Endocrine Abstracts

We report the case of a 77-year-old lady who presented to hospital with confusion, agitation and polyuria. She had type 2 diabetes mellitus but was otherwise well with no history of weight loss, nephrolithiasis or fractures. There was no relevant family history. There were no abnormal findings on examination apart from dehydration and no focal neurological signs or lymphadenopathy. Investigations revealed a serum corrected calcium level of 4.71 nmol/l (normal 2.1–2.6). Her parathyroid hormone level was also markedly elevated at 113 pmol/l (normal 1.5–7.6). Vitamin D level was 29 nmol/l. A previous calcium level 3 years ago had been normal. Myeloma screen was negative. She was treated with i.v. fluid rehydration and 90 mg i.v. pamidronate. Her serum calcium levels corrected over the next 10 days with improvement in her symptoms.

Ultrasound scan of the neck revealed an incidental 2×1.5 cm mass in the lower pole of the right thyroid gland. Nuclear medicine parathyroid (sestamibi) scan was consistent with a left sided parathyroid adenoma. On the basis of these investigations a left upper parathyroidectomy was performed. Histology revealed 0.96 g nodular parathyroid tissue consistent with an adenoma. The patient was well and asymptomatic three months after the procedure with normal calcium levels.

Corrected calcium levels of >3 are unusual in primary hyperparathyroidism and levels >4 are rare. The extremely high calcium and parathyroid hormone levels accounted for this lady’s florid symptoms and were initially suggestive of parathyroid carcinoma. Findings following parathyroidectomy confirmed an adenoma.