Endocrine Abstracts

JOINT1793

Parathyroid adenomas are a common cause of primary hyperparathyroidism; however, giant parathyroid adenomas (GPA), defined as weighing more than 3.5 grams, are rare.

Case Presentation: We report the case of a 53-year-old woman who presented with severe, disabling bone pain, prompting medical evaluation. Laboratory tests revealed severe malignant hypercalcemia (146 mg/l), hypophosphatemia (24 mg/l), and markedly elevated parathyroid hormone (PTH) levels (1898 pg/mL). Initial management consisted of intravenous hydration (2–4 L/24h). Due to persistent hypercalcemia, treatment with zoledronic acid (4 mg) was initiated. Electrocardiography showed a bundle branch block without QT interval shortening. Neck ultrasound identified a large, well-defined, hypoechoic, hypervascularized parathyroid adenoma at the inferior pole of the right thyroid lobe, measuring 2.67 × 2.02 × 4 cm. Once calcium levels were stabilized, the patient underwent a successful parathyroidectomy. The excised adenoma weighed 6 g, and histopathological examination confirmed a benign parathyroid adenoma. Postoperatively, PTH levels significantly decreased (100 pg/mL), with notable clinical and biochemical improvement.

Discussion/Conclusion: This case highlights the importance of recognizing severe hypercalcemia as a potential indicator of GPA and underscores the essential role of surgical intervention in achieving favorable patient outcomes.