A 42-year-old man with nodular skin lesions.

Nodular skin lesions are infrequently reported among patients with syphilis. We describe a 42-year-old man with secondary syphilis who presented with a nodular cutaneous eruption involving his neck, upper chest, back, arms, and legs. Because there was uncertainty regarding the diagnosis at presentation, the patient underwent a punch biopsy of one of the lesions. Spirochetes were not seen with a Steiner silver stain, but they were visualized on subsequent immunohistochemical staining. The diagnosis was confirmed with serology, and the patient responded well to treatment with benzathine penicillin G. Given the current increase in syphilis cases across North America, it is critical that clinicians become familiar with some of the less common dermatologic manifestations of this infection so that the diagnosis is entertained and appropriate serologic testing is ordered in a timely fashion.