Erythrocyanosis (Q87455)

Erythrocyanosis is a persistent, dusky erythema occurring at sites with a thick layer of underlying subcutaneous fat, such as the thighs and lower legs. Erythrocyanosis is seen less commonly on the buttocks and arms. It is exacerbated by cold and therefore usually more prominent during the winter. It has been hypothesized that the subcutaneous fat in these sites acts to insulate the superficial vessels from the warmth of the underlying blood supply, thus rendering them susceptible to cold exposure.