Syphilis testing is used to diagnose syphilis, a sexually transmitted infection caused by the bacterium Treponema pallidum.
Common blood tests:
Nontreponemal tests: VDRL (Venereal Disease Research Laboratory) and RPR (Rapid Plasma Reagin)
Treponemal tests: FTA-ABS (Fluorescent Treponemal Antibody Absorption) and TPPA (Treponema pallidum Particle Agglutination)
Initial screening with a nontreponemal test.
If positive, confirmed with a treponemal test.
Syphilis tests can help diagnose the infection in the early stages, when it’s easiest to cure.
Finding and treating the infection early can also prevent the spread of syphilis to others.
Syphilis testing usually involves two steps.
In most cases, the first step is a screening test to check for antibodies that are linked to having a syphilis infection.
Other things may trigger the immune system to make these antibodies, such as autoimmune diseases, other infections, and vaccinations.
Rapid plasma reagin (RPR), is a blood test.
Venereal Disease Research Laboratory (VDRL) test, which can be done on blood or spinal fluid
If the antibodies linked to syphilis infections are present, a second test to confirm whether syphilis is present.
The second test looks for antibodies that the immune system makes only to fight off syphilis.
Treponema pallidum particle agglutination assay (TP-PA)
Fluorescent treponemal antibody absorption (FTA-ABS) test
Microhemagglutination assay for antibodies to T. pallidum (MHA-TP)
T. pallidum hemagglutination assay (TPHA)
T. pallidum enzyme immunoassay (TP-EIA)
Chemiluminescence immunoassays (CLIA)
The Centers for Disease Control and Prevention recommends that all pregnant people have a syphilis test at their first prenatal visit.
Pregnant people who are more likely to become infected with syphilis should be tested again at 28 weeks of pregnancy and at delivery.