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Kidney Week

Abstract: FR-PO441

Tumoral Calcinosis in Hemodialysis Patient

Session Information

Category: Dialysis

  • 701 Dialysis: Hemodialysis and Frequent Dialysis


  • Griveas, Ioannis, Dialysis Unit "Nefroiatriki", Athens, Greece

Uremic tumoral calcinosis is an uncommon but serious complication of end-stage renal disease. It is characterized by massive extraosseous calcification in periarticular tissues, leading to limited range of joint movement, pain, and skin ulceration.

Case Description

A 52-year-old man developed a progressively enlarging painless mass on the posterior surface of the right leg and on the back surface of the right shoulder with limited range of flexion following 5 years of hemodialysis. Μagnetic resonance showed amorphous, cystic, and multilobulated calcification. Pathology report revealed tumoral calcinosis. We started intensifying hemodialysis program (5 days per week, 4 hours each session), low calcium bath , aggressive control of hyperphosphatemia, initiation of cinacalcet, antibiotics and administration of sodium thiosulfate 25 mg i.v per each session. After 6 weeks we noticed significant reduction in the magnitude of the masses and in 8 weeks complete resolution. We turned hemodialysis schedule to 3 times a week and continued to have close monitoring of the patient.


Effective treatment options for tumoral calcinosis remain elusive. The primary focus of therapy should be to optimize calcium and phosphate homeostasis. Avoidance of a positive calcium balance should be a high priority. Experienced nephrologists recommend a course of dialysis 5–7 days per week for the first couple weeks of treatment, with the duration of this intensified dialysis therapy depending on clinical response.Sodium thiosulfate is a chelating agent that has antioxidant activity and increases activity of endothelial nitric oxide synthetase. Sodium thiosulfate is believed to act by dissolving insoluble tissue calcium salts to form calcium thiosulfate, which is many thousand times more soluble than many other calcium salts.