Screening for congenital syphilis with TPPA and TRUST in 7800 neonates

Abstract

Objective To assess the value and clinical applicability of non-treponemal antigen serologic test and Treponema pallidum antigen serologic test in the diagnosis of congenital syphilis. Methods Totally,7800 newborns were collected from the out-patient and in-patient department. Toluidine red unheated serum test (TRUST) was conducted to quantitatively detect non-treponemal antibodies and Treponema pallidum particle agglutination assay (TPPA) to qualitatively detect specific treponemal antibodies in these subjects. The results of first serology test for syphilis were assessed for neonates with confirmed congenital syphilis. The sensitivity and specificity in the diagnosis of congenital syphilis were compared between TPPA and TRUST.Results Of the 7800 newborns undergoing syphilis serology testa, 60 were positive for TPPA and TRUST,including 15 cases of congenital syphilis, 47 were positive for TPPA but negative for TRUST, including 5 cases of congenital syphilis. The sensitivity and specificity were 75% (5/20) and 99.41% (7734/7780) respectively for TRUST in the diagnosis of congenital syphilis, 100% (20/20) and 98.88% (7693/7780) respectively for TPPA. Conclusion TPPA seems more applicable than TRUST to the screening for congenital syphilis.