A man has red scaling skin all over his body, with islands of normal skin. What is this dermatosis?
Over a four-week period, a 48-year-old man developed almost universal red scaling skin (erythroderma) with islands of sparing (Figure 1). The process had started on the face and scalp and progressed over his trunk and arms and subsequently to his legs. His palms (Figure 2) and soles were covered by a thick layer of keratin (keratoderma) with an orange hue. There was no previous history of a similar episode. The patient was not on any medications. The skin biopsies showed a thickened epidermis and a loose laminated stratum corneum with retained nuclei (parakeratosis). The underlying dermis showed a scant infiltrate of lymphocytes lacking atypia (Figure 3).