Endocrine Abstracts

A 77-year-old lady presented with reduced conscious state, dysphasia and profound confusion on a background of behavioural change and anorexia over the previous 10 days. She was previously independent with history of hypertension controlled on atenolol (100 mg). She was significantly hypertensive 200/100. Her serum calcium was elevated at 4.01 mmol/l (2.05–2.60). The serum parathyroid hormone (PTH) was also significantly elevated at 26 pmol/l (0.5–6.4) consistent with primary hyperparathyroidism. In view of her neurological state, a brain CT scan was performed which did not show any acute abnormality. She was aggressively hydrated with i.v. fluids followed by pamidronate. Her serum calcium improved to 3.29 mmol/l with improvement in drowsiness and blood pressure but with persistent confusion. On day 7 of her admission she was commenced on cinacalcet (30 mg b.d.) while undergoing investigations to localise a parathyroid adenoma. Over the next 1 week her serum calcium gradually normalised and was 2.57 mmol/l on day 15 with significant improvement in her confusion. However, her serum calcium started to rise again to 2.90 mmol/l over the subsequent week requiring increase in cinacalcet dose to 60 mg b.d. which maintained her serum calcium around 2.7 mmol/l but after a further 1 week was again rising above 3 mmol/l. Neck ultrasound failed to locate a parathyroid adenoma. Sestamibi scan suggested a large ectopic parathyroid adenoma within the superior mediastinum which was confirmed on CT imaging. She subsequently underwent urgent surgical removal of a 5.5×2.5 cm parathyroid adenoma via neck dissection with no post-surgical complications and normalisation of serum calcium (2.36 mmol/l) and PTH (3.1 pmol/l) 1 week post-op.

Conclusion: Primary hyperparathyroidism can present with reduced conscious state and profound confusion, requiring urgent treatment. Cinacalcet is a useful agent to manage severe hypercalcaemia, however the effects of cinacalcet as demonstrated in this case may be transient. Accurate pre-operative localisation is particularly important in cases of severe hypercalcaemia as the consequence of failed surgery can be disastrous due to the risk of developing hypercalcaemic crisis.