Ulcerated lesions on shins

CASE #1

A man, aged 68 years, presented with ulcers on his shins of about 2 months. They began as retiform-appearing purple patches that would ulcerate and form hemorrhagic or necrotic crusts. The lesions were excruciatingly painful and tender. He had type 2 diabetes and ESRD, and had been on hemodialysis for 10-plus years. He had a history of low parathyroid ...