Syphilis

What is syphilis?

Syphilis is a sexually transmitted infection (STI) caused by the bacterium Treponema pallidum. It can affect various organs in the body, but it is completely curable if detected and treated early.

Symptoms

Syphilis can present in different ways, each with distinct characteristics. It’s important to remember that symptoms vary from person to person, and some individuals may even not show any signs at all:

• primary stage: Sores may appear at the site where the bacteria are present. These can occur on the genitals, anus, mouth, or other areas. These sores, called “chancres,” may heal on their own, but the infection remains and continues to spread
• secondary stage: About two to twelve weeks after the chancre appears, secondary symptoms may develop. These include a non-itchy skin rash (changes in skin color and texture without itching), mucous membrane lesions (such as in the mouth and genitals), fever, malaise, sore throat, hair loss, and swollen lymph nodes (an important part of the immune system that helps fight infections)
• latent stage: After the secondary stage, syphilis can enter a latent stage, where symptoms disappear but the bacteria remain in the body. This stage can last for years, and the person can still transmit the disease even without symptoms
• tertiary stage: If left untreated, syphilis can progress to the tertiary stage, which may cause serious damage to internal organs, including the heart, brain, nerves, eyes, bones, and joints. Complications at this stage can be severe but are generally treatable with proper medical care

Causes

Syphilis is caused by the bacterium Treponema pallidum, which is primarily transmitted through direct contact with lesions of an infected person. The main modes of transmission include:

• sexual contact: Syphilis is primarily a sexually transmitted infection (STI). Transmission occurs through direct contact with a sore or lesion caused by the bacterium during sexual activity, including vaginal, anal, and/or oral sex
• vertical transmission: A person infected with syphilis can pass the infection to the fetus during pregnancy. This is known as congenital syphilis and can lead to serious complications for the baby, including birth defects and damage to the nervous system
• contact with infected blood: Although less common, syphilis can also be transmitted through direct contact with the blood of an infected person. This can happen, for example, through sharing needles or other contaminated instruments

Diagnosis

Treponemal and non-treponemal tests are types of tests used to detect syphilis, a sexually transmitted infection caused by the bacterium Treponema pallidum. Both types of tests use different detection mechanisms and provide different information about the infection.

Non-Treponemal Tests

• VDRL (Venereal Disease Research Laboratory): detects the presence of non-specific antibodies that the body produces in response to infection by Treponema pallidum
• RPR (Rapid Plasma Reagin): similar to the VDRL, this test also detects so-called “non-treponemal antibodies” in the patient’s bloodstream

Treponemal Tests

• FTA-ABS (Fluorescent Treponemal Antibody Absorption): this test detects specific antibodies against Treponema pallidum. It is highly sensitive and specific for syphilis but may remain positive even after the disease is cured, making it most useful for diagnosing active infections
• ELISA test for syphilis: a test used to detect specific antibodies against the disease in the patient’s bloodstream

Treatment

Syphilis is treated with benzathine penicillin, an antibiotic available through Brazil’s public healthcare system (SUS – Sistema Único de Saúde). The dosage depends on the stage of the disease. Penicillin is the most common treatment for syphilis, but it is important to follow the doctor’s instructions.

After completing treatment, it is important to undergo follow-up testing to ensure the infection has been cured. It is also necessary for all sexual partners from the past three months to be tested and, if needed, treated. This helps stop the spread of the disease.

When syphilis is detected during pregnancy, treatment should begin as soon as possible with benzathine penicillin. This is the only medication capable of preventing vertical transmission (from mother to baby). The sexual partner should also be tested and treated to avoid reinfection of the pregnant person. The criteria for appropriate treatment during pregnancy include:

• administration of benzathine penicillin
• starting treatment at least 30 days before delivery
• using the correct medication, dosage, and treatment duration according to the clinical stage of syphilis
• adhering to the recommended interval between doses

Prevention

Syphilis prevention involves practices that reduce the risk of contracting or transmitting the infection. Here are some preventive measures:

• use of condoms: During sexual activity—including vaginal, anal, and oral sex—condoms can significantly reduce the risk of transmitting syphilis and other sexually transmitted infections. It’s important to remember that the disease can also be transmitted through oral sex
• regular testing and medical check-ups: Especially important for individuals with multiple sexual partners or those in higher-risk groups. Early detection allows for proper treatment and helps prevent complications
• proper treatment of partners: If someone is diagnosed with syphilis, it is crucial that all sexual partners are informed so they can be tested and treated if necessary. This helps break the chain of transmission

References

Syphilis — Ministry of Health

SESA – Acquired Syphilis and Congenital Syphilis

By Einstein Editorial Board