Secondary syphilis primarily presenting with multiple nodules on the scalp: Case report and published work review.

Syphilis, a sexually transmitted disease caused by Treponema pallidum, manifests with a broad spectrum of clinical presentations that usually involves skin. Nodular secondary syphilis occurs rarely, and mostly manifests as disseminated papulonodules or plaques over the trunk and limbs. We report an extremely rare case of nodular secondary syphilis that primarily presented with multiple nodules on the scalp, resembling Rosai-Dorfman disease or cutaneous malignant metastasis. Immunohistochemistry confirmed T. pallidum spirochetes microscopically.