Evaluation of the Elecsys Syphilis Immunoassay for Detection of Syphilis in Populations at Risk of Disease in the US and Argentina.

Background: The Elecsys® syphilis immunoassay is an automated, qualitative immunoassay that uses a double-antigen sandwich format to detect antibodies to Treponema pallidum in human serum and plasma. We aimed to validate performance of the immunoassay in various populations at risk for syphilis infection in the US and Argentina.

Methods: Samples were obtained for a number of study cohorts, including participants from routine syphilis testing at high or low risk for syphilis, HIV-positive patients, pregnant women, and patients in various stages of syphilis infection.