Wcn24-1997 Sodium Thiossulfate Treatment for Calciphylaxis: Is There an Optimal Duration of Therapy?

Calciphylaxis is a rare and serious condition characterized by vascular calcification, occlusion of microvessels in the dermis, subcutaneous adipose tissue, visceral organs and in the musculature1. The pathophysiology is uncertain; however it is believed that occlusion of cutaneous blood vessels occurs due to calcification within the media layer of the vessel walls with proliferation of endothelial cells and fibrosis under the intima that evolve with ischemic lesions. Vascular smooth muscle cells transform into osteoblast-like cells capable of producing and depositing hydroxyapatite crystals in response to hyperphosphatemia, hypercalcemia and hyperglycemia2.The estimate annual incidence of calciphylaxis is 3 cases per 10.000 patients on hemodialysis in the United States and 4 cases per 10.000 patients in Europe.3Studies have suggested the major risk factors for the development of calciphylaxis are chronic kidney disease (CKD) and secondary hyperparathyroidism (sHPT).