Hyperpigmented annular patches

Case #1

A 22-year-old man presents with an 8-week history of an asymptomatic rash on his face, torso, and groin. He is otherwise healthy, and a review of symptoms finds he is negative for fever, malaise, joint pains, and headaches. He is a student at the local college and reports having had unprotected sex with several partners over the past year. ...