in the fourth stage will not repair the damage wrought by the infection, it will eliminate syphilis entirely in normal cases and provide a negative result months thereafter. 

Someone who has just completed syphilis treatment should refrain from having sex for a specific period to ensure that the infection has been fully cured and to prevent transmission to sexual partners The appropriate period of abstinence from sexual activity after syphilis treatment can vary depending on the stage of the infection and the specific treatment regimen used. Generally, it is recommended to wait for at least 7 to 10 days after the completion of syphilis treatment before resuming sexual activity.

Yes, when syphilis is diagnosed and treated during the early stages (primary and secondary), a single dose of penicillin is typically sufficient to cure the infection completely. Even in cases of latent syphilis, where the infection is "hidden" in the body, penicillin treatment can wipe out the bacterium and prevent the infection from progressing to more advanced stages.

Treatment will remove the syphilis-causing bacteria from the body in the fourth stage, however, the infection may cause irreversible damage to various organs and systems in the body at that point. While treatment can help control the infection and prevent further progression, it may not be able to completely reverse the effects of the infection on organs or tissues that have already been affected.

No, in some cases, this partial control of the infection can result in a period of latency where the individual does not experience noticeable symptoms or may have mild manifestations that go unnoticed. However, it is important to recognize that syphilis remains present in the body during the latent stage, and the infection can become active again, leading to the development of more severe symptoms and potential complications. While the immune response may offer some level of protection, it is not reliable in fully eradicating the bacterium, and without appropriate antibiotic treatment, the infection can persist and potentially lead to serious health consequences. 

When it comes to syphilis treatment and the steps you can take during the process, most doctors will recommend the following: 

• Complete the Full Course of Treatment: Take the prescribed antibiotics, usually penicillin or an appropriate alternative if you are allergic to penicillin, as directed by your healthcare provider. It is essential to complete the full course of treatment, even if you start feeling better before finishing the medication. Completing the treatment is crucial to ensure the complete eradication of the bacterium and prevent the infection from re-emerging.
• Abstain from Sexual Activity: During the period of treatment and as recommended by your healthcare provider, abstain from sexual activity to avoid transmitting the infection to sexual partners. Engaging in sexual activity too soon after treatment could still expose others to the bacterium and lead to reinfection.
• Notify Your Sexual Partners: Inform your current and recent sexual partners about your syphilis diagnosis, even if they may not have visible symptoms. Encourage them to get tested and, if necessary, seek treatment to prevent further transmission of the infection.
• Follow-Up Testing: Follow up with your healthcare provider for recommended testing and check-ups to ensure that the treatment has been successful in clearing the infection from your body. Regular follow-up testing can help monitor your progress and detect any potential recurrence.

Just as well, during the syphilis treatment process, it is equally important that you get plenty of exercise and sleep, eat well-balanced meals, and avoid or reduce stress. When individuals do not make an active effort to live a healthier lifestyle, the body can be vulnerable to reinfection or reduce the capability of the antibiotics included with the treatment. To make the most of the process, your body should be at its best. 

1. Use Condoms Consistently and Correctly: Proper and consistent use of latex or polyurethane condoms during sexual activity can significantly reduce the risk of syphilis transmission and other STIs. Condoms act as a barrier and help prevent contact with syphilis sores or rashes.
2. Limit Sexual Partners: Reducing the number of sexual partners can lower the risk of exposure to syphilis. Engaging in sexual activity with a mutually monogamous partner who is not infected with syphilis further decreases the chances of transmission.
3. Communicate with Partners: Open and honest communication with sexual partners about sexual health is essential. Discussing STI testing, history, and safe sex practices can help make informed decisions together.
4. Get Regular STI Testing: If sexually active, undergo regular STI testing, including syphilis testing, as recommended by healthcare providers. Early detection allows for timely treatment and prevention of further transmission.
5. Avoid High-Risk Sexual Behaviors: Avoid engaging in high-risk sexual behaviors, such as unprotected sex, having sex under the influence of alcohol or drugs, or engaging in sexual activity with individuals of unknown or high-risk infection status.
6. Practice Safe Sex: Engage in safe sex practices to reduce the risk of transmission. Avoid sharing sex toys, which can also transmit infections.
7. Stay Informed: Educate yourself about syphilis, other STIs, and safe sex practices. Being informed empowers you to make responsible decisions about sexual health.

Staying on top of your sexual health requires regular testing and seeking treatment if you think you have been exposed to an STD. At CallonDoc, we offer both testing and treatment options for sexually transmitted infections, all available online for your privacy and convenience. If you or a partner need sexual healthcare visit us today to start a visit.

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