Nonpruritic erythematous plaques.

A 43-year-old man visiting Texas from Hawaii sought care at our dermatology clinic for nonpruritic erythematous plaques on his chest, back, and extremities. The patient reported occasional numbness in his fingers and feet, but denied constitutional symptoms. The patient, who'd had these symptoms for a year, had been previously diagnosed with chronic urticaria and treated with oral antihistamines. He reported that the lesions were never particularly pruritic and he had not responded to previous treatments. An avid outdoorsman, our patient was born and raised in Texas and had been living in Hawaii. His past medical history was significant for severe hand eczema and when asked about medications he was taking, he listed cetirizine, doxepin, and hydroxyzine. On physical examination the patient had multiple pink to red, nonscaly to minimally scaly flat plaques on his forehead, chest, proximal upper extremities, lower back, and distal lower extremities. A 4-mm punch biopsy was taken from a lesion on his lower back and sent for histologic evaluation. The patient's erythrocyte sedimentation rate, rapid plasma reagin, and complete blood count were all within normal limits. What is your diagnosis? How would you treat this patient?