A 33-year-old man presented with a 2-year history of a florid,
nonitchy rash. It had started on the lower extremities and progressed slowly to involve the trunk and upper limbs. He had no history of relevant illnesses apart from a family history of psoriasis.
Physical examination showed widespread and symmetrically distributed dark purple-red keratotic papules on the lower part of the abdomen and back, inner aspect of the forearms, dorsal surfaces of the hands,
and predominantly on the thighs. On the medial aspect of the thighs,
the lesions were densely concentrated, coalescing into linear, striated,
and reticular patterns (Figure 1). He showed no facial, mucosal, scalp, or nail involvement, and the palms of the hands and soles of the feet were spared.