Derm Dx: Erythematous Rash on the Upper Back

A 32-year-old man is referred for evaluation of an erythematous rash on his upper back that has been present for approximately 2 months. At age 25, he was diagnosed with systemic lupus erythematosus (SLE), a disease that also affects his mother. Treatment with hydroxychloroquine 200 mg/d was restarted approximately 1 month ago. Examination reveals annular, indurated erythematous plaques, as well ...