REPORT OF A CASE
A 63-year-old woman with a history of hypertension, diabetes, and end-stage renal disease was admitted with complaints of joint stiffness distally, decreased sensation in a glove-stocking distribution, and pain in her extremities distally. Her renal function had been deteriorating and dialysis was initiated. Results of the physical examination revealed purplish mottling of the skin of her lower extremities. This quickly progressed to painful subcutaneous nodules with eventual ulceration and necrosis. Several digits, as well as the left lateral malleolus and the dorsum of the left foot, became gangrenous with time (Figure). Laboratory studies disclosed the following values: hemoglobin, 77 g/L; hematocrit, 0.25; white blood cell count, 8.7 × 109/L; platelet count and cell differential, normal; erythrocyte sedimentation rate, 126 mm/h; serum urea nitrogen, 21 mmol/L; creatinine, 434 μmol/L; calcium, 2.27 mmol/L; phosphate, 2.49 mmol/L; parathyroid hormone, 9.9 ng/mL (0.16 to 0.96 ng/mL); antinuclear