Nonuremic Calciphylaxis: A Rare and Unexpected Diagnosis of Necrotic Ulcers

Calciphylaxis is a rare and devastating condition found almost exclusively in patients with end-stage renal disease. Nonuremic calciphylaxis, an even more rare diagnosis, occurs in patients with preserved kidney function. We present a fatal case of nonuremic calciphylaxis with delayed and unexpected diagnosis despite early biopsy and testing. The patient presented with a 2-month history of painful ulceration to the left leg. Early biopsy was negative for calciphylaxis. Laboratory tests were negative for renal disease and autoimmune disorders. There was elevated parathyroid hormone (96 pg/mL) 3 months after initial presentation and documented cobalamin deficiency. The patient went on to develop wounds to both legs and her thighs. A second biopsy of a left thigh wound by means of the dermatology service revealed calciphylaxis. The purpose of this case report is to raise awareness of calciphylaxis as a differential diagnosis for chronic necrotic skin ulcers, especially in patients with preserved renal function and those on warfarin therapy.