A 42-year-old man presents to the ED complaining of a rash on his chest and back. He says it's been there for some time, but it waxes and wanes in severity. It does not hurt, and is only mildly itchy. He denies any other complaints.
He has made no changes to his diet nor switched detergents, soaps, or shampoos. He takes no medications, and has no allergies. His physical exam is unremarkable except for this erythematous rash present on his trunk.
There is minimal induration and scaling associated with it. The largest of the lesions is pictured here. He has no lymphadenopathy.
What is your diagnosis? Are there any other pertinent historical questions or physical exam findings that may help in the diagnosis? See p. 10.