Teen With Itchy Papular Rash on Face and Arms

This monomorphic papular rash is unrelated to medications, recent sickness, or exposure to poison oak. It developed about 6 days earlier.

This 15-year-old has a pruritic, flat-topped, monomorphic papular rash on his face and arms for the past 6 days. He takes no medications, has not been sick recently, and has not been exposed to poison oak.

Your diagnosis?