Association between calciphylaxis and inflammation in two patients on chronic dialysis

The pathogenesis of calciphylaxis, which has a rising incidence in the chronic dialysis population and a high mortality rate, is poorly understood. Abnormalities in the calcium-phosphorus-parathyroid axis are clinically related to calciphylaxis, but alone, they cannot explain this condition. Here, we present two patients who had chronic inflammatory conditions and hyperparathyroidism and who developed calciphylaxis. A 41-year-old white woman on hemodialysis following scleroderma, hepatitis C, liver transplant, and failed kidney transplant, developed progressive ulcerative lower extremity calciphylaxis lasting more than 3 years. She had evidence of severe hyperparathyroidism and elevated serum C-reactive protein (CRP). A 39-year-old white woman on continuous ambulatory peritoneal dialysis for 6 years for renal failure secondary to lupus nephritis, with sustained lupus activity during the dialysis period, developed rapidly progressing ulcerative calciphylaxis of the lower and upper extremities not responding to adequate treatment of hyperphosphatemia and hyperparathyroidism. Her condition culminated in death within 2 months of the appearance of the skin lesions. Her serum CRP was elevated on a sustained basis before the development of the calciphylaxis and rose to a very high level after appearance of the skin lesions. Inflammation may assist in the development of calciphylaxis through depression of serum levels of fetuin-A, an endogenous inhibitor of calcification that is also a negative acute-phase reactant. The interactions between inflammation-mediated changes in the levels of endogenous inhibitors of calcification and abnormalities in calcium-phosphorus metabolism merit intensive study in the future as potential mechanisms of calciphylaxis.