| • | previously considered to be due to a "vasculitis" |
| • | best regarded as a "vasculopathy", in which occlusion of small dermal vessels by thrombin thrombi is the primary event |
histology:
| • | hyaline thrombi in the lumen of small vessels of the upper and mid-dermis |
| • | usually infarction of the superficial dermis, often with small area of ulceration |
| • | often extravasated RBC’s |
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