Syphilis

Also known as: Venereal disease research laboratory; VDRL; Rapid plasma reagin; RPR; Fluorescent treponemal antibody absorption test; FTA-ABS; Treponema pallidum particle agglutination assay; TPPA; Microhemagglutination assay; MHA-TP; Darkfield microscopy

Formal name: Syphilis detection test

Related tests: Hepatitis C; HIV antibody test

The Test Sample

What is being tested?

The test is looking for presence of Treponema pallidum, the that causes syphilis. Syphilis is an infectious disease that is most often spread by sexual contact, such as through direct contact with a syphilis sore (chancre). It is easily treated but can cause severe health problems if left untreated. An infected mother can also pass the disease to her fetus, with serious and potentially fatal consequences for the baby.

According to the US Centers for Disease Control and Prevention (CDC), over 40,000 cases of syphilis were reported in 2007, including 11,466 cases of primary and secondary (P&S) syphilis. Most of the P&S syphilis cases in 2007 occurred in individuals 20 to 29 years of age.

There are several stages with syphilis. The primary stage begins about 2-3 weeks after being infected. One or more sores, called chancres appear, usually on the part of the body exposed to your partner's chancre, such as the penis or vagina. However, the chancre is usually painless and may go unnoticed, especially if it is in the rectum or on the cervix, and disappears within 4-6 weeks.

Secondary syphilis begins 2-8 weeks after the chancre first appears. It is marked by a skin rash that often is rough, red, and spotted, appearing frequently on the palms of the hands and the bottoms of the feet. There may be other symptoms as well, such as fever, fatigue, swollen lymph glands, sore throat, and body aches. If untreated, syphilis may continue into a latent stage, during which an infected person has no symptoms but continues to have the infection, and this stage can last for years. If still untreated, about 15% of people will develop the complications of late, or tertiary, syphilis. In these cases, the bacteria can damage the heart, eyes, brain, nervous system, bones, joints, or almost any other part of the body. This stage can last for years, with the final stage leading to mental illness, blindness, other neurological problems, heart disease, and death.

Syphilis can be treated with antibiotics, preferably penicillin. Newly acquired infections can be cured easily. A longer treatment may be needed to cure someone who has been infected for more than a year.

How is the sample collected for testing?

There are several different screening methods and tests; therefore, different samples are needed.

For new infections, your doctor may take a scraping from a chancre on the affected area, such as the cervix, penis, anus, or throat.
Your doctor may have blood drawn from a vein in your arm for an additional test.
If you have late or latent stages of the disease with suspected brain involvement (neurosyphilis), your doctor will order a spinal tap to check your cerebrospinal fluid (CSF) for infection.

NOTE: If undergoing medical tests makes you or someone you care for anxious, embarrassed, or even difficult to manage, you might consider reading one or more of the following articles: Coping with Test Pain, Discomfort, and Anxiety, Tips on Blood Testing, Tips to Help Children through Their Medical Tests, and Tips to Help the Elderly through Their Medical Tests.

Another article, Follow That Sample, provides a glimpse at the collection and processing of a blood sample and throat culture.

Is any test preparation needed to ensure the quality of the sample?

No test preparation is needed.