Endocrine Abstracts

A 79-year-old female was admitted with general decline, polydipsia, polyuria, decreased appetite and constipation. Her family reported mobility decline over past six months and confusion over past few days with weight loss. She had hypertension on Amlodipine and renal impairment was only detected when she recently moved to UK from Jamaica. An incidental finding of hypercalcaemia was found with an adjusted calcium of 3.03, PTH 79.8, vitamin D 33 and phosphate 0.41. The initial impression was tertiary hyperparathyroidism secondary to chronic kidney disease. This was managed with intravenous hydration and furosemide aiming for a urinary output of 100-150mls/hour. Her low eGFR of 17 was a contraindication for bisphosphonates treatment. Her Vitamin D was replaced & her calcium improved with hydration but rose up to 3.15 a week later with a marked increase in PTH level to 172. She was reviewed by Endocrine team, and patient had a 3 cm right sided neck mass felt on palpation. She had a high urine calcium: creatinine ratio of 0.71 with normal thyroid function tests, serum ACE and negative myeloma screening. A Neck USS showed a well-defined 2.9 cm right thyroid lobe U3 nodule and 2.4 cm left sided lesion likely to be parathyroid in origin while a SESTAMIBI scan suggested a left sided parathyroid adenoma and intense uptake in the right thyroid lobe. FNA performed revealed right thyroid oncocytic neoplasm with microfollicles, Thy3f. The left nodule was consistent with parathyroid lesion. Her calcium increased again despite satisfactory hydration and furosemide. She was thus commenced on Prednisolone with PPI cover alongside intravenous hydration. Cinacalcet was subsequently started following SESTAMIBI with good response, with her Calcium level going down to 2.70 & staying within the normal range. She was discussed at the Endocrine MDT, total thyroidectomy with level 6 dissection on the left was planned with a suspicion of parathyroid cancer. Histology pending, to discuss results. Points for discussion: Parathyroid carcinoma despite being a rare endocrine malignancy and an uncommon cause of PTH-dependent hypercalcemia needs to be considered in the setting of refractory hypercalcemia and very high PTH levels. It is difficult to distinguish between atypical parathyroid adenomas and parathyroid carcinomas and surgery is indicated for tissue diagnosis. Treatment of hypercalcemia and role of glucocorticoids; prednisolone is very effective acting within 2-4 days. Bisphosphonate use is limited in patients with renal impairment. Calcimimetics can be used if poor response to other treatments.