Calciphylaxis

QUESTION 22

A 51-year-old woman is evaluated by the dermatology consult service for a new painful purpuric rash on her legs. Her medical history is notable for end-stage renal disease, and she is on hemodialysis three times per week. The rash began on her left calf as a small dark purple area but has continued to spread and become more painful. On examination, there is a purpuric plaque with surrounding erythema and irregular, stellate borders, which is firm and exquisitely tender to gentle palpation (22).