ODP078 An Unsolved Mystery of Hyperparathyroidism for 12 Years

INTRODUCTION: Primary hyperparathyroidism (PHPT) is characterized by hypercalcemia and elevated or inappropriately normal levels of parathyroid hormone (PTH). It results from excessive secretion of PTH from one or more of the parathyroid glands. The number and location of the parathyroid glands can be variable. The organogenesis of the parathyroids determines the definitive location in adulthood. We hereby present an interesting case of primary hyperparathyroidism caused by the ectopic parathyroid gland. Clinical case 85-year-old Black female with papillary thyroid cancer status post total thyroidectomy and RAI in 2011, hypertension, hyperlipidemia, osteoporosis, long standing PHPT referred to ER for hypercalcemia from a physician's office. A review of the system was significant for unintentional 40 lb. weight loss over the past several months and increased urinary frequency. She denied confusion, abdominal pain, constipation, paresthesia. On physical exam she was afebrile, BP 144/63 mm Hg, pulse 56/min and respiratory rate of 18. The rest of the detailed physical examination was unremarkable. She was initially diagnosed with primary hyperparathyroidism in 2009 based on PTH- 196 pg /ml (n 10-65 pg/ml), and corrected calcium- 11. 0 mg/dl (n 8.5-10.1 mg/dL) . Laboratory on this admission (2021) revealed PTH - 411.8 pg/ml (n 10-65 pg/ml), corrected calcium - 12.9 mg/dL (n 8.5-10.1 mg/dL) with albumin 4 g/dl (3.4-5. 0 g/dL), ionized calcium-7.30 mg/dL (n 4.5-5.3 mg/dL), 1,25-(OH) 2 vitamin D level -50.2 pg /mL (n 20-82 pg/mL),25-(OH) vitamin D level of 37.2 ng/mL (n 30-100 ng/mL) and GFR-40 mL/min/1.73m 2 (n >=60. 0 mL/min/1.73m 2). She underwent a total of 4 Sestamibi scans and 1 MRI chest with and without contrast since 2009 that failed to localize defective parathyroid gland . But on this admission an incidental finding of right neck mass measuring 3. 0×1.2×2.7 cm was noted in MRI cervical spine that led to US head and neck soft tissue. It showed a solid and cystic mass with a concern for ectopic parathyroid gland posterior to the right submandibular gland. ENT was consulted, and the patient underwent right neck exploration with the removal of the neck mass. Pathology resulted as hyperplastic parathyroid tissue most congruent with a parathyroid adenoma. CONCLUSION: Ectopic parathyroid glands occur in approximately 15% of patients with PHPT. Embryologically, the third pharyngeal pouch gives rise to the inferior parathyroid glands, and the superior parathyroids arise from the fourth pharyngeal pouch. It can occur from the angle of the mandible to the mediastinum according to the developmental and migratory aberrations. Parathyroidectomy remains the definitive cure for PHPT and is recommended in all symptomatic patients. Presentation: No date and time listed