Rare process usually begins between the third and tenth days of treatment with warfarin and occurs mainly in women with sharply demarcated erythematous, indurated and purpuric lesions.
Lesions may resolve or progress to formation hemorrhagic bullae with eventual necrosis and eschar formation.
The process is unrelated to dose or underlying conditions.
Common sites of involvement are the breasts, thighs, and buttocks.
The course of the illness is not altered by the discontinuation of warfarin.
Associated with protein C deficiency.
Causes a precipitous fall in protein C levels in heterozygotes for protein C deficiency with hypercoaguability and thrombosis in cutaneous microcirculation with areas of necrosis.
Treated with vitamin K and heparin.