1. Warfarin Induced Skin Necrosis BY: MOHAMMED ALSAIDAN

3. Warfarin induced skin necrosis (WISN) affects 0.01% to 0.1% of patients on warfarin 3 to 10 days after the initiation of therapy In areas with increased subcutaneous fat such as the abdomen, buttocks, thighs, legs, and mammary tissue 33% multiple sites.

4. Warfarin induced skin necrosis Acute onset of paresthesia and edema  petechiae and ecchymosis  well-demarcated hemorrhagic bullae within 24 hours  painful coagulative full-thickness skin necrosis with formation of deep subcutaneous ulcers

5. Warfarin induced skin necrosis VKAs Coumarin derivatives : Bishydroxycoumarin (Dicumarol) Warfarin (Coumadin®) Analog #42 (1945) of many coumarins synthesized by Dr Link and named by him as WARFarin for the Wisconsin Alumni Research Foundation and coumARIN

6. Pathophysiology

8. Histopathology Diffuse microthrombi within dermal and subcutaneous capillaries, venules, and deep veins Endothelial cell damage resulting in ischemic skin necrosis and marked RBC extravasation No vascular inflammation and arterial involvement

11. Management Early diagnosis and drug withdrawal improve prognosis (Fresh frozen plasma, vitamin K) +/- Heparin Systemic antibiotic Protein C concentrates Local treatment topical bactericidal agents surgical debridement +/- skin grafting, mastectomy, or amputation

12. Warfarin Again ? Controversy