Syphilis infections (Treponema pallidum) continue to be reported at a high rate, both nationally as well as in Spokane County. Unless a person is symptomatic with primary lesions present on exam, syphilis must be confirmed through serologic testing. Unfortunately, there is no singular diagnostic test available for syphilis. Instead, we rely on multiple serologic tests in combination to confirm a syphilis diagnosis. Historically, two testing algorithms have been used (see table below). SRHD recommends the reverse algorithm for screening and initial diagnosis of syphilis. This means the treponemal test (EIA, TPPA, or FTA) will be run initially, and if reactive, it will reflex to the non-treponemal RPR (rapid plasma reagin) with titer. If two of the three tests are reactive, it is likely a case of syphilis and a clinician should consider treatment. If a patient has a history of syphilis, an RPR titer is all that is needed because the treponemal tests will likely remain reactive for life.