Syphilis tests detect antibodies to the bacterium that causes syphilis (Treponema pallidum) in blood, body fluid, or tissue. The tests are used to screen for or to confirm a syphilis infection. Syphilis is a sexually transmitted disease (STD) that is usually spread during sexual contact, including kissing or oral sex. Tests used to screen for syphilis include: Venereal disease research laboratory (VDRL) test. The VDRL test checks for an antibody that can be produced in people who have syphilis. This antibody is not produced as a reaction to the syphilis bacteria specifically, so this test is sometimes not accurate. The VDRL test may be done on a sample of blood or spinal fluid. The VDRL test is not very useful for detecting syphilis in very early or advanced stages. Rapid plasma reagin (RPR) test. The RPR test also detects syphilis antibodies. Enzyme immunoassay (EIA) test. This is a newer blood test that check for antibodies to the bacteria that cause syphilis. A positive EIA test should be confirmed with either the VDRL or RPR tests.
A syphilis infection can spread through the bloodstream to all parts of the body. If not treated, syphilis can cause severe heart disease, brain damage, spinal cord damage, blindness, and death.
Venereal disease research laboratory (VDRL) and rapid plasma reagin (RPR) tests Normal: The antibody to the syphilis bacteria (reagin) is not present. This is called a nonreactive or negative result.
The antibody reagin is present. This is called a reactive or Abnormal: positive test.