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

ABSTRACT

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.