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Updated: Feb 1, 2026

Author Spotlight: Advancing Syphilis Research — Innovations in Treponema pallidum Cultivation and Genetic Engineering
Published on: January 24, 2025
Treponema Pallidum Epidermotropism in Nodular Secondary Syphilis
Jorge Magdaleno-Tapial1, Cristian Valenzuela-Oñate1, José María Ortiz-Salvador1
1Department of Dermatology, Consorcio Hospital General Universitario de Valencia, Valencia, Spain.
Abstract:
Nodular secondary syphilis results from the hematogenous and lymphatic dissemination of spirochetes. Clinically, the lesions appear as partially infiltrated plaques or red-violaceous nodules, which can be solitary or multiple. Several hypotheses have been put forward to explain the formation of these infiltrated or granulomatous lesions. Among the most accepted are the specific hypersensitivity reactions to Treponema pallidum or the lenghty duration of the disease. We present a case of nodular syphilis where immunohistochemistry revealed the presence of multiple spirochetes invading the epidermis.
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