Lichen aureus: a hemosiderin tattoo associated with perforator vein incompetence

We present evidence that lichen aureus results from extravasation of red blood cells into the dermis caused by incompetence of an underlying perforator vein. The sudden appearance of the lesion suggests a "blow out" of the microvasculature of the lower dermis caused by failure of the valves in the perforator vein. This incompetence of the perforator vein induces a permanent reversal in normal blood flow. The consequent continuous high pressure in the cutaneous microvasculature is responsible for long-term leakage of red blood cells. Digestion of the extravasated red cells by macrophages leaves an "auto-tattoo" of insoluble hemosiderin granules, which produce the distinctive golden or burnt orange color of lichen aureus.