Poikilodermatous plaque-like hemangioma: A benign vasoformative entity with reproducible histopathologic and clinical features.

Poikilodermatous plaque-like hemangioma (PPLH) is a recently described benign vasoformative entity with only 16 cases reported to date. We present an additional case of a 90-year-old male who presented with a 2-year history of a relatively large, asymptomatic, atrophic plaque on his left buttock. The lesion was initially smaller and grew before stabilizing in size.

Current and emerging concepts in atopic dermatitis pathogenesis.

Atopic dermatitis is a common skin disorder with a complex, evolving pathogenesis. Research on the pathogenesis has shifted from focusing primarily on generalized immune system abnormalities in T helper 1/T helper 2 (T1/T2) activity to more targeted immune and skin barrier abnormalities contributing to the overall phenotype. Specific signaling pathways recently implicated in atopic dermatitis include production of interleukin (IL) 4 and IL-13, which promote immunoglobulin E production, T17 and T22 cells, and production of cytokines.