Extragenital bullous lichen sclerosus: A case report and literature review

Abstract Lichen sclerosus (LS) is a chronic dermatosis characterized by atrophic white papules or plaques, most commonly occurring on the anogenital skin. Blisters have been rarely described developing in the background of extragenital LS. A 74-year-old woman with a 4-year history of sclerotic patches on the trunk showed a flaccid bulla on the lower back for 3 months. The histopathological finding of the skin biopsy was consistent with the diagnosis of bullous LS. In this paper, we present this uncommon case, review the literature on extragenital bullous LS, discuss the pathogenesis, and provide some treatment options for the case.