Which screening test is confirmed with the FTA ABS for syphilis?

The rapid plasma reagin (RPR) and Venereal Disease Research Laboratory (VDRL) tests are non-treponemal tests commonly used as initial screening tools for syphilis. These tests are designed to detect antibodies that may indicate the presence of syphilis infection, but they are not specific to Treponema pallidum, the bacterium that causes syphilis. As a result, positive results from these tests necessitate further confirmatory testing to establish a definitive diagnosis.

The FTA ABS (Fluorescent Treponemal Antibody Absorption) test is a treponemal test that specifically detects antibodies directed against the Treponema pallidum. When a non-treponemal test like the RPR or VDRL comes back positive, the FTA ABS is performed to confirm the diagnosis of syphilis. This sequential approach helps to reduce false-positive rates associated with non-treponemal tests and ensures accurate diagnosis.

In summary, the RPR/VDRL serves as an effective initial screening method for syphilis, and subsequent confirmation with the FTA ABS is crucial for verifying the presence of the infection.