A case of warfarin skin necrosis despite enoxaparin anticoagulation in a patient with protein S deficiency.

Warfarin-induced skin necrosis is a rare complication associated with the use of oral anticoagulants. Most patients develop this at the initiation of therapy, often while still receiving intravenous unfractionated heparin (UFH). Recently, low-molecular-weight heparins (LMWHs) have gained wider use, providing an option for outpatient treatment of deep-vein thrombosis. The treatment protocols are similar to UFH, including the early initiation of oral anticoagulation with warfarin. A Medline search failed to reveal any cases of warfarin-induced skin necrosis while using a LMWH. We present a patient with protein S deficiency who developed warfarin skin necrosis despite appropriate anticoagulation with enoxaparin, and review the chemical and clinical difference between UFH and LMWH.