A 30 y.o. male presents with leg pain

his leg is pictured below

what is wrong?

Our patient had calciphylaxis. This is a serious disease where calcium accumulates in arteries in fat and skin.  This causes tissue necrosis and painful skin ulcers. It was first described in 1898 in association with renal failure. It is not clear why only 1-4% of patients with renal failure get calcium deposition.  The mortality is 60-80% in those with ulcerative disease.

An elevated calcium phosphorus product is associated with the disease. The RANK ligand(receptor activator of nuclear factor kB and osteoprotegerin appear to regulate skeletal and extraskeletal mineralization and appears to play a role in calciphylaxis. In addition, hypercoagulable conditions , including protein C and protein S have been described in a number of patients. Use of iron dextran, elevated aluminum levels, and warfarin use have also  been associated with calciphylaxis.

ulcers often lead to sepsis in calciphylaxis

The differential diagnosis would include pemphigoid, vasculitis,  necrotizing fasciitis, pyoderma gangrenosum and vibrio vulnificans.  Metastatic pulmonary calcification can also occur in tissues like the lungs, again related to secondary hyperparathyroidism  in chronic renal failure.

Treatment consists of phosphate binders,sodium thiosulfate, parathyroidectomy and frequent dialysis. Our patient received frequent dialysis and intralesional sodium thiosulfate as well as IV sodium thiosulfate. He slowly improved and is being scheduled for parathyroidectomy.

Gipstein RM, Coburn JW, Adams DA. Et al. Calciphylaxis in man.  A syndrome of tissue necrosis and vascular calcification in 11 patients with chronic renal failure. Arch Intern Med. 1976 Nov. 136(11):1273-80.

Zhou Q, Neubauer J, Kern JS, Grotz W, et al. Calciphylaxis . Lancet 2014 Mar 22.383(9922):1067.

Lai G, Nowell AG, Liao J, Sugg SL , et al. Determinants of survival in patients with calciphylaxis: a multivariate analysis. Surgery. 2009 Dec. 146:1028-34.