The Treponemal Test is a blood test used to diagnose syphilis, a sexually transmitted infection caused by the bacterium Treponema pallidum. This test detects antibodies that the body produces in response to the infection. It is often used after a non-treponemal test, which screens for syphilis, to confirm the diagnosis. Treponemal tests are highly specific and can remain positive even after successful treatment of syphilis. Common types of treponemal tests include the FTA-ABS (Fluorescent Treponemal Antibody Absorption) and the TP-PA (Treponema Pallidum Particle Agglutination) tests. These tests help healthcare providers determine the presence of syphilis and guide appropriate treatment.