Syphilitic placentitis: Demonstration ofTreponema pallidum by immunoperoxidase staining

Abstract
We report a case of early congenital syphilis in which the placenta showed diffuse proliferative villitis andTreponema pallidum was identified by indirect immunoperoxidase stain in formalin-fixed paraffin-embedded placental tissue. This is the first report demonstratingT. pallidum in placental tissue using an immunohistochemical method.