Warfarin necrosis
The coumarin ( Syn: Warfarinnekrose, Marcumarnekrose ) is a rare side effect of anticoagulant therapy with a coumarin preparation. The incidence is less than 0.1% of patients treated with this group of substances.
It comes a few days after initiation of therapy too often pressure sensitive macular lesions that usually appear at first reddened. In the course of a few days, where they form an increasing bloody blisters or black coloration. The final stage is usually stall ( " necrosis ") of the affected skin district with scarring. Affected is usually the trunk.
The exact cause of coumarin is still unknown, suspected, an initial damage of the capillary wall with subsequent thrombotic occlusion of small capillaries. Cumarinnekrosen occur in women, in obese individuals, in initially high doses of coumarin preparation and in patients with a deficiency of protein C on probably heaped.
No specific therapy is not possible, this is limited to a local wound treatment, extended defects, possibly with skin grafting and possibly also with amputations.
A low dose of coumarin preparation of therapy and an overlapping treatment with heparin in the first days considered as an appropriate means to reduce the risk of coumarin. However, unfractionated heparin while coumarin in rare cases, cause skin necrosis.