Diffuse Cutaneous Eruption

A man presented with a pruritic cutaneous eruption that began on his scalp and face and over 2 months spread across most of his body. Physical examination revealed confluent salmon-colored plaques with areas of unaffected skin; waxy, exfoliative scale on the volar aspect of the hands and feet; and ectropion. He had no history of psoriasis, atopic dermatitis, or other skin disorder, and no recent viral or bacterial infection. What is the diagnosis and what would you do next?