Calciphylaxis, also known as calcific uremic arteriolopathy, is a rare but serious vascular alteration with a high rate of morbidity and mortality. The prevalence ranges between 1 and 4%of patients with chronic renal failure. This disease most frequently affects the elderly, women, Caucasians, and persons with diabetes or HIV. The pathogenesis remains unclear, but various risk factors are involved, including secondary hyperparathyroidism, elevated calcium x phosphorus product >55 mg/dl, normal or high blood calcium levels, and high doses of active vitamin D metabolites, etc.
Pathologically, this disease manifests as a small vessel vasculopathy in which there is mural calcification with intimal proliferation, fibrosis and eventually thrombosis of the affected vessel, resulting in ischemia of the irrigated tissue. Clinically, the disease manifests by subcutaneous nodules and extremely painful violet, purple or ecchymosis plaques, over a mottled or reticular erythema similar to livedo reticularis. In a few days these lesions progress to the formation of necrotic ulcers covered with black eschar. The diagnosis is suspected on the basis of history taking and physical examination. Therapeutic measures are ineffective and should be directed at controlling phosphorus and calcium and standardizing calcium x phosphorus product is< 55mg/dl. The use of active vitamin D metabolites should be avoided.