Eruptive melanocytic nevi during azathioprine therapy for antisynthetase syndrome.

Eruptive melanocytic nevi (EMN) are rare multiple benign melanocytic nevi that develop within a few months. The phenomenon has been associated with a variety of dermatologic and systemic conditions, including Stevens-Johnson syndrome, toxic epidermal necrolysis, epidermolysis bullosa, Addison disease, human immunodeficiency virus infection, and internal malignancy, among others. It also is commonly attributed to medications, particularly immunosuppressive and chemotherapeutic agents. We report a case of EMN in a 50-year-old man undergoing azathioprine therapy for antisynthetase syndrome.