Rapid plasma reagin

The rapid plasma reagin (RPR), RPR titer, or RPR test refers to a type of rapid diagnostic test that looks for non-specific antibodies in the blood of the patient that may indicate a syphilis infection. The term reagin means that this test does not look for antibodies against the actual bacterium, Treponema pallidum, but rather for antibodies against substances released by cells when they are damaged by T. pallidum. In addition to screening for syphilis, a titer can be used to track the progress of the disease over time and its response to therapy.