What are the signs and symptoms of syphilis?

Syphilis infection, when untreated, progresses through different clinical stages with characteristic signs and symptoms. After the first infection, symptoms typically develop at around 21 days after the infection, but they may appear anywhere from 10 to 90 days following infection.

Primary syphilis

The first, or primary, stage of syphilis is characterized by the formation of a painless ulcer known as a chancre. This sore develops at the site of infection and is usually solitary. A chancre is usually firm and round in shape. Sometimes, multiple chancres may be present. The chancre contains the infectious bacteria and while the sore is present, the condition is highly contagious. Any contact with the chancre can spread the infection. If the chancre is located in the mouth, for example, even kissing can spread the disease. The chancre lasts for about 3 to 6 weeks and typically then goes away on its own. The use of condoms may also not prevent spread of the illness if the chancre is located on an area of the body not covered by the condom.

Secondary syphilis

If primary syphilis is left untreated, secondary syphilis may develop. This stage of the illness usually occurs weeks to months after the primary stage. Secondary syphilis is characterized by a skin rash that typically does not itch and may easily be mistaken for rashes caused by other illnesses. It may appear on almost any part of the body, including sores inside the mouth, vagina, or anus. The rash of secondary syphilis is often found on the palms of the hands and the soles of the feet, which is unusual for most rashes. In some people, the rash may be mild and not noticed. Raised gray or whitish patches of skin, known as condyloma lata, may also develop, particularly in warm and moist areas of the body such as the armpits, mouth, or groin.

In secondary syphilis, the infection has spread throughout the body, so other symptoms may be associated with the skin manifestations. Fever, enlarged lymph nodes, fatigue, weight loss, hair loss, headaches, and muscle aches have all been reported in the secondary stage of syphilis. These symptoms will eventually subside, but if this secondary stage of the infection is not treated, the infection can progress to tertiary syphilis.

Tertiary syphilis

After the symptoms of secondary syphilis go away, the infection remains latent in the body if untreated. About 15% of infected and untreated people will go on to develop the third stage of syphilis, which can occur as much as 10 to 20 years after the initial infection. Tertiary syphilis is characterized by damage to any number of organ systems and can even be fatal. Tertiary syphilis can cause damage to the brain, nerves, eyes, heart, blood vessels, liver, bones, and joints. Symptoms that can result from the late stage of syphilis include problems with movement, gradual loss of sight, dementia, paralysis, and numbness. Neurosyphilis is the term used to refer to the involvement of the central nervous system and alterations in neurologic function.

Neonatal or congenital syphilis

Untreated syphilis in a pregnant women results in death of the fetus in up to 40% of infected pregnant women (stillbirth or death shortly after birth), so all pregnant women should be tested for syphilis at their first prenatal visit. The screening test is usually repeated in the third trimester of pregnancy as well. If infected babies are born and survive, they are at risk for serious problems including seizures and developmental delays. Fortunately, syphilis in pregnancy is treatable.