Endocrine Abstracts

JOINT2523

Introduction: Tertiary hyperparathyroidism (THPT) results from prolonged secondary hyperparathyroidism, often following hemodialysis, when the parathyroid glands become autonomous, leading to overproduction of PTH and persistent hypercalcemia. This condition may involve ectopic glands (thymus, mediastinum, or other locations), complicating diagnosis and treatment. Clinically, THPT manifests as severe hypercalcemia, vascular and tissue calcifications, osteopathy, and cardiovascular complications. When medical treatment (cinacalcet, vitamin D) fails, surgery becomes an essential option, particularly in cases involving ectopic glands.

Case Observation: A 20-year-old female patient with chronic kidney failure (on hemodialysis for 4 years) presented with a progressively developing swelling of the maxillary bone over the past 2 years. PTH levels were measured at 4028 pg/mL.

Renal ultrasound:Chronic nephropathy with simple renal cysts on the right kidney.

Cervical ultrasound:Two nodular formations in the mediastinal region suspected to be ectopic parathyroid nodules.

CT scan (thorax-abdomen-pelvis):Multiple axial and peripheral lytic lesions associated with signs of bone resorption, an expansive lytic lesion centered on the maxillary bone consistent with a brown tumor, fibrous dysplasia of the mandible and cranial vault, and homogeneous splenomegaly.

Discussion: Ectopic parathyroid glands, present in 14–45% of cases, pose diagnostic challenges that require precise localization using Tc99m-sestamibi scintigraphy or MRI. Surgical indications include refractory tertiary hyperparathyroidism unresponsive to medical treatment (cinacalcet, vitamin D), persistent hypercalcemia (>11 mg/dL) with complications (calcifications, osteopathy), and identified or suspected ectopic glands. Total parathyroidectomy with autotransplantation, combined with bilateral thymectomy and, if necessary, mediastinal exploration, is the optimal surgical strategy for these complex cases. This approach enables rapid reduction of PTH and calcium levels, significant clinical improvement, and prevention of long-term complications. A multidisciplinary approach involving endocrine surgeons, nephrologists, and radiologists is essential to ensure durable outcomes.

Conclusion: Surgery plays a central role in the management of tertiary hyperparathyroidism with ectopic glands. Accurate preoperative localization and appropriate postoperative management (calcium and vitamin D supplementation) are essential to minimize complications and ensure long-lasting outcomes.