Sodium thiosulfate: an emerging treatment for calciphylaxis in dialysis patients

Calciphylaxis is a rare but life-threatening complication seen in dialysis patients. We report a case with calciphylaxis and severe secondary hyperparathyroidism. Sodium thiosulfate (STS) was used for treatment in this case. The painful skin ulcers improved significantly soon after treatment, with a slight reduction in the calcium-phosphorus product. Total parathyroidectomy was carried out 6 months after the STS therapy, which successfully solved hyperparathyroidism and the high calcium-phosphorus profiles. Until now, no recurrence of calciphylaxis has been observed during the more than 7 years of follow-up. STS, as a chelating agent for calcium and iron, is an emerging treatment option for calciphylaxis; however, the mechanisms of STS in treating calciphylaxis are not clear. Our case demonstrates that STS treatment did not work through normalizing calcium-phosphorus profiles, although to optimize hyperparathyroidism and to control calcium and phosphorus levels is clearly part of the general treatment of calciphylaxis. The literature on STS treatment for calciphylaxis in dialysis patients was also reviewed.