Livedo vasculitis associated with regional cytophagic histiocytoses.

We report a 70-year-old woman who developed recurrent multiple ulcers and residual atrophic scars on her legs and feet. The histology showed fibrinoid material in the dermal vessel walls causing partial to complete occlusion of the lumina. Capillary tufting and dilatation were also noted in the dermis. There was no vasculitis or panniculitis. Extravasated red blood cells were seen throughout the dermis; these were engulfed by benign-appearing histiocytes around the dermal-fat junction. As she was generally well and there was no evidence of the presence of cytophagic cells in her extracutaneous organs, she was diagnosed with regional phagocytic histiocytoses supposedly triggered by extravasated red blood cells.