A 48-year-old woman with diet-controlled diabetes had extremity arthralgias, a purpuric rash and foot paresthesias, and eye pain and redness. Vital signs and results of laboratory testing including direct immunofluorescence were unremarkable; skin biopsy showed leukocytoclasia, erythrocytic extravasation, and fibrin in small blood vessel walls. What is the diagnosis and what would you do next?
Source: JAMA Online First