VDRL (RPR), Serum

Syphilis tests are used to screen for and/or diagnose infection with Treponema pallidum, the bacterium that causes syphilis. For more details about syphilis infection, see the What is being tested?
section. Several different types of tests are available. Antibody tests are most commonly used. Antibody tests (serology)ûthese tests detect antibodies in the blood and sometimes in the cerebrospinal fluid (CSF). Two general types are available for syphilis testing, nontreponemal antibody test and treponemal antibody test (derived from the name of the bacterium). Either type may be used for syphilis screening but must be followed by a second test that uses a different method to confirm a positive result and to diagnose active syphilis: Nontreponemal antibody tests--these tests are called nontreponemal because they detect antibodies that are not specifically directed against the Treponema pallidum bacterium. These antibodies are produced by the body when an individual has syphilis but may also be produced in several other conditions. The tests are highly sensitive but, since they are non-specific, false-positive results can be caused by, for example, IV drug use, pregnancy, Lyme disease, certain types of pneumonia, malaria, tuberculosis, or certain autoimmune disorders including lupus. A positive screening result must be confirmed with a more specific (treponemal) test. Nontreponemal tests include: RPR (Rapid Plasma Reagin)--in addition to screening, this test is useful in monitoring treatment for syphilis. For this purpose, the level (titer) of antibody is measured. It may also be used to confirm the presence of an active infection when an initial test for treponemal antibodies is positive (see below). VDRL (Venereal Disease Research Laboratory)--in addition to blood, this test is primarily performed on CSF to help diagnose neurosyphilis. Treponemal antibody tests--these blood tests detect antibodies that specifically target T. pallidum. They are highly specific for syphilis, meaning other conditions are unlikely to cause a positive result. However, once a person is infected and these antibodies develop, they remain in the blood for life. By comparison, nontreponemal antibodies typically disappear in an adequately treated person after about 3 years. Therefore, a positive treponemal screening result must be followed by a nontreponemal test (such as RPR) to differentiate between an active infection (or reinfection) and one that occurred in the past and was successfully treated. Treponemal antibody tests include: FTA-ABS (Fluorescent treponemal antibody absorption)--this test is useful after the first 3-4 weeks following exposure. In addition to blood testing, it can be used to measure antibodies to T. pallidum in the CSF to help diagnose neurosyphilis. TP-PA (T. pallidum particle agglutination assay)--this test is sometimes performed instead of FTA-ABS because it is more specific and there are fewer false positives. MHA-TP (Microhemagglutination assay)--another confirmatory method; this test is used much less commonly now. Immunoassays (IA)--in more recent years, several automated tests have been developed, making them convenient for screening purposes. Direct detection of bacteriaûthese tests are less commonly performed: Darkfield microscopy--this method may be used in the early stages of syphilis when a suspected syphilis sore (chancre) is present. It involves obtaining a scraping of the sore, placing it on a slide, and examining it with a special instrument called a dark-field microscope. Molecular testing (polymerase chain reaction, PCR)--this test detects genetic material from the bacteria in the sample from the sore, in blood, or in CSF.

How long does it take to get results from a syphilis test?

Samples are typically sent to a laboratory and results could take 3-5 days.

How can syphilis be prevented?

The most reliable ways to avoid infection with syphilis or any sexually transmitted disease are to abstain from oral, vaginal, and anal sex or to be in a long-term, mutually monogamous relationship with an uninfected partner. People who are sexually active should correctly and consistently use condoms to reduce the risk of infection with syphilis and other STDs.

Why is having syphilis a problem during pregnancy?

Syphilis in pregnancy can cause many health problems for the infant, including low birth weight, premature delivery, and even stillbirth. In 2014, the U.S. Centers for Disease Control and Prevention (CDC) received 458 reports of syphilis cases in children who contracted syphilis from their mothers, known as congenital syphilis. Sometimes newborns with syphilis may not have signs of the disease. However, without immediate treatment, the newborn could develop cataracts, deafness, or seizures. According to the American Sexual Health Association, many cases of congenital syphilis go u oticed until symptoms appear in childhood or adolescence.

The CDC and the U.S. Preventive Services Task Force recommend that pregnant women be tested for syphilis, preferably at the first prenatal visit. The CDC also recommends testing during the third trimester for higher risk women.

Where can I get tested?

Visit the CDC webpage Get Tested (link is external) to find out where you can get tested. You can input your zip code and find a local testing site.

Should I tell my partner that I have syphilis?

Yes, you should tell your sexual partner(s) that you have syphilis so they can get tested and treated.

If I get treated, can I get syphilis again?

Yes. Even though treatment will cure your infection, you can get it again if you are exposed again.