Incidence and characteristics of calciphylaxis in Martinique (2006-2012)

Calciphylaxis is a rare and severe disease with an annual incidence of around 1 % in dialysis patients. The main study aim was to determine its incidence in Martinique, where there is a significant population of patients on dialysis. All patients diagnosed with calciphylaxis between 2006 and 2012 and living in Martinique were included, retrospectively. Social, demographic, biological, anatomic, pathological, histological and outcome data were analysed. Fifteen patients were included (8 women, 7 men). The incidence of calciphylaxis in this population was about 4.62/1,000,000 inhabitants per year. All patients presented very painful skin ulcerations and necrosis, chiefly on the lower extremities in 53.3 % of cases. All patients were on haemodialysis and two had undergone renal transplantation. Fourteen of the 15 patients were presenting secondary hyperparathyroidism, 12 had hypertension, 9 peripheral arterial disease, 8 obesity and 8 diabetes mellitus. Raised calcium and phosphorus were noted in 8 patients, with hypoalbuminaemia in 9 patients. Treatment with sodium thiosulfate was given for 8 patients, and was beneficial for all after a mean duration of 3.4 months. After 6 months of follow-up, 8 of the 15 patients were cured, 1 showed improvement and 6 had died. To our knowledge, this is the first study to examine the incidence of calciphylaxis in the general population. The relatively large number of patients could be accounted for by the high number of comorbidities in end-stage renal disease patients in Martinique, including obesity, diabetes, hypertension and arteritis. Treatment with sodium thiosulfate was beneficial for 8 patients.