Blaschkoian Lichen Planus in an Amazghi; A Rare Case Report

Abstract

Lichen planus (LP) is a common acquired inflammatory dermatosis of unknown origin with several morphological forms. Linear lichen planus is frequently seen but cases of zonal/ zosteriform/ dermatomal/ blaschkoid LP are rare. Typically LP is merely acknowledged as an old companion to a dermatologist in the clinic. Nonetheless sometimes it comes in masquerades. Many reports have documented LP to occur in scars of previous herpes zoster (HZ) lesions. Zosteriform LP without evidence of HZ is an extremely rare occurrence in the head and neck area. To the best of my knowledge such a condition has not been reported in the literature previously. I report a healthy 53-year old Amazaghi woman with grouped lichenoid, unilateral linear plaque skin lesion on the right side of the face that followed the lines of Blaschko with no previous history of HZ on the involved area. The punch biopsy specimen confirmed the typical histology of lichen planus. A clinical diagnosis was made based on the clinical picture and biopsy reading. Usually Blaschko linear skin lesions develop later in life with distinctive features, and thus it should be differentiated from other acquired skin dermatoses. I report this case of LP type for its scarcity and to add one more case to the list of existing literature, with the idiosyncrasy of late presentation onset.