Endocrine Abstracts

Introduction: Tertiary hyperparathyroidism (THPT) is not uncommon in patients with secondary hyperparathyroidism after successful renal transplantation. It occurs up to 25% of these patients one year after transplantation despite renal function improvement. It can be developed due to the autonomous function of at least one parathyroid gland and leads to overproduction of parathyroid hormone (PTH). Tertiary hyperparathyroidism mostly reveals diffuse or nodular pattern of chief cell hyperplasia of the parathyroid glands which eventually leads them to adenomatous transformation. The THPT results in significant metabolic complications and symptoms, especially in patients who have had kidney transplants and are taking immunosuppressive therapy. Related symptoms include pruritus, severe osteodynia, pathologic fractures, memory loss, concentration difficulties and feelings of depression.

Case Report: A 35-year-old female who was known to have secondary hyperparathyroidism and a history of renal transplantation was admitted to our hospital due to hypercalcemia on routine blood tests. The patient underwent superior and inferior right parathyroidectomy and left inferior parathyroidectomy. Histological examination showed an adenoma measuring 3.6 cm. of the right inferior parathyroid gland and hyperplasia of the left inferior and right superior parathyroid glands, suggesting THPT. The level of serum and serum calcium were normalized after the surgery.

Conclusion: Patients with THPT commonly have significant symptoms and metabolic complications that improve after parathyroidectomy. Parathyroidectomy is the current recommended intervention to cure the disease. Successful surgical treatment results in a dramatic reduction in PTH levels and improvement of clinical symptoms especially bone pain. It is also associated with better patient survival. However, Cinacalcet is an alternative medical treatment for subgroup of patients in whom surgery is deemed inappropriate. Determining the optimal treatment for the individual patient is challenging for nephrologists and endocrine surgeons.