A case of Birt-Hogg-Dubé syndrome.

Birt-Hogg-Dubé syndrome (BHDS) is an autosomal dominant genodermatosis characterized by cutaneous hair follicle tumors (fibrofolliculoma or trichodiscoma), pulmonary cysts, and increased risk of renal neoplasia. The genetic alteration for BHDS has been mapped to chromosome 17p12q11, and the gene in this region has been cloned and believed to be responsible for the BHDS. Mutations in the BHD gene (also known as FLCN) have been described in the patients with BHDS. We present a case of a 30-yr-old Korean woman with multiple mildly pruritic papules on her face and neck area. The patient had several firm, flesh-colored, dome-shaped, papular lesions measuring between 2 to 5 mm. Except for a history of pneumothorax her medical records were not remarkable. Mutation analysis of the BHD gene was performed, and a novel deletion mutation (p.F519LfsX17 [c.1557delT]) causing truncation of the gene product, folliculin, was found in the exon 14. The actual incidence of BHDS is unknown, but it is most likely underdiagnosed. So it is imperative that doctors recognize the skin lesions of BHDS and institute proper screening to detect other manifestations of the disease. Here, we report a case of BHDS with a novel mutation, which is the first report in Korea.