Birt-Hogg-Dubé Syndrome

Abstract

In 1977, Birt, Hogg, and Dubé described a kindred of 70 individuals, some of whom presented with small skin-colored papules, predominantly of the face. These developed in early adulthood, and were noted to be inherited in a dominant pattern (1). The histomorphology of the papules was described as “abnormal hair follicles with epithelial strands extending out from the infundibulum of the hair follicle into a hyperplastic mantle of specialized fibrous tissue.” The authors applied the term fibrofolliculoma to these lesions. Also described in these patients were trichodiscomas and acrochordons. Trichodiscoma is a benign tumor of perifollicular mesenchyme. It is thought to represent a proliferation of the haarscheibe (hair disk), a perifollicular “richly vascularized dermal pad covered with thick epidermis containing Merkel cells and supplied by a thick myelinated nerve the branches of which end at the lower epidermal surface and on the blood vessels of the dermal pad” (2). It is composed of a dermal interfollicular proliferation of spindle cells in a loose connective tissue matrix with varying amounts of mucin. It may have an orientation parallel to the skin surface.