A man in his 60s presented to the emergency department for left flank pain of 1 week’s duration. His medical history included severe peripheral arterial disease and a remote history of ruptured abdominal aortic aneurysm. Three months before presentation, he underwent percutaneous endovascular stenting of a left popliteal artery aneurysm. Physical examination of the left flank showed a well-defined 5 × 12-cm purpuric patch with a darker stellate patch within it (Figure, A). Two punch biopsy specimens were obtained (Figure, B and C).