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Calciphylaxis typically affects patients with end-stage kidney disease (ESKD) treated with dialysis. Incidence amongst patients on hemodialysis varies worldwide, ranging from 0.35 % in the USA to less than 0.03% in Japan. A report suggests an increasing incidence in the USA. The incidence in kidney-transplant recipients and in patients without ESKD, including among those with earlier stages of chronic kidney disease, is unknown. Approximately 60 to 70% of patients with calciphylaxis are women.

The average age at the time of diagnosis is reported between 50 to 70 years; very few patients are children. Patients with calciphylaxis typically present with painful skin lesions. The pain is typically severe and there is associated tactile hyperesthesia. The initial manifestations may include skin induration, plaques, nodules, livedo, or purpura. The initial lesions rapidly progress to stellate ulcers with black eschars. Sepsis originating from the resultant wounds is considered the most common cause of death. Rarely, diffuse precipitation of calcium in viscera occurs (mainly in the heart or lungs, but also in the stomach or kidneys) which may lead to fibrosis and thrombosis, and eventually tissue necrosis. Depending on the affected organ, patients may present with dyspnea, cough and respiratory failure or acute heart block and subsequent sudden cardiac death. More than 70% of patients with calciphylaxis require hospitalization for severe ulcers.

The exact pathogenesis of calciphylaxis remains unclear. In addition to ESKD, warfarin use has been described as a major risk factor for calciphylaxis.

Diagnosis is suspected on clinical presentation. Skin biopsy may facilitate exclusion of conditions that mimic calciphylaxis.

Differential diagnosis includes warfarin necrosis, peripheral arterial disease, and oxalosis.

There is no approved treatment for calciphylaxis. Treatment focuses on pain control, wound management, and mitigation of risk factors. Off label treatments like sodium thiosulfate are frequently used clinically.

Quality of life of patients with calciphylaxis is extremely poor. Once calciphylaxis develops then the patients suffer from substantial morbidity related to pain, wounds and limited mobility, and many die within the first year of disease onset.