Discrete papular lichen myxedematosus with an unusual segmental presentation.

Discrete papular lichen myxedematosus, a subtype of localized papular lichen myxedematosus, is an idiopathic cutaneous mucinosis. It typically presents symmetrically, involving the trunk and extremities. We report on an unusual case of discrete papular lichen myxedematosus with a segmental presentation. An otherwise healthy 23-year-old man presented with a gradual accumulation of asymptomatic papules on the lower abdomen over the previous year. Physical examination revealed multiple, well-defined, discrete and coalescing, 1-5mm, smooth, indurated, dark brown, slightly erythematous papules, with variable surrounding hyperpigmentation, involving the skin of the right lower abdomen in a segmental distribution (Figure 1). A punch biopsy specimen was obtained. Histopathological examination revealed mucin deposition in the superficial to mid-reticular dermis, moderate proliferation of fibroblasts, and an inflammatory infiltrate composed of plasma cells and lymphocytes (Figures 2A, B). The clinical and pathologic features were consistent with discrete papular lichen myxedematosus. The laboratory work-up, including a complete blood count with differential and liver function tests,