Scarring Alopecia in Localized Dystrophic Epidermolysis Bullosa: A Case Report and a Scoping Review.

Alopecia is a recognized complication of the epidermolysis bullosa (EB) group of blistering diseases, with diffuse and scarring alopecia seen in severe generalized EB. However, there is a dearth of literature characterizing alopecia in localized EB, with few reports of scarring and non-scarring alopecia in dystrophic EB (DEB). In this report, we present a case of a 58-year-old female with an eight-year history of pretibial DEB and a documented heterozygous COL7A1 mutation, who presented to the dermatology clinic with improving skin fragility after five months of topical beremagene geperpavec therapy, now noting gradual hair thinning on the vertex scalp over one year. Clinical examination revealed decreased hair density on the vertex and frontal scalp, with scattered sclerotic papules, without significant perifollicular scale or erythema. Two punch biopsies were obtained for histologic vertical and horizontal sections, revealing superficial and mid-dermal fibrosis encircling hair follicles at the infundibulum and isthmus, numerous fibrous stelae, a superficial perifollicular lymphocytic infiltrate with scattered follicular dyskeratotic keratinocytes, and preservation of sebaceous glands. Together, these findings were consistent with scarring alopecia with shared features of DEB and lichen planopilaris (LPP). We highlight the importance of recognizing scarring alopecia as a complication of DEB, with discernment for concomitant inflammatory etiologies that may co-occur, especially in a patient with a COL7A1 mutation.