Coumarin Induced and Spontaneous Hemorrhagic Skin Necrosis

Abstract

Patients with coumarin induced skin necrosis presents with painful purpura and erythematous bluish swelling of the skin complicated by blister formation, hemorrhage and immanent gangrene. Coumarin induced hemorrhagic skin necrosis occurs within one week after initiation of coumarin treatment at time of prolonged INR caused by an imbalance within the vitamin K dependent anticoagulant and procoagulant factors with severe protein C and factor VII deficiency as compared to near normal factor II, X and IX. Treatment consists of vitamin K supplementation and short-term discontinuation of coumarin. Patients with pre-existing congenital protein C deficiency or acquired protein C deficiency due to vitamin K deficiency are at increased risk for the development of coumarin skin necrosis. In this report we described a case of coumarin induced hemorrhagic skin necrosis and a case of spontaneous hemorrhagic skin necrosis during an acute episode of severe vitamin K deficiency due to cholestasis in the absence of coumarin treatment. An imbalance within anticoagulant and procoagulant vitamin K dependent factors with severe acquired protein C and factor VII deficiency but still normal values of factor II, IX and X at time of prolonged prothrombin time (INR 5.0) due to severe vitamin K deficiency could be identified as the cause of spontaneous thrombo-hemorrhagic skin necrosis.