Calciphylaxis: diagnosis and clinical features

Calciphylaxis is a relatively rare disease, observed mainly in patients on dialysis, associated with high mortality rates, and characterized by painful skin ulceration. The pathogenesis of calciphylaxis is virtually unknown, although several risk factors, including warfarin therapy, hypoalbuminemia, and disturbances in calcium-phosphate metabolism, have been reported. The prevalence of calciphylaxis in Japan is likely to be less than 1:10,000 dialysis patients per year based on our nationwide survey in 2009. However, the results of the survey also showed that about 60 % of nephrologists in Japan are not familiar with the disease itself and it is highly likely that calciphylaxis is being overlooked. To facilitate recognition of calciphylaxis, we have proposed diagnostic criteria. At present, there is no specific therapy for calciphylaxis and general supportive measures, especially antibiotics for the accompanying infection and wound care, are important. Recently, sodium thiosulfate has been increasingly used to treat calciphylaxis and its efficacy should be evaluated by large clinical trials.