Syphilis is a sexually transmitted infection caused by the bacterium Treponema pallidum. It is a systemic disease that has a highly variable course. Syphilis goes through active stages with symptoms and latent stages with no symptoms. Without treatment, syphilis can cause severe complications and even death. Thankfully, syphilis is easy to cure, especially in its early stages. Antibiotics like penicillin are highly effective at killing the syphilis bacteria and preventing further damage.
What is syphilis?
Syphilis is a complex systemic sexually transmitted disease (STD) caused by the bacterium Treponema pallidum. It can infect both men and women and is usually spread through vaginal, oral, or anal sex with an infected partner. An infected mother can also pass syphilis to her unborn baby during pregnancy.
Syphilis progresses through several stages if left untreated:
Primary syphilis
The first sign of infection is a single painless sore called a chancre. This sore appears around 3 weeks after infection where the bacteria first entered the body. Commonly it is found on the penis, vulva, vagina, rectum, lips, or mouth. The chancre heals on its own in 3-6 weeks.
Secondary syphilis
Weeks after the chancre heals, a rash and other symptoms may appear. A rash of rough, red or reddish brown spots often shows up on the palms of the hands and bottom of the feet. Rashes can also appear on other parts of the body. Other symptoms at this stage may include fever, swollen lymph nodes, sore throat, patchy hair loss, headaches, weight loss, muscle aches, and fatigue. Even without treatment, these symptoms go away in a few weeks or months.
Latent syphilis
After the symptoms of secondary syphilis resolve, syphilis enters a latent stage. At this point there are no symptoms, but the infection still remains in the body. Latent syphilis is categorized into early latent and late latent stages. Early latent syphilis occurs within the first year of infection. Late latent syphilis occurs thereafter and can last for years.
Tertiary syphilis
This is the most severe and dangerous stage of untreated syphilis. About one-third of people who do not get treated will progress to tertiary syphilis. It can occur 10-30 years after the initial infection. At this point, the disease can damage the heart, brain, and other organs, leading to organ failure and death.
Syphilis does real damage when left untreated. Thankfully, it’s easy to test for and treat syphilis, especially in its early stages.
How do you test for syphilis?
There are two main types of tests that can diagnose syphilis:
Blood tests
Blood tests are the most common way to screen and confirm syphilis. A simple blood draw can be analyzed in a lab. Two examples of blood tests include:
– Nontreponemal tests: This is usually the first screening test for syphilis. The most common is the VDRL (venereal disease research laboratory) test or RPR (rapid plasma reagin) test. These look for antibodies produced by the body in response to syphilis infection. However, they sometimes give false positive results, so positive results are confirmed with a treponemal test.
– Treponemal tests: These tests look specifically for antibodies against the bacterium that causes syphilis. The FTA-ABS (fluorescent treponemal antibody absorption) test or TPPA (T. pallidum particle agglutination) test can confirm the results of an initial nontreponemal test.
If a blood test is positive, further testing can determine the stage of syphilis.
Microscopy
During the primary or secondary stages of syphilis with an active sore or chancre, a sample of fluid from the sore can be examined under a microscope. This allows direct visualization of the syphilis bacterium.
Cerebrospinal fluid test
For suspected neurosyphilis, when the infection has spread to the nervous system, a sample of cerebrospinal fluid (CSF) may be tested. CSF tests look for signs of infection and inflammation.
With prompt diagnosis and treatment, further progression of the disease can be stopped.
How do antibiotics cure syphilis?
Syphilis is easy to cure, especially in its early stages. Penicillin, an antibiotic, is the preferred treatment for all stages of syphilis. Penicillin is highly effective at killing the Treponema pallidum bacteria that cause syphilis.
Here’s how penicillin works to cure syphilis:
1. Penetrates bacteria cell walls
Penicillin is able to penetrate the cell wall of the bacteria cells. The cell wall protects the inner workings of bacterial cells.
2. Inhibits cell wall synthesis
Penicillin inhibits the formation of peptidoglycan cross-links. This is an essential component of the bacterial cell wall. When their cell wall synthesis is disrupted, bacteria cells are unable to grow and divide properly.
3. Leads to cell lysis and death
The weakened cell walls eventually burst due to osmotic pressure from within the cells. This leads to lysis and death of the bacterial cells.
After penicillin treatment, follow up blood tests are done to confirm the infection is gone. It may take 3-6 months for antibodies to clear from the bloodstream after treatment.
One shot of penicillin can cure syphilis during the primary, secondary, or early latent stages. Late latent syphilis requires three doses given at weekly intervals. Tertiary syphilis requires prolonged therapy with high doses of intravenous penicillin.
What happens if syphilis isn’t treated?
Without treatment, syphilis can progress through its stages over many years and eventually lead to serious complications:
– Skin and tissue destruction
Untreated syphilis can cause inflamed nodules or gummas in the skin, bones, and other tissues. This leads to damage of the affected area.
– Neurosyphilis
Up to 40% of people with untreated syphilis will develop neurosyphilis as the infection spreads to the nervous system, including the brain and spinal cord. This causes headache, difficulty coordinating muscle movements, paralysis, numbness, dementia, and ultimately death.
– Blindness
Syphilis can lead to injuries in the eye, including anterior uveitis, posterior uveitis, chorioretinitis, and optic neuritis. This can cause permanent blindness.
– Deafness
If syphilis spreads to the ears, it can lead to auditory nerve damage and hearing loss, including deafness.
– Cardiovascular disease
Up to 10% of those with untreated late-stage syphilis experience cardiovascular problems including heart disease and aortic aneurysms. This can be fatal.
– Stillbirths
Pregnant women with syphilis have a high risk of stillbirth if the infection is left untreated. Some studies report stillbirth rates as high as 40%.
The good news is that proper screening and prompt antibiotic treatment can prevent complications and additional spread of the disease.
Can syphilis come back after treatment?
In most cases, syphilis does not come back after a person is properly treated, especially if antibiotics were administered in the early stages while the infection is localized.
However, there are rare cases where syphilis recurs after initial antibiotic treatment:
– Reinfection from a new partner: Having sex with an untreated partner can lead to reinfection with syphilis for either person.
– Failure to treat partners: All partners should be treated to prevent ping-pong reinfections back and forth.
– Treatment too late: Treatment in the late latent or tertiary stage can sometimes fail to eliminate all bacteria.
– Inadequate dose or duration: Missing doses or not taking antibiotics for the full recommended course raises the risk of relapse.
To prevent relapse, follow-up blood tests are important to confirm complete eradication of the bacteria after treatment. Avoid sex until cured and notify partners so they can also get tested. Using condoms correctly can reduce the risk of reinfection.
How to prevent syphilis transmission?
Here are some key ways to avoid getting or spreading syphilis:
Know your status and get tested
Getting periodic STI testing is important, especially if you have new partners or engage in unprotected sex. Blood tests and microscopy can accurately diagnose syphilis.
Notify partners
If you test positive for syphilis, alert recent partners so they can also get tested and treated.
Use condoms
Using condoms correctly every time you have sex helps prevent syphilis transmission. However, condoms only cover certain body parts, so sores in other areas can still spread infection.
Limit partners and avoid risky sex
Decreasing partners, avoiding anonymous sex partners, and avoiding concurrent partners can lower STI risk.
Get prompt treatment
Seek treatment at the first sign of symptoms, and take antibiotics according to stage-specific medical guidelines.
Wait until cured
After treatment, wait until blood tests confirm cure before having unprotected sex again.
Ensure partners get treated
Coordinate followup treatment for all partners to prevent ping-pong reinfections back and forth.
Following these precautions and getting regular medical checkups can help prevent the spread of syphilis.
Conclusion
Syphilis is a dangerous sexually transmitted infection, but it is readily curable, especially when treated in its early stages. Single doses of antibiotics like penicillin are highly effective at killing the syphilis bacteria and preventing transmission. However, without treatment, syphilis can progress through debilitating stages and eventually lead to serious organ damage and even death.
Thankfully, syphilis is easy to diagnose through simple blood tests, microscopy, or spinal fluid analysis. Public health efforts should focus on increasing access to medical testing and prompt antibiotic treatment. This includes proper follow up to ensure complete cure, as well as partner notification and treatment.
Safety precautions like condoms, limiting partners, and not having sex while contagious can also reduce syphilis spread on an individual level. With continued vigilance and open communication between partners, syphilis can be contained and its devastating consequences averted.