Asymptomatic Purpuric Eruption on the Scalp of a Middle-aged Man

Abstract

A man in his 60s presented to the clinic with a several-day history of nontender, nonitchy purpuric rash on his scalp. The patient denied using any over-the-counter or prescription topicals at the affected sites before the onset of the eruption except for petroleum jelly. His medical history was significant for chronic lymphocytic leukemia (CLL) and allergic contact dermatitis. The patient reported being started on ibrutinib and allopurinol therapy 6 weeks prior to the rash onset for treatment of CLL. Physical examination revealed multiple purpuric, nonblanchable macules and patches on the frontal, vertex, temporal, and parietal scalp (Figure , A). A punch biopsy specimen from the scalp was obtained for histopathologic analysis (Figure , B).