Nonpalpable purpura within a setting of anticoagulant therapy and metastatic carcinoma

The anticoagulant warfarin can produce a skin necrosis that is clinically indistinguishable from the skin necrosis caused by purpura fulminans associated with disseminated intravascular coagulation (DIC) and heparin-induced thrombocytopenia (HIT). The similar clinical and histologic findings observed in each of these skin necroses create a challenge for diagnosis and eventual treatment. The authors report a patient with significant risk factors for warfarin-induced skin necrosis, DIC, and HIT presenting with painful, purpuric patches beginning on her feet and extending proximally before becoming hemorrhagic bullae on her lower extremities.