Endocrine Abstracts

The incidence of recurrent primary hyperparathyroidism (PHPTH) (> 6 months from initial exploration) has been reported to be between 1–10%. Repeated neck explorations could be challenging for surgeons and ensuring normalised biochemistry is vital for peri-operative safety. Recurrent parathyroid adenomas can present with aggressive hypercalcaemia which can be challenging to control prior to surgery. We report a similar case below. A 72 year old lady had her first presentation of PHPTH in 2008 (Corrected Calcium = 3.23 mmol/l, PTH = 29.3 pmol/l). Parathyroid imaging showed a right inferior adenoma (1.5 × 0.6 cm³) reflecting a possible right parathyroid adenoma. The first surgery for parathyroidectomy needed to be abandoned in view of severe bradyarrhythmia (heart rate 37 due to complete heart block requiring pacemaker insertion). The second surgery was successful with removal of 3 parathyroid glands which confirmed two parathyroid adenomas and one hyperplastic parathyroid gland. Post-operative biochemistry normalised (Corrected Calcium = 2.51 mmol/l, PTH = 8.9 pmol/l). 10 years later the patient was referred to the endocrine team for symptomatic severe hypercalcaemia of 3.5 mmol/l. it was biochemically confirmed recurrent PHPTH with very high PTH levels (PTH = 65 pmol/l). Parathyroid imaging showed a left inferior giant parathyroid mass (4 × 2 × 2.7 cm) with mediastinal extension with displacement of oesophagus and possible infiltration into it. Given the high PTH levels, the size of the mass and refractory hypercalcaemia, it was discussed in MDT with suspicion of parathyroid carcinoma. Patient had significant cardiac history and hence normalization of calcium levels was mandatory for peri-operative safety. Despite repeated admissions for IV hydration and bisphosphonate infusions her calcium remained in range of 3–3.5 mmol/l. due to refractory hypercalcemia unresponsive to hydration and bisphosphonates, she was admitted to hospital 10 days prior to surgery. Her calcium was normalised by use of calcitonin subcutaneous injections along with conventional treatment. During surgery a large mass about 8 cm in size (7.8 × 2.6 × 0.6 cm³) was removed which was confirmed to be parathyroid adenoma with no evidence of malignancy. This case highlights the aggressive nature of recurrent parathyroid adenomas. Perioperative refractory hypercalcaemia can be effectively controlled by use of calcitonin. Patients with multi-gland disease should also be screened for genetic causes of primary hyperparathyroidism like multiple endocrine neoplasia (MEN).