Derm Dx: Can You Diagnose This Patient's Rash?

A 46-year-old Hispanic man presents for evaluation of a rash on his back and chest; he first noted the rash 2 days ago after he returned from the Dominican Republic where he spent ample time outdoors. The red areas are tender to light palpation. He is most concerned about white "spots" that are visible in the area. He is currently ...