Histologic features of chronic cutaneous lupus erythematosus of the scalp using horizontal sectioning: Emphasis on follicular findings.

Abstract

Chronic cutaneous lupus erythematosus (CCLE) often affects the scalp resulting in scarring alopecia. While histopathologic findings of CCLE have been well described, there is little written on the morphologic changes to the hair follicles in this condition. We aim to determine the histopathologic findings of hair follicles in CCLE of the scalp. We conducted a retrospective study of 33 transversely sectioned skin biopsy specimens of CCLE of the scalp at the Skin Pathology Laboratory at Boston University between April 2005 and March 2015. New findings include basaloid follicular epithelium lacking hair follicles at deep levels, follicular miniaturization, increased catagen/telogen hair follicles, and pigment casts. Two histopathologic patterns could be discerned, an alopecia areatalike pattern and a lichen planopilarislike pattern. Generalizability of a single-center experience may be limited. Follicular findings in CCLE of the scalp are reported. We hypothesize that the basaloid aggregates are remnants of hair follicles that are no longer actively cycling.