Treponema pallidum - Syphilis
Treponema pallidum subspecies pallidum is the causative agent of venereal syphilis, a sexually transmitted infection (STI). If left untreated, syphilis can result in multisystem involvement with significant morbidity. Traditional serologic screening for syphilis initially uses nontreponemal testing, with confirmation of reactive results using a treponemal test. New reverse algorithms initially use treponemal testing (usually enzyme immunoassays [EIAs] or chemiluminescence immunoassays [CIAs]), with confirmation of reactive results using a nontreponemal test. Of note, mothers infected with syphilis can pass the infection to their children in utero (congenital syphilis). The CDC reported a 153.3% increase in the rate of congenital syphilis in the years 2013 to 2017 (CDC, 2018) and recommends (along with the American Academy of Pediatrics [AAP] and American College of Obstetricians and Gynecologists [ACOG]) that all women be screened for syphilis at the first prenatal visit; women at high risk should have repeat screening at the start of the third trimester and again at delivery (CDC, 2015; U.S. Preventive Services Task Force [USPSTF], 2018).
Last Update: October 2018