Abstract Sweet syndrome is an inflammatory disease characterized by fever, neutrophilia, papules and erythematous plaques, and a skin neutrophilic infiltrate. Syphilis has been reported among the infectious causes of Sweet syndrome. Syphilis can present atypical manifestations; a rare presentation is nodular syphilis, characterized by nodules with granulomas and plasma cells at histopathology. This case report presents a 20-year-old woman patient, with plaques and nodules, and systemic symptoms. The histopathological exam revealed both non-tuberculoid granulomas and a dense infiltration of polymorphonuclear neutrophils in the dermis. These findings, plus laboratory abnormalities, characteristic of both conditions, were conclusive for Sweet syndrome and nodular syphilis association.