A Case of Solitary Trichodiscoma / 대한피부과학회지

Trichodiscoma are hamartomas of the dermal portion of the hair disc, and these are found as asymptomatic flesh- colored papules 1~3 mm in diameter, and they are usually located on the face, trunk and thigh. Histopathologically, this is characterized by non-encapsulated fibrovascular lesion with a myxoid stroma surrounded by folliculo- sebaceous units. Birt-Hogg-Dube syndrome, which develops multiple trichodiscomas with fibrofolliculomas and skin tags, has been described. The case of solitary trichodischoma is rare. We recently encountered a 29-year-old woman with a solitary, dome-shaped papule on the right thigh. After histopathologic examination, the lesion was diagnosed as trichodiscoma.

A Case of Birt-Hogg-Dube Syndrome

Birt-Hogg-Dube 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.

A Case of Solitary Trichodiscoma / 대한피부과학회지

Trichodiscoma is a small benign fibrovascular tumor of the dermal part of the hair disc, haarscheibes. Trichodiscomas are found as asymptomatic skin-colored papules, 1-3 mm in diameter, usually on the face, upper part of the trunk and sometimes the extremities. Histopathologically, a sharply defined fibrovascular lesion with myxoid stroma is related with an adjacent hair follicle. In cases reported thus far, there have been multiple lesion, with some reports demonstrating transmission on a dominantly inherited basis. We present here a case of solitary trichodiscoma involving a patient with no familial involvement.

Multiple Trichodiscoma:the First Case Report in China / 中华皮肤科杂志

Objectives To report the first case of multiple trichodis coma in China.A 31-year-old man presented with multiple,broomcorn grain to r ed bean-sized,skin-colored,firm papules on the right lower extremity for 15 years,and similar lesions on the left knee and lower leg for about one year.T he lesions were asymptomatic.Methods and Results Histopathology showed acanth osis of epidermis,proliferation of fine reticulate collagen fibers and depositi on of focal mucinous proteins in upper dermis.Small blood vessels and nerve fib ers were increased,and proliferation of elastic fibers was localized in the hai r follicles and around some rete ridges.Proliferated hair follicles were seen i n the margins of the lesions and extended down in a collar-like pattern.Ultra structurally,Merkel cell-axon complex was located in the overlying basal lami na of the epidermis.Myelinated nerve fibers were seen in the upper dermis.Bloo d vessel alterations were found under electron microscopy,some basal laminae of blood vessels exhibited laminated structure,proliferation of fibrous component,and thickened wall of blood vessels were observed.Conclusions The disease is rare.It is a hamartoma originated from hair disk.