A Case of Bullous Lichen Sclerosus et Atrophicus

Lichen sclerosus et atrophicus (LSA) is a benign, chronic inflammatory dermatosis that usually affects the female genitalia. It may also involve any other areas, and it is rarely seen on the face, oral mucosa and palm and sole. The lesion of LSA primarily occurs as a whitish or yellowish papule, and later it becomes a well-defined plaque. However, bullous LSA, which has a localized or generalized form, occurs as a rare variant of LSA. The exact prevalence of bullous LSA is uncertain. It generally involves not only the genitalia, which is vulnerable to trauma, but also extragenital sites. We present here a case of extragenital LSA with bullae on the upper back of a 33-year-old female. Histologic examination revealed hyperkeratosis, atrophy, vacuolar alteration of the basal layer and homogenization of the collagen in the upper dermis. In addition, increased collagen bundles and lymphocytic infiltration around the vessels in the lower dermis were also noted.