REPORT OF A CASE
A 68-year-old man presented with an 8-month history of a pruritic zosteriform eruption of the left trunk and thigh areas, corresponding roughly to the T-11 and L-4 dermatomes. He was otherwise healthy with the exception of hypertension. Medications included hydrochlorothiazide, metoprolol, and captopril, none of which was temporally related to the onset of the eruption. No prior trauma or dermatologic history was obtained.Physical examination revealed a collection of scaling polygonal papules limited to a serpiginous or zosteriform pattern (Figs 1 and 2). Mucous membranes were normal and the nails revealed longitudinal ridging and pitting. A punch biopsy was performed; representative sections are shown in Figs 3 and 4.What is your diagnosis?
Zosteriform lichen planus.
The biopsy specimen demonstrated a prominent granular layer with a lichenoid lymphocytic infiltrate obscuring the dermoepidermal junction. Prominent vacuolar change, Civatte body formation, and pigment