Syphilis is a sexually transmitted disease caused by a bacterium in the Treponema genus. In addition to transmission through sex, it can also be spread to a fetus or baby during pregnancy or at birth. This disease is relatively easily treated using modern antibiotics. When allowed to progress untreated, however, it goes through four major stages and can lead to severe neurological and cardiovascular symptoms. Basic STD testing can detect syphilis early, along with many other dangerous infections.

Syphilis Stages and Symptoms
Untreated syphilis proceeds through four stages and is often ultimately fatal. Primary syphilis comes from direct contact with another person’s infectious lesions. It causes a chancre to appear at the point of contact anywhere between three and 90 days after exposure. This is usually painless, firm and non-itchy, eventually turning into a painful ulcer. Most people get primary syphilis lesions on the genitals, but they may appear elsewhere on the body, too. The lymph nodes in the immediate area swell up. Without treatment, lesions last for three to six weeks before healing.

Secondary syphilis appears shortly after the lesions of primary syphilis heal, usually four to 10 weeks after a primary infection. This part of the disease can take many different forms. Many people develop reddish-pink rashes on their hands, feet and trunk. Some people get warty lesions on their mucus membranes. Sore throat, weight loss, headache, hair loss and fever are all common. In rare cases, secondary syphilis can cause kidney and liver problems, arthritis, eye trouble and other health issues. These symptoms often go away after three to six weeks, but about a quarter of patients have recurrent secondary symptoms. It is also possible to progress to secondary syphilis without having shown signs of a primary infection.

The third stage of syphilis is latency. Latent syphilis may be either early, at less than one year after secondary infection, or late, at more than one year later. This stage is relatively quiet. The disease stays in the bloodstream but the patient has no obvious symptoms. Latent syphilis can be detected only through testing. Syphilis in a late latent stage is less contagious than the early type.

The last stage of syphilis is tertiary infection. This usually appears after three to 15 years of latency and comes in three main types. About a third of infected people develop tertiary disease, which can be unsightly and dangerous to the patient but is not infectious. The gummatous form of tertiary syphilis can appear up to 45 years after the initial infection but usually occurs earlier. It is characterized by the formation of inflamed tumor-like growths that affect the liver, bones and skin. The neurological form of tertiary syphilis attacks the central nervous system, causing meningitis, poor balance and pain in the extremities. The late stages happen four to 25 years after primary infection. Some people with tertiary syphilis develop the cardiovascular form. This appears 10 to 30 years after the initial exposure and can cause aneurysms.

Syphilis Transmission
This disease can be spread via contact with mucous membranes or damaged skin. People can get syphilis by having oral, anal or vaginal sex. In some rare cases, they can even get it through kissing an infected person. Pregnant people can also spread the disease to their children during pregnancy or childbirth, since the bacteria can move through the blood or pass through the membranes of the birth canal. About 30 to 60 percent of people who are exposed to secondary or primary infections get the disease, but many people have multiple exposures.

Rapid Plasma Reagin Testing
The rapid plasma reagin, or RPR, rest looks for non specific antibodies produced by the immune systems of infected patients in response to the syphilis bacterium. This test can be used not just to diagnose the disease but also to track its progress and response to treatment. This test is very good at detecting infections even when syphilis is present. Some people with other vital infections may suffer false positives with an RPR test, as can some elderly patients. Because of this factor, people who receive a positive result on an RPR syphilis test should have other tests performed to confirm the diagnosis.

Other Blood Tests
Some doctors use a Venereal Disease Research Laboratory test developed in 1906 instead of the more convenient RPR test. Like the RPR, the VDRL test looks for general antibodies instead of syphilis-specific compounds. It can also produce a false positive. More sensitive tests are usually reserved for confirmation of a diagnosis, since both the treponema pallidum particle agglutination assay and the fluorescent treponemal antibody absorption test are more expensive and difficult to perform than general screenings. These tests produce more detailed results; the TPPA has a sensitivity of 85 to 100 percent in primary infections and a 98 to 100 percent sensitivity in secondary and latent stages.