Sudden Onset of Painful, Dark Lesions – Let’s Diagnose

A 60-year-old woman went to the doctor after noticing sudden onset of extremely painful, dark areas that had developed on her legs over the course of a few days. On examination, there were violaceous and dark brown, retiform plaques, some depressed and some crusted, over the legs. The patient had a history of diabetes, hypertension, and chronic renal insufficiency for which she required hemodialysis.

Is it polyarteritis nodosa, calciphylaxis, cryoglobulinemia or panniculitis?

Can you diagnose the patient? Use the Differential Builder in VisualDx to help you.