A 4-year-old girl with a bizarre polycyclic rash on her back and chest.
This 4-year-old child developed a sudden onset, bizarre, red, polycyclic rash predominantly on her back, chest, and arms. The parents report that she complains it is extremely pruritic. They also report that the bizarre geometric patterns seem to move over time; that is, several hours later, they are still present but they have assumed different shapes and are in slightly different location
What's your diagnosis?