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Abstract: SA-PO197

Uremic Leontiasis Ossea Case

Session Information

Category: Bone and Mineral Metabolism

  • 402 Bone and Mineral Metabolism: Clinical


  • Fakhredine, Sara, BSH, Manama, Bahrain
  • Alsaid, Jafar, Ochsner Medical Center, New Orleans, Louisiana, United States
  • Kumar, Teerath, BSH, Manama, Bahrain
  • Sheikh, Rayees Yousuf, BSH, Manama, Bahrain

Uremic leontiasis ossea (ULO) is a rare complication of untereated severe hyperparathyroidism in patients with ESRD. It is characterized by abnormal bone mineralization with severe and diffuse enlargement of the maxilla and mandible bones resulting in lion’s face features. Given the widespread use of dialysis, calcimimetics, and phosphate binders, ULO is now rare.

Case Description

A 37-yr-old woman with ESRD secondary to FSGS. She had developed secondary hyperparathyroidism. She was poorly adherent to her dialysis sessions and prescribed medications. Her condition progressed to tertiary hyperparathyroidism over 10 years with a parathyroid hormone (PTH) level of 1,249 pg/mL and a serum calcium of 12.3 mg/dL. She had refused to undergo parathyroidectomy and was not compliant to her treatment dispite multiple discussions. Her PTH increased to 5,814 pg/ml, serum calcium and serum phosphate were 8.8 and 3.9 mg/dl, respectively. Her complains were headach, dipplopia on lateral gaz, gum bleeding and nasal blockage. Over the course of 7 years, she sustained progressive facial changes with deformity of the maxillary and mandibular bones with widening of the interdental spaces (Image). Calciphylaxis, fractures of vertebra and right humerus ensued over the last two years. Maxillofacial computed tomography showed “pepper pot” appearance of skull. Parathyroid scan showed multiple nodules, the largest 3x3 cm. A DEXA scan revealed severe osteoporosis. The patient remains adamant not to have the surgery and the last PTH value of 3,476 pg/mL, serum calcium of 9.0 mg/dL and serum phosphate of 4.2 mg/dL.


ULO is a rare and disabling complication of tertiary hyperparathyroidism in ESRD. Without treatment, irreversible bony deformities can occur. Adherence to treatment is critical to optimize its prognosis.

The term was first used by by Kienböck in 1940. The treatment includes parathyroidectomy, percutaneous fine needle ethanol injection or Calcitriol in non-surgical candidates. Reconstructive surgery might be used to correct the bony deformities.