[Uremic Leontiasis Ossea: A Challenge in End-Stage Chronic Kidney Disease. About a Case].

Uremic leontiasis ossia (ULO) is a rare manifestation of renal osteodystrophy in) patients with end-stage chronic kidney disease (CKD) and secondary hyperparathyroidism (SHPTH). It occurs due to increased osteoclastic activity secondary to high plasmatic parathyroid hormone (PTH) levels. This leads to bone deformation with thickening and massive enlargement of the cranial vault, resulting in a leonine face appearance. Imaging such as CT scans of the head and neck can reveal bone remodeling, which aids in diagnosing ULO in patients with elevated PTH. Treatment requires a multidisciplinary approach, including medical management of SHPTH, parathyroidectomy, and osteoplasty under a maxillofacial surgery specialist to correct anatomical abnormalities.

Aim: Herein, we present a case report of a patient with ULO, demonstrating valuable insights into early recognition and multidisciplinary management of the disease.

Case report: A 39-year-old female patient with a past medical history of CKD on hemodialysis, hypertension, and SHPTH. The patient was admitted for total parathyroidectomy due to non-toxic multinodular goiter. Physical exam shows a nonpainful increasing bilateral growth of maxillary and mandibular bone, loss of nasolabial folds, and widening of the nares, resulting in a leonine appearance. Relevant laboratory exams showed a plasmatic PTH level of 4557 pg/ml. CT scan of the head and neck shows tunnel-like bones in the cranial vault consistent with ULO. The patient underwent total thyroidectomy and subtotal parathyroidectomy without complications. Laboratory exams on the first day post-surgery showed improvement in PTH plasmatic levels.

Conclusion: ULO is a rare disease and poses a diagnostic challenge. Early recognition of clinical features of ULO and elevated PTH levels in end-stage CKD patients is essential for a prompt diagnosis and appropriate treatment to avoid the consequences of ULO.