Malignant syphilis in an HIV-infected patient

We report a case of malignant syphilis in a 32-year-old HIV-infected man who presented with a number of crusted papulonodular skin lesions scattered on his entire body, accompanied by fever and lymphadenitis. The serological test for syphilis, Treponema pallidum latex immunoassay, showed a positive result. A biopsy specimen from the right upper arm was histopathologically compatible with secondary syphilis and immunohistochemically positive for T. pallidum. Based on these serologic, histopathologic and immunohistochemical findings, a definitive diagnosis of malignant syphilis was made, which was successfully treated with oral antibiotics. Malignant syphilis should be considered when ulceronodular skin lesions are encountered in HIV-infected individuals.