Background Calciphylaxis is a rare and potentially life-threatening condition. It is thought to result from arterial calcification causing complete vascular occlusion and subsequent cutaneous infarction. Most often, it is a complication of end-stage renal failure or hyperparathyroidism. This condition may be present in up to 4% of end-stage renal disease patients. The clinical picture is typically characterised by very painful skin lesions and ulcerations following calcification and occlusion of small cutaneous arterioles. Recently some evidence supports the use of intravenous sodium thiosulfate (STS) (Hayden M.R. et al, Calciphylaxis: calcific uremic arteriolopathy and the emerging role of sodium thiosulfate, Int Urol Nephrol 2008;40:443–451)

Purpose This abstract focuses on a case report of calciphylaxis successfully resolved with IV STS, as randomised controlled studies on STS efficacy are lacking.

Materials and Methods We report a case of calciphylaxis in a 77-year-old white woman with CKD. The acute presentation was seemingly precipitated by a high calcium-phosphorus product. As the patient was already taking bisphosphonates and phosphate binders, STS was suggested as a good treatment alternative. STS was administered intravenously using 25 g diluted in 100 cc of normal saline during dialysis.

Results The calciphylaxis episode was related to a high calcium-phosphorus product (P*Ca = 73), besides a high increase of parathyroid hormone (800 pg/ml). Clinical signs included cutaneous infarction and pain (photo is included). Four months after the initiation of STS injuries began to improve (photo is included) and the P*Ca was reduced but still remained high (P*Ca = 60). The parathyroid hormone level continued the same. The patient is still on IV STS treatment.

Conclusions Current calciphylaxis treatments alternatives aim to lower the serum calcium phosphate concentration thereby preventing, or even reversing, calcium phosphate oversaturation, precipitation and, finally, calcification. Administration of IV sodium thiosulfate, which sequesters calcium ions to form highly soluble calcium thiosulfate complexes, can prevent calcium phosphate precipitation.

No conflict of interest.