A pruritic, scaly rash appeared on this 42-year-old man's elbows, knees, lower back, and buttocks. Can you ID?
A 42-year-old man presents with a pruritic rash characterized by pink, scaly plaques with a few crusted erosions on the elbows (Figure) knees, lower back, and buttocks. Review of systems was negative, although there was a strong positive family history of celiac disease. He took no medications and was otherwise healthy.
Which of the following do you suspect?