A 74-year-old Hispanic man presented with a 3-month history of pruritic, scaly patches, and plaques on the palmar surfaces of his hands (Figure 1) and lateral flanks. He had no history of atopic dermatitis or allergies and no other pertinent medical history. His review of systems revealed a mild increase in diarrhea, insomnia, and paroxysmal bouts of pruritus to affected areas and buttocks. His wife had traveled to Mexico 4 months prior and had developed a nonspecific gastroenteritis on return from the trip.