Final answer:
The main difference between warfarin-associated calciphylaxis and warfarin skin necrosis is the location of the lesions. Calciphylaxis involves calcification of vessels leading to skin necrosis in fat-rich areas, while warfarin skin necrosis occurs due to depletion of clotting factors. The former does not respond to vitamin K unlike the latter.
Step-by-step explanation:
Warfarin-associated calciphylaxis and warfarin skin necrosis are both serious complications associated with the use of warfarin, but they differ in several aspects. Warfarin-associated calciphylaxis is typically characterized by the calcification of small and medium-sized vessels leading to ischemia and skin necrosis, often with painful lesions predominantly located on the fat-rich areas of the body. On the other hand, warfarin skin necrosis tends to present within days of starting warfarin therapy, usually affecting areas with high fat content such as the breasts, thighs, or buttocks, with skin necrosis occurring due to the transient hypercoagulable state caused by the rapid depletion of vitamin K-dependent clotting factors. Unlike warfarin skin necrosis, calciphylaxis often does not respond to vitamin K administration and is associated with a higher mortality rate.
The correct answer to the question is a. Location of lesions.