Biopsies are occasionally necessary to confirm the diagnosis of secondary-stage syphilis, currently achieved by clinico-serological correlation. However, histopathologic examination may offer clues that can lead to the diagnosis of the disease in previously unsuspected or unusual cases. We report the case of a 35-year-old male patient with vitiligo-like lesions for two years, whose diagnosis of syphilis was suggested only after histopathologic examination. Some microscopic aspects observed are discussed and compared to data from the literature.