Syphilis Tests Test
Syphilis tests check your blood for signs of a syphilis infection. They look for antibodies your immune system makes in response to the bacteria that causes syphilis. Testing usually involves two steps: a screening test and a confirmatory test.
What this test measures
Syphilis tests generally look for certain antibodies in your blood. Antibodies are proteins that your immune system makes when it finds harmful substances in your body. In this case, the harmful substance is the bacterium that causes syphilis.
What your results mean
Reference ranges vary by laboratory and by your age and sex. MedlinePlus does not publish a single normal range for this test — always read your result against the range printed on your own lab report and discuss it with your provider.
Higher-than-normal results
If your screening test results are positive, it means you have antibodies that may be from a syphilis infection. Your provider will likely order a second test to confirm whether or not you have syphilis.
Lower-than-normal results
If your screening test results are negative (normal), it means you probably don't have a syphilis infection. However, it doesn't completely rule out the possibility. Antibodies can take a couple of weeks to develop.
Frequently asked questions
What are the different names for syphilis tests?
Other names include rapid plasma reagin (RPR), Venereal Disease Research Laboratory (VDRL), fluorescent treponemal antibody absorption (FTA-ABS) test, agglutination assay (TP-PA), darkfield microscopy, and several others.
How does syphilis spread?
Syphilis spreads through vaginal, oral, or anal sexual contact with someone who has the infection. It can also pass during pregnancy to the fetus.
What are the stages of syphilis?
Syphilis usually develops in four stages: first stage (painless sore), second stage (fever, swollen glands), third or latent stage (no symptoms but infection persists), and fourth stage (severe symptoms like dementia and blindness).
What does a positive screening test mean?
A positive screening test means you have antibodies that may be from a syphilis infection. Your provider will likely order a second test to confirm whether or not you have syphilis.
How is syphilis treated?
If confirmed, syphilis is usually treated with penicillin, an antibiotic. Antibiotic treatment cures most early-stage infections, but late-stage treatment cannot undo damage already caused.
Related lab tests
Sources
- MedlinePlus: Syphilis Tests — NIH MedlinePlus
Last updated . Information is aggregated from official public sources and is not a substitute for professional medical care.